DSP56321 Reference Manual

DSP56321 Reference Manual
24-Bit Digital Signal Processor
DSP56321RM
Rev. 1, March 2005
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Document Order Number: DSP56321RM
Rev. 1
3/2005
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© Freescale Semiconductor, Inc. 2001, 2005.
Overview
1
Signals/Connections
2
Memory Configuration
3
Core Configuration
4
Clock Configuration
5
Programming the Peripherals
6
Host Interface (HI08)
7
Enhanced Synchronous Serial Interface (ESSI)
8
Serial Communications Interface (SCI)
9
Triple Timer Module
10
Enhanced Filter Coprocessor (EFCOP)
11
Bootstrap Program
A
Programming Reference
B
Index
IND
1
Overview
2
Signals/Connections
3
Memory Configuration
4
Core Configuration
5
Clock Configuration
6
Programming the Peripherals
7
Host Interface (HI08)
8
Enhanced Synchronous Serial Interface (ESSI)
9
Serial Communications Interface (SCI)
10
Triple Timer Module
11
Enhanced Filter Coprocessor (EFCOP)
A
Bootstrap Program
B
Programming Reference
IND
Index
Contents
1
Overview
1.1
1.2
1.3
1.4
1.4.1
1.4.1.1
1.4.1.2
1.4.2
1.4.3
1.4.4
1.4.5
1.4.6
1.4.7
1.5
1.6
1.7
1.8
1.8.1
1.8.2
1.8.3
1.8.4
1.8.5
1.8.6
Manual Organization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Manual Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
DSP56300 Core Functional Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Data ALU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Data ALU Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Multiplier-Accumulator (MAC). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Address Generation Unit (AGU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Program Control Unit (PCU). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Clock Generator Circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
JTAG TAP and OnCE Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
On-Chip Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Off-Chip Memory Expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
Internal Buses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
DMA Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Peripherals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
GPIO Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
HI08 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
ESSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
SCI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Timer Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
EFCOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
2
Signals/Connections
2.1
2.2
2.3
2.4
2.5
2.5.1
2.5.2
2.5.3
2.6
2.7
2.8
2.9
2.10
2.11
2.12
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
PLL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
External Memory Expansion Port (Port A). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
External Address Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
External Data Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
External Bus Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Interrupt and Mode Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
HI08 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Enhanced Synchronous Serial Interface 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Enhanced Synchronous Serial Interface 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
SCI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Timers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
JTAG and OnCE Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
v
Contents
3
Memory Configuration
3.1
3.1.1
3.1.2
3.1.3
3.2
3.2.1
3.2.2
3.2.3
3.3
3.3.1
3.3.2
3.3.3
3.3.4
3.4
3.5
3.6
3.7
Program Memory Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Internal Program Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Memory Switch Modes—Program Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Program Bootstrap ROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
X Data Memory Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Internal X Data Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Memory Switch Modes—X Data Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Internal X I/O Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Y Data Memory Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Internal Y Data Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Memory Switch Modes—Y Data Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Internal Y I/O Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
External Y I/O Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Summary of Memory Switch Mode Configurations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Dynamic Memory Configuration Switching. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Sixteen-Bit Compatibility Mode Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Memory Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
4
Core Configuration
4.1
4.2
4.3
4.3.1
4.3.2
4.4
4.4.1
4.4.2
4.4.3
4.5
4.5.1
4.5.2
4.6
4.7
4.8
4.9
Operating Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Bootstrap Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Central Processor Unit (CPU) Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Status Register (SR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Operating Mode Register (OMR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
Configuring Interrupts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13
Interrupt Priority Registers (IPRC and IPRP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13
Interrupt Table Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14
Processing Interrupt Source Priorities Within an IPL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-16
Bus Interface Unit (BIU) Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
Bus Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
Address Attribute Registers (AAR[0–3]) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-20
DMA Control Registers 5–0 (DCR[5–0]). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-22
Device Identification Register (IDR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-27
JTAG Identification (ID) Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-28
JTAG Boundary Scan Register (BSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-28
5
Clock Configuration
5.1
5.2
5.3
5.4
5.5
5.5.1
5.6
5.6.1
5.6.2
5.6.3
5.7
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Clock Generation Scheme. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Clock Acronym List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
CLKGEN External Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
DPLL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
DPLL Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Clock Generator Output Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
EXTAL as Clock Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
DPLL as Clock Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Global Clock Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
CLKGEN Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
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Freescale Semiconductor
Contents
5.7.1
5.7.2
DPLL Clock Control (PCTL) Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
DPLL Static Control Register (DSCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
6
Programming the Peripherals
6.1
6.2
6.3
6.4
6.4.1
6.4.2
6.4.3
6.4.4
6.5
6.5.1
6.5.2
6.5.3
6.5.4
6.5.5
Peripheral Initialization Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Mapping the Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Reading Status Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Data Transfer Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
DMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Advantages and Disadvantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
General-Purpose Input/Output (GPIO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Port B Signals and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Port C Signals and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Port D Signals and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Port E Signals and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Triple Timer Signals and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
7
Host Interface (HI08)
7.1
7.1.1
7.1.2
7.2
7.3
7.4
7.4.1
7.4.2
7.4.3
7.4.4
7.4.5
7.5
7.6
7.6.1
7.6.2
7.6.3
7.6.4
7.6.5
7.6.6
7.6.7
7.6.8
7.6.9
7.7
7.7.1
7.7.2
7.7.3
7.7.4
7.7.5
7.7.6
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
DSP Core Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Host Processor Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Host Port Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Software Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Core Interrupts and Host Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Core DMA Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Host Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Endian Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Boot-up Using the HI08 Host Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
DSP Core Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
Host Control Register (HCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
Host Status Register (HSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
Host Data Direction Register (HDDR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-14
Host Data Register (HDR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15
Host Base Address Register (HBAR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15
Host Port Control Register (HPCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16
Host Transmit (HTX) Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-19
Host Receive (HRX) Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-19
DSP-Side Registers After Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-20
Host Programmer Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-20
Interface Control Register (ICR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-22
Command Vector Register (CVR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-24
Interface Status Register (ISR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-25
Interrupt Vector Register (IVR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-27
Receive Data Registers (RXH:RXM:RXL). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-27
Transmit Data Registers (TXH:TXM:TXL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-28
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Contents
7.7.7
7.8
Host-Side Registers After Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-28
Programming Model Quick Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-29
8
Enhanced Synchronous Serial Interface
8.1
8.1.1
8.1.2
8.1.3
8.1.4
8.1.5
8.1.6
8.2
8.2.1
8.2.2
8.2.3
8.3
8.3.1
8.3.2
8.3.3
8.3.4
8.3.5
8.3.6
8.3.7
8.3.8
8.3.9
8.4
8.4.1
8.4.2
8.4.3
8.4.4
8.4.5
8.4.6
8.4.7
8.4.8
8.4.9
8.4.10
8.5
8.5.1
8.5.2
8.5.3
ESSI Data and Control Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Serial Transmit Data Signal (STD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Serial Receive Data Signal (SRD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Serial Clock (SCK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Serial Control Signal (SC0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Serial Control Signal (SC1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Serial Control Signal (SC2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
ESSI After Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
Operating Modes: Normal, Network, and On-Demand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
Normal/Network/On-Demand Mode Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
Synchronous/Asynchronous Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Frame Sync Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Frame Sync Signal Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Frame Sync Length for Multiple Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Word Length Frame Sync and Data Word Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
Frame Sync Polarity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
Byte Format (LSB/MSB) for the Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
Flags. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-12
ESSI Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-12
ESSI Control Register A (CRA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-13
ESSI Control Register B (CRB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-17
ESSI Status Register (SSISR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-26
ESSI Receive Shift Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-27
ESSI Receive Data Register (RX) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-28
ESSI Transmit Shift Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-28
ESSI Transmit Data Registers (TX[2–0]) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-31
ESSI Time Slot Register (TSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-31
Transmit Slot Mask Registers (TSMA, TSMB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-31
Receive Slot Mask Registers (RSMA, RSMB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-32
GPIO Signals and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-33
Port Control Registers (PCRC and PCRD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-33
Port Direction Registers (PRRC and PRRD). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-34
Port Data Registers (PDRC and PDRD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-35
9
9.1
9.1.1
9.1.2
9.1.3
9.1.3.1
9.1.3.2
9.1.3.3
Serial Communication Interface
Operating Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Synchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Asynchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Multi-Drop Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Transmitting Data and Address Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Wired-OR Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Idle Line Wakeup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
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9.1.3.4
9.2
9.2.1
9.2.2
9.2.3
9.3
9.4
9.4.1
9.4.2
9.5
9.6
9.6.1
9.6.2
9.6.3
9.6.4
9.6.4.1
9.6.4.2
9.7
9.7.1
9.7.2
9.7.3
Address Mode Wakeup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
I/O Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Receive Data (RXD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
Transmit Data (TXD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
SCI Serial Clock (SCLK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
SCI After Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
SCI Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-6
Preamble, Break, and Data Transmission Priority. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
Bootstrap Loading Through the SCI (Boot Mode 2 or A). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
Exceptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
SCI Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
SCI Control Register (SCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-11
SCI Status Register (SSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-14
SCI Clock Control Register (SCCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-16
SCI Data Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19
SCI Receive Register (SRX) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-20
SCI Transmit Register (STX). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-21
GPIO Signals and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-22
Port E Control Register (PCRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-22
Port E Direction Register (PRRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-22
Port E Data Register (PDRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-23
10
Triple Timer Module
10.1
10.1.1
10.1.2
10.2
10.2.1
10.2.2
10.2.3
10.3
10.3.1
10.3.1.1
10.3.1.2
10.3.1.3
10.3.1.4
10.3.2
10.3.2.1
10.3.2.2
10.3.2.3
10.3.3
10.3.4
10.3.4.1
10.3.4.2
10.3.4.3
10.3.5
10.3.6
10.4
10.4.1
10.4.2
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1
Triple Timer Module Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1
Individual Timer Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-2
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
Timer After Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
Timer Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
Timer Exceptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
Operating Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Triple Timer Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Timer GPIO (Mode 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Timer Pulse (Mode 1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timer Toggle (Mode 2)10-8
Timer Event Counter (Mode 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-10
Signal Measurement Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-11
Measurement Input Width (Mode 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-11
Measurement Input Period (Mode 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-13
Measurement Capture (Mode 6). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-15
Pulse Width Modulation (PWM, Mode 7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-16
Watchdog Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-18
Watchdog Pulse (Mode 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-19
Watchdog Toggle (Mode 10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-20
Reserved Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-20
Special Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-21
DMA Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-21
Triple Timer Module Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-21
Prescaler Counter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-21
Timer Prescaler Load Register (TPLR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-23
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Contents
10.4.3
10.4.4
10.4.5
10.4.6
10.4.7
Timer Prescaler Count Register (TPCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-24
Timer Control/Status Register (TCSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-24
Timer Load Register (TLR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-29
Timer Compare Register (TCPR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-30
Timer Count Register (TCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-30
11
Enhanced Filter Coprocessor
11.1
11.2
11.2.1
11.2.2
11.2.3
11.3
11.3.1
11.3.2
11.3.2.1
11.3.2.2
11.3.3
11.3.3.1
11.3.3.1.1
11.3.3.1.2
11.3.3.1.3
11.3.3.1.4
11.3.3.2
11.3.3.2.1
11.3.3.2.2
11.3.3.2.3
11.3.3.2.4
11.3.4
11.3.5
11.3.6
11.3.6.1
11.3.6.1.1
11.3.6.1.2
11.3.6.1.3
11.3.6.2
11.3.6.3
11.3.6.3.1
11.3.6.3.2
11.3.6.3.3
11.3.6.4
11.3.6.4.1
11.3.6.4.2
11.3.6.4.3
11.3.6.4.4
11.3.6.4.5
11.4
11.4.1
11.4.2
11.4.3
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1
Architecture Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
PMB Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
EFCOP Memory Banks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
Filter Multiplier and Accumulator (FMAC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-5
EFCOP Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-6
EFCOP Operation Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-7
EFCOP Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-7
FIR Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-7
IIR Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-7
FIR Filter Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-8
FIR Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-8
Real Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-8
Complex Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-9
Alternating Complex Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-9
Magnitude Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-10
FIR Filter Type Processing Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-10
Coefficient Update Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-10
Adaptive Mode Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-10
Multichannel Mode Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-11
Decimation Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-11
IIR Filter Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-11
EFCOP Data Transfer Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-12
EFCOP Operation Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-14
Real FIR Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-14
DMA Input/DMA Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-14
DMA Input/Polling Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-18
DMA Input/Interrupt Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-20
Real FIR Filter With Decimation by M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-23
Adaptive FIR Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-24
Implementation Using Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-26
Implementation Using DMA Input and Interrupt Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-27
Updating an FIR Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-27
Verification for Filter Examples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-32
Input Sequence (input.asm). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-32
Filter Coefficients (coefs.asm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-33
Output Sequence for Examples 11-1, 11-2, and 11-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-33
Desired Signal for Example 11-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-34
Output Sequence for Example 11-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-34
EFCOP Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-35
Filter Data Input Register (FDIR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-35
Filter Data Output Register (FDOR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-35
Filter K-Constant Input Register (FKIR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-36
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Contents
11.4.4
11.4.5
11.4.6
11.4.7
11.4.8
11.4.9
11.4.10
Filter Count (FCNT) Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-36
EFCOP Control Status Register (FCSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-37
EFCOP ALU Control Register (FACR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-39
EFCOP Data Base Address (FDBA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-41
EFCOP Coefficient Base Address (FCBA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-41
Decimation/Channel Count Register (FDCH). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-41
EFCOP Interrupt Vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-42
A
Bootstrap Program
B
Programming Reference
B.1
B.2
B.3
Internal I/O Memory Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-2
Interrupt Sources and Priorities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-7
Programming Sheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-11
Index
DSP56321 Reference Manual, Rev. 1
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Contents
DSP56321 Reference Manual, Rev. 1
xii
Freescale Semiconductor
1
Overview
The Freescale DSP56321, a member of the DSP56300 DSP family, supports networking, security
encryption, and home entertainment using a high-performance, single-clock-cycle-perinstruction engine (DSP56000 code-compatible), a barrel shifter, 24-bit addressing, an
instruction cache, and a direct memory access (DMA) controller. The DSP56321 offers 275
million multiply- accumulates per second (MMACS) performance, attaining 550 MMACS when
the EFCOP is in use. It operates with an internal 275 MHz clock with a 1.6 volt core and
independent 3.3 volt input/output (I/O) power. By operating in parallel with the core, the EFCOP
provides overall enhanced performance and signal quality with no impact on channel throughput
or total channel support. This device is pin-compatible with the Freescale DSP56303,
DSP56L307, DSP56309, and DSP56311. All DSP56300 core family members contain the
DSP56300 core and additional modules. The modules are chosen from a library of standard
predesigned elements, such as memories and peripherals. A standard interface between the
DSP56300 core and the on-chip memory and peripherals supports a wide variety of memory and
peripheral configurations. In particular, the DSP56321 includes the Freescale JTAG port and
OnCE module.
The DSP56321 is intended for applications requiring a large amount of internal memory, such as
networking and wireless infrastructure applications. The on-board EFCOP can accelerate general
filtering applications, such as echo-cancellation applications, correlation, and general-purpose
convolution-based algorithms.
This manual describes the DSP56321 24-bit DSP, its memory, operating modes, and peripheral
modules. The DSP56321 is an implementation of the DSP56300 core with a unique configuration
of on-chip memory, cache, and peripherals. Use this manual in conjunction with the DSP56300
Family Manual (DSP56300FM/AD), which describes the CPU, core programming models, and
instruction set.
Note:
The DSP56321 digital phase-lock loop (DPLL) and clock modules differ from other
members of the DSP56300 family. For details on these modules, including the
programming model, see Chapter 4 of this manual.
The DSP56321 Technical Data (DSP56321)—referred to as the data sheet—provides DSP56321
electrical specifications, timing, pinout, and packaging descriptions.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
1-1
Overview
You can obtain these documents and the DSP development tools through a local Freescale
semiconductor sales office or authorized distributor. To receive the latest information on this
DSP, access the web site listed on the back cover of this document.
1.1 Manual Organization
This manual contains the following sections and appendices:
„
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„
„
„
„
„
„
„
„
„
„
Chapter 1, Overview. Features list and block diagram, related documentation,
organization of this manual, and the notational conventions used.
Chapter 2, Signals/Connections. DSP56321 signals and their functional groupings.
Chapter 3, Memory Configuration. DSP56321 memory spaces, RAM configuration,
memory configuration bit settings, memory configurations, and memory maps.
Chapter 4, Core Configuration. Registers for configuring the DSP56300 core when
programming the DSP56321, in particular the interrupt vector locations and the operation
of the interrupt priority registers; operating modes and how they affect the processor’s
program and data memories. This chapter also provides detailed information about the
Digital Phase-Lock Loop (DPLL) and clock modules that are unique to the DSP56321.
Chapter 5, Programming the Peripherals. Guidelines on initializing the DSP56321
peripherals, including mapping control registers, specifying a method of transferring data,
and configuring for general-purpose input/output (GPIO).
Chapter 6, Host Interface (HI08). Features, signals, architecture, programming model,
reset, interrupts, external host programming model, initialization, and a quick reference to
the HI08 programming model.
Chapter 7, Enhanced Synchronous Serial Interface (ESSI). Enhancements, data and
control signals, programming model, operating modes, initialization, exceptions, and
GPIO.
Chapter 8, Serial Communication Interface (SCI). Signals, programming model,
operating modes, reset, initialization, and GPIO.
Chapter 9, Triple Timer Module. Architecture, programming model, and operating modes
of three identical timer devices available for use as internals or event counters.
Chapter 10, Enhanced Filter Coprocessor (EFCOP). Structure and function of the
EFCOP, including features, architecture, and programming model; programming topics
such as data transfer to and from the EFCOP, its use in different modes, and examples of
usage.
Appendix A, Bootstrap Code. Bootstrap code for the DSP56321.
Appendix B, Programming Reference. Peripheral addresses, interrupt addresses, and
interrupt priorities for the DSP56321; programming sheets listing the contents of the
major DSP56321 registers for programmer’s reference.
DSP56321 Reference Manual, Rev. 1
1-2
Freescale Semiconductor
Manual Conventions
1.2 Manual Conventions
This manual uses the following conventions:
„
„
„
„
Register bits are listed from most significant bit (MSB) to least significant bit (LSB).
Bits within a register are indicated AA[n–m], n > m, when more than one bit is described.
The bits are presented as if they are contiguous within a register. However, this is not
always the case. Refer to the programming model diagrams or to the programmer’s sheets
to see the exact bit locations within a register.
A “set,” bit has a value of 1. A “cleared” bit has a value of 0.
The word “assert” means that a high true (active high) signal is pulled high to VCC or that
a low true (active low) signal is pulled low to ground. The word “deassert” means that a
high true signal is pulled low to ground or that a low true signal is pulled high to VCC. See
Table 1-1.
Table 1-1. High True/Low True Signal Conventions
Signal/Symbol
Logic State
Signal State
Voltage
PIN1
True
Asserted
Ground2
PIN
False
Deasserted
VCC3
PIN
True
Asserted
VCC
PIN
False
Deasserted
Ground
Notes: 1.
2.
3.
„
„
„
„
PIN is a generic term for any pin on the chip.
Ground is an acceptable low voltage level. See the appropriate data sheet for the range of
acceptable low voltage levels (typically a TTL logic low).
VCC is an acceptable high voltage level. See the appropriate data sheet for the range of
acceptable high voltage levels (typically a TTL logic high).
Pins or signals that are asserted low (made active when pulled to ground) are indicated as
follows:
— In text, they have an overbar: for example, RESET is asserted low.
— In code examples, they have a tilde in front of their names. In Example 1-1, line 3
refers to the SS0 signal (shown as ~SS0).
Sets of signals are indicated by the first and last signals in the set, for instance HA[0–3].
“Input/Output” indicates a bidirectional signal. “Input or Output” indicates a signal that is
exclusively one or the other.
Code examples are displayed in a monospaced font, as shown in Example 1-1.
Example 1-1. Sample Code Listing
BFSET#$0007,X:PCC; Configure:
;
MISO0, MOSI0, SCK0 for SPI master
; ~SS0 as PC3 for GPIO
line 1
line 2
line 3
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
1-3
Overview
„
„
Hexadecimal values are indicated with a $ preceding the hex value, as follows: $FFFFFF
is the X memory address for the core interrupt priority register.
The word “reset” is used in four different contexts in this manual:
— the reset signal, written as RESET
— the reset instruction, written as RESET
— the reset operating state, written as Reset
— the reset function, written as reset
1.3 Manual Revision History for Revision 1
Table 1-2 lists the changes made in this manual from Revision 0 to Revision 1.
Table 1-2. Change History, Revision 3 to Revision 4
Section Number
Revision 3
Page Number
Revision 4
Page Number
Figure 2-1
Table 2-8
Table 2-10
Table 2-11
Table 2-12
Table 2-13
Table 2-14
Page 2-2
Page 2-5
Page 2-8
Page 2-11
Page 2-13
Page 2-15
Page 2-16
Page 2-2
Page 2-5
Page 2-8
Page 2-11
Page 2-12
Page 2-14
Page 2-15
New Operating Mode Register (OMR) layout and bit
definitions.
Section 4.3.2
Page 4-10
Page 4-9
New Bus Control Register (BCR) layout and bit
definitions.
Section 4.5.1
Page 4-20
Page 4-18
Updated GPIO signal names.
Section 6.5.1, Figure 6-2
Section 6.5.4, Figure 6-5
Page 6-7
Page 6-8
Page 6-6
Page 6-7
Updated HDR address
Section 7.6.3, Figure 7-9
Page 7-16
Page 7-14
Updated SCI Receive Register (SRX) description
Section 9.6.4.1
Page 9-24
Page 9-21
Updated programming sheets for the OMR, BCR,
Address Attribute Registers (AAR[3–0]), and timer
registers (TLR, TCPR, TCR).
Figure B-2
Figure B-7
Figure B-8
Figure B-22
Page B-14
Page B-19
Page B-20
Page B-34
Page B-12
Page B-15
Page B-16
Page B-30
Change
Modified signal definitions for some external bus
control, HI08, ESSI, SCI, and timer signals.
1.4 Features
Table 2 lists the features of the DSP56321 device.
DSP56321 Reference Manual, Rev. 1
1-4
Freescale Semiconductor
Features
Table 1-3. DSP56321 Features
Feature
Description
High-Performance
DSP56300 Core
• 275 million multiply-accumulates per second (MMACS) (550 MMACS using the EFCOP in
filtering applications) with a 275 MHz clock at 1.6 V core and 3.3 V I/O
• Object code compatible with the DSP56000 core with highly parallel instruction set
• Data arithmetic logic unit (Data ALU) with fully pipelined 24 × 24-bit parallel
Multiplier-Accumulator (MAC), 56-bit parallel barrel shifter (fast shift and normalization; bit
stream generation and parsing), conditional ALU instructions, and 24-bit or 16-bit arithmetic
support under software control
• Program control unit (PCU) with position independent code (PIC) support, addressing modes
optimized for DSP applications (including immediate offsets), internal instruction cache
controller, internal memory-expandable hardware stack, nested hardware DO loops, and fast
auto-return interrupts
• Direct memory access (DMA) with six DMA channels supporting internal and external
accesses; one-, two-, and three-dimensional transfers (including circular buffering);
end-of-block-transfer interrupts; and triggering from interrupt lines and all peripherals
• Phase-lock loop (PLL) allows change of low-power divide factor (DF) without loss of lock and
output clock with skew elimination
• Hardware debugging support including on-chip emulation (OnCE) module, Joint Test Action
Group (JTAG) test access port (TAP)
Enhanced Filter
Coprocessor (EFCOP)
• Internal 24 × 24-bit filtering and echo-cancellation coprocessor that runs in parallel to the DSP
core
• Operation at the same frequency as the core (up to 275 MHz)
• Support for a variety of filter modes, some of which are optimized for cellular base station
applications:
− Real finite impulse response (FIR) with real taps
− Complex FIR with complex taps
− Complex FIR generating pure real or pure imaginary outputs alternately
− A 4-bit decimation factor in FIR filters, thus providing a decimation ratio up to 16
− Direct form 1 (DFI) Infinite Impulse Response (IIR) filter
− Direct form 2 (DFII) IIR filter
− Four scaling factors (1, 4, 8, 16) for IIR output
− Adaptive FIR filter with true least mean square (LMS) coefficient updates
− Adaptive FIR filter with delayed LMS coefficient updates
Internal Peripherals
• Enhanced 8-bit parallel host interface (HI08) supports a variety of buses (for example, ISA) and
provides glueless connection to a number of industry-standard microcomputers,
microprocessors, and DSPs
• Two enhanced synchronous serial interfaces (ESSI), each with one receiver and three
transmitters (allows six-channel home theater)
• Serial communications interface (SCI) with baud rate generator
• Triple timer module
• Up to 34 programmable general-purpose input/output (GPIO) pins, depending on which
peripherals are enabled
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
1-5
Overview
Table 1-3. DSP56321 Features (Continued)
Feature
Description
:
• 192 × 24-bit bootstrap ROM
• 192 K × 24-bit RAM total
• Program RAM, instruction cache, X data RAM, and Y data RAM sizes are programmable:
Program RAM
Size
Internal Memories
Instruction
Cache Size
X Data RAM
Size*
Y Data RAM
Size*
Instruction
Cache
MSW2
MSW1
32 K × 24-bit
0
31 K × 24-bit
1024 × 24-bit
40 K × 24-bit
0
39 K × 24-bit
1024 × 24-bit
48 K × 24-bit
0
47 K × 24-bit
1024 × 24-bit
64 K × 24-bit
0
63 K × 24-bit
1024 × 24-bit
72 K × 24-bit
0
71 K × 24-bit
1024 × 24-bit
80 K × 24-bit
79 K × 24-bit
96 K × 24-bit
95 K × 24-bit
MSW0
80 K × 24-bit
80 K × 24-bit
disabled
0
0
0
80 K × 24-bit
80 K × 24-bit
enabled
0
0
0
76 K × 24-bit
76 K × 24-bit
disabled
0
0
1
76 K × 24-bit
76 K × 24-bit
enabled
0
0
1
72 K × 24-bit
72 K × 24-bit
disabled
0
1
0
72 K × 24-bit
72 K × 24-bit
enabled
0
1
0
64 K × 24-bit
64 K × 24-bit
disabled
0
1
1
64 K × 24-bit
64 K × 24-bit
enabled
0
1
1
60 K × 24-bit
60 K × 24-bit
disabled
1
0
0
60 K × 24-bit
60 K × 24-bit
enabled
1
0
0
0
56 K × 24-bit
56 K × 24-bit
disabled
1
0
1
1024 × 24-bit
56 K × 24-bit
56 K × 24-bit
enabled
1
0
1
0
48 K × 24-bit
48 K × 24-bit
disabled
1
1
0
1024 × 24-bit
48 K × 24-bit
48 K × 24-bit
enabled
1
1
0
112 K × 24-bit
0
40 K × 24-bit
40 K × 24-bit
disabled
1
1
1
111 K × 24-bit
1024 × 24-bit
40 K × 24-bit
40 K × 24-bit
enabled
1
1
1
*Includes 12 K × 24-bit shared memory (that is, 24 K total memory shared by the core and the EFCOP)
External Memory
Expansion
Power Dissipation
Packaging
• Data memory expansion to two 256 K × 24-bit word memory spaces using the standard
external address lines
• Program memory expansion to one 256 K × 24-bit words memory space using the standard
external address lines
• External memory expansion port
• Chip select logic for glueless interface to static random access memory (SRAMs)
•
•
•
•
Very low-power CMOS design
Wait and Stop low-power standby modes
Fully static design specified to operate down to 0 Hz (dc)
Optimized power management circuitry (instruction-dependent, peripheral-dependent, and
mode-dependent)
• Molded array plastic-ball grid array (MAP-BGA) package in lead-free or lead-bearing versions.
1.5 DSP56300 Core Functional Blocks
The functional blocks of the DSP56300 core are:
„
„
„
„
„
„
Data arithmetic logic unit (ALU)
Address generation unit (AGU)
Program control unit
DPLL and clock oscillator
JTAG TAP and OnCE module
Memory
In addition, the DSP56321 provides a set of on-chip peripherals, discussed in
Section 1.9, Peripherals, on page 1-13.
DSP56321 Reference Manual, Rev. 1
1-6
Freescale Semiconductor
DSP56300 Core Functional Blocks
1.5.1 Data ALU
The data ALU performs all the arithmetic and logical operations on data operands in the
DSP56300 core. These are the components of the data ALU:
„
„
„
„
„
„
„
Fully pipelined 24 × 24-bit parallel multiplier-accumulator
Bit field unit, comprising a 56-bit parallel barrel shifter (fast shift and normalization; bit
stream generation and parsing)
Conditional ALU instructions
Software-controllable 24-bit, 48-bit, or 56-bit arithmetic support
Four 24-bit or 48-bit input general-purpose registers: X1, X0, Y1, and Y0
Six data ALU registers (A2, A1, A0, B2, B1, and B0) that are concatenated into two
general-purpose, 56-bit accumulators, A and B, accumulator shifters
Two data bus shifter/limiter circuits
1.5.1.1 Data ALU Registers
The data ALU registers are read or written over the X data bus and the Y data bus as 16- or 32-bit
operands. The source operands for the data ALU can be 16, 32, or 40 bits and always originate
from data ALU registers. The results of all data ALU operations are stored in an accumulator.
Data ALU operations are performed in two clock cycles in a pipeline so that a new instruction
can be initiated in every clock cycle, yielding an effective execution rate of one instruction per
clock cycle. The destination of every arithmetic operation can be a source operand for the
immediately following operation without penalty.
1.5.1.2 Multiplier-Accumulator (MAC)
The MAC unit comprises the main arithmetic processing unit of the DSP56300 core and
performs all of the calculations on data operands. For arithmetic instructions, the unit accepts as
many as three input operands and outputs one 56-bit result of the following form: extension:most
significant product:least significant product (EXT:MSP:LSP).
The multiplier executes 24-bit × 24-bit parallel, fractional multiplies between twos-complement
signed, unsigned, or mixed operands. The 48-bit product is right-justified and added to the 56-bit
contents of either the A or B accumulator. A 56-bit result can be stored as a 24-bit operand. The
LSP is either truncated or rounded into the MSP. Rounding is performed if specified.
1.5.2 Address Generation Unit (AGU)
The AGU performs the effective address calculations using integer arithmetic necessary to
address data operands in memory and contains the registers that generate the addresses. It
implements four types of arithmetic: linear, modulo, multiple wrap-around modulo, and
reverse-carry. The AGU operates in parallel with other chip resources to minimize
address-generation overhead.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
1-7
Overview
The AGU is divided into halves, each with its own identical address ALU. Each address ALU has
four sets of register triplets, and each register triplet includes an address register, offset register,
and modifier register. Each contains a 24-bit full adder (called an offset adder). A second full
adder (called a modulo adder) adds the summed result of the first full adder to a modulo value
that is stored in its respective modifier register. A third full adder (called a reverse-carry adder) is
also provided. The offset adder and the reverse-carry adder work in parallel and share common
inputs. The only difference between them is that the carry propagates in opposite directions. Test
logic determines which of the three summed results of the full adders is output.
Each address ALU can update one address register from its own address register file during one
instruction cycle. The contents of the associated modifier register specify the type of arithmetic
used in the address register update calculation. The modifier value is decoded in the address
ALU.
1.5.3 Program Control Unit (PCU)
The PCU fetches and decodes instructions, controls hardware DO loops, and processes
exceptions. Its seven-stage pipeline controls the different processing states of the DSP56300
core. The PCU consists of three hardware blocks:
„
„
„
Program decode controller — decodes the 24-bit instruction loaded into the instruction
latch and generates all signals for pipeline control.
Program address generator — contains all the hardware needed for program address
generation, system stack, and loop control.
Program interrupt controller — arbitrates among all interrupt requests (internal interrupts,
as well as the five external requests IRQA, IRQB, IRQC, IRQD, and NMI), and generates the
appropriate interrupt vector address.
PCU features include the following:
„
„
„
„
„
„
„
Position-independent code support
Addressing modes optimized for DSP applications (including immediate offsets)
On-chip instruction cache controller
On-chip memory-expandable hardware stack
Nested hardware DO loops
Fast auto-return interrupts
Hardware system stack
The PCU uses the following registers:
„
„
„
Program counter register
Status register
Loop address register
DSP56321 Reference Manual, Rev. 1
1-8
Freescale Semiconductor
DSP56300 Core Functional Blocks
„
„
„
„
„
„
Loop counter register
Vector base address register
Size register
Stack pointer
Operating mode register
Stack counter register
1.5.4 Clock Generator Circuit
The DSP56321 contain a Clock Generator (CLKGEN) that is different from the clock generator
and Phase-Lock Loop (PLL) used by other members of the DSP56300 family. The DSP56321
uses a CLKGEN module with an integrated Digital Phase-Lock Loop (DPLL). As with the
previous clock generator, the DSP56321 allows you to change the low-power Division Factor
(DF) without losing lock.
The CLKGEN module uses two internal X-I/O-mapped registers that are different from the
standard DSP56300 design described in the DSP56300 Family Manual. Chapter 5 describes the
new clock registers in detail.
The DPLL allows the processor to operate at a high internal clock frequency using a
low-frequency clock input, a feature that offers two immediate benefits:
„
„
A lower-frequency clock input reduces the overall electromagnetic interference generated
by a system.
The ability to oscillate at different frequencies reduces costs by eliminating the need to
add additional oscillators to a system.
1.5.5 JTAG TAP and OnCE Module
In the DSP56300 core is a dedicated user-accessible TAP that is fully compatible with the IEEE
1149.1 Standard Test Access Port and Boundary Scan Architecture. Problems with testing
high-density circuit boards led to the development of this standard under the sponsorship of the
Test Technology Committee of IEEE and the JTAG. The DSP56300 core implementation
supports circuit-board test strategies based on this standard. The test logic includes a TAP with
four dedicated signals, a 16-state controller, and three test data registers. A boundary scan
register links all device signals into a single shift register. The test logic, implemented utilizing
static logic design, is independent of the device system logic. For details on the JTAG port,
consult the DSP56300 Family Manual.
The OnCE module interacts with the DSP56300 core and its peripherals nonintrusively so that
you can examine registers, memory, or on-chip peripherals. This facilitates hardware and
software development on the DSP56300 core processor. OnCE module functions are provided
through the JTAG TAP signals. For details on the OnCE module, consult the DSP56300 Family
Manual.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
1-9
Overview
1.5.6 On-Chip Memory
The memory space of the DSP56300 core is partitioned into program, X data, and Y data
memory space. The data memory space is divided into X and Y data memory in order to work
with the two address ALUs and to feed two operands simultaneously to the data ALU. Memory
space includes internal RAM and ROM and can be expanded off-chip under software control.
There is an on-chip 192 × 24-bit bootstrap ROM. For details on internal memory, see Chapter 3,
Memory Configuration. Program RAM, instruction cache, X data RAM, and Y data RAM size
are programmable, as Table 1-3, DSP56321 Features, on page 1-5 shows.
1.5.7 Off-Chip Memory Expansion
Memory can be expanded off chip to the following capacities:
„
„
Data memory expansion to two 256 K × 24-bit word memory spaces using standard
address lines
Program memory expansion to one 256 K × 24-bit word memory space using standard
address lines
Further features of off-chip memory include the following:
„
„
External memory expansion port
Simultaneous glueless interface to Static RAM (SRAM)
1.6 Internal Buses
To provide data exchange between blocks, the DSP56321 implements the following buses:
„
„
„
„
„
„
„
„
„
„
„
I/O expansion bus to peripherals
Program memory expansion bus to program ROM
X memory expansion bus to X memory
Y memory expansion bus to Y memory
Global data bus between PCU and other core structures
Program data bus for carrying program data throughout the core
X memory data bus for carrying X data throughout the core
Y memory data bus for carrying Y data throughout the core
Program address bus for carrying program memory addresses throughout the core
X memory address bus for carrying X memory addresses throughout the core
Y memory address bus for carrying Y memory addresses throughout the core
The block diagram in Figure 1-1 illustrates these buses among other components.
DSP56321 Reference Manual, Rev. 1
1-10
Freescale Semiconductor
Block Diagram
1.7 Block Diagram
All internal buses on the DSP56300 family members are 24-bit buses. The program data bus is
also a 24-bit bus. Figure 1-1 shows a block diagram of the DSP56321.
3
16
6
6
Memory Expansion Area
SCI
Interface
Triple
Timer
Host
ESSI
Interface Interface
(HI08)
Enhanced
Filter
Coprocessor
32 K × 24 bit or
X Data
(EFCOP)
31 K × 24 bit and
RAM
RAM
1024 × 24 bit
80 K × 24 bit
80 K × 24 bit
Program
RAM
Y Data
YAB
Address
Generation
Unit
YM_EB
PM_EB
PIO_EB
Peripheral
Expansion Area
XM_EB
Instruction
Cache
External
Address
Bus
Switch
XAB
PAB
DAB
Six Channel
DMA Unit
External
Bus
Interface
and
I - Cache
Control
24-Bit
Bootstrap
ROM
DSP56300
Core
18
Address
10
Control
DDB
Internal
Data
Bus
Switch
External
Data Bus
Switch
YDB
XDB
PDB
24
Data
GDB
Power
Management
CLOCK
Generator
DPLL
Program
Interrupt
Controller
Program
Decode
Controller
Program
Address
Generator
Data ALU
24 × 24+56 →56-bit MAC
Two 56-bit Accumulators
5
JTAG
OnCE™
Port
DE
56-bit Barrel Shifter
EXTAL
XTAL
MODA/IRQA
MODB/IRQB
MODC/IRQC
MODD/IRQD
RESET
PINIT/ NMI
Figure 1-1. DSP56321 Block Diagram
Note:
See Section 1.5.6, On-Chip Memory, on page 1-10 for details on memory size.
1.8 DMA Controller
The features of the DMA controller are as follows:
„
„
„
Six DMA channels supporting internal and external accesses
One-, two-, and three-dimensional transfers (including circular buffering)
End-of-block-transfer interrupts
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
1-11
Overview
„
Triggering from interrupt lines and all peripherals
1.9 Peripherals
In addition to the core features, the DSP56321 provides the following peripherals:
„
„
„
„
„
„
„
As many as 34 user-configurable GPIO signals
HI08 to external hosts
Dual ESSI
SCI
Triple timer module
Memory switch mode
Four external interrupt/mode control lines
1.9.1 GPIO Functionality
The GPIO port consists of up to 34 programmable signals, also used by the peripherals (HI08,
ESSI, SCI, and timer). There are no dedicated GPIO signals. After a reset, the signals are
automatically configured as GPIO. Three memory-mapped registers per peripheral control GPIO
functionality. Programming techniques for these registers to control GPIO functionality are
detailed in Chapter 6, Programming the Peripherals.
1.9.2 HI08
The HI08 is a byte-wide, full-duplex, double-buffered parallel port that can connect directly to
the data bus of a host processor. The HI08 supports a variety of buses and provides connection
with a number of industry-standard DSPs, microcomputers, and microprocessors without
requiring any additional logic. The DSP core treats the HI08 as a memory-mapped peripheral
occupying eight 24-bit words in data memory space. The DSP can use the HI08 as a
memory-mapped peripheral, using either standard polled or interrupt programming techniques.
Separate double-buffered transmit and receive data registers allow the DSP and host processor to
transfer data efficiently at high speed. Memory mapping allows you to program DSP core
communication with the HI08 registers using standard instructions and addressing modes.
1.9.3 ESSI
The DSP56321 provides two independent and identical ESSIs. Each ESSI has a full-duplex serial
port for communication with a variety of serial devices, including one or more industry-standard
codecs, other DSPs, microprocessors, and peripherals that implement the Freescale SPI. The
ESSI consists of independent transmitter and receiver sections and a common ESSI clock
generator. ESSI capabilities include the following:
DSP56321 Reference Manual, Rev. 1
1-12
Freescale Semiconductor
Peripherals
„
„
„
„
„
„
Independent (asynchronous) or shared (synchronous) transmit and receive sections with
separate or shared internal/external clocks and frame syncs
Normal mode operation using frame sync
Network mode operation with as many as 32 time slots
Programmable word length (8, 12, or 16 bits)
Program options for frame synchronization and clock generation
One receiver and three transmitters per ESSI
1.9.4 SCI
The SCI provides a full-duplex port for serial communication with other DSPs, microprocessors,
or peripherals such as modems. The SCI interfaces without additional logic to peripherals that
use TTL-level signals. With a small amount of additional logic, the SCI can connect to peripheral
interfaces that have non-TTL level signals, such as the RS-232C, RS-422, etc. This interface uses
three dedicated signals: transmit data, receive data, and SCI serial clock. It supports
industry-standard asynchronous bit rates and protocols, as well as high-speed synchronous data
transmission (up to 12.5 Mbps for a 100 MHz clock). SCI asynchronous protocols include a
multidrop mode for master/slave operation with wake-up on idle line and wake-up on address bit
capability. This mode allows the DSP56321 to share a single serial line efficiently with other
peripherals.
Separate SCI transmit and receive sections can operate asynchronously with respect to each
other. A programmable baud-rate generator provides the transmit and receive clocks. An enable
vector and an interrupt vector allow the baud-rate generator to function as a general-purpose
timer when the SCI is not using it or when the interrupt timing is the same as that of the SCI.
1.9.5 Timer Module
The triple timer module is composed of a common 21-bit prescaler and three independent and
identical general-purpose 24-bit timer/event counters, each with its own memory-mapped
register set. Each timer has the following properties:
„
„
„
A single signal that can function as a GPIO signal or as a timer signal
Uses internal or external clocking and can interrupt the DSP after a specified number of
events (clocks) or signal an external device after counting internal events
Connection to the external world through one bidirectional signal. When this signal is
configured as an input, the timer functions as an external event counter or measures
external pulse width/signal period. When the signal is used as an output, the timer
functions as either a timer, a watchdog, or a pulse width modulator.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
1-13
Overview
1.9.6 EFCOP
The EFCOP interfaces with the DSP core via the peripheral module bus. It is a general-purpose,
fully programmable coprocessor that performs filtering tasks concurrently with the DSP core,
with minimum core overhead. The DSP core and the EFCOP can share data via an 8K-word
shared data memory. DMA channels shuttle input and output data between the DSP core and the
EFCOP. The EFCOP supports a variety of filter modes, some of which are optimized for cellular
base station applications:
„
„
„
„
„
„
„
„
„
Real finite impulse response (FIR) with real taps
Complex FIR with complex taps
Complex FIR generating pure real or pure imaginary outputs alternately
A 4-bit decimation factor in FIR filters, thus providing a decimation ratio up to 16
Direct form 1 (DFI) infinite impulse response (IIR) filter
Direct form 2 (DFII) IIR filter
Four scaling factors (1, 4, 8, 16) for IIR output
Adaptive FIR filter with true least mean square (LMS) coefficient updates
Adaptive FIR filter with delayed LMS coefficient updates
The EFCOP supports up to 10K taps and 10K coefficients in any combination of number and
length of filters (for example, eight filters of length 512, or 16 filters of length 256). It performs
either 24-bit or 16-bit precision arithmetic with full support for saturation arithmetic. A
cost-effective and power-efficient coprocessor, the EFCOP accelerates filtering tasks, such as
echo cancellation or correlation, concurrently with software running on the DSP core.
DSP56321 Reference Manual, Rev. 1
1-14
Freescale Semiconductor
2
Signals/Connections
The DSP56321 input and output signals are organized into functional groups as shown in Table
2-1. Figure 2-1 diagrams the DSP56321 signals by functional group. The remainder of this
chapter describes the signal pins in each functional group
Table 2-1. DSP56321 Functional Signal Groupings
Functional Group
Number of Signals
Power (VCC)
20
Ground (GND)
66
Clock
2
PLL
1
Address bus
18
Port A1
Data bus
24
Bus control
10
Interrupt and mode control
5
Host interface (HI08)
Enhanced synchronous serial interface (ESSI)
Port B2
16
Ports C and D3
12
Port E4
3
Serial communication interface (SCI)
Timer
3
JTAG/OnCE Port
6
Notes: 1.
2.
3.
4.
5.
Port A signals define the external memory interface port, including the external address bus, data bus, and
control signals.
Port B signals are the HI08 port signals multiplexed with the GPIO signals.
Port C and D signals are the two ESSI port signals multiplexed with the GPIO signals.
Port E signals are the SCI port signals multiplexed with the GPIO signals.
There are two reserved and eight NC (not connected) signal pins.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-1
Signals/Connections
During Reset
MODA
MODB
MODC
MODD
RESET
DSP56321
VCCQL
VCCQH
VCCA
VCCD
VCCC
VCCH
VCCS
GND
5
3
3
4
2
2
66
EXTAL
XTAL
D[0–23]
AA[0–3]
RD
WR
TA
BR
BG
BB
Notes: 1.
2.
3.
Grounds
Clock
During After
Reset Reset
PINIT
NMI
A[0–17]
Power Inputs:
Core Logic
I/O
Address Bus
Data Bus
Bus Control
HI08
ESSI/SCI/Timer
DPLL
18
24
4
Port A
External
Address Bus
Interrupt/
Mode
Control
8
Host
Interface
(HI08)
Port1
After Reset
IRQA
IRQB
IRQC
IRQD
RESET
Non-Multiplexed Bus Multiplexed Bus
H[0–7]
HAD[0–7]
HA0
HAS/HAS
HA1
HA8
HA2
HA9
HCS/HCS
HA10
Double DS
Single DS
HRD/HRD
HRW
HDS/HDS
HWR/HWR
Single HR
Double HR
HREQ/HREQ
HTRQ/HTRQ
HACK/HACK
HRRQ/HRRQ
SC0[0–2]
SCK0
SRD0
STD0
Port C GPIO
PC[0–2]
PC3
PC4
PC5
SC1[0–2]
SCK1
SRD1
STD1
Port D GPIO
PD[0–2]
PD3
PD4
PD5
RXD
TXD
SCLK
Port E GPIO
PE0
PE1
PE2
Timers3
TIO0
TIO1
TIO2
Timer GPIO
TIO0
TIO1
TIO2
OnCE/
JTAG
Port
TCK
TDI
TDO
TMS
TRST
DE
Enhanced
Synchronous Serial
Interface Port 0
(ESSI0)2
3
Enhanced
Synchronous
Serial Interface
Port 1 (ESSI1)2
3
Serial
Communications
Interface (SCI)
Port2
External
Data Bus
External
Bus
Control
Port B GPIO
PB[0–7]
PB8
PB9
PB10
PB13
PB11
PB12
PB14
PB15
The HI08 port supports a non-multiplexed or a multiplexed bus, single or double Data Strobe (DS), and
single or double Host Request (HR) configurations. Since each of these modes is configured
independently, any combination of these modes is possible. These HI08 signals can also be configured
alternately as GPIO signals (PB[0–15]). Signals with dual designations (for example, HAS/HAS) have
configurable polarity.
The ESSI0, ESSI1, and SCI signals are multiplexed with the Port C GPIO signals (PC[0–5]), Port D
GPIO signals (PD[0–5]), and Port E GPIO signals (PE[0–2]), respectively.
TIO[0–2] can be configured as GPIO signals.
Figure 2-1. Signals Identified by Functional Group
DSP56321 Reference Manual, Rev. 1
2-2
Freescale Semiconductor
Power
2.1 Power
Table 2-2. Power Inputs
Power Name
Description
VCCQL
Quiet Core (Low) Power
An isolated power for the DSP56300 core processing logic. This input must be isolated externally from
all other chip power inputs.
VCCQH
Quiet External (High) Power
A quiet power source for I/O lines. This input must be tied externally to all other chip power inputs,
except VCCQL.
VCCA
Address Bus Power
An isolated power for sections of the address bus I/O drivers. This input must be tied externally to all
other chip power inputs, except VCCQL.
VCCD
Data Bus Power
An isolated power for sections of the data bus I/O drivers. This input must be tied externally to all other
chip power inputs, except VCCQL.
VCCC
Bus Control Power
An isolated power for the bus control I/O drivers. This input must be tied externally to all other chip
power inputs, except VCCQL.
VCCH
Host Power
An isolated power for the HI08 I/O drivers. This input must be tied externally to all other chip power
inputs, except VCCQL.
VCCS
ESSI, SCI, and Timer Power
An isolated power for the ESSI, SCI, and timer I/O drivers. This input must be tied externally to all other
chip power inputs, except VCCQL.
Note:
The user must provide adequate external decoupling capacitors for all power connections.
2.2 Ground
Table 2-3. Grounds
Ground
Name
GND
Note:
Description
Ground
Connected to an internal device ground plane.
The user must provide adequate external decoupling capacitors for all GND connections
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-3
Signals/Connections
2.3 Clock
Table 2-4. Clock Signals
Signal
Name
Type
State During
Reset
Signal Description
EXTAL
Input
Input
External Clock/Crystal Input
Interfaces the internal crystal oscillator input to an external crystal or an external clock.
XTAL
Output
Chip-driven
Crystal Output
Connects the internal crystal oscillator output to an external crystal. If an external clock
is used, leave XTAL unconnected.
2.4 PLL
Table 2-5. Digital Phase-Lock Loop Signals
Signal Name
Type
PINIT
Input
NMI
Input
State During
Reset
Input
Signal Description
PLL Initial
During assertion of RESET, the value of PINIT is written into the PLL
enable (PEN) bit of the PLL control (PCTL) register, determining
whether the PLL is enabled or disabled.
Nonmaskable Interrupt
After RESET deassertion and during normal instruction processing,
this Schmitt-trigger input is the negative-edge-triggered NMI request
internally synchronized to CLKOUT.
2.5 External Memory Expansion Port (Port A)
When the DSP56321 enters a low-power standby mode (stop or wait), it releases bus mastership
and tri-states the relevant port A signals: A[0–17], D[0–23], AA[0–3], RD, WR, and BB.
2.5.1 External Address Bus
Table 2-6. External Address Bus Signals
Signal Name
A[0–17]
Type
Output
State During
Reset
Tri-stated
Signal Description
Address Bus
When the DSP is the bus master, A[0–17] are active-high outputs
that specify the address for external program and data memory
accesses. Otherwise, the signals are tri-stated. To minimize power
dissipation, A[0–17] do not change state when external memory
spaces are not being accessed.
DSP56321 Reference Manual, Rev. 1
2-4
Freescale Semiconductor
External Memory Expansion Port (Port A)
2.5.2 External Data Bus
Table 2-7. External Data Bus Signals
Signal Name
D[0–23]
State During
Reset
Type
Input/ Output
Tri-stated
Signal Description
Data Bus
When the DSP is the bus master, D[0–23] are active-high,
bidirectional input/outputs that provide the bidirectional data bus for
external program and data memory accesses. Otherwise, D[0–23]
are tri-stated. These lines have weak keepers to maintain the last
state even if all drivers are tri-stated.
2.5.3 External Bus Control
Table 2-8. External Bus Control Signals
Signal Name
Type
State During
Reset, Stop,
or Wait
Signal Description
AA[0–3]
Output
Tri-stated
Address Attribute
These signals are used as chip selects or additional address lines. The default
use defines a priority scheme under which only one AA signal is asserted at a
time. Setting the AA priority disable (APD) bit (Bit 14) of the OMR disables the
priority mechanism and the lines are used together as four external lines
decoded externally into 16 chip select signals.
RD
Output
Tri-stated
Read Enable
When the DSP is the bus master, RD is asserted to read external memory on
the data bus (D[0–23]). Otherwise, RD is tri-stated.
WR
Output
Tri-stated
Write Enable
When the DSP is the bus master, WR is asserted to write external memory on
the data bus (D[0–23]). Otherwise, the signals are tri-stated.
TA
Input
Ignored Input
Transfer Acknowledge
If the DSP56321 is the bus master and there is no external bus activity, or the
DSP56321 is not the bus master, the TA input is ignored. The TA input is a
data transfer acknowledge (DTACK) function that can extend an external bus
cycle indefinitely. Any number of wait states (1, 2. . .infinity) can be added to
the wait states inserted by the bus control register (BCR) by keeping TA
deasserted. In typical operation, TA is deasserted at the start of a bus cycle, is
asserted to enable completion of the bus cycle, and is deasserted before the
next bus cycle. For correct operation, the TAS bit must be set in the Operating
Mode Register (OMR) to synchronize the TA signal with the internal clock.
The current bus cycle completes one clock period after TA is deasserted. The
number of wait states is determined by the TA input or by the BCR,
whichever is longer. The BCR sets the minimum number of wait states in
external bus cycles. To use the TA functionality, the BCR must be
programmed to at least one wait state. A zero wait state access cannot be
extended by TA deassertion.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-5
Signals/Connections
Table 2-8. External Bus Control Signals (Continued)
Signal Name
BR
Type
Output
State During
Reset, Stop,
or Wait
Reset: Output
(deasserted)
State during
Stop/Wait
depends on
BRH bit
setting:
Signal Description
Bus Request
Asserted when the DSP requests bus mastership. BR is deasserted when the
DSP no longer needs the bus. BR is asserted or deasserted independently of
whether the DSP56321 is a bus master or a bus slave. Bus “parking” allows
BR to be deasserted even though the DSP56321 is the bus master. (See the
description of bus “parking” in the BB signal description.) The Bus Request
Hold (BRH) bit in the BCR allows BR to be asserted under software control
even though the DSP does not need the bus. BR is typically sent to an
external bus arbitrator that controls the priority, parking, and tenure of each
master on the same external bus. BR is affected only by DSP requests for the
external bus, never for the internal bus. During hardware reset, BR is
deasserted and the arbitration is reset to the bus slave state.
The state during Stop/Wait depends on the BRH bit setting:
• BRH = 0: Output, deasserted
• BRH = 1: Maintains last state (that is, if asserted, remains asserted)
BG
Input
Ignored Input
Bus Grant
Asserted by an external bus arbitration circuit when the DSP56321 becomes
the next bus master. When BG is asserted, the DSP56321 must wait until BB
is deasserted before taking bus mastership. When BG is deasserted, bus
mastership is typically given up at the end of the current bus cycle. This may
occur in the middle of an instruction that requires more than one external bus
cycle for execution.
The default operation of this bit requires a setup and hold time as specified in
DSP56321 Technical Data (the data sheet). An alternate mode can be
invoked: set the asynchronous bus arbitration enable (ABE) bit (Bit 13) in the
OMR. When this bit is set, BG and BB are synchronized internally. This
eliminates the respective setup and hold time requirements but adds a
required delay between the deassertion of an initial BG input and the
assertion of a subsequent BG input.
BB
Input/
Output
Ignored input
Bus Busy
Indicates that the bus is active. Only after BB is deasserted can the pending
bus master become the bus master (and then assert the signal again). The
bus master can keep BB asserted after ceasing bus activity regardless of
whether BR is asserted or deasserted. Called “bus parking,” this allows the
current bus master to reuse the bus without rearbitration until another device
requires the bus. BB is deasserted by an “active pull-up” method (that is, BB is
driven high and then released and held high by an external pull-up resistor).
The default operation of this bit requires a setup and hold time as specified in
the DSP56321 Technical Data sheet. An alternate mode can be invoked: set
the ABE bit (Bit 13) in the OMR. When this bit is set, BG and BB are
synchronized internally. See BG for additional information.
BB requires an external pull-up resistor.
DSP56321 Reference Manual, Rev. 1
2-6
Freescale Semiconductor
Interrupt and Mode Control
2.6 Interrupt and Mode Control
The interrupt and mode control signals select the chip’s operating mode as it comes out of
hardware reset. After RESET is deasserted, these inputs are hardware interrupt request lines.
Table 2-9. Interrupt and Mode Control
Signal Name
Type
MODA
Input
IRQA
Input
MODB
Input
IRQB
Input
MODC
Input
State During
Reset
Input,
Schmitt-trigger
Input,
Schmitt-trigger
Input,
Schmitt-trigger
Input,
Schmitt-trigger
Input
Input
Mode Select C
MODA, MODB, MODC, and MODD select one of 16 initial chip operating
modes, latched into the OMR when the RESET signal is deasserted.
External Interrupt Request C
After reset, this input becomes a level-sensitive or
negative-edge-triggered, maskable interrupt request input during normal
instruction processing. If the processor is in the WAIT standby state and
IRQC is asserted, the processor exits the WAIT state.
Mode Select D
MODA, MODB, MODC, and MODD select one of 16 initial chip operating
modes, latched into the OMR when the RESET signal is deasserted.
External Interrupt Request D
After reset, this input becomes a level-sensitive or
negative-edge-triggered, maskable interrupt request input during normal
instruction processing. If the processor is in the WAIT standby state and
IRQD is asserted, the processor exits the WAIT state.
IRQD
RESET
Mode Select B
MODA, MODB, MODC, and MODD select one of 16 initial chip operating
modes, latched into the OMR when the RESET signal is deasserted.
External Interrupt Request B
After reset, this input becomes a level-sensitive or
negative-edge-triggered, maskable interrupt request input during normal
instruction processing. If the processor is in the WAIT standby state and
IRQB is asserted, the processor exits the WAIT state.
Input
Input
Mode Select A
MODA, MODB, MODC, and MODD select one of 16 initial chip operating
modes, latched into the OMR when the RESET signal is deasserted.
External Interrupt Request A
After reset, this input becomes a level-sensitive or
negative-edge-triggered, maskable interrupt request input during normal
instruction processing. If the processor is in the STOP or WAIT standby
state and IRQA is asserted, the processor exits the STOP or WAIT state.
IRQC
MODD
Signal Description
Input,
Schmitt-trigger
Reset
When asserted, places the chip in the Reset state and resets the internal
phase generator. The Schmitt-trigger input allows a slowly rising input
(such as a capacitor charging) to reset the chip reliably. When the
RESET signal is deasserted, the initial chip operating mode is latched
from the MODA, MODB, MODC, and MODD inputs. The RESET signal
must be asserted after power-up.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-7
Signals/Connections
2.7 HI08
The HI08 provides a fast, 8-bit, parallel data port that connects directly to the host bus. The HI08
supports a variety of standard buses and can directly connect to a number of industry-standard
microcomputers, microprocessors, DSPs, and DMA hardware.
Table 2-10. Host Interface
Signal Name
Type
H[0–7]
Input/Output
HAD[0–7]
Input/Output
PB[0–7]
State During
Reset1
Signal Description
Disconnected
internally
Host Data
When the HI08 is programmed to interface with a non-multiplexed host
bus and the HI function is selected, these signals are lines 0–7 of the Data
bus.
Host Address
When the HI08 is programmed to interface with a multiplexed host bus
and the HI function is selected, these signals are lines 0–7 of the
Address/Data bus.
Input or
Output
Port B 0–7
When the HI08 is configured as GPIO through the HPCR, these signals
are individually programmed through the HI08 Data Direction Register
(HDDR).
HA0
Input
HAS/HAS
Input
Disconnected
internally
Host Address Input 0
When the HI08 is programmed to interface with a non-multiplexed host
bus and the HI function is selected, this signal is line 0 of the Host
Address bus.
Host Address Strobe
When the HI08 is programmed to interface with a multiplexed host bus
and the HI function is selected, this signal is the Host Address Strobe
(HAS) Schmitt-trigger input. The polarity of the address strobe is
programmable, but is configured active-low (HAS) following reset.
PB8
Input or
Output
HA1
Input
HA8
Input
PB9
Input or
Output
Port B 8
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
Disconnected
internally
Host Address Input 1
When the HI08 is programmed to interface with a non-multiplexed host
bus and the HI function is selected, this signal is line 1 of the Host
Address bus.
Host Address 8
When the HI08 is programmed to interface with a multiplexed host bus
and the HI function is selected, this signal is line 8 of the Host Address
bus.
Port B 9
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
DSP56321 Reference Manual, Rev. 1
2-8
Freescale Semiconductor
HI08
Table 2-10. Host Interface (Continued)
Signal Name
Type
HA2
Input
HA9
Input
PB10
State During
Reset1
Disconnected
internally
Signal Description
Host Address Input 2
When the HI08 is programmed to interface with a non-multiplexed host
bus and the HI function is selected, this signal is line 2 of the Host
Address bus.
Host Address 9
When the HI08 is programmed to interface with a multiplexed host bus
and the HI function is selected, this signal is line 9 of the Host Address
bus.
Input or
Output
Port B 10
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
HRW
Input
HRD/HRD
Input
Disconnected
internally
Host Read/Write
When the HI08 is programmed to interface with a single-data-strobe host
bus and the HI function is selected, this signal is the Host Read/Write
input.
Host Read Data
When the HI08 is programmed to interface with a double-data-strobe host
bus and the HI function is selected, this signal is the Host Read Data
strobe (HRD) Schmitt-trigger input. The polarity of the data strobe is
programmable, but is configured as active-low (HRD) after reset.
PB11
Input or
Output
HDS/HDS
Input
HWR/HWR
Input
PB12
Input or
Output
Port B 11
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
Disconnected
internally
Host Data Strobe
When the HI08 is programmed to interface with a single-data-strobe host
bus and the HI function is selected, this signal is the Host Data Strobe
(HDS) Schmitt-trigger input. The polarity of the data strobe is
programmable, but is configured as active-low (HDS) following reset.
Host Write Data
When the HI08 is programmed to interface with a double-data-strobe host
bus and the HI function is selected, this signal is the Host Write Data
Strobe (HWR) Schmitt-trigger input. The polarity of the data strobe is
programmable, but is configured as active-low (HWR) following reset.
Port B 12
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-9
Signals/Connections
Table 2-10. Host Interface (Continued)
Signal Name
Type
HCS
Input
HA10
Input
PB13
State During
Signal Description
Reset1
Disconnected
internally
Host Chip Select
When the HI08 is programmed to interface with a non-multiplexed host
bus and the HI function is selected, this signal is the Host Chip Select
(HCS) input. The polarity of the chip select is programmable, but is
configured active-low (HCS) after reset.
Host Address 10
When the HI08 is programmed to interface with a multiplexed host bus
and the HI function is selected, this signal is line 10 of the Host Address
bus.
Input or
Output
Port B 13
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
HREQ/HREQ
Output
HTRQ/HTRQ
Output
Disconnected
internally
Host Request
When the HI08 is programmed to interface with a single host request host
bus and the HI function is selected, this signal is the Host Request
(HREQ) output. The polarity of the host request is programmable, but is
configured as active-low (HREQ) following reset. The host request can be
programmed as a driven or open-drain output.
Transmit Host Request
When the HI08 is programmed to interface with a double host request
host bus and the HI function is selected, this signal is the Transmit Host
Request (HTRQ) output. The polarity of the host request is
programmable, but is configured as active-low (HTRQ) following reset.
The host request may be programmed as a driven or open-drain output.
PB14
Input or
Output
Port B14
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
HACK/HACK
Input
HRRQ/HRRQ
Output
Receive Host Request
When the HI08 is programmed to interface with a double host request
host bus and the HI function is selected, this signal is the Receive Host
Request (HRRQ) output. The polarity of the host request is
programmable, but is configured as active-low (HRRQ) after reset. The
host request may be programmed as a driven or open-drain output.
PB15
Input or
Output
Port B 15
When the HI08 is configured as GPIO through the HPCR, this signal is
individually programmed through the HDDR.
Notes: 1.
2.
Disconnected
internally
Host Acknowledge
When the HI08 is programmed to interface with a single host request host
bus and the HI function is selected, this signal is the Host Acknowledge
(HACK) Schmitt-trigger input. The polarity of the host acknowledge is
programmable, but is configured as active-low (HACK) after reset.
In the Stop state, the signal maintains the last state as follows:
• If the last state is input, the signal is an ignored input.
• If the last state is output, the keeper circuit maintains the last output
level even if the internal driver is tri-stated.
The Wait processing state does not affect the signal state.
DSP56321 Reference Manual, Rev. 1
2-10
Freescale Semiconductor
Enhanced Synchronous Serial Interface 0
2.8 Enhanced Synchronous Serial Interface 0
Two synchronous serial interfaces (ESSI0 and ESSI1) provide a full-duplex serial port for serial
communication with a variety of serial devices, including one or more industry-standard codecs,
other DSPs, microprocessors, and peripherals which implement the serial peripheral interface
(SPI).
Table 2-11. Enhanced Synchronous Serial Interface 0 (ESSI0)
Signal
Name
SC00
Type
Input or Output
State During
Reset
Ignored input
PC0
Serial Control 0
Functions in either Synchronous or Asynchronous mode. For Asynchronous
mode, this signal is the receive clock I/O (Schmitt-trigger input). For
Synchronous mode, this signal is either for Transmitter 1 output or Serial I/O
Flag 0.
Port C 0
The default configuration following reset is GPIO. For PC0, signal direction
is controlled through the Port C Direction Register (PRRC). This signal is
configured as SC00 or PC0 through the Port C Control Register (PCRC).
SC01
Input/Output
PC1
Input or Output
SC02
Input/Output
PC2
Input or Output
SCK0
Input/Output
PC3
Signal Description
1, 2
Input or Output
Ignored input
Serial Control 1
Functions in either Synchronous or Asynchronous mode. For Asynchronous
mode, this signal is the receiver frame sync I/O. For Synchronous mode,
this signal is either Transmitter 2 output or Serial I/O Flag 1.
Port C 1
The default configuration following reset is GPIO. For PC1, signal direction
is controlled through PRRC. This signal is configured as SC01 or PC1
through PCRC.
Ignored input
Serial Control Signal 2
The frame sync for both the transmitter and receiver in Synchronous mode,
and for the transmitter only in Asynchronous mode. When configured as an
output, this signal is the internally generated frame sync signal. When
configured as an input, this signal receives an external frame sync signal for
the transmitter (and the receiver in synchronous operation).
Port C 2
The default configuration following reset is GPIO. For PC2, signal direction
is controlled through PRRC. This signal is configured as SC02 or PC2
through PCRC.
Ignored input
Serial Clock
Provides the serial bit rate clock for the ESSI interface for both the
transmitter and receiver in Synchronous modes, or the transmitter only in
Asynchronous modes. Although an external serial clock can be independent
of and asynchronous to the DSP system clock, it must exceed the minimum
clock cycle time of 6 T (that is, the system clock frequency must be at least
three times the external ESSI clock frequency). The ESSI needs at least
three DSP phases inside each half of the serial clock.
Port C 3
The default configuration following reset is GPIO. For PC3, signal direction
is controlled through PRRC. This signal is configured as SCK0 or PC3
through PCRC.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-11
Signals/Connections
Table 2-11. Enhanced Synchronous Serial Interface 0 (ESSI0) (Continued)
Signal
Name
Type
SRD0
Input
PC4
Input or Output
STD0
Output
PC5
Input or Output
Notes: 1.
2.
State During
Signal Description
Reset1, 2
Ignored input
Serial Receive Data
Receives serial data and transfers the data to the ESSI receive shift
register. SRD0 is an input when data is being received.
Port C 4
The default configuration following reset is GPIO. For PC4, signal direction
is controlled through PRRC. This signal is configured as SRD0 or PC4
through PCRC.
Ignored input
Serial Transmit Data
Transmits data from the serial transmit shift register. STD0 is an output
when data is being transmitted.
Port C 5
The default configuration following reset is GPIO. For PC5, signal direction
is controlled through PRRC. This signal is configured as STD0 or PC5
through PCRC.
In the Stop state, the signal maintains the last state as follows:
• If the last state is input, the signal is an ignored input.
• If the last state is output, the keeper circuit maintains the last output
level even if the internal driver is tri-stated.
The Wait processing state does not affect the signal state.
2.9 Enhanced Synchronous Serial Interface 1
Table 2-12. Enhanced Synchronous Serial Interface 1 (ESSI1)
Signal
Name
SC10
State During1
Type
Signal Description
Reset
Input or Output
Input
Stop
Disconnected
internally
PD0
Serial Control 0
Functions in either Synchronous or Asynchronous mode. For
Asynchronous mode, this signal is the receive clock I/O
(Schmitt-trigger input). For Synchronous mode, this signal is either
for Transmitter 1 output or Serial I/O Flag 0.
Port D 0
The default configuration following reset is GPIO. For PD0, signal
direction is controlled through the Port D Direction Register (PRRD).
This signal is configured as SC10 or PD0 through the Port D Control
Register (PCRD).
SC11
Input/Output
PD1
Input or Output
Input
Disconnected
internally
Serial Control 1
Functions in either Synchronous or Asynchronous mode. For
Asynchronous mode, this signal is the receiver frame sync I/O. For
Synchronous mode, this signal is either Transmitter 2 output or
Serial I/O Flag 1.
Port D 1
The default configuration following reset is GPIO. For PD1, signal
direction is controlled through PRRD. This signal is configured as
SC11 or PD1 through PCRD.
DSP56321 Reference Manual, Rev. 1
2-12
Freescale Semiconductor
Enhanced Synchronous Serial Interface 1
Table 2-12. Enhanced Synchronous Serial Interface 1 (ESSI1) (Continued)
Signal
Name
State During1
Type
SC12
Input/Output
PD2
Input or Output
SCK1
Input/Output
PD3
Input or Output
SRD1
Input
PD4
Input or Output
STD1
Output
PD5
Input or Output
Note:
Signal Description
Reset
Input
Stop
Disconnected
internally
Serial Control Signal 2
The frame sync for both the transmitter and receiver in Synchronous
mode, and for the transmitter only in Asynchronous mode. When
configured as an output, this signal is the internally generated frame
sync signal. When configured as an input, this signal receives an
external frame sync signal for the transmitter (and the receiver in
synchronous operation).
Port D 2
The default configuration following reset is GPIO. For PD2, signal
direction is controlled through PRRD. This signal is configured as
SC12 or PD2 through PCRD.
Input
Disconnected
internally
Serial Clock
Provides the serial bit rate clock for the ESSI interface for both the
transmitter and receiver in Synchronous modes, or the transmitter
only in Asynchronous modes. Although an external serial clock can
be independent of and asynchronous to the DSP system clock, it
must exceed the minimum clock cycle time of 6 T (that is, the
system clock frequency must be at least three times the external
ESSI clock frequency). The ESSI needs at least three DSP phases
inside each half of the serial clock.
Port D 3
The default configuration following reset is GPIO. For PD3, signal
direction is controlled through PRRD. This signal is configured as
SCK1 or PD3 through PCRD.
Input
Disconnected
internally
Serial Receive Data
Receives serial data and transfers the data to the ESSI receive shift
register. SRD0 is an input when data is being received.
Port D 4
The default configuration following reset is GPIO. For PD4, signal
direction is controlled through PRRD. This signal is configured as
SRD1 or PD4 through PCRD.
Input
Disconnected
internally
Serial Transmit Data
Transmits data from the serial transmit shift register. STD1 is an
output when data is being transmitted.
Port C 5
The default configuration following reset is GPIO. For PD5, signal
direction is controlled through PRRD. This signal is configured as
STD1 or PD5 through PCRD.
The Wait processing state does not affect the signal state.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-13
Signals/Connections
2.10 SCI
The SCI provides a full duplex port for serial communication to other DSPs, microprocessors, or
peripherals such as modems.
Table 2-13. Serial Communication Interface (SCI)
Signal
Name
State During1
Type
Reset
RXD
Input
PE0
Input or
Output
TXD
Output
PE1
Input or
Output
SCLK
Input/Output
PE2
Input or
Output
Note:
Signal Description
Input
Stop
Disconnected
internally
Serial Receive Data
Receives byte-oriented serial data and transfers it to the SCI
receive shift register.
Port E 0
The default configuration following reset is GPIO. When configured
as PE0, signal direction is controlled through the Port E Directions
Register (PRRE). This signal is configured as RXD or PE0 through
the Port E Control Register (PCRE).
Input
Disconnected
internally
Serial Transmit Data
Transmits data from SCI transmit data register.
Port E 1
The default configuration following reset is GPIO. When configured
as PE1, signal direction is controlled through the SCI PRRE. This
signal is configured as TXD or PE1 through PCRE.
Input
Disconnected
internally
Serial Clock
Provides the input or output clock used by the transmitter and/or the
receiver.
Port E 2
The default configuration following reset is GPIO. For PE2, signal
direction is controlled through the SCI PRRE. This signal is
configured as SCLK or PE2 through PCRE.
The Wait processing state does not affect the signal state.
DSP56321 Reference Manual, Rev. 1
2-14
Freescale Semiconductor
Timers
2.11 Timers
Three identical and independent timers are implemented in the DSP56321. Each timer can use
internal or external clocking and can either interrupt the DSP56321 after a specified number of
events (clocks) or signal an external device after counting a specific number of internal events.
Table 2-14. Triple Timer Signals
Signal
Name
State During1
Type
Reset
Stop
Signal Description
TIO0
Input or
Output
Input
Disconnected
internally
Timer 0 Schmitt-Trigger Input/Output
As an external event counter or in Measurement mode, TIO0 is
input. In Watchdog, Timer, or Pulse Modulation mode, TIO0 is
output. The default mode after reset is GPIO input. This can be
changed to output or configured as a Timer Input/Output through
the Timer 0 Control/Status Register (TCSR0).
TIO1
Input or
Output
Input
Disconnected
internally
Timer 1 Schmitt-Trigger Input/Output
As an external event counter or in Measurement mode, TIO1 is
input. In Watchdog, Timer, or Pulse Modulation mode, TIO1 is
output. The default mode after reset is GPIO input. This can be
changed to output or configured as a Timer Input/Output through
the Timer 1 Control/Status Register (TCSR1).
TIO2
Input or
Output
Input
Disconnected
internally
Timer 2 Schmitt-Trigger Input/Output
As an external event counter or in Measurement mode, TIO2 is
input. In Watchdog, Timer, or Pulse Modulation mode, TIO2 is
output. The default mode after reset is GPIO input. This can be
changed to output or configured as a Timer Input/Output through
the Timer 2 Control/Status Register (TCSR2).
Note:
The Wait processing state does not affect the signal state.
2.12 JTAG and OnCE Interface
The DSP56300 family and in particular the DSP56321 support circuit-board test strategies that
are based on the IEEE 1149.1 Standard Test Access Port and Boundary Scan Architecture, the
industry standard developed under the sponsorship of the Test Technology Committee of IEEE
and the JTAG. The OnCE module provides a means to interface nonintrusively with the
DSP56300 core and its peripherals so that you can examine registers, memory, or on-chip
peripherals. Functions of the OnCE module are provided through the JTAG TAP signals. For
programming models, see the chapter on debugging support in the DSP56300 Family Manual.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
2-15
Signals/Connections
Table 2-15. OnCE/JTAG Interface
Type
State
During
Reset
TCK
Input
Input
Test Clock
A test clock input signal to synchronize the JTAG test logic.
TDI
Input
Input
Test Data Input
A test data serial input signal used for test instructions and data. TDI is sampled on
the rising edge of TCK and has an internal pull-up resistor.
TDO
Output
Tri-stated
Test Data Output
A test data serial output signal for test instructions and data. TDO is tri-statable and
is actively driven in the shift-IR and shift-DR controller states. TDO changes on the
falling edge of TCK.
TMS
Input
Input
Test Mode Select
Sequences the test controller’s state machine. TMS is sampled on the rising edge of
TCK and has an internal pull-up resistor.
TRST
Input
Input
Test Reset
Initializes the test controller asynchronously. TRST has an internal pull-up resistor.
TRST must be asserted after power up.
Input/
Output
Input
Debug Event
As an input, provides a means of entering debug mode from an external command
controller. As an output, provides a means of acknowledging that the chip has
entered debug mode. Asserted as an input, DE causes the DSP56300 core to finish
executing the current instruction, save the instruction pipeline information, enter
debug mode, and wait for commands from the debug serial input line. This signal is
asserted as an output for three clock cycles when the chip enters debug mode as a
result of a debug request or a breakpoint condition. The DE has an internal pull-up
resistor.
Signal
Name
DE
Signal Description
DE is not a standard part of the JTAG TAP controller. The signal connects directly to
the OnCE module to initiate debug mode directly or to provide a direct external
indication that the chip has entered debug mode. All other interaction with the OnCE
module must occur through the JTAG port.
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Memory Configuration
3
Like all members of the DSP56300 core family, the DSP56321 can address three sets of
16 M × 24-bit memory internally: program, X data, and Y data. Each of these memory spaces
includes both on-chip and external memory (accessed through the external memory interface).
The DSP56321 is extremely flexible because it has several modes to allocate on-chip memory
between the program memory and the two data memory spaces. Section 3.1 provides a general
description of the program memory space. Section 3.2 and Section 3.3 describe the X and Y data
memory spaces. Section 3.4 summarizes the available memory configurations. Section 3.5
provides guidelines for changing the memory configuration dynamically.
3.1 Program Memory Space
Program memory space consists of the following:
„
„
„
„
Note:
Internal program memory (program RAM, 32 K by default, up to 112 K)
(Optional) instruction cache (1 K) taken from internal program RAM
Bootstrap program ROM (192 × 24-bit)
Optional off-chip memory expansion (as much as 64 K in 16-bit mode or 256 K in 24-bit
mode using the 18 external address lines). Refer to the DSP56300 Family Manual,
especially the Expansion Port chapter, for detailed information on using the external
memory interface to access external program memory.
Program memory space at locations $FF00C0–$FFFFFF is reserved and should not be
accessed.
3.1.1 Internal Program Memory
The default on-chip program memory consists of a 24-bit-wide, high-speed, SRAM occupying
the lowest 32 K locations ($0–$7FFF) in program memory space. The on-chip program RAM is
organized in 32 banks with 1024 locations each. You can make additional program memory
available using the memory switch mode described in Section 3.1.2, Memory Switch
Modes—Program Memory.
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3-1
Memory Configuration
3.1.2 Memory Switch Modes—Program Memory
Memory switch mode allows reallocation of portions of X and Y data RAM as program RAM.
OMR[22, 21, and 7] are the memory switch (MSW[2–0]) bits that control this function. When
MSW[2–0] = 000, program memory consists of the default 32 K × 24-bit memory space
described in the previous section. In this default mode, the lowest external program memory
location is $8000. When MSW[2–0] ≠ 000, portions of the X and Y data memory are reallocated
to the program memory (see Section 3.4 for details). In any of the Memory Switch modes, if the
instruction cache is enabled (that is, if the CE bit in the Status Register is set), the lowest 1 K
internal program words (locations $0–$3FF) are used as cache memory. With the cache enabled,
the lowest 1 K of internal program memory is inaccessible and the address range is redirected to
external program memory.
Note:
When using an enabled instruction cache, do not use the vector address bus to access
any address between P:$0–$3FF. (See the memory maps, starting with Figure 3-1 on
page -7.)
3.1.3 Program Bootstrap ROM
The program memory space occupying locations $FF0000–$FF00BF includes the internal
bootstrap ROM. This ROM contains the 192-word DSP56321 bootstrap program.
3.2 X Data Memory Space
The X data memory space consists of the following:
„
„
„
Note:
Internal X data memory (80 K by default down to 40 K)
Internal X I/O space (upper 128 locations)
Optional off-chip memory expansion (as much as 64 K in 16-bit mode, or 256 K in 24-bit
mode using the 18 external address lines). Refer to the DSP56300 Family Manual,
especially Section 2, Expansion Port, for details on using the external memory interface to
access external X data memory.
Do not access the reserved X memory space at locations $FF0000–$FFEFFF.
3.2.1 Internal X Data Memory
The default on-chip X data RAM is a 24-bit-wide, internal, static memory occupying the lowest
80 K locations ($0–$13FFF) in X memory space. The on-chip X data RAM is organized into 80
banks with 1024 locations each. Available X data memory space can be reallocated to program
memory using the memory switch mode described in the next section.
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Freescale Semiconductor
Y Data Memory Space
3.2.2 Memory Switch Modes—X Data Memory
Memory switch mode reallocates of portions of X and Y data RAM as program RAM. OMR[22,
21, and 7] are the memory switch (MSW[2–0]) bits that control this function. When MSW[2–0]
= 000, X data memory consists of the default 80 K × 24-bit memory space described in the
previous section. In this default mode, the lowest external program memory location is $14000.
When MSW[2–0] ≠ 000, portions of the X and Y data memory are reallocated to the program
memory (see Section 3.4 for details).
Note:
The 12 K lowest locations ($0–$2FFF) of internal X memory are shared memory
accessible by both the core and EFCOP. The EFCOP connects to the shared memory
instead of the DMA bus, so the DMA cannot access shared memory. Simultaneous
core and EFCOP accesses to the same shared memory bank (1024 locations) are not
permitted. The programmer must prevent simultaneous accesses.
3.2.3 Internal X I/O Space
One part of the on-chip peripheral registers and some of the DSP56321 core registers occupy the
top 128 locations of the X data memory ($FFFF80–$FFFFFF). This area is referred to as the
internal X I/O space and it can be accessed by MOVE, MOVEP instructions and by bit-oriented
instructions (BCHG, BCLR, BSET, BTST, BRCLR, BRSET, BSCLR, BSSET, JCLR, JSET,
JSCLR and JSSET). Appendix B lists the internal X I/O memory contents.
3.3 Y Data Memory Space
The Y data memory space consists of the following:
„
„
„
„
Note:
Internal Y data memory (80 K by default down to 40 K)
Internal Y I/O space (16 locations at $FFFF80–$FFFF8F)
External Y I/O space (upper 112 locations)
Optional off-chip memory expansion (up to 64 K in 16-bit mode or 256 K in 24-bit mode
using the 18 external address lines). Refer to the DSP56300 Family Manual for details on
using the external memory interface to access external Y data memory.
Do not access the reserved Y memory space at locations $FF0000–$FFEFFF.
3.3.1 Internal Y Data Memory
The default on-chip Y data RAM is a 24-bit-wide, internal, static memory occupying the lowest
80 K locations ($0–$13FFF) in Y memory space. The on-chip Y data RAM is organized in 24
banks, 1024 locations each. Available Y data memory space is reduced and reallocated to
program memory by using the memory switch mode described in the following paragraphs.
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3-3
Memory Configuration
3.3.2 Memory Switch Modes—Y Data Memory
Memory switch mode reallocates of portions of X and Y data RAM as program RAM. OMR[22,
21, and 7] are the memory switch (MSW[2–0]) bits that control this function. When MSW[2–0]
= 000, Y data memory consists of the default 80 K × 24-bit memory space described in the
previous section. In this default mode, the lowest external program memory location is $14000.
When MSW[2–0] ≠ 000, portions of the X and Y data memory are reallocated to the program
memory (see Section 3.4 for details).
Note:
The 12 K lowest locations ($0–$2FFF) of internal Y memory are shared memory
accessible by both the core and EFCOP. The EFCOP connects to the shared memory
instead of the DMA bus, so the DMA cannot access shared memory. Simultaneous
core and EFCOP accesses to the same shared memory bank (1024 locations) are not
permitted. The programmer must prevent simultaneous accesses.
3.3.3 Internal Y I/O Space
The second part of the on-chip peripheral registers occupies 9 locations ($FFFFB0–$FFFFB8) of
the Y data memory and contains the registers supporting the EFCOP. This area is the internal
Y I/O space, and it can be accessed by MOVE, MOVEP instructions and by bit-oriented
instructions (BCHG, BCLR, BSET, BTST, BRCLR, BRSET, BSCLR, BSSET, JCLR, JSET,
JSCLR and JSSET). The contents of the internal Y I/O memory space are listed in Appendix B.
3.3.4 External Y I/O Space
Off-chip peripheral registers should be mapped into the top 64 locations ($FFFFC0–$FFFFFF) to
take advantage of the move peripheral data (MOVEP) instruction and the bit-oriented
instructions (BCHG, BCLR, BSET, BTST, BRCLR, BRSET, BSCLR, BSSET, JCLR, JSET,
JSCLR and JSSET). This area is the external Y I/O space.
3.4 Summary of Memory Switch Mode Configurations
Table 3-1 summarizes the various combinations of memory switch modes and instruction cache
.
Table 3-1. DSP56321 Switch Memory Configuration
Program RAM
Size
Instruction
Cache Size
X Data RAM
Size*
Y Data RAM
Size*
Instruction
Cache (CE)
MSW2
MSW1
MSW0
32 K × 24-bit
0
80 K × 24-bit
80 K × 24-bit
disabled
0
0
0
31 K × 24-bit
1024 × 24-bit
80 K × 24-bit
80 K × 24-bit
enabled
0
0
0
40 K × 24-bit
0
76 K × 24-bit
76 K × 24-bit
disabled
0
0
1
39 K × 24-bit
1024 × 24-bit
76 K × 24-bit
76 K × 24-bit
enabled
0
0
1
48 K × 24-bit
0
72 K × 24-bit
72 K × 24-bit
disabled
0
1
0
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Dynamic Memory Configuration Switching
Table 3-1. DSP56321 Switch Memory Configuration (Continued)
Program RAM
Size
Instruction
Cache Size
X Data RAM
Size*
Y Data RAM
Size*
Instruction
Cache (CE)
MSW2
MSW1
MSW0
47 K × 24-bit
1024 × 24-bit
72 K × 24-bit
72 K × 24-bit
enabled
0
1
0
64 K × 24-bit
0
64 K × 24-bit
64 K × 24-bit
disabled
0
1
1
63 K × 24-bit
1024 × 24-bit
64 K × 24-bit
64 K × 24-bit
enabled
0
1
1
72 K × 24-bit
0
60 K × 24-bit
60 K × 24-bit
disabled
1
0
0
71 K × 24-bit
1024 × 24-bit
60 K × 24-bit
60 K × 24-bit
enabled
1
0
0
80 K × 24-bit
0
56 K × 24-bit
56 K × 24-bit
disabled
1
0
1
79 K × 24-bit
1024 × 24-bit
56 K × 24-bit
56 K × 24-bit
enabled
1
0
1
96 K × 24-bit
0
48 K × 24-bit
48 K × 24-bit
disabled
1
1
0
95 K × 24-bit
1024 × 24-bit
48 K × 24-bit
48 K × 24-bit
enabled
1
1
0
112 K × 24-bit
0
40 K × 24-bit
40 K × 24-bit
disabled
1
1
1
111 K × 24-bit
1024 × 24-bit
40 K × 24-bit
40 K × 24-bit
enabled
1
1
1
*Includes 12 K × 24-bit shared memory (that is, memory shared by the DSP56300 core and the EFCOP)
3.5 Dynamic Memory Configuration Switching
When the internal memory configuration is altered by remapping RAM modules from X and Y
data memories into program memory space and vice versa, data contents of the switched RAM
modules are preserved. Any sequence that complies with the switch condition is valid. For
example, if the program flow executes in the address range that is not affected by the switch, the
switch condition can be met very easily. A switch can be accomplished just by changing the
OMR[MS/MSW] bits in the regular program flow, assuming no accesses to the affected address
ranges of the data memory occur up to three instructions after the instruction that changes the
OMR bits.
CAUTION
To ensure that dynamic switching is trouble-free, do not allow any
accesses (including instruction fetches) to or from the affected
address ranges in program and data memories during the switch cycle.
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Freescale Semiconductor
3-5
Memory Configuration
Because an interrupt could cause the DSP to fetch instructions out of sequence and might violate
the switch condition, special care should be taken in relation to the interrupt vector routines.
CAUTION
Pay special attention when executing a memory switch routine using
the OnCE port. Running the switch routine in trace mode, for
example, can cause the switch to complete after the MSW bits change
while the DSP is in Debug mode. As a result, subsequent instructions
may be fetched according to the new memory configuration (after the
switch) and thus may execute improperly.
3.6 Sixteen-Bit Compatibility Mode Configuration
The sixteen-bit compatibility (SC) mode allows the DSP56321 to use DSP56000 object code
without change. The SC bit (Bit 13 in the SR) is used to switch from the default 24-bit mode to
this special 16-bit mode. SC is cleared by reset. You must set this bit to select the SC mode. The
address ranges described in the previous sections apply in the SC mode with regard to the
reallocation of X and Y data memory to program memory in MS mode, but the maximum
addressing ranges are limited to $FFFF, and all data and program code are 16 bits wide. Refer to
the memory maps in the following section for details about internal memory allocation in
Sixteen-Bit Compatibility Mode.
3.7 Memory Maps
The following figures illustrate each of the memory space and RAM configurations defined by
the settings of the MSW[2–0], CE, and SC bits. The figures show the configuration and describe
the bit settings, memory sizes, and memory locations.
Note:
In 16-bit mode, if MSW[2–0] ≠ 000, very little external program memory is accessible,
so enabling the instruction cache is of little benefit. In addition, certain 16-bit modes
prevent you from accessing the entire internal DSP56321 memory space.
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Memory Maps
DEFAULT
Program
$FFFFFF
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
Internal
Reserved
$FFF000
External
$FFF000
Internal
Reserved
$FF00C0
External
$014000
$008000
Internal
Program RAM
32 K
MS2 MS1 MS0
0
Note:
0
0
Internal I/O
External
$FF0000
External
$014000
Internal
X data RAM
80 K
$000000
Bit Settings
External I/O
Internal
Reserved
$FF0000 Bootstrap ROM $FF0000
$000000
$FFFFC0
$FFFF80
External
Internal
Y data RAM
80 K
$000000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
32 K
$0000–$7FFF
80 K
$0000–$13FFF
80 K
$0000–$13FFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-1. MSW[2–0] = 000, Cache Off, 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-7
Memory Configuration
Program
X Data
Y Data
$FFFFFF
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
Internal
Reserved
$FFF000
External
$FFF000
Internal
Reserved
$FF00C0
External
$014000
$008000
Internal
Program RAM
31 K
$000400
External
$000000
$000000
Bit Settings
0
Note:
0
0
External I/O
Internal I/O
External
Internal
Reserved
$FF0000 Bootstrap ROM $FF0000
MS2 MS1 MS0
$FFFFC0
$FFFF80
$FF0000
External
$014000
Internal
X data RAM
80 K
External
Internal
Y data RAM
80 K
$000000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
0
31 K
$0400–$7FFF
80 K
$0000–$13FFF
80 K
$0000–$13FFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-2. MSW[2–0] = 000, Cache On, 24-Bit Mode
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Memory Maps
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
$FFF000
Internal
Reserved
$FF00C0
$FF0000
External
$FFFFFF
$FFFFC0
$FFFF80
Bootstrap ROM
Internal I/O
External
Internal
Reserved
$FF0000
$FF0000
External
External
External I/O
External
$013000
$013000
$00A000
Internal
Program RAM
40 K
$000000
Internal
X data RAM
76 K
$000000
Bit Settings
MS2 MS1 MS0
0
Note:
0
1
Internal
Y data RAM
76 K
$000000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
40 K
$0000–$9FFF
76 K
$0000–$12FFF
76 K
$0000–$12FFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-3. MSW[2–0] = 001, Cache Off, 24-Bit Mode
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3-9
Memory Configuration
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
$FFF000
Internal
Reserved
$FF00C0
$FF0000
External
$FFFFFF
$FFFFC0
$FFFF80
Bootstrap ROM
External I/O
Internal I/O
External
Internal
Reserved
$FF0000
$FF0000
External
External
External
$013000
$013000
$00A000
Internal
Program RAM
39 K
$000400
External
$000000
$000000
Bit Settings
MS2 MS1 MS0
0
Note:
0
1
Internal
X data RAM
76 K
Internal
Y data RAM
76 K
$000000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
0
39 K
$0400–$9FFF
76 K
$0000–$12FFF
76 K
$0000–$12FFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-4. MSW[2–0] = 001, Cache On, 24-Bit Mode
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Memory Maps
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
$FFF000
Internal
Reserved
$FF00C0
$FF0000
External
$FFFFFF
$FFFFC0
$FFFF80
Bootstrap ROM
Internal I/O
External
Internal
Reserved
$FF0000
$FF0000
External
External
External I/O
External
$012000
$012000
$00C000
Internal
Program RAM
48 K
$000000
Internal
X data RAM
72 K
$000000
Bit Settings
MS2 MS1 MS0
0
Note:
1
0
Internal
Y data RAM
72 K
$000000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
48 K
$0000–$BFFF
72 K
$0000–$11FFF
72 K
$0000–$11FFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-5. MSW[2–0] = 010, Cache Off, 24-Bit Mode
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3-11
Memory Configuration
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
$FFF000
Internal
Reserved
$FF00C0
$FF0000
External
$FFFFFF
$FFFFC0
$FFFF80
Bootstrap ROM
External I/O
Internal I/O
External
Internal
Reserved
$FF0000
$FF0000
External
External
External
$012000
$00C000
Internal
Program RAM
47 K
$000400
External
$000000
$000000
Bit Settings
MS2 MS1 MS0
0
Note:
1
0
$012000
Internal
X data RAM
72 K
Internal
Y data RAM
72 K
$000000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
0
47 K
$0400–$BFFF
72 K
$0000–$11FFF
72 K
$0000–$11FFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-6. MSW[2–0] = 010, Cache On, 24-Bit Mode
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Memory Maps
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
Bootstrap ROM
External
Internal
Program RAM
64K
0
Note:
1
1
External
Internal
Y data RAM
64 K
Internal
X data RAM
64 K
Bit Settings
External
$010000
$000000
$000000
Internal I/O
$FF0000
$010000
$010000
External I/O
Internal
Reserved
$FF0000
External
MS2 MS1 MS0
$FFF000
Internal
Reserved
$FF00C0
$FF0000
External
$FFFFFF
$FFFFC0
$FFFF80
$000000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
64 K
$0000–$FFFF
64 K
$0000–$FFFF
64 K
$0000–$FFFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-7. MSW[2–0] = 011, Cache Off, 24-Bit Mode
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3-13
Memory Configuration
Program
X Data
$FFFFFF
Y Data
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
Bootstrap ROM
External
Internal
Program RAM
63 K
External
MS2 MS1 MS0
0
Note:
1
1
External
$010000
Internal
X data RAM
64 K
$000000
Bit Settings
Internal I/O
External
$FF0000
$010000
$010000
External I/O
Internal
Reserved
$FF0000
External
$000400
$000000
$FFF000
Internal
Reserved
$FF00C0
$FF0000
External
$FFFFFF
$FFFFC0
$FFFF80
Internal
Y data RAM
64 K
$000000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
0
63 K
$0400–$FFFF
64 K
$0000–$FFFF
64 K
$0000–$FFFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-8. MSW[2–0] = 011, Cache On 24-Bit Mode
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Memory Maps
Program
X Data
$FFFFFF
Y Data
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
$FFF000
Bootstrap ROM
Internal I/O
External
$FF0000
$FF0000
External
External I/O
Internal
Reserved
Internal
Reserved
$FF00C0
$FF0000
External
$FFFFFF
$FFFFC0
$FFFF80
External
External
$012000
$00F000
$00F000
Internal
Program RAM
72 K
$000000
1
Note:
0
0
$000000
$000000
Bit Settings
MS2 MS1 MS0
Internal
Y data RAM
60 K
Internal
X data RAM
60 K
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
72 K
$0000–$11FFF
60 K
$0000–$EFFF
60 K
$0000–$EFFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-9. MSW[2–0] = 100, Cache Off, 24-Bit Mode
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3-15
Memory Configuration
Program
X Data
$FFFFFF
Y Data
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
External
$FFFFFF
$FFFFC0
$FFFF80
$FFF000
Bootstrap ROM
$FF0000
External
$FF0000
$FF0000
External
Internal I/O
Internal
Reserved
Internal
Reserved
$FF00C0
External I/O
External
External
$012000
$00F000
$00F000
Internal
Program RAM
71 K
$000400
$000000
External
1
Note:
0
0
$000000
$000000
Bit Settings
MS2 MS1 MS0
Internal
Y data RAM
60 K
Internal
X data RAM
60 K
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
0
71 K
$0400–$11FFF
60 K
$0000–$EFFF
60 K
$0000–$EFFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-10. MSW[2–0] = 100, Cache On 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
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Freescale Semiconductor
Memory Maps
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
External
$FFFFFF
$FFFFC0
$FFFF80
$FFF000
Bootstrap ROM
$FF0000
Internal I/O
External
Internal
Reserved
Internal
Reserved
$FF00C0
External I/O
$FF0000
$FF0000
External
External
$014000
$00E000
Internal
Program RAM
80 K
Bit Settings
MS2 MS1 MS0
1
Note:
0
1
$00E000
Internal
Y data RAM
56 K
Internal
X data RAM
56 K
$000000
$000000
$000000
External
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
80 K
$0000–$13FFF
56 K
$0000–$DFFF
56 K
$0000–$DFFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-11. MSW[2–0] = 101, Cache Off, 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-17
Memory Configuration
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
External
$FFFFFF
$FFFFC0
$FFFF80
$FFF000
Bootstrap ROM
$FF0000
Internal I/O
External
Internal
Reserved
Internal
Reserved
$FF00C0
External I/O
$FF0000
$FF0000
External
External
$014000
$00E000
Internal
Program RAM
79 K
$000400
$000000
External
MS2 MS1 MS0
1
Note:
0
1
$00E000
Internal
Y data RAM
56 K
Internal
X data RAM
56 K
$000000
$000000
Bit Settings
External
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
0
79 K
$0400–$13FFF
56 K
$0000–$DFFF
56 K
$0000–$DFFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-12. MSW[2–0] = 101, Cache On, 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-18
Freescale Semiconductor
Memory Maps
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
External
$FFFFFF
$FFFFC0
$FFFF80
$FFF000
Bootstrap ROM
$FF0000
Internal I/O
External
Internal
Reserved
Internal
Reserved
$FF00C0
External I/O
$FF0000
$FF0000
External
$018000
External
Internal
Program RAM $00C000
96 K
$000000
$000000
Bit Settings
MS2 MS1 MS0
1
Note:
1
0
External
$00C000
Internal
X data RAM
48 K
$000000
Internal
Y data RAM
48 K
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
96 K
$0000–$17FFF
48 K
$0000–$BFFF
48 K
$0000–$BFFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-13. MSW[2–0] = 110, Cache Off, 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-19
Memory Configuration
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
External
$FFFFFF
$FFFFC0
$FFFF80
$FFF000
Bootstrap ROM
$FF0000
Internal I/O
External
Internal
Reserved
Internal
Reserved
$FF00C0
External I/O
$FF0000
$FF0000
External
$018000
External
Internal
Program RAM $00C000
95 K
$000400
$000000
External
$000000
Bit Settings
MS2 MS1 MS0
1
Note:
1
0
External
$00C000
Internal
X data RAM
48 K
$000000
Internal
Y data RAM
48 K
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
0
0
95 K
$0400–$17FFF
48 K
$0000–$BFFF
48 K
$0000–$BFFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-14. MSW[2–0] = 110, Cache On, 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-20
Freescale Semiconductor
Memory Maps
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
External
$FFFFFF
$FFFFC0
$FFFF80
$FFF000
Bootstrap ROM
$FF0000
Internal I/O
External
Internal
Reserved
Internal
Reserved
$FF00C0
External I/O
$FF0000
$FF0000
External
$01C000
External
Internal
Program RAM $00A000
112 K
$000000
$000000
Bit Settings
MS2 MS1 MS0
1
Note:
1
1
External
$00A000
Internal
X data RAM
40 K
$000000
Internal
Y data RAM
40 K
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
0
112 K
$0000–$1BFFF
40 K
$0000–$9FFF
40 K
$0000–$9FFF
None
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-15. MSW[2–0] = 111, Cache Off, 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-21
Memory Configuration
Program
X Data
Y Data
$FFFFFF
$FFFFFF
Internal I/O
$FFFF80
$FFF000
Internal
Reserved
External
$FFFFFF
$FFFFC0
$FFFF80
$FFF000
Bootstrap ROM
$FF0000
Internal I/O
External
Internal
Reserved
Internal
Reserved
$FF00C0
External I/O
$FF0000
$FF0000
External
$01C000
External
Internal
Program RAM $00A000
111 K
$000400
$000000
External
$000000
Bit Settings
MS2 MS1 MS0
1
Note:
1
1
External
$00A000
Internal
X data RAM
40 K
$000000
Internal
Y data RAM
40 K
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
0
111 K
$0400–$1BFFF
40 K
$0000–$9FFF
40 K
$0000–$9FFF
1 K internal
not accessible
16 M
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-16. MSW[2–0] = 111, Cache On, 24-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-22
Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FC00
External
$FFFF
$FFC0
$FF80
$FC00
External I/O
Internal I/O
External
External
$8000
Internal
Y data RAM
63 K
Internal
X data RAM
63 K
Internal
Program RAM
32 K
$0000
$0000
Bit Settings
MS2 MS1 MS0
0
Note:
0
0
$0000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
32 K
$0000–$7FFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-17. MSW[2–0] = 000, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-23
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FC00
External
$FFFF
$FFC0
$FF80
$FC00
External I/O
Internal I/O
External
External
$8000
Internal
Y data RAM
63 K
Internal
X data RAM
63 K
Internal
Program RAM
32 K
$0400
$0000
External
$0000
Bit Settings
MS2 MS1 MS0
0
Note:
0
0
$0000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
31 K
$0400–$7FFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-18. MSW[2–0] = 000, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-24
Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
External
$FC00
External
$FFFF
$FFC0
$FF80
$FC00
External I/O
Internal I/O
External
$A000
Internal
Y data RAM
63 K
Internal
X data RAM
63 K
Internal
Program RAM
40 K
$0000
$0000
Bit Settings
MS2 MS1 MS0
0
Note:
0
1
$0000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
40 K
$0000–$9FFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-19. MSW[2–0] = 001, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-25
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FC00
External
$FFFF
$FFC0
$FF80
$FC00
External I/O
Internal I/O
External
External
$A000
Internal
Y data RAM
63K
Internal
X data RAM
63 K
Internal
Program RAM
39 K
$0400
$0000
External
$0000
Bit Settings
MS2 MS1 MS0
0
Note:
0
1
$0000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
39 K
$0400–$9FFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-20. MSW[2–0] = 001, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
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Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
External
$FC00
External
$FFFF
$FFC0
$FF80
$FC00
External I/O
Internal I/O
External
$C000
Internal
Y data RAM
63 K
Internal
X data RAM
63 K
Internal
Program RAM
48 K
$0000
$0000
Bit Settings
MS2 MS1 MS0
0
Note:
1
0
$0000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
48 K
$0000–$BFFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-21. MSW[2–0] = 010, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-27
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
External
$FC00
External
$FFFF
$FFC0
$FF80
$FC00
External I/O
Internal I/O
External
$C000
Internal
Y data RAM
24 K
Internal
X data RAM
24 K
Internal
Program RAM
47 K
$0400
$0000
External
$0000
Bit Settings
MS2 MS1 MS0
0
Note:
1
0
$0000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
47 K
$0400–$BFFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-22. MSW[2–0] = 010, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-28
Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FC00
Internal
Program RAM
64 K
Bit Settings
0
Note:
1
1
$FC00
External I/O
Internal I/O
External
Internal
Y data RAM
63 K
Internal
X data RAM
63 K
$0000
$0000
MS2 MS1 MS0
External
$FFFF
$FFC0
$FF80
$0000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
64 K
$0000–$FFFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-23. MSW[2–0] = 011, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-29
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FC00
Internal
Program RAM
63 K
$0400
$0000
External
0
Note:
1
1
$FC00
$0000
External I/O
Internal I/O
External
Internal
Y data RAM
63 K
Internal
X data RAM
63 K
Bit Settings
MS2 MS1 MS0
External
$FFFF
$FFC0
$FF80
$0000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
63 K
$0400–$FFFF
63 K
$0000–$FBFF
63 K
$0000–$FBFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-24. MSW[2–0] = 011, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-30
Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
1
Note:
0
0
Internal
Y data RAM
60 K
Internal
X data RAM
60 K
Bit Settings
MS2 MS1 MS0
$F000
$0000
$0000
Internal I/O
External
$F000
Internal
Program RAM
64 K
External I/O
$0000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
64 K
$0000–$FFFF
60 K
$0000–$EFFF
60 K
$0000–$EFFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-25. MSW[2–0] = 100, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-31
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
$0400
$0000
External
MS2 MS1 MS0
1
Note:
0
0
$F000
Internal
Y data RAM
60 K
Internal
X data RAM
60 K
$0000
Bit Settings
Internal I/O
External
$F000
Internal
Program RAM
63 K
External I/O
$0000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
63 K
$0400–$FFFF
60 K
$0000–$EFFF
60 K
$0000–$EFFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-26. MSW[2–0] = 100, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-32
Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
$0000
$E000
MS2 MS1 MS0
1
Note:
0
1
Internal
Y data RAM
56 K
Internal
X data RAM
56 K
$0000
$0000
Bit Settings
Internal I/O
External
$E000
Internal
Program RAM
64 K
External I/O
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
64 K
$0000–$FFFF
56 K
$0000–$DFFF
56 K
$0000–$DFFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-27. MSW[2–0] = 101, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-33
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
$0400
$0000
External
$E000
MS2 MS1 MS0
1
Note:
0
1
Internal
Y data RAM
56 K
Internal
X data RAM
56 K
$0000
$0000
Bit Settings
Internal I/O
External
$E000
Internal
Program RAM
63 K
External I/O
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
63 K
$0400–$FFFF
56 K
$0000–$DFFF
56 K
$0000–$DFFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-28. MSW[2–0] = 101, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-34
Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
External I/O
Internal I/O
External
$C000
$C000
Internal
Program RAM
64 K
Internal
Y data RAM
48 K
Internal
X data RAM
48 K
Bit Settings
MS2 MS1 MS0
1
Note:
1
0
$0000
$0000
$0000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
64 K
$0000–$FFFF
48 K
$0000–$BFFF
48 K
$0000–$BFFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-29. MSW[2–0] = 110, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-35
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
External I/O
Internal I/O
External
$C000
$C000
Internal
Program RAM
63 K
Internal
Y data RAM
48 K
Internal
X data RAM
48 K
$0400
$0000
External
$0000
Bit Settings
MS2 MS1 MS0
1
Note:
1
0
$0000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
63 K
$0400–$FFFF
48 K
$0000–$BFFF
48 K
$0000–$BFFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-30. MSW[2–0] = 110, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
3-36
Freescale Semiconductor
Memory Maps
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
External I/O
Internal I/O
External
$A000
$A000
Internal
Program RAM
64 K
Internal
Y data RAM
40 K
Internal
X data RAM
40 K
$0000
$0000
Bit Settings
MS2 MS1 MS0
1
Note:
1
1
$0000
Internal Memory Configuration
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
Addressable
Memory Size
0
1
64 K
$0000–$FFFF
40 K
$0000–$9FFF
40 K
$0000–$9FFF
None
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-31. MSW[2–0] = 111, Cache Off, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
3-37
Memory Configuration
Program
X Data
$FFFF
$FFFF
Y Data
Internal I/O
$FF80
$FFFF
$FFC0
$FF80
External
External I/O
Internal I/O
External
$A000
$A000
Internal
Program RAM
63 K
Internal
Y data RAM
40 K
Internal
X data RAM
40 K
$0400
$0000
External
$0000
Bit Settings
MS2 MS1 MS0
1
Note:
1
1
$0000
Internal Memory Configuration
Addressable
Memory Size
CE
SC
Program RAM
X Data RAM
Y Data RAM
Cache
1
1
63 K
$0400–$FFFF
40 K
$0000–$9FFF
40 K
$0000–$9FFF
1 K internal
not accessible
64 K
Lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory accessible by the core and EFCOP but
not by the DMA controller.
Figure 3-32. MSW[2–0] = 111, Cache On, 16-Bit Mode
DSP56321 Reference Manual, Rev. 1
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Freescale Semiconductor
Core Configuration
4
This chapter presents DSP56300 core configuration details specific to the DSP56321. These
configuration details include the following:
„
„
„
„
„
„
„
„
„
Operating modes
Bootstrap program
Central Processor registers
— Status register (SR)
— Operating mode register (OMR)
Interrupt Priority Registers (IPRC and IPRP)
Bus Interface Unit registers
— Bus Control Register (BCR)
— Address Attribute Registers (AAR[3–0])
DMA Control Registers 5–0 (DCR[5–0])
Device identification register (IDR)
JTAG identification register
JTAG boundary scan register (BSR)
For information on specific registers or modules in the DSP56300 core, refer to the DSP56300
Family Manual.
4.1 Operating Modes
The DSP56321 begins operation by leaving the Reset state and going into one of eight operating
modes. As the DSP56321 exits the Reset state, it loads the values of MODA, MODB, MODC,
and MODD into bits MA, MB, MC, and MD of the OMR. These bit settings determine the chip’s
operating mode, which in turn determines the bootstrap program option the chip uses to start up.
Software can also directly set the OMR[MA–MD] bits. A jump directly to the bootstrap program
entry point ($FF0000) after the OMR bits are set causes the DSP56321 to execute the specified
bootstrap program option (except modes 0 and 8). Table 4-1 shows the DSP56321 bootstrap
operation modes, the corresponding settings of the external operational mode signal lines (the
OMR[MA–MD] bits), and the reset vector address to which the DSP56321 jumps once it leaves
the Reset state.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-1
Core Configuration
Table 4-1. DSP56321 Operating Modes
Reset
Vector
Mode
MODD
MODC
MODB
MODA
Description
0
0
0
0
0
$C00000
Expanded mode
Bypasses the bootstrap ROM, and the DSP56321
starts fetching instructions beginning at address
$C00000. Memory accesses are performed using
SRAM memory access type with 31 wait states and no
address attributes selected (default). Address
$C00000 is reflected as address $00000 on Port A
signals A[0–17].
1
0
0
0
1
$FF0000
Reserved
2
0
0
1
0
$FF0000
Reserved
3
0
0
1
1
$FF0000
Reserved
4
0
1
0
0
$FF0000
Reserved
5
0
1
0
1
$FF0000
Reserved
6
0
1
1
0
$FF0000
Reserved
7
0
1
1
1
$FF0000
Reserved
8
1
0
0
0
$008000
Expanded mode
Bypasses the bootstrap ROM, and the DSP56321
starts fetching instructions beginning at address
$008000. Memory accesses are performed using
SRAM memory access type with 31 wait states and no
address attributes selected.
9
1
0
0
1
$FF0000
Bootstrap from byte-wide memory
The bootstrap program loads instructions through Port
A from external byte-wide memory, starting at
P:$D00000. The SRAM memory access type is
selected by the values in address attribute register 1
(AAR1). Thirty-one wait states are inserted between
each memory access. Address $D00000 is reflected
as address $00000 on Port A signals A[0–17]. The
boot program concatenates every 3 bytes read from
the external memory into a 24-bit wide DSP56321
word.
A
1
0
1
0
$FF0000
Bootstrap through SCI
Instructions are loaded through the SCI. The bootstrap
program sets the SCI to operate in 10-bit
asynchronous mode, with 1 start bit, 8 data bits, 1 stop
bit, and no parity. Data is received in this order: start
bit, 8 data bits (LSB first), and one stop bit. Data is
aligned in the SCI receive data register with the LSB of
the least significant byte of the received data appearing
at Bit 0.The user must provide an external clock source
with a frequency at least 16 times the transmission
data rate. Each byte received by the SCI is echoed
back through the SCI transmitter to the external
transmitter. The boot program concatenates every 3
bytes read from the SCI into a 24-bit wide DSP56321
word.
B
1
0
1
1
$FF0000
Reserved
DSP56321 Reference Manual, Rev. 1
4-2
Freescale Semiconductor
Bootstrap Program
Table 4-1. DSP56321 Operating Modes (Continued)
Reset
Vector
Description
Mode
MODD
MODC
MODB
MODA
C
1
1
0
0
$FF0000
HI08 bootstrap in ISA/DSP563xx mode
The HI08 is configured to interface with an ISA bus or
with the memory expansion port of a master DSP563xx
processor through the HI08. The HI08 pin configuration
is optimized for connection to the ISA bus or memory
expansion port of a master DSP based on the
DSP56300 core.
D
1
1
0
1
$FF0000
HI08 bootstrap in HC11 nonmultiplexed mode
The bootstrap program sets the host interface to
interface with the Freescale HC11 microcontroller
through the HI08. The HI08 pin configuration is
optimized for connection to the Freescale HC11
nonmultiplexed bus.
E
1
1
1
0
$FF0000
HI08 bootstrap in 8051 multiplexed bus mode
The bootstrap program sets the host interface to
interface with the Intel 8051 bus through the HI08. The
program stored in this location, after testing MODA,
MODB, MODC, and MODD, bootstraps through HI08.
The HI08 pin configuration is optimized for connection
to the Intel 8051 multiplexed bus.
F
1
1
1
1
$FF0000
HI08 bootstrap in MC68302 bus mode
The bootstrap program sets the host interface to
interface with the Freescale MC68302 or MC68360
bus through the HI08. The HI08 pin configuration is
optimized for connection to a Freescale MC68302 or
MC68360 bus.
4.2 Bootstrap Program
The bootstrap program is factory-programmed in an internal 192-word by 24-bit bootstrap ROM
located in program memory space at locations $FF0000–$FF00BF. The bootstrap program can
load any program RAM segment from an external byte-wide EPROM, the SCI, or the host port.
The bootstrap program code is listed in Appendix A. Upon exiting the Reset state, the DSP56321
samples the MOD[A–D] signal lines and loads their values into OMR[MA–MD]. The mode
input signals (MOD[A–D]) and the resulting MA, MB, MC, and MD bits determine which
bootstrap mode the DSP56321 enters (see Table 4-1).
Note:
To stop the bootstrap in any HI08 bootstrap mode, set the Host Flag 0 (HF0). The
loaded user program begins executing from the specified starting address.
You can invoke the bootstrap program options (except modes 0 and 8) at any time by setting the
MA, MB, MC, and MD bits in the OMR and jumping to the bootstrap program entry point,
$FF0000. Software can directly set the mode selection bits in the OMR. Bootstrap modes 0 and 8
are the normal DSP56321 functioning modes. Bootstrap modes 9, A, and C–F select different
specific bootstrap loading source devices.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-3
Core Configuration
In these modes, the bootstrap program expects the following data sequence when downloading
the user program through an external port:
1.
Three bytes that specify the number of (24-bit) program words to be loaded
2.
Three bytes that specify the (24-bit) start address where the user program loads in the
DSP56321 program memory
3.
The user program (three bytes for each 24-bit program word)
The three bytes for each data sequence are loaded least significant byte first. When the bootstrap
program finishes loading the specified number of words, it jumps to the specified starting address
and executes the loaded program.
4.3 Central Processor Unit (CPU) Registers
There are two CPU registers that must be configured to initialize operation. The Status Register
(SR) selects various arithmetic processing protocols and contains several status reporting flag
bits. The Operating Mode Register (OMR) configures several system operating modes and
characteristics.
4.3.1 Status Register (SR)
The Status Register (SR) (Figure 4-1) is a 24-bit register that indicates the current system state of
the processor and the results of previous arithmetic computations. The SR is pushed onto the
system stack when program looping is initialized or a JSR is performed, including long
interrupts. The SR consists of the following three special-purpose 8-bit control registers:
„
„
Extended Mode Register (EMR) (SR[23–16]) and Mode Register (MR) (SR[15–8]). These
special-purpose registers define the current system state of the processor. The bits in both
registers are affected by hardware reset, exception processing, ENDDO (end current DO
loop) instructions, RTI (return from interrupt) instructions, and TRAP instructions. In
addition, the EMR bits are affected by instructions that specify SR as their destination (for
example, DO FOREVER instructions, BRKcc instructions, and MOVEC). During
hardware reset, all EMR bits are cleared. The MR register bits are affected by DO
instructions, and instructions that directly reference the MR (for example, ANDI, ORI, or
instructions, such as MOVEC, that specify SR as the destination). During processor reset,
the interrupt mask bits are set and all other bits are cleared.
Condition Code Register (CCR) (SR[7–0]). Defines the results of previous arithmetic
computations. The CCR bits are affected by Data Arithmetic Logic Unit (Data ALU)
operations, parallel move operations, instructions that directly reference the CCR (for
example, ORI and ANDI), and instructions that specify SR as a destination (for example,
MOVEC). Parallel move operations affect only the S and L bits of the CCR. During
processor reset, all CCR bits are cleared.
DSP56321 Reference Manual, Rev. 1
4-4
Freescale Semiconductor
Central Processor Unit (CPU) Registers
The definition of the three 8-bit registers within the SR is primarily for the purpose of
compatibility with other Freescale DSPs. Bit definitions in the following paragraphs identify the
bits within the SR and not within the subregister.
Extended Mode Register (EMR)
23
22
21
20
19
18
CP[1–0] RM SM CE
Mode Register (MR)
17
16
15
14
13
SA
FV
LF DM SC
0
0
12
11
10
Condition Code Register (CCR)
9
8
7
6
5
4
3
2
1
0
S[1–0]
I[1–0]
S
L
E
U
N
Z
V
C
0
1
0
0
0
0
0
0
0
0
Reset:
1
1
0
0
0
0
0
0
0
0
0
1
Reserved bit. Read as zero; write to zero for future compatibility
Figure 4-1. Status Register (SR)
Table 4-2. Status Register Bit Definitions
Bit Number
Bit Name
Reset Value
Description
23–22
CP[1–0]
11
Core Priority
Under control of the CDP[1–0] bits in the OMR, the CP bits specify the priority
of core accesses to external memory. These bits are compared against the
priority bits of the active DMA channel. If the core priority is greater than the
DMA priority, the DMA waits for a free time slot on the external bus. If the core
priority is less than the DMA priority, the core waits for a free time slot on the
external bus. If the core priority equals the DMA priority, the core and DMA
access the external bus in a round robin pattern (for example, ... P, X, Y, DMA,
P, X, Y, ...).
Priority
Mode
Core
Priority
DMA
Priority
OMR
(CDP[1-0])
SR (CP[1–0])
Dynamic
0
(Lowest)
Determined
by DCRn
(DPR[1–0])
for active
DMA
channel
00
00
00
01
00
10
00
11
core < DMA
01
xx
core = DMA
10
xx
core > DMA
11
xx
1
2
3
(Highest)
Static
21
RM
0
Rounding Mode
Selects the type of rounding performed by the Data ALU during arithmetic
operations. If RM is cleared, convergent rounding is selected. If RM is set,
two’s-complement rounding is selected.
20
SM
0
Arithmetic Saturation Mode
Selects automatic saturation on 48 bits for the results going to the
accumulator. This saturation is performed by a special circuit inside the MAC
unit. The purpose of this bit is to provide an Arithmetic Saturation mode for
algorithms that do not recognize or cannot take advantage of the extension
accumulator.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-5
Core Configuration
Table 4-2. Status Register Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
19
CE
0
Cache Enable
Enables/disables the instruction cache controller. If CE is set, the cache is
enabled, and instructions are cached into and fetched from the internal
Program RAM. If CE is cleared, the cache is disabled and the DSP56300 core
fetches instructions from external or internal program memory, according to
the memory space table of the specific DSP56300 core-based device.
Note:
18
To ensure proper operation, do not clear Cache Enable mode while
Burst mode is enabled (OMR[BE] is set).
0
Reserved. Write to zero for future compatibility.
17
SA
0
Sixteen-Bit Arithmetic Mode
Affects data width functionality, enabling the Sixteen-bit Arithmetic mode of
operation. When SA is set, the core uses 16-bit operations instead of 24-bit
operations. In this mode, 16-bit data is right-aligned in the 24-bit memory
locations, registers, and 24-bit register portions. Shifting, limiting, rounding,
arithmetic instructions, and moves are performed accordingly. For details on
Sixteen-Bit Arithmetic mode, consult the DSP56300 Family Manual.
16
FV
0
DO FOREVER Flag
Set when a DO FOREVER loop executes. The FV flag, like the LF flag, is
restored from the stack when a DO FOREVER loop terminates. Stacking and
restoring the FV flag when initiating and exiting a DO FOREVER loop,
respectively, allow program loops to be nested. When returning from the long
interrupt with an RTI instruction, the system stack is pulled and the value of the
FV bit is restored.
15
LF
0
Do Loop Flag
When a program loop is in progress, enables the detection of the end of the
loop. The LF is restored from stack when a program loop terminates. Stacking
and restoring the LF when initiating and exiting a program loop, respectively,
allow program loops to be nested. When returning from the long interrupt with
an RTI instruction, the System Stack is pulled and the LF bit value is restored.
14
DM
0
Double-Precision Multiply Mode
Enables four multiply/MAC operations to implement a double-precision
algorithm that multiplies two 48-bit operands with a 96-bit result. Clearing the
DM bit disables the mode.
Note:
The Double-Precision Multiply mode is supported to maintain object
code compatibility with devices in the DSP56000 family. For a more
efficient way of executing double precision multiply, refer to the
chapter on the Data Arithmetic Logic Unit in the DSP56300 Family
Manual.
In Double-Precision Multiply mode, the behavior of the four specific operations
listed in the double-precision algorithm is modified. Therefore, do not use
these operations (with those specific register combinations) in
Double-Precision Multiply mode for any purpose other than the double
precision multiply algorithm. All other Data ALU operations (or the four listed
operations, but with other register combinations) can be used.
The double-precision multiply algorithm uses the Y0 Register at all stages.
Therefore, do not change Y0 when running the double-precision multiply
algorithm. If the Data ALU must be used in an interrupt service routine, Y0
should be saved with other Data ALU registers to be used and restored before
the interrupt routine terminates.
DSP56321 Reference Manual, Rev. 1
4-6
Freescale Semiconductor
Central Processor Unit (CPU) Registers
Table 4-2. Status Register Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
13
SC
0
Sixteen-Bit Compatibility Mode
Affects addressing functionality, enabling full compatibility with object code
written for the DSP56000 family. When SC is set, MOVE operations to/from
any of the following PCU registers clear the eight MSBs of the destination: LA,
LC, SP, SSL, SSH, EP, SZ, VBA and SC. If the source is either the SR or
OMR, then the eight MSBs of the destination are also cleared. If the
destination is either the SR or OMR, then the eight MSBs of the destination
are left unchanged. To change the value of one of the eight MSBs of the SR or
OMR, clear SC.
SC also affects the contents of the Loop Counter Register. If SC is cleared
(normal operation), then a loop count value of zero causes the loop body to be
skipped, and a loop count value of $FFFFFF causes the loop to execute the
maximum number of 224 – 1 times. If the SC bit is set, a loop count value of
zero causes the loop to execute 216 times, and a loop count value of $FFFFFF
causes the loop to execute 216 – 1 times.
Note:
12
11–10
S[1–0]
Due to pipelining, a change in the SC bit takes effect only after three
instruction cycles. Insert three NOP instructions after the instruction
that changes the value of this bit to ensure proper operation.
0
Reserved. Write to 0 for future compatibility.
0
Scaling Mode
Specify the scaling to be performed in the Data ALU shifter/limiter and the
rounding position in the Data ALU MAC unit. The Shifter/limiter Scaling mode
affects data read from the A or B accumulator registers out to the X-data bus
(XDB) and Y-data bus (YDB). Different scaling modes can be used with the
same program code to allow dynamic scaling. One application of dynamic
scaling is to facilitate block floating-point arithmetic. The scaling mode also
affects the MAC rounding position to maintain proper rounding when different
portions of the accumulator registers are read out to the XDB and YDB.
Scaling mode bits are cleared at the start of a long Interrupt Service Routine
and during a hardware reset.
S1
S0
Scaling
Mode
Rounding Bit
SEquation
0
0
No scaling
23
S = (A46 XOR A45)
OR (B46 XOR B45)
OR S (previous)
0
1
Scale down
24
S = (A47 XOR A46)
OR (B47 XOR B46)
OR S (previous)
1
0
Scale up
22
S = (A45 XOR A44)
OR (B45 XOR B44)
OR S (previous)
1
1
Reserved
—
S undefined
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-7
Core Configuration
Table 4-2. Status Register Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
9–8
I[1–0]
11
Interrupt Mask
Reflect the current Interrupt Priority Level (IPL) of the processor and indicate
the IPL needed for an interrupt source to interrupt the processor. The current
IPL of the processor can be changed under software control. The interrupt
mask bits are set during hardware reset, but not during software reset.
Priority
I1
I0
Exceptions
Permitted
Lowest
0
0
IPL 0, 1, 2, 3
None
0
1
IPL 1, 2, 3
IPL 0
1
0
IPL 2, 3
IPL 0, 1
1
1
IPL 3
IPL 0, 1, 2
Highest
Exceptions Masked
7
S
0
Scaling
Set when a result moves from accumulator A or B to the XDB or YDB buses
(during an accumulator to memory or accumulator to register move) and
remains set until explicitly cleared; that is, the S bit is a sticky bit. The logical
equations of this bit are dependent on the Scaling mode. The scaling bit is set
if the absolute value in the accumulator, before scaling, is > 0.25 or < 0.75.
6
L
0
Limit
Set if the overflow bit is set or if the data shifter/limiter circuits perform a
limiting operation. In Arithmetic Saturation mode, the L bit is also set when an
arithmetic saturation occurs in the Data ALU result; otherwise, it is not
affected. The L bit is cleared only by a processor reset or by an instruction that
specifically clears it (that is, a sticky bit); this allows the L bit to be used as a
latching overflow bit. The L bit is affected by data movement operations that
read the A or B accumulator registers.
5
E
1
Extension
Cleared if all the bits of the integer portion of the 56-bit result are all ones or all
zeros; otherwise, this bit is set. The Scaling mode defines the integer portion.
If the E bit is cleared, then the low-order fraction portion contains all the
significant bits; the high-order integer portion is sign extension. In this case,
the accumulator extension register can be ignored. If the E bit is set, it
indicates that the accumulator extension register is in use.
4
U
0
S1
S0
Scaling Mode
Integer Portion
0
0
No scaling
Bits 55–47
0
1
Scale down
Bits 55–48
1
0
Scale up
Bits 5–46
1
1
Reserved
Undefined
Unnormalized
Set if the two MSBs of the Most Significant Portion (MSP) of the result are
identical; otherwise, this bit is cleared. The MSP portion of the A or B
accumulators is defined by the Scaling mode.
S1
S0
Scaling Mode
Integer Portion
0
0
No scaling
U = (Bit 47 XOR Bit 46)
0
1
Scale down
U = (Bit 48 XOR Bit 47)
1
0
Scale up
U = (Bit 46 XOR Bit 45)
1
1
Reserved
U undefined
DSP56321 Reference Manual, Rev. 1
4-8
Freescale Semiconductor
Central Processor Unit (CPU) Registers
Table 4-2. Status Register Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
3
N
0
Negative
Set if the MSB of the result is set; otherwise, this bit is cleared.
2
Z
0
Zero
Set if the result equals zero; otherwise, this bit is cleared.
1
V
0
Overflow
Set if an arithmetic overflow occurs in the 56-bit result; otherwise, this bit is
cleared. V indicates that the result cannot be represented in the accumulator
register (that is, the register overflowed). In Arithmetic Saturation mode, an
arithmetic overflow occurs if the Data ALU result is not representable in the
accumulator without the extension part (that is, 48-bit accumulator or the 32-bit
accumulator in Arithmetic Sixteen-bit mode).
0
C
0
Carry
Set if a carry is generated by the MSB resulting from an addition operation.
This bit is also set if a borrow is generated in a subtraction operation;
otherwise, this bit is cleared. The carry or borrow is generated from Bit 55 of
the result. The C bit is also affected by bit manipulation, rotate, and shift
instructions.
4.3.2 Operating Mode Register (OMR)
The OMR is a read/write register divided into three byte-sized units. The lowest two bytes (EOM
and COM) control the chip’s operating mode. The high byte (SCS) controls and monitors the
stack extension. The OMR control bits are shown in Figure 4-2.
Stack Control/Status (SCS)
23
22
21
20
19
18
17
Extended Operating Mode (EOM)
16
15
MSW[2–1] SEN WRP EOV EUN XYS
14
13
12
11
10
APD ABE BRT TAS BE
9
Chip Operating Mode (COM)
8
7
6
5
CDP[1–0] MSW0 SD
4
3
2
1
0
EBD MD MC MB MA
Reset:
0
*
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
*
*
*
*
After reset, these bits reflect the corresponding value of the mode input (that is, MODD, MODC, MODB, or MODA, respectively).
Reserved bit. Read as zero; write to zero for future compatibility
The Enhanced Operating Mode (EOM) and Chip Operating Mode (COM) bytes are affected only
by processor reset and by instructions directly referencing the OMR (that is, ANDI, ORI, and
other instructions, such as MOVEC, that specify OMR as a destination). The Stack
Control/Status (SCS) byte is referenced implicitly by some instructions, such as DO, JSR, and
RTI, or directly by the MOVEC instruction. During processor reset, the chip operating mode bits
(MD, MC, MB, and MA) are loaded from the external mode select pins MODD, MODC,
MODB, and MODA respectively. Table 4-3 defines the DSP56321 OMR bits.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-9
Core Configuration
Table 4-3. Operating Mode Register (OMR) Bit Definitions
Bit Number
Bit Name
23
22–21
MSW[2–1]
Reset Value
Description
0
Reserved. Write to 0 for future compatibility.
0
Memory Switch Mode Bits 2, 1
Used with bit 7 (MSW0), the three bits configure the internal memory sizes
for Program, X-data, and Y-data memory. See Table 3-1 for details.
Notes: 1.
2.
To ensure proper operation, place six NOP instructions after
the instruction that changes the MSW bits.
To ensure proper operation, do not change the MSW bits
while the Instruction Cache is enabled (SR[CE] bit is set).
19
WRP
0
Stack Extension Wrap Flag
Set when copying from the on-chip hardware stack (System Stack Register
file) to the stack extension memory begins. You can use this flag during the
debugging phase of the software development to evaluate and increase the
speed of software-implemented algorithms. The WRP flag is a sticky bit
(that is, cleared only by hardware reset or by an explicit MOVEC operation
to the OMR).
18
EOV
0
Stack Extension Overflow Flag
Set when a stack overflow occurs in Stack Extended mode. Extended stack
overflow is recognized when a push operation is requested while SP = SZ
(Stack Size register), and the Extended mode is enabled by the SEN bit.
The EOV flag is a sticky bit (that is, cleared only by hardware reset or by an
explicit MOVEC operation to the OMR). The transition of the EOV flag from
zero to one causes a Priority Level 3 (Non-maskable) stack error exception.
17
EUN
0
Stack Extension Underflow Flag
Set when a stack underflow occurs in Extended Stack mode. Extended
stack underflow is recognized when a pull operation is requested, SP = 0,
and the SEN bit enables Extended mode. The EUN flag is a sticky bit (that
is, cleared only by hardware reset or by an explicit MOVEC operation to the
OMR). Transition of the EUN flag from zero to one causes a Priority Level 3
(Non-maskable) stack error exception.
Note:
16
15
XYS
While the chip is in Extended Stack mode, the UF bit in the SP
acts like a normal counter bit.
0
Stack Extension XY Select
Determines whether the stack extension is mapped onto X or Y memory
space. If the bit is clear, then the stack extension is mapped onto the X
memory space. If the XYS bit is set, the stack extension is mapped to the Y
memory space.
0
Reserved. Write to 0 for future compatibility.
DSP56321 Reference Manual, Rev. 1
4-10
Freescale Semiconductor
Central Processor Unit (CPU) Registers
Table 4-3. Operating Mode Register (OMR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
14
APD
0
Address Attribute Priority Disable
Disables the priority assigned to the Address Attribute signals (AA[0–3]).
When APD = 0 (default setting), the four Address Attribute signals each
have a certain priority: AA3 has the highest priority, AA0 has the lowest
priority. Therefore, only one AA signal can be active at one time. This
allows continuous partitioning of external memory; however, certain
functions, such as using the AA signals as additional address lines, require
the use of additional interface hardware. When APD is set, the priority
mechanism is disabled, allowing more than one AA signal to be active
simultaneously. Therefore, the AA signals can be used as additional
address lines without the need for additional interface hardware. For details
on the Address Attribute Registers, see Section 4.5.2, Address Attribute
Registers (AAR[0–3]), on page 4-20.
13
ABE
0
Asynchronous Bus Arbitration Enable
Eliminates the setup and hold time requirements for BB and BG, and
substitutes a required non-overlap interval between the deassertion of one
BG input to a DSP56300 family device and the assertion of a second BG
input to a second DSP56300 family device on the same bus. When the ABE
bit is set, the BG and BB inputs are synchronized. This synchronization
causes a delay between a change in BG or BB until this change is actually
accepted by the receiving device.
12
BRT
0
Bus Release Timing
Selects between fast or slow bus release. If BRT is cleared, a Fast Bus
Release mode is selected (that is, no additional cycles are added to the
access and BB is not guaranteed to be the last Port A pin that is tri-stated at
the end of the access). If BRT is set, a Slow Bus Release mode is selected
(that is, an additional cycle is added to the access, and BB is the last Port A
pin that is tri-stated at the end of the access).
11
TAS
0
TA Synchronize Select
Selects the synchronization method for the input Port A pin—TA (Transfer
Acknowledge). For correct operation if TA is used, TAS must be set to
synchronize the TA signal with the internal clock.
10
BE
0
Cache Burst Mode Enable
Enables/disables Burst mode in the memory expansion port during an
instruction cache miss. If the bit is cleared, Burst mode is disabled and only
one program word is fetched from the external memory when an instruction
cache miss condition is detected. If the bit is set, Burst mode is enabled,
and up to four program words are fetched from the external memory when
an instruction cache miss is detected.
9–8
CDP[1–0]
11
Core-DMA Priority
Specify the priority of core and DMA accesses to the external bus.
7
MS
0
00
Determined by comparing status register CP[1–0] to the
active DMA channel priority
01
DMA accesses have higher priority than core accesses
10
DMA accesses have the same priority as the core accesses
11
DMA accesses have lower priority than the core accesses
Memory Switch Mode Bit 0
Used with bits 22–21 (MSW[2–1]). See bits 22–21 for details.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-11
Core Configuration
Table 4-3. Operating Mode Register (OMR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
6
SD
0
Stop Delay Mode
Determines the length of the delay invoked when the core exits the Stop
state. The STOP instruction suspends core processing indefinitely until a
defined event occurs to restart it. If SD is cleared, a 128K clock cycle delay
is invoked before a STOP instruction cycle continues. However, if SD is set,
the delay before the instruction cycle continues is 16 clock cycles. The long
delay allows a clock stabilization period for the internal clock to begin
oscillating and to stabilize. When a stable external clock is used, the shorter
delay allows faster start-up of the DSP56300 core.
0
Reserved. Write to zero for future compatibility.
5
4
EBD
0
External Bus Disable
Disables the external bus controller to reduce power consumption when
external memories are not used. When EBD is set, the external bus
controller is disabled and external memory cannot be accessed. When EBD
is cleared, the external bus controller is enabled and external access can
be performed. Hardware reset clears the EBD bit.
3–0
MD–MA
*
Chip Operating Mode
Indicate the operating mode of the DSP56300 core. On hardware reset,
these bits are loaded from the external mode select pins, MODD, MODC,
MODB, and MODA, respectively. After the DSP56300 core leaves the
Reset state, MD–MA can be changed under program control.
* The MD–MA bits reflect the corresponding value of the mode input (that is, MODD–MODA), respectively.
4.4 Configuring Interrupts
DSP56321 interrupt handling, like that for all DSP56300 family members, is optimized for DSP
applications. Refer to the sections describing interrupts in Chapter 2, Core Architecture
Overview, in the DSP56300 Family Manual. Two registers are used to configure the interrupt
characteristics:
„
„
Interrupt Priority Register-Core (IPRC)—Programmed to configure the priority levels for
the core DMA interrupts and the external interrupt lines as well as the interrupt line trigger
modes
Interrupt Priority Register-Peripherals (IPRP)—Programmed to configure the priority
levels for the interrupts used with the on-chip peripheral devices
The interrupt table resides in the 256 locations of program memory to which the PCU vector base
address (VBA) register points. These locations store the starting instructions of the interrupt
handler for each specified interrupt. The memory is programmed by the bootstrap program at
startup.
DSP56321 Reference Manual, Rev. 1
4-12
Freescale Semiconductor
Configuring Interrupts
4.4.1 Interrupt Priority Registers (IPRC and IPRP)
There are two interrupt priority registers in the DSP56321. The IPRC (Figure 4-3) is dedicated to
DSP56300 core interrupt sources, and IPRP (Figure 4-4) is dedicated to DSP56321 peripheral
interrupt sources.
22
23
D5L1
21
D5L0
D4L1
20
19
18
17
16
15
14
13
12
D4L0
D3L1
D3L0
D2L1
D2L0
D1L1
D1L0
D0L1
D0L0
DMA0 IPL
DMA1 IPL
DMA2 IPL
DMA3 IPL
DMA4 IPL
DMA5 IPL
11
10
9
8
7
6
5
IDL2
IDL1
IDL0
ICL2
ICL1
ICL0
IBL2
4
IBL1
3
IBL0
2
1
0
IAL2
IAL1
IAL0
IRQA IPL
IRQA mode
IRQB IPL
IRQB mode
IRQC IPL
IRQC mode
IRQD IPL
IRQD mode
Figure 4-2. Interrupt Priority Register-Core (IPRC) (X:$FFFFFF)
23
22
21
20
19
18
17
16
15
14
13
12
Reserved
11
10
9
T0L1
8
7
6
5
T0L0
SCL1
SCL0
S1L1
4
S1L0
3
2
1
0
S0L1
S0L0
HPL1
HPL0
HI08 IPL
ESSI0 IPL
ESSI1 IPL
SCI IPL
TRIPLE TIMER IPL
reserved
Reserved bit; read as zero; write with zero for future compatibility
Figure 4-3. Interrupt Priority Register-Peripherals (IPRP) (X:$FFFFFE)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-13
Core Configuration
The DSP56321 has a four-level interrupt priority structure. Each interrupt has two interrupt
priority level bits (IPL[1–0]) that determine its interrupt priority level. Level 0 is the lowest
priority; Level 3 is the highest-level priority and is non-maskable. Table 4-4 defines the IPL bits.
Table 4-4. Interrupt Priority Level Bits
IPL bits
Interrupts Enabled
Interrupts Masked
Interrupt Priority Level
0
No
—
0
0
1
Yes
0
1
1
0
Yes
0, 1
2
1
1
Yes
0, 1, 2
3
xxL1
xxL0
0
The IPRC also selects the trigger mode of the external interrupts (IRQA–IRQD). If the value of the
IxL2 bit is 0, the interrupt mode is level-triggered. If the value is 1, the interrupt mode is
negative-edge-triggered.
4.4.2 Interrupt Table Memory Map
Each interrupt is allocated two instructions in the interrupt table, resulting in 128 table entries for
interrupt handling. Table 4-5 shows the table entry address for each interrupt source. The
DSP56321 initialization program loads the table entry for each interrupt serviced with two
interrupt servicing instructions. In the DSP56321, only some of the 128 vector addresses are used
for specific interrupt sources. The remaining interrupt vectors are reserved and can be used for
host NMI (IPL = 3) or for host command interrupt (IPL = 2). Unused interrupt vector locations can
be used for program or data storage.
Table 4-5. Interrupt Sources
Interrupt
Starting Address
Interrupt Priority
Level Range
VBA:$00
3
Hardware RESET
VBA:$02
3
Stack error
VBA:$04
3
Illegal instruction
VBA:$06
3
Debug request interrupt
VBA:$08
3
Trap
VBA:$0A
3
Nonmaskable interrupt (NMI)
VBA:$0C
3
Reserved
VBA:$0E
3
Reserved
VBA:$10
0–2
IRQA
VBA:$12
0–2
IRQB
Interrupt Source
DSP56321 Reference Manual, Rev. 1
4-14
Freescale Semiconductor
Configuring Interrupts
Table 4-5. Interrupt Sources (Continued)
Interrupt
Starting Address
Interrupt Priority
Level Range
VBA:$14
0–2
IRQC
VBA:$16
0–2
IRQD
VBA:$18
0–2
DMA channel 0
VBA:$1A
0–2
DMA channel 1
VBA:$1C
0–2
DMA channel 2
VBA:$1E
0–2
DMA channel 3
VBA:$20
0–2
DMA channel 4
VBA:$22
0–2
DMA channel 5
VBA:$24
0–2
TIMER 0 compare
VBA:$26
0–2
TIMER 0 overflow
VBA:$28
0–2
TIMER 1 compare
VBA:$2A
0–2
TIMER 1 overflow
VBA:$2C
0–2
TIMER 2 compare
VBA:$2E
0–2
TIMER 2 overflow
VBA:$30
0–2
ESSI0 receive data
VBA:$32
0–2
ESSI0 receive data with exception status
VBA:$34
0–2
ESSI0 receive last slot
VBA:$36
0–2
ESSI0 transmit data
VBA:$38
0–2
ESSI0 transmit data with exception status
VBA:$3A
0–2
ESSI0 transmit last slot
VBA:$3C
0–2
Reserved
VBA:$3E
0–2
Reserved
VBA:$40
0–2
ESSI1 receive data
VBA:$42
0–2
ESSI1 receive data with exception status
VBA:$44
0–2
ESSI1 receive last slot
VBA:$46
0–2
ESSI1 transmit data
VBA:$48
0–2
ESSI1 transmit data with exception status
VBA:$4A
0–2
ESSI1 transmit last slot
VBA:$4C
0–2
Reserved
VBA:$4E
0–2
Reserved
VBA:$50
0–2
SCI receive data
VBA:$52
0–2
SCI receive data with exception status
VBA:$54
0–2
SCI transmit data
VBA:$56
0–2
SCI idle line
VBA:$58
0–2
SCI timer
VBA:$5A
0–2
Reserved
Interrupt Source
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-15
Core Configuration
Table 4-5. Interrupt Sources (Continued)
Interrupt
Starting Address
Interrupt Priority
Level Range
VBA:$5C
0–2
Reserved
VBA:$5E
0–2
Reserved
VBA:$60
0–2
Host receive data full
VBA:$62
0–2
Host transmit data empty
VBA:$64
0–2
Host command (default)
VBA:$66
0–2
Reserved
VBA:$68
0–2
EFCOP Data Input Buffer Empty
VBA:$6A
0–2
EFCOP Data Output Buffer Full
VBA:$6C
0–2
Reserved
:
:
VBA:$FE
0–2
Interrupt Source
:
Reserved
4.4.3 Processing Interrupt Source Priorities Within an IPL
If more than one interrupt request is pending when an instruction executes, the interrupt source
with the highest IPL is serviced first. When several interrupt requests with the same IPL are
pending, another fixed-priority structure within that IPL determines which interrupt source is
serviced first. Table 4-6 shows this fixed-priority list of interrupt sources within an IPL, from
highest to lowest at each level The interrupt mask bits in the Status Register (I[1–0]) can be
programmed to ignore low priority-level interrupt requests.
Table 4-6. Interrupt Source Priorities Within an IPL
Priority
Interrupt Source
Level 3 (nonmaskable)
Highest
Hardware RESET
Stack error
Illegal instruction
Debug request interrupt
Trap
Lowest
Nonmaskable interrupt
Levels 0, 1, 2 (maskable)
Highest
IRQA (external interrupt)
IRQB (external interrupt)
IRQC (external interrupt)
IRQD (external interrupt)
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4-16
Freescale Semiconductor
Configuring Interrupts
Table 4-6. Interrupt Source Priorities Within an IPL (Continued)
Priority
Interrupt Source
DMA channel 0 interrupt
DMA channel 1 interrupt
DMA channel 2 interrupt
DMA channel 3 interrupt
DMA channel 4 interrupt
DMA channel 5 interrupt
Host command interrupt
Host transmit data empty
Host receive data full
ESSI0 RX data with exception interrupt
ESSI0 RX data interrupt
ESSI0 receive last slot interrupt
ESSI0 TX data with exception interrupt
ESSI0 transmit last slot interrupt
ESSI0 TX data interrupt
ESSI1 RX data with exception interrupt
ESSI1 RX data interrupt
ESSI1 receive last slot interrupt
ESSI1 TX data with exception interrupt
ESSI1 transmit last slot interrupt
ESSI1 TX data interrupt
SCI receive data with exception interrupt
SCI receive data
SCI transmit data
SCI idle line
SCI timer
TIMER0 overflow interrupt
TIMER0 compare interrupt
TIMER1 overflow interrupt
TIMER1 compare interrupt
TIMER2 overflow interrupt
TIMER2 compare interrupt
EFCOP Data Input Buffer Empty
Lowest
EFCOP Data Output Buffer Full
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-17
Core Configuration
4.5 Bus Interface Unit (BIU) Registers
The three Bus Interface Unit (BIU) registers configure the external memory expansion port (Port
A). They include the following:
„
„
Bus Control Register (BCR)
Address Attribute Registers (AAR[3–0])
To use Port A correctly, configure these registers as part of the bootstrap process. The following
subsections describe these registers.
4.5.1 Bus Control Register
The Bus Control Register (BCR), depicted in Figure 4-5, is a read/write register that controls the
external bus activity and Bus Interface Unit (BIU) operation. All BCR bits except bit 21, BBS,
are read/write bits.
23
22
BRH
21
20
19
18
17
16
15
14
13
12
BBS
BDFW4
BDFW3
BDFW2
BDFW1
BDFW0
BA3W2
BA3W1
BA3W0
BA2W2
11
10
9
8
7
6
5
4
3
2
1
0
BA2W1
BA2W0
BA1W4
BA1W3
BA1W2
BA1W1
BA1W0
BA0W4
BA0W3
BA0W2
BA0W1
BA0W0
Reserved bit. Read as zero; write to zero for future compatibility
Table 4-7. Bus Control Register (BCR) Bit Definitions
Bit
Number
Bit Name
Reset Value
Description
23
BRH
0
Bus Request Hold
Asserts the BR signal, even if no external access is needed. When BRH is set, the
BR signal is always asserted. If BRH is cleared, the BR is asserted only if an external
access is attempted or pending.
0
Reserved. Write to 0 for future compatibility.
Bus State
This read-only bit is set when the DSP is the bus master and is cleared otherwise.
22
21
BBS
0
20–16
BDFW[4–0]
11111
(31 wait
states)
Bus Default Area Wait State Control
Defines the number of wait states (one through 31) inserted into each external
access to an area that is not defined by any of the AAR registers. The access type for
this area is SRAM only. These bits should not be programmed as zero since SRAM
memory access requires at least one wait state.
When three through seven wait states are selected, one additional wait state is
inserted at the end of the access. When selecting eight or more wait states, two
additional wait states are inserted at the end of the access. These trailing wait states
increase the data hold time and the memory release time and do not increase the
memory access time.
DSP56321 Reference Manual, Rev. 1
4-18
Freescale Semiconductor
Bus Interface Unit (BIU) Registers
Table 4-7. Bus Control Register (BCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset Value
15–13
BA3W[2–0]
111
(7 wait
states)
Description
Bus Area 3 Wait State Control
Defines the number of wait states (1–7) inserted in each external SRAM access to
Area 3. Area 3 is the area defined by AAR3.
Note:
Do not program the value of these bits as zero since SRAM memory access
requires at least one wait state.
When three through seven wait states are selected, one additional wait state is
inserted at the end of the access. This trailing wait state increases the data hold time
and the memory release time and does not increase the memory access time.
12–10
BA2W[2–0]
111
(7 wait
states)
Bus Area 2 Wait State Control
Defines the number of wait states (1–7) inserted into each external SRAM access to
Area 2. Area 2 is the area defined by AAR2.
Note:
Do not program the value of these bits as zero, since SRAM memory
access requires at least one wait state.
When three through seven wait states are selected, one additional wait state is
inserted at the end of the access. This trailing wait state increases the data hold time
and the memory release time and does not increase the memory access time.
9–5
BA1W[4–0]
11111
(31 wait
states)
Bus Area 1 Wait State Control
Defines the number of wait states (1–31) inserted into each external SRAM access to
Area 1. Area 1 is the area defined by AAR1.
Note:
Do not program the value of these bits as zero, since SRAM memory
access requires at least one wait state.
When three through seven wait states are selected, one additional wait state is
inserted at the end of the access. When selecting eight or more wait states, two
additional wait states are inserted at the end of the access. These trailing wait states
increase the data hold time and the memory release time and do not increase the
memory access time.
4–0
BA0W[4–0]
11111
(31 wait
states)
Bus Area 0 Wait State Control
Defines the number of wait states (1–31) inserted in each external SRAM access to
Area 0. Area 0 is the area defined by AAR0.
Note:
Do not program the value of these bits as zero, since SRAM memory
access requires at least one wait state.
When selecting three through seven wait states, one additional wait state is inserted
at the end of the access. When selecting eight or more wait states, two additional
wait states are inserted at the end of the access. These trailing wait states increase
the data hold time and the memory release time and do not increase the memory
access time.
4.5.2 Address Attribute Registers (AAR[0–3])
The Address Attribute Registers (AAR[0–3]) are read/write registers that control the activity of
the AA[0–3] pins. The associated AAn pin is asserted if the address defined by the BAC bits in the
associated AAR matches the exact number of external address bits defined by the BNC bits, and
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-19
Core Configuration
the external address space (X data, Y data, or program) is enabled by the AAR. Figure 4-6 shows
an AAR register; Table 4-8 lists the bit definitions.
Note:
The DSP56321 does not support address multiplexing.
23
22
21
20
19
18
17
16
15
14
13
12
BAC11
BAC10
BAC9
BAC8
BAC7
BAC6
BAC5
BAC4
BAC3
BAC2
BAC1
BAC0
11
10
9
8
7
6
5
4
3
2
1
0
BNC3
BNC2
BNC1
BNC0
BPAC
BYEN
BXEN
BPEN
BAAP
BAT1
BAT0
Reserved bit. Read as zero; write to zero for future compatibility
Figure 4-4. Address Attribute Registers (AAR[0–3]) (X:$FFFFF9–$FFFFF6)
Table 4-8. Address Attribute Registers (AAR[0–3]) Bit Definitions
Bit
Number
Bit Name
Reset
Value
23–12
BAC[11–0]
0
Bus Address to Compare
Read/write control bits that define the upper 12 bits of the 24-bit address with which to
compare the external address to determine whether to assert the corresponding AA signal.
This is also true of 16-bit compatibility mode. The BNC[3–0] bits define the number of address
bits to compare.
11–8
BNC[3–0]
0
Bus Number of Address Bits to Compare
Specify the number of bits (from the BAC bits) that are compared to the external address. The
BAC bits are always compared with the Most Significant Portion of the external address (for
example, if BNC[3–0] = 0011, then the BAC[11–9] bits are compared to the 3 MSBs of the
external address). If no bits are specified (that is, BNC[3–0] = 0000), the AA signal is
activated for the entire 16 M-word space identified by the space enable bits (BPEN, BXEN,
BYEN), but only when the address is external to the internal memory map. The combinations
BNC[3–0] = 1111, 1110, 1101 are reserved.
7
BPAC
0
Bus Packing Enable
Enables/disables the internal packing/unpacking logic. When BPAC is set, packing is
enabled. In this mode each DMA external access initiates three external accesses to an 8-bit
wide external memory (the addresses for these accesses are DAB, then DAB + 1 and then
DAB + 2). Packing to a 24-bit word (or unpacking from a 24-bit word to three 8-bit words) is
done automatically by the expansion port control hardware. The external memory should
reside in the eight Least Significant Bits (LSBs) of the external data bus, and the packing (or
unpacking for external write accesses) occurs in “Little Endian” order (that is, the low byte is
stored in the lowest of the three memory locations and is transferred first; the middle byte is
stored/transferred next; and the high byte is stored/transferred last). When this bit is cleared,
the expansion port control logic assumes a 24-bit wide external memory.
Description
Notes: 1.
2.
3.
4.
BPAC is used only for DMA accesses and not core accesses.
To ensure sequential external accesses, the DMA address should advance
three steps at a time in two-dimensional mode with a row length of one and an
offset size of three. For details, refer to Freescale application note, APR23/D,
Using the DSP56300 Direct Memory Access Controller.
To prevent improper operation, DMA address + 1 and DMA
address + 2 should not cross the AAR bank borders.
Arbitration is not allowed during the packing access (that is, the three accesses
are treated as one access with respect to arbitration, and the bus mastership is
not released during these accesses).
DSP56321 Reference Manual, Rev. 1
4-20
Freescale Semiconductor
DMA Control Registers 5–0 (DCR[5–0])
Table 4-8. Address Attribute Registers (AAR[0–3]) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
6
Description
0
Reserved. Write to 0 for future compatibility.
5
BYEN
0
Bus Y Data Memory Enable
A read/write control bit that enables/disables the AA pin and logic during external Y data
space accesses. When set, BYEN enables the comparison of the external address to the
BAC bits during external Y data space accesses. If BYEN is cleared, no address comparison
is performed.
4
BXEN
0
Bus X Data Memory Enable
A read/write control bit that enables/disables the AA pin and logic during external X data
space accesses. When set, BXEN enables the comparison of the external address to the
BAC bits during external X data space accesses. If BXEN is cleared, no address comparison
is performed.
3
BPEN
0
Bus Program Memory Enable
A read/write control bit that enables/disables the AA pin and logic during external program
space accesses. When set, BPEN enables the comparison of the external address to the
BAC bits during external program space accesses. If BPEN is cleared, no address
comparison is performed.
2
BAAP
0
Bus Address Attribute Polarity
A read/write Bus Address Attribute Polarity (BAAP) control bit that defines whether the AA
signal is active low or active high. When BAAP is cleared, the AA signal is active low (useful
for enabling memory modules). If BAAP is set, the appropriate AA signal is active high (useful
as an additional address bit).
1–0
BAT[1–0]
0
Bus Access Type
Read/write bits that define the type of external memory (SRAM) to access for the area defined
by the BAC[11–0],BYEN, BXEN, and BPEN bits. The encoding of BAT[1–0] is:
• 00 = Reserved
• 01 = SRAM access
• 10 = Reserved
• 11 = Reserved
When the external access type is defined as a SRAM access (BAT[1–0] = 01), AA acts as an
Address Attribute signal. External accesses to the default area always execute as if BAT[1–0]
= 01 (that is, SRAM access). If Port A is used for external accesses, the BAT bits in the
AAR3–0 registers must be initialized to the SRAM access type (that is, BAT = 01). To ensure
proper operation of Port A, this initialization must occur even for an AAR register that is not
used during any Port A access. At reset, the BAT bits are initialized to 00.
4.6 DMA Control Registers 5–0 (DCR[5–0])
The DMA Control Registers (DCR[5–0]) are read/write registers that control the DMA operation
for each of their respective channels. All DCR bits are cleared during processor reset.
23
22
21
20
19
18
17
16
15
14
13
12
DE
DIE
DTM2
DTM1
DTM0
DPR1
DPR0
DCON
DRS4
DRS3
DRS2
DRS1
11
10
9
8
7
6
5
4
3
2
1
0
DRS0
D3D
DAM5
DAM4
DAM3
DAM2
DAM1
DAM0
DDS1
DDS0
DSS1
DSS0
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-21
Core Configuration
Table 4-9. DMA Control Register (DCR) Bit Definitions
Bit
Number
Bit Name
Reset
Value
23
DE
0
DMA Channel Enable
Enables the channel operation. Setting DE either triggers a single block DMA transfer or
enables a single-block, single-line, or single-word DMA transfer in the transfer modes that
use a requesting device as a trigger. DE is cleared by the end of DMA transfer in some of
the transfer modes defined by the DTM bits. If software clears DE during a DMA operation,
the channel operation stops only after the current DMA transfer completes (that is, the
current word is stored into the destination).
22
DIE
0
DMA Interrupt Enable
Generates a DMA interrupt at the end of a DMA block transfer after the counter is loaded
with its preloaded value. A DMA interrupt is also generated when software explicitly clears
DE during a DMA operation. Once asserted, a DMA interrupt request can be cleared only
by the service of a DMA interrupt routine. To ensure that a new interrupt request is not
generated, clear DIE while the DMA interrupt is serviced and before a new DMA request is
generated at the end of a DMA block transfer—that is, at the beginning of the DMA channel
interrupt service routine. When DIE is cleared, the DMA interrupt is disabled.
Description
DSP56321 Reference Manual, Rev. 1
4-22
Freescale Semiconductor
DMA Control Registers 5–0 (DCR[5–0])
Table 4-9. DMA Control Register (DCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
21–19
DTM[2–0]
0
Note:
Description
DMA Transfer Mode
Specify the operating modes of the DMA channel, as follows:
DTM[2–0]
Trigger
DE
Cleared
After
000
request
Yes
Block Transfer—DE enabled and DMA request
initiated. The transfer is complete when the counter
decrements to zero and the DMA controller reloads the
counter with the original value.
001
request
Yes
Word Transfer—A word-by-word block transfer (length
set by the counter) that is DE enabled. The transfer is
complete when the counter decrements to zero and the
DMA controller reloads the counter with the original
value.
010
request
Yes
Line Transfer—A line by line block transfer (length set
by the counter) that is DE enabled. The transfer is
complete when the counter decrements to zero and the
DMA controller reloads the counter with the original
value.
011
DE
Yes
Block Transfer—The DE-initiated transfer is complete
when the counter decrements to zero and the DMA
controller reloads the counter with the original value.
100
request
No
Block Transfer—The transfer is enabled by DE and
initiated by the first DMA request. The transfer is
completed when the counter decrements to zero and
reloads itself with the original value. The DE bit is not
cleared at the end of the block, so the DMA channel
waits for a new request. The DMA End-of-Block
Transfer Interrupt cannot be used in this mode.
101
request
No
Word Transfer—The transfer is enabled by DE and
initiated by every DMA request. When the counter
decrements to zero, it is reloaded with its original
value. The DE bit is not automatically cleared, so the
DMA channel waits for a new request. The DMA
End-of-Block-Transfer Interrupt cannot be used in this
mode.
Transfer Mode
110
Reserved
111
Reserved
When DTM[2–0] = 001 or 101, some peripherals can generate a second DMA request while the DMA controller is still
processing the first request (see the description of the DRS bits).
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-23
Core Configuration
Table 4-9. DMA Control Register (DCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
18–17
DPR[1–0]
0
Description
DMA Channel Priority
Define the DMA channel priority relative to the other DMA channels and to the core priority
if an external bus access is required. For pending DMA transfers, the DMA controller
compares channel priority levels to determine which channel can activate the next word
transfer. This decision is required because all channels use common resources, such as
the DMA address generation logic, buses, and so forth.
DPR[1–0]
Channel Priority
00
Priority level 0 (lowest)
01
Priority level 1
10
Priority level 2
11
Priority level 3 (highest)
• If all or some channels have the same priority, then channels are activated in a
round-robin fashion—that is, channel 0 is activated to transfer one word, followed by
channel 1, then channel 2, and so on.
• If channels have different priorities, the highest priority channel executes DMA transfers
and continues for its pending DMA transfers.
• If a lower-priority channel is executing DMA transfers when a higher priority channel
receives a transfer request, the lower-priority channel finishes the current word transfer
and arbitration starts again.
• If some channels with the same priority are active in a round-robin fashion and a new
higher-priority channel receives a transfer request, the higher-priority channel is granted
transfer access after the current word transfer is complete. After the higher-priority
channel transfers are complete, the round-robin transfers continue. The order of
transfers in the round-robin mode may change, but the algorithm remains the same.
• The DPR bits also determine the DMA priority relative to the core priority for external bus
access. Arbitration uses the current active DMA priority, the core priority defined by the
SR bits CP[1–0], and the core-DMA priority defined by the OMR bits CDP[1–0]. Priority
of core accesses to external memory is as follows:
DSP56321 Reference Manual, Rev. 1
4-24
Freescale Semiconductor
DMA Control Registers 5–0 (DCR[5–0])
Table 4-9. DMA Control Register (DCR) Bit Definitions (Continued)
Bit
Number
18–17
cont.
Bit Name
Reset
Value
DPR[1–0]
Description
OMR - CDP[1–0]
CP[1–0]
Core Priority
00
00
0 (lowest)
00
01
1
00
10
2
00
11
3 (highest)
01
xx
DMA accesses have higher priority than
core accesses
10
xx
DMA accesses have the same priority as
core accesses
11
xx
DMA accesses have lower priority than core
accesses
• If DMA priority > core priority (for example, if CDP = 01, or CDP = 00 and
DPR > CP), the DMA performs the external bus access first and the core waits for the
DMA channel to complete the current transfer.
• If DMA priority = core priority (for example, if CDP = 10, or CDP = 00 and
DPR = CP), the core performs all its external accesses first and then the DMA channel
performs its access.
• If DMA priority < core priority (for example, if CDP=11, or CDP = 00 and
DPR < CP), the core performs its external accesses and the DMA waits for a free slot in
which the core does not require the external bus.
• In Dynamic Priority mode (CDP = 00), the DMA channel can be halted before executing
both the source and destination accesses if the core has higher priority. If another
higher-priority DMA channel requests access, the halted channel finishes its previous
access with a new higher priority before the new requesting DMA channel is serviced.
16
DCON
0
DMA Continuous Mode Enable
Enables/disables DMA Continuous mode. When DCON is set, the channel enters the
Continuous Transfer mode and cannot be interrupted during a transfer by any other DMA
channel of equal priority. DMA transfers in the continuous mode of operation can be
interrupted if a DMA channel of higher priority is enabled after the continuous mode
transfer starts. If the priority of the DMA transfer in continuous mode (that is, DCON = 1) is
higher than the core priority (CDP = 01, or CDP = 00 and DPR > CP), and if the DMA
requires an external access, the DMA gets the external bus and the core is not able to use
the external bus in the next cycle after the DMA access even if the DMA does not need the
bus in this cycle. When DCON is cleared, the priority algorithm operates as for the DPR
bits.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-25
Core Configuration
Table 4-9. DMA Control Register (DCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
15–11
DRS[4–0]
0
Description
DMA Request Source
Encodes the source of DMA requests that trigger the DMA transfers. The DMA request
sources may be external devices requesting service through the IRQA, IRQB, IRQC and
IRQD pins, triggering by transfers done from a DMA channel, or transfers from the internal
peripherals. All the request sources behave as edge-triggered synchronous inputs.
DRS[4–0]
Requesting Device
00000
External (IRQA pin)
00001
External (IRQB pin)
00010
External (IRQC pin)
00011
External (IRQD pin)
00100
Transfer done from channel 0
00101
Transfer done from channel 1
00110
Transfer done from channel 2
00111
Transfer done from channel 3
01000
Transfer done from channel 4
01001
Transfer done from channel 5
01010
ESSI0 receive data (RDF0 = 1)
01011
ESSI0 transmit data (TDE0 = 1)
01100
ESSI1 receive data (RDF1 = 1)
01101
ESSI1 transmit data (TDE1 = 1)
01110
SCI receive data (RDRF = 1)
01111
SCI transmit data (TDRE = 1)
10000
Timer0 (TCF0 = 1)
10001
Timer1 (TCF1 = 1)
10010
Timer2 (TCF2 = 1)
10011
Host receive data full (HRDF = 1)
10100
Host transmit data empty (HTDE = 1)
10101
EFCOP input buffer empty (FDIBE=1)
10110
EFCOP output buffer full (FDOBF=1)
10111–11111
Reserved
Peripheral requests 18–21 (DRS[4–0] = 111xx) can serve as fast request sources. Unlike a
regular peripheral request in which the peripheral can not generate a second request until
the first one is served, a fast peripheral has a full duplex handshake to the DMA, enabling a
maximum throughput of a trigger every two clock cycles. This mode is functional only in the
Word Transfer mode (that is, DTM = 001 or 101). In the Fast Request mode, the DMA sets
an enable line to the peripheral. If required, the peripheral can send the DMA a one cycle
triggering pulse. This pulse resets the enable line. If the DMA decides by the priority
algorithm that this trigger will be served in the next cycle, the enable line is set again, even
before the corresponding register in the peripheral is accessed.
DSP56321 Reference Manual, Rev. 1
4-26
Freescale Semiconductor
Device Identification Register (IDR)
Table 4-9. DMA Control Register (DCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
10
D3D
0
Three-Dimensional Mode
Indicates whether a DMA channel is currently using three-dimensional (D3D = 1) or
non-three-dimensional (D3D = 0) addressing modes. The addressing modes are specified
by the DAM bits.
9–4
DAM[5–0]
0
DMA Address Mode
Defines the address generation mode for the DMA transfer. These bits are encoded in two
different ways according to the D3D bit.
3–2
DDS[1–0]
0
DMA Destination Space
Specify the memory space referenced as a destination by the DMA.
Note: In Cache mode, a DMA to Program memory space has some limitations (as
described in the instruction cache chapter of the DSP56300 Family Manual and in
the chapter on operating modes).
1–0
Note:
DSS[1–0]
0
Description
DDS1
DDS0
DMA Destination Memory Space
0
0
X Memory Space
0
1
Y Memory Space
1
0
P Memory Space
1
1
Reserved
DMA Source Space
Specify the memory space referenced as a source by the DMA. In Cache mode, a DMA to
Program memory space has some limitations (as described in the instruction cache
chapter of the DSP56300 Family Manual in and the chapter on operating modes).
DSS1
DSS0
DMA Source Memory Space
0
0
X Memory Space
0
1
Y Memory Space
1
0
P Memory Space
1
1
Reserved
The lowest 12 K of X data RAM and 12 K of Y data RAM are shared memory that can
be accessed by the core and the EFCOP but not by the DMA controller.
4.7 Device Identification Register (IDR)
The IDR is a read-only factory-programmed register that identifies DSP56300 family members.
It specifies the derivative number and revision number of the device. This information is used in
testing or by software. Figure 4-8 shows the contents of the IDR. Revision numbers are assigned
as follows: $0 is revision 0, $1 is revision A, and so on.
.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
4-27
Core Configuration
23
16
15
12
11
0
Reserved
Revision Number
Derivative Number
$00
$0
$321
Figure 4-5. Identification Register Configuration (Revision A)
4.8 JTAG Identification (ID) Register
The JTAG ID register is a 32-bit read-only factory-programmed register that distinguishes the
component on a board according to the IEEE 1149.1 standard. Figure 4-9 shows the JTAG ID
register configuration. Version information corresponds to the revision number ($0 for revision 0,
$1 for revision A, etc.).
I)
31
28
27
22
21
12
11
1
0
Version Information
Design Center
Number
Sequence
Number
Manufacturer
Identity
1
0000
000110
0000010101
00000001110
1
Figure 4-6. JTAG Identification Register Configuration (Revision 0)
4.9 JTAG Boundary Scan Register (BSR)
The BSR in the DSP56321 JTAG implementation contains bits for all device signals, clock pins,
and their associated control signals. All DSP56321 bidirectional pins have a corresponding
register bit in the BSR for pin data and are controlled by an associated control bit in the BSR. For
details on the BSR, consult the DSP56300 Family Manual.
DSP56321 Reference Manual, Rev. 1
4-28
Freescale Semiconductor
Clock Configuration
5
The DSP56321 features a clock generator (CLKGEN) module that allows the processor to
operate at a high internal clock frequency derived from a low-frequency clock input, a feature
that offers two immediate benefits. The lower frequency clock input reduces the overall
electromagnetic interference generated by a system. Oscillating at different frequencies reduces
costs by eliminating the need to add oscillators to a system.
Note:
The DSP56321 uses a new CLKGEN module with an integrated Digital Phase-Lock
Loop (DPLL) circuit. This CLKGEN module is different from the PLL and clock
generator provided by the standard DSP56300 core.
5.1 Overview
The DSP56321 clock generator has a digital PLL (DPLL) that performs
„
„
„
Clock Input Frequency Division
Frequency multiplication
Skew reduction
In addition, the CLKGEN has the following functionality:
„
„
„
Low power division.
Internal clock generation
Source clock switching
This chapter describes the implementation of the CLKGEN module in the DSP56321.
5.2 Clock Generation Scheme
Figure 5-1 shows the principal clock generation scheme in the DSP56321.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
5-1
Clock Configuration
I/O Cells
CLKGEN
Internal
Clocks
Output Stage
EXTAL
I/O
Logic
CRCKD
DPDCK
DPLL
Low-Power
Divider DVDCK
XTAL
DBLCK
Ext.
Clock
GCLK
Global
Clocks
Generator
(divide-by-2)
GCLKD
GCLKW
GCLKWD
DSP56321
Figure 5-1. Clock Generation Diagram
The clock source can be either an external source applied to EXTAL or a crystal and associated
components connected between EXTAL and XTAL. Refer to the DSP56321 Technical Data
sheet for detailed information about circuit requirements.
5.3 Clock Acronym List
Table 5-1 lists acronyms used in this chapter to describe the CLKGEN module.
Table 5-1. Acronyms
Acronym
Description
BRM
Binary Rate Modulator
CLKGEN
Clock Generator module
CRCKD
CLKGEN Reference Clock to the DPLL
DAC
Digital-to-Analog Converter
DBLCK
Double Clock input to the Global Clock Generator
DF
Post-Division Factor value programmed in the DPLL Control Register (PCTL). See Table 5-2 for
details.
DPDCK
DPLL output Clock to the Low Power Divider
DPFD
Digital Phase-Frequency Detector
DPLL
Digital Phase-Lock Loop
DSCR
DPLL Static Control Register. See Table 5-3 for details.
DVDCK
Divided DPLL Clock output
FOL
Frequency-Only Lock mode
DSP56321 Reference Manual, Rev. 1
5-2
Freescale Semiconductor
CLKGEN External Pins
Table 5-1. Acronyms (Continued)
Acronym
Description
FPL
Frequency and Phase Lock mode
GCLK, GCLKD,
GCLKW, GCLKWD
Global System Clocks used by the DSP56321 internally
MF
MFD
MFI
MFN
DPLL Multiplication Factor is computed from three elements according to the following formula:
MF = MFI + (MFN/MFD)
MFI, MFN, and MFD are programmed as fields in the DSCR. See Table 5-3 for details.
Note: MF is limited to the range 5–15. If MFI = 15, then MFN must be programmed as 0.
PCTL
DPLL Control Register. See Table 5-2 for details.
PDF
DPLL Pre-Division Factor programmed in the DSCR. See Table 5-3 for details.
VCO
Voltage-Controlled Oscillator
5.4 CLKGEN External Pins
All external connections link to the CLKGEN module through on-chip I/O cells, as shown in
Figure 5-1. The following pins are dedicated to the CLKGEN operation:
„
„
„
EXTAL.
External clock/crystal input used to interface an external clock or to support the
on-chip oscillator with an external crystal circuit.
PINIT. During assertion of hardware reset, the value of the PINIT input pin is written into
the PCTL DPLL Enable (PEN) bit. After hardware reset is deasserted, the DPLL ignores
the PINIT pin, and it can have a different function in the device.
XTAL. Crystal output connection to support the on-chip oscillator.
5.5 DPLL
This section describes the major DPLL functions. The DPLL functional block diagram is shown
in Figure 5-1.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
5-3
Clock Configuration
CRCKD
Predivider
(1–16)
Digital
PhaseFrequency
Detector
PWM
Σ
Digital
Control
5
DA
Analog
Smoothing
Filter
VCO
Divideby-2
DPDCK
Divided
Reference
Frequency
Phase
Adjusting
Block
SDM
SelfCalibration
Block
Lock
Control
Equivalent Delay
BRM
(5–15)
Chip Clock Divideby-2
Figure 5-2. DPLL Block Diagram
5.5.1 DPLL Description
The Predivider divides the CLKGEN Reference Frequency (CRCKD) using a division factor
with an integer value in the range 1–16. The value is programmed by the PDF bit field in the
DSCR.
Note:
The Predivider introduces a delay independent of the Pre-Division Factor.
The divided reference clock is fed to the Digital Phase-Frequency Detector (DPFD). The DPFD
receives a second input from the Binary Rate Modulator (BRM) output. The BRM receives the
Chip Clock, which is the double clock DPDCK divided by 2. The BRM division factor is MF,
which is equal to MFI + (MFD/MFN). The values for each of these elements (that is, MFI, MFD,
and MFN) are programmed in their respective bit fields in the DSCR.
The DPFD is implemented as a 5-bit asynchronous up/down counter. The counter content is
incremented by 1 at a positive edge of the reference clock and decremented by 1 at a positive
edge of the divided double clock. Thus, the counter produces a multilevel PWM signal used for
control of a frequency of the voltage controlled oscillator (VCO). Digital VCO control is
performed by a 5-bit digital-to-analog converter (DAC). A first order lowpass RC filter smooths
the multilevel PWM signal from the DAC output. A frequency of the VCO controlled with the
LPF output is proportional to a mean level of the PWM signal. The VCO frequency is two times
DSP56321 Reference Manual, Rev. 1
5-4
Freescale Semiconductor
Clock Generator Output Stage
higher than DPDCK. The VCO output is sent through a Divide-by-2 circuit to generate the
DPDCK output.
During lock-in time, the divided double clock frequency (that is, the Chip Clock) differs from the
divided reference frequency. If the divided reference frequency is higher than the chip clock
frequency, the counter content increases and raises the VCO frequency. If the feedback clock
(that is, the chip clock) frequency is higher than the divided reference frequency, the counter
content decreases and lowers the VCO frequency. The closed feedback loop via the BRM forces
the system to go to a steady state, in which both DPFD input signals have equal frequencies (that
is, the multilevel PWM signal on the DPFD output has a constant duty cycle). The PWM duty
cycle determines the mean DAC output, which in turn tunes the VCO to the proper frequency.
The duty cycle may change slowly with variations in a VCO characteristic, such as that caused by
changes in temperature, for example.
If the DPLL operates in the FOL mode, the Phase Adjusting Block is disabled and only the DPFD
controls the VCO frequency. In this mode, the divided VCO frequency is exactly equal to the
divided reference frequency at short time intervals, but there is an unrestricted phase offset
between reference and output clocks. This phase offset can drift slowly with temperature and
supply voltage changes.
In the FPL mode, the Phase Adjusting Block produced an additional control signal that
minimizes the skew between reference and output clocks. Therefore, the skew is constant
independent of temperature and supply voltage variations.
The BRM consists of a controlled divider with a division factor from 5 to 16 and a sigma delta
modulator. The first or second order of the modulator is selected by BRMO bit. The sigma delta
modulator generates pulse series with a mean value of MFN/MFD. If the BRM has the first order,
its output may be 0 or 1. The second-order BRM output may be –1, 0, 1, 2. The total mean
division factor is MF = MFI + (MFN/MFD). Thus, a current period of the BRM output clock can
be variable for a fractional MF but an average clock frequency is equal to DPDCK / (2 × MF).
The DPLL also includes a Self-Calibration Block. This block regulates the DAC gain at start-up
in order to ensure that the total loop gain is proportional to the reference frequency and
independent of the multiplication factor and process variations.
The Lock Control module contains a set of timers intended to generate all necessary control
signals during lock-in time. This module also controls the lock flag.
5.6 Clock Generator Output Stage
The clock generator output stage uses the EXTAL input (PEN = 0 and the DPLL is disabled) or
the DPLL output (PEN = 1 and the DPLL is enabled and locked) to generate the core clock.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
5-5
Clock Configuration
5.6.1 EXTAL as Clock Source
If the signal comes from EXTAL directly, it feeds directly to the Global Clock Generator. For
EXTAL (PEN = 0, PLL disabled) use the following formula:
F
Fextal
EXTAL
-------------2
5.6.2 DPLL as Clock Source
If the signal comes from the DPLL it passes through the Low Power Divider before going to the
Global Clock Generator. The Low-Power Divider (LPD) divides the output frequency of the
DPLL by any power of 2 from 20 to 27. The Division Factor (DF) of the LPD can be modified by
changing the value of the PLL Control Register (PCTL) Division Factor bits DF[2–0]. Since the
LPD is not in the closed loop of the DPLL, changes in the DF do not cause a loss of lock
condition. The result is a significant power savings when the LPD operates in low-power
consumption modes as the device is not involved in intensive calculations. When the device is
required to exit a low-power mode, it can do so immediately with no time needed for clock
recovery or PLL lock.
For the DPLL clock source (PEN = 1, PLL enabled), the operating frequency (FCHIP) can be
calculated as:
-------------⎞
× ⎛⎝ MFI + MFN
MFD⎠
----------------------------------------------PDF × DF
F EXTAL
F CHIP =
5.6.3 Global Clock Generator
The Global Clock Generator is a divide-by-2 circuit that generates the two-phase chip clock
signals to the core and the device peripherals.
5.7 CLKGEN Programming Model
The CLKGEN control registers are two X-I/O mapped 24-bit read/write registers to direct the
operation of the on-chip DPLL. The following subsections define these registers.
5.7.1 DPLL Clock Control (PCTL) Register
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
DF2
DF1
DF0
PEN
XTLD
PSTP
Reserved, write as zeros to maintain future compatibility.
DSP56321 Reference Manual, Rev. 1
5-6
Freescale Semiconductor
CLKGEN Programming Model
Table 5-2. DPLL Clock Control Register (PCTL)
Bit
Number
Bit Name
Reset
Value
23–7
reserved
0
6–4
DF[2–0]
011
Description
These bits are reserved for future purposes.
Division Factor
Defines the low-power divider specified as a power of two in the range from 20 to 27.
Changing the value of the DF[2–0] bits does not cause a loss of lock condition.
DF[2–0]
DF Value
000
20
001
21
010
22
011
23
100
24
101
25
110
26
111
27
3
PEN
PINIT
DPLL Enable
When PEN is set, the DPLL is enabled; when the DPLL locks, the internal clocks are
derived from the DPLL output. When PEN is cleared, the internal clocks are derived
directly from the EXTAL signal. Disabling the DPLL minimizes power consumption. The
PEN bit may be set or cleared by software any time during the device operation. During
hardware reset, this bit is set or cleared based on the value of the DPLL PINIT input.
2
XTLD
0
XTAL Disable
Controls the XTAL output from the crystal oscillator on-chip driver. When XTLD is
cleared, the XTAL output pin is active, permitting normal operation of the crystal
oscillator. When XTLD is set, the XTAL output pin is pulled high, disabling the on-chip
oscillator driver. If the on-chip crystal oscillator driver is not used (that is, EXTAL is driven
from an external clock source), set XTLD (disabling XTAL) to minimize RFI noise and
power dissipation.
1
PSTP
0
DPLL Stop State Control
Determines DPLL and on-chip crystal oscillator behavior during the Stop processing
state. When PSTP is set, the DPLL and the on-chip crystal oscillator remain operating
when the chip is in the Stop state. When PSTP is cleared and the device enters the Stop
state, the DPLL and the on-chip crystal oscillator are disabled to reduce power
consumption; however, this results in longer recovery time upon exit from the Stop state.
To enable rapid recovery when exiting the Stop state (at the cost of higher power
consumption during the Stop state), PSTP should be set.
Note: PSTP and PEN are related. When PSTP is set and PEN is cleared, the on-chip
crystal oscillator remains operating in the Stop state, but the DPLL is disabled.
This power saving feature enables rapid recovery from the Stop state when you
operate the device with an on-chip oscillator and with the DPLL disabled.
Operation during Stop State
PSTP
PEN
DPLL
Oscillator
(XTLD=0)
Recovery
Time from
Stop State
Power
Consumption
during Stop
State
0
X
Disabled
Disabled
Long
Minimal
1
0
Disabled
Enabled
Short
Low
1
1
Enabled
Enabled
Short
High
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
5-7
Clock Configuration
Table 5-2. DPLL Clock Control Register (PCTL) (Continued)
Bit
Number
Bit Name
Reset
Value
0
reserved
0
Description
This bit is reserved.
Note:
Although this bit is cleared after reset, it enables the output of a reserved signal
used for Freescale development purposes. To prevent possible noise
generation, Freescale recommends writing a 1 to this bit after reset to disable
the reserved signal output.
5.7.2 DPLL Static Control Register (DSCR)
23
22
21
20
19
18
17
16
15
14
13
12
BRMO
PLM
PDF3
PDF2
PDF1
PDF0
MFD6
MFD5
MFD4
MFD3
MFD2
MFD1
11
10
9
8
7
6
5
4
3
2
1
0
MFD0
MFN6
MFN5
MFN4
MFN3
MFN2
MFN1
MFN0
MFI3
MFI2
MFI1
MFI0
Table 5-3. DPLL Static Control Register (DSCR) Bit Definitions
Bit
Number
Bit name
Reset
Value
23
BRMO
1
Description
Binary Rate Modulation Order
The value of BRMO determines the output order used by the Binary Rate Modulator
(BRM). If BRMO is cleared (0), the BRM uses a first order output. If BRMO is set (1), the
BRM uses a second order output. If the DPLL Multiplication Factor Denominator (MFD)
is < 8, then use a first order output (that is, BRMO = 0). If MFD > 8, use a second order
output (that is, BRMO = 1). If the DPLL Multiplication Factor Numerator (MFN) is 0, this
bit is ignored.
Note:
22
PLM
1
21–18
PDF[3–0]
0000
The DPLL will not operate correctly if this bit is not configured appropriately.
Phase Lock Mode
When this bit is cleared (0), the DPLL operates in Frequency Only Lock (FOL) mode.
When this bit is set (1), the DPLL operates in Frequency and Phase Lock (FPL) mode.
FPL mode can be used for both an integer and fractional multiplication factor, but phase
skew reduction is accomplished only for the integer MF.
Pre-Division Factor (PDF)
Defines the DPLL PDF value in the range 1–16.
Note:
The value of PDF bits written into DSCR must be the factor value minus 1.
PDF[3–0]
PDF Value
0000
1
0001
2
0010
3
.
.
.
.
.
.
1111
16
DSP56321 Reference Manual, Rev. 1
5-8
Freescale Semiconductor
CLKGEN Programming Model
Table 5-3. DPLL Static Control Register (DSCR) Bit Definitions (Continued)
Bit
Number
Bit name
Reset
Value
17–11
MFD[6–0]
0000000
Description
Multiplication Factor Denominator (MFD)
Defines the denominator of the fractional part of the Multiplication Factor (MF). The MFD
can be any integer from 1 to 128.
Note:
The value of MFD bits written into DSCR must be the denominator value minus
1. The MFD value must be higher than the MFN value
MFD[6–0]
MFD Value
$00
1
$01
2
$02
3
.
.
.
10–4
MFN[6–0]
0000000
$7E
127
$7F
128
Multiplication Factor Numerator (MFN)
Defines the numerator of the fractional part of the MF. The MFN can be any integer from
0 to 127.
Note:
The total MF is limited to a maximum of 15. Therefore, if the MFI is
programmed as 15 (that is, MFI[3–0] = 1111), MFN must equal 0.
MFN[6–0]
MFN Value
$00
0
$01
1
$02
2
.
.
.
$7E
126
$7F
127
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
5-9
Clock Configuration
Table 5-3. DPLL Static Control Register (DSCR) Bit Definitions (Continued)
Bit
Number
Bit name
Reset
Value
3–0
MFI[3–0]
1000
Description
Multiplication Factor Integer (MFI)—Defines the integer part of the MF. The MFI can
be any integer from 5 to 15.
Note:
The total MF is limited to a maximum of 15. Therefore, if the MFI is
programmed as 15 (that is, MFI[3–0] = 1111), MFN must equal 0.
MFI[3–0]
MFI Value
0000
5
0001
5
0010
5
0011
5
0100
5
0101
5
0110
6
0111
7
1000
8
.
.
.
1110
14
1111
15
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5-10
Freescale Semiconductor
Programming the Peripherals
6
When peripherals are programmed in a given application, a number of possible modes and
options are available for use. Chapters 6 through 10 describe in detail the possible modes and
configurations for peripheral registers and ports. This chapter presents general guidelines for
initializing the peripherals. These guidelines include a description of how the control registers are
mapped in the DSP56321, data transfer methods that are available when the various peripherals
are used, and information on General-Purpose Input/Output (GPIO) configuration.
6.1 Peripheral Initialization Steps
Each peripheral has its own initialization process. However, all four peripherals share some
common steps, which follow:
1.
Determine the Register values to be programmed, using the following steps:
a.
2.
Find the peripheral register descriptions in the manual.
b. Choose the appropriate modes to configure for a given application.
c. Determine the bit settings for programming those modes.
Make sure the peripheral is in individual reset state or disabled. Peripheral registers
should not be modified while the peripheral is active.
3.
Configure the registers by writing the predetermined values from step 1 into the
appropriate register locations.
4.
Enable the peripheral. Once the peripheral is enabled, it operates according the
programmed modes determined in step 1.
For detailed initialization procedures unique to each peripheral, consult the initialization section
within each peripheral chapter.
6.2 Mapping the Control Registers
The I/O peripherals are controlled through registers mapped to the top 128 words of X-data
memory ($FFFF80–$FFFFFF). Referred to as the internal I/O space, the control registers are
accessed by move (MOVE, MOVEP) instructions and bit-oriented instructions (BCHG, BCLR,
BSET, BTST, BRCLR, BRSET, BSCLR, BSSET, JCLR, JSET, JSCLR, and JSSET). The
contents of the internal X I/O memory space are listed in Appendix B, Programming Reference
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
6-1
Programming the Peripherals
X-Data Memory
$FFFFFF
Internal I/O
Peripherals Control Registers
Memory Space
$FFFF80
External
$FFF000
Internal
Reserved
$FF0000
External
$006000
Internal
X-Data RAM
24K (default)
$000000
Figure 6-1. Memory Mapping of Peripherals Control Registers
6.3 Reading Status Registers
Each peripheral has a read-only status register that indicate the state of the peripheral at a given
time. The HI08, ESSI, and SCI have dedicated status registers. The triple timer has status bits
embedded within a control/status register. Changes in the status bits can generate interrupt
conditions. For example, the HI08 has a host status register with two host flag bits that can be
encoded by the host to generate an interrupt in the DSP.
6.4 Data Transfer Methods
Peripheral I/O on the DSP56321 can be accomplished in three ways:
„
„
„
Polling
Interrupts
DMA
6.4.1 Polling
Polling is the easiest method for data transfers. When polling is chosen, the DSP56321 core
continuously checks a specified register flag waiting for an event to happen. One example would
be setting an overflow flag in one of the Timers. Once the event occurs, the DSP56321 is free to
continue with its next task. However, while it is waiting for the event to occur, the DSP56321
DSP56321 Reference Manual, Rev. 1
6-2
Freescale Semiconductor
Data Transfer Methods
core is not executing any other code. Polling is the easiest transfer method since it does not
require register initialization, but it is also the least efficient use of the DSP core.
Each peripheral has its own set of flags which may be polled to determine when data is ready to
be transferred. For example, the ESSI control registers provide bits that tell the core when data is
ready to be transferred to or from the peripheral. The core polls these bits to determine when to
interact with the peripheral. Similar flags exist for each peripheral.
Example 6-1 shows software polling programmed in an application using the HI08.
Example 6-1. Software Polling
jclr#1,x:M_HSR,*
; loop if HSR[1]:HTDE=0
movey:(TBUFF_PTR)+,x1
; move data to x1
In this example, the core waits until the Host Status Register’s (HSR) Host Transmit Data Empty
(HTDE) flag is set. When the flag is set, the core moves data from Y memory to the X1 register.
6.4.2 Interrupts
Interrupts are more efficient than polling, but interrupts also require additional register
initialization. Polling requires the core to remain busy checking a flag in a specified control
register and therefore does not allow the core to execute other code at the same time. For
interrupts, you can initialize the interrupt so it is triggered off one of the same flags that can also
be polled. Then the core does not have to continuously check a flag. Once the interrupt is
initialized and the flag is set, the core is notified to execute a data transfer. Until the flag is set, the
core can remain busy executing other sections of code.
When an interrupt occurs, the core execution flow jumps to the interrupt start address defined in
Table B-4 in Appendix B, Programming Reference. It executes code starting at the interrupt
address. If it is a short interrupt (i.e., the service routine is two opcodes long), the code
automatically returns to the original program flow after executing two opcodes with no impact to
the pipeline. Otherwise, if a longer service routine is required the programmer can place a
jump-to-subroutine (JSR) instruction at the interrupt service address. In this case, the program
executes that service routine and continues until a return-from-interrupt (RTI) instruction
executes. The execution flow then resumes from the position the program counter was in before
the interrupt was triggered.
Configuring interrupts requires two steps:
1.
Setting up the interrupt routine
a.
The interrupt handler is located at the interrupt starting address.
b.
2.
The interrupt routines can be short (only two opcodes long) or long (more than two
opcodes and requiring a JSR instruction).
Enabling the interrupts
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
6-3
Programming the Peripherals
a.
Set the corresponding bits in the applicable peripheral control register.
b.
c.
Enable peripheral interrupts in the Interrupt Priority Register (IPRP).
Enable global interrupts in the Mode Register (MR) portion of the Status Register
(SR).
Events that change bits in the peripheral control registers can then trigger the interrupt.
Depending on the peripheral, from two to six peripheral interrupt sources are available to the
programmer.
Example 6-2 shows a short interrupt programmed for the HI08. The main program enables the
Host Receive Interrupt in the Host Control Register (HCR). When the interrupt is triggered
during code execution, the core processing jumps to the Host Receive Interrupt routine location
at p:$60 and executes the code there. Since this is a short interrupt, the core returns to normal
code execution after executing the two move instructions, and an RTI instruction is not
necessary.
Example 6-2. Interrupts
bset#M_HRIE,x:M_HCR ; enable host receive interrupt
; Short Interrupt Routine
orgP:$60
movepx:M_HRX,x1
; HI08 Receive Data Full interrupt
movex1,y:(r0)+
6.4.3 DMA
The direct memory access (DMA) controller permits data transfers between internal/external
memory and/or internal/external I/O in any combination without the intervention of the
DSP56321 core. Dedicated DMA address and data buses and internal memory partitioning
ensure that a high level of isolation is achieved so the DMA operation does not interfere with the
core operation or slow it down. The DMA controller moves data to/from the peripheral
transmit/receive registers. The programmer can use the DMA control registers to configure
sources and destinations of data transfers. Depending on the peripheral, there are one to four
peripheral request sources. DMA is the most efficient method of data transfer. Core intervention
is not required after the DMA channel is initialized.
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6-4
Freescale Semiconductor
Data Transfer Methods
Table 6-1. DMA-Accessible Registers
DMA
Block
ESSI
SCI
EFCOP
HI08
Register
Read
Write
TX0
No
Yes
TX1
No
Yes
TX2
No
Yes
RX
Yes
No
SRX
Yes
No
STX
No
Yes
FDIR
No
Yes
FDOR
Yes
No
HTX
No
Yes
HRX
Yes
No
Timer
Example 6-3 shows a DMA configuration for transferring data to the Host Transmit register of
the HI08.
Example 6-3. DMA Transfers
bclr#M_D1L0,x:M_IPRC
; disable DMA1 interrupts
bclr#M_D1L1,x:M_IPRC
movep#TBUFF_START,x:M_DSR1 ; DMA1 source is transmit buffer
movep#M_HTX,x:M_DDR1
; DMA1 destination is HTX
movep#TBUFF_SIZE-1,x:M_DCO1; DMA1 count is the full buffer
movep#INIT_DCR1,x:M_DCR1
; init. DMA1 control register
DMA requires more initialization code and consideration of DMA modes. However, it is the
most efficient use of core resources. After these registers are programmed, you must enable the
DMA by triggering a DMA request off one of the peripheral control flags or enabling it in normal
program flow or an interrupt service routine.
6.4.4 Advantages and Disadvantages
Polling is the easiest method to implement, but it requires a large amount of DSP56321 core
processing power. The core cannot be involved in other processing activities while it is polling
receive and transmit ready bits. Interrupts require more code, but the core can process other
routines while waiting for data I/O. An interrupt is generated when data is ready to be transferred
to or from the peripheral device. DMA requires even less core intervention, and the setup code is
minimal, but the DMA channels must be available.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
6-5
Programming the Peripherals
Note:
Do not use interrupt requests and DMA requests simultaneously.
6.5 General-Purpose Input/Output (GPIO)
The DSP56321 provides 34 bidirectional signals that can be configured as GPIO signals or as
peripheral dedicated signals. No dedicated GPIO signals are provided. All of these signals are
GPIO by default after reset. The control register settings of the DSP56321 peripherals determine
whether these signals function as GPIO or as peripheral dedicated signals. This section tells how
signals can be used as GPIO.
Chapter 2, Signals/Connections details the special uses of the 34 bidirectional signals. These
signals fall into five groups and are controlled separately or as a group:
„
„
„
„
„
Port B: sixteen GPIO signals (shared with the HI08 signals)
Port C: six GPIO signals (shared with the ESSI0 signals)
Port D: six GPIO signals (shared with the ESSI1 signals)
Port E: three GPIO signals (shared with the SCI signals)
Timers: three GPIO signals (shared with the triple timer signals)
6.5.1 Port B Signals and Registers
Each of the 16 Port B signals not used as an HI08 signal can be configured as a GPIO signal.
Three registers control the GPIO functionality of Port B: host control register (HCR), host port
GPIO data register (HDR), and host port GPIO direction register (HDDR). Chapter 7, Host
Interface (HI08) discusses these registers.
DSP56303
Host Interface
(HI08) Port
Non-Multiplexed
Bus
Multiplexed
Bus
Port B GPIO
H[0–7]
HAD[0–7]
PB[0–7]
HA0
HAS/HAS
PB8
HA1
HA8
PB9
HA2
HA9
PB10
HCS/HCS
HA10
PB13
Single DS
HRW
Double DS
HRD/HRD
PB11
HDS/HDS
HWR/HWR
PB12
Single HR
Double HR
HREQ/HREQ
HTRQ/HTRQ
PB14
HACK/HACK
HRRQ/HRRQ
PB15
Figure 6-2. Port B Signals
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6-6
Freescale Semiconductor
General-Purpose Input/Output (GPIO)
6.5.2 Port C Signals and Registers
Each of the six Port C signals not used as an ESSI0 signal can be configured as a GPIO signal.
Three registers control the GPIO functionality of Port C: Port C control register (PCRC), Port C
direction register (PRRC), and Port C data register (PDRC). Chapter 8, Enhanced Synchronous
Serial Interface discusses these registers.
Port C GPIO
DSP56L307
Enhanced Synchronous
Serial Interface Port 0
(ESSI0)
SC0[0–2]
SCK0
PC[0–2]
PC3
SRD0
PC4
STD0
PC5
Figure 6-3. Port C Signals
6.5.3 Port D Signals and Registers
Each of the six Port D signals not used as an ESSI1 signal can be configured as a GPIO signal.
Three registers control the GPIO functionality of Port D: Port D control register (PCRD), Port D
direction register (PRRD), and Port D data register (PDRD). Chapter 8, Enhanced Synchronous
Serial Interface discusses these registers.
Port C GPIO
DSP56L307
Enhanced Synchronous
Serial Interface Port 1
(ESSI1)
SC1[0–2]
SCK1
PD[0–2]
PD3
SRD1
PD4
STD1
PD5
Figure 6-4. Port D Signals
6.5.4 Port E Signals and Registers
Each of the three Port E signals not used as an SCI signal can be configured as a GPIO signal.
Three registers control the GPIO functionality of Port E: Port E control register (PCRE), Port E
direction register (PRRE), and Port E data register (PDRE). Chapter 9, Serial Communication
Interface discusses these registers.
DSP56L307
Port E GPIO
RXD
Serial
Communications
Interface (SCI) Port
TXD
PE0
PE1
SCLK
PE2
Figure 6-5. Port E Signals
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
6-7
Programming the Peripherals
6.5.5 Triple Timer Signals and Registers
Each of the three triple timer interface signals (TIO0–TIO2) not used as a timer signal can be
configured as a GPIO signal. Each signal is controlled by the appropriate timer control status
register (TCSR0–TCSR2). Chapter 10, Triple Timer Module discusses these registers.
DSP56L307
Timer GPIO
TIMERS
TIO0
TIO1
TIO0
TIO1
TIO2
TIO2
Figure 6-6. Triple Timer Signals
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6-8
Freescale Semiconductor
Host Interface (HI08)
7
The host interface (HI08) is a byte-wide, full-duplex, double-buffered parallel port that can
connect directly to the data bus of a host processor. The HI08 supports a variety of buses and
provides glueless connection with a number of industry-standard microcomputers,
microprocessors, and DSPs. The HI08 signals not used to interface to the host can be configured
as GPIO signals, up to a total of 16.
7.1 Features
The HI08 host is a slave device that operates asynchronously to the DSP core and host clocks.
Thus, the HI08 peripheral has a host processor interface and a DSP core interface. This section
lists the features of the host processor and DSP core interfaces.
7.1.1 DSP Core Interface
„
„
„
„
Mapping:
— Registers are directly mapped into eight internal X data memory locations.
Data word:
— DSP56321 24-bit (native) data words are supported, as are 8-bit and 16-bit words.
Handshaking protocols:
— Software polled
— Interrupt driven
— Core DMA accesses
Instructions:
— Memory-mapped registers allow the standard MOVE instruction to transfer data
between the DSP56321 and external hosts.
— A special MOVEP instruction for I/O service capability using fast interrupts.
— Bit addressing instructions (for example, BCHG, BCLR, BSET, BTST, JCLR, JSCLR,
JSET, JSSET) simplify I/O service routines.
7.1.2 Host Processor Interface
„
Sixteen signals support non-multiplexed or multiplexed buses:
— H[0–7]/HAD[0–7] host data bus (H[0–7]) or host multiplexed address/data bus (HAD[0–7])
— HAS/HA0 address strobe (HAS) or host address line (HA0)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-1
Host Interface (HI08)
—
—
—
—
—
—
—
Note:
„
„
„
„
„
„
HA8/HA1
host address line (HA8) or host address line (HA1)
HA9/HA2 host address line (HA9) or host address line (HA2)
HRW/HRD read/write select (HRW) or read strobe (HRD)
HDS/HWR data strobe (HDS) or write strobe (HWR )
HCS/HA10 host chip select (HCS) or host address line (HA10)
HREQ/HTRQ host request (HREQ) or host transmit request (HTRQ)
HACK/HRRQ host acknowledge (HACK) or host receive request (HRRQ)
The signals in the above list that are shown as asserted low (for example, HRD) all have
programmable polarity. The default value following reset is shown in the above list.
Mapping:
— HI08 registers are mapped into eight consecutive locations in the host’s external bus
address space.
— The HI08 acts as a memory or I/O-mapped peripheral for microprocessors,
microcontrollers, and so forth.
Transfer modes:
— Mixed 8-bit, 16-bit, and 24-bit data transfers
• DSP-to-host
• Host-to-DSP
— Host command
Handshaking protocols:
— Software polled
— Interrupt-driven (Interrupts are compatible with most processors, including the
MC68000, 8051, HC11, and Hitachi H8.)
Data word: 8 bits
Dedicated interrupts:
— Separate request lines for each interrupt source
— Special host commands force DSP core interrupts under host processor control. These
commands are useful for
• Real-time production diagnostics
• Creation of a debugging window for program development
• Host control protocols
Interface capabilities:
— Glueless interface (no external logic required) to
• Freescale HC11
• Hitachi H8
• 8051 family
• Thomson P6 family
DSP56321 Reference Manual, Rev. 1
7-2
Freescale Semiconductor
Host Port Signals
— Minimal glue logic (pull-ups, pull-downs) required to interface to
• ISA bus
• Freescale 68K family
• Intel X86 family
7.2 Host Port Signals
The host port signals are discussed in Chapter 2, Signals/Connections. Each host port signal can
be programmed as a host port signal or as a GPIO signal, PB[0–15]. See Table 7-1 through
Table 7-3.
Table 7-1. HI08 Signal Definitions for Operational Modes
HI08 Port Signal
Multiplexed Address/Data Bus Mode
Non-multiplexed Bus Mode
GPIO Mode
HAD[0–7]
HAD[0–7]
H[0–7]
PB[0–7]
HAS/HA0
HAS/HAS
HA0
PB8
HA8/HA1
HA8
HA1
PB9
HA9/HA2
HA9
HA2
PB10
HCS/HA10
HA10
HCS/HCS
PB13
Table 7-2. HI08 Data Strobe Signals
HI08 Port
Signal
Single Strobe Mode
Dual Strobe Mode
GPIO Mode
HRW/HRD
HRW
HRD/HRD
PB11
HDS/HWR
HDS/HDS
HWR/HWR
PB12
Table 7-3. HI08 Host Request Signals
HI08 Port
Signal
Single Host Request Mode
Double Host Request
Mode
GPIO Mode
HREQ/
HTRQ
HREQ/HREQ
HTRQ/HTRQ
PB14
HACK/
HRRQ
HACK/HACK
HRRQ/HRRQ
PB15
The HI08 port can operate in multiplexed or non-multiplexed mode. In multiplexed mode
(HPCR[11]:HMUX=1), the lower eight address signals multiplex with the eight data lines. In
non-multiplexed mode (HPCR[11]:HMUX=0), the HI08 requires a chip select signal and three
address lines to select one of the eight registers accessible to the host. Eight lines are used for
data. The HI08 port can also be programmed to use a single or dual read/write data strobe and
single or double host request.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-3
Host Interface (HI08)
Software and hardware resets clear all DSP-side control registers and configure the HI08 as
GPIO. To select GPIO functions, clear HPCR bits 6 through 1; to select other HI08 functions, set
those same bits. If the HI08 is in GPIO mode, the HDDR configures each corresponding signal in
the HDR as an input signal if the HDDR bit is cleared or as an output signal if the HDDR bit is
set. For details, see Section 7.6.3, Host Data Direction Register (HDDR), on page 7-14 and
Section 7.6.4, Host Data Register (HDR), on page 7-15.
7.3 Overview
The HI08 is partitioned into two register banks, as Figure 7-1 shows. The host-side bank is
accessible only to the host, and the DSP-side register bank is accessible only to the DSP core. For
the host, the HI08 appears as eight byte-wide locations mapped in its external address space. The
DSP-side registers appear to the DSP core as six 24-bit registers mapped into internal I/O X
memory space and therefore accessible via standard DSP56300 instructions and addressing
modes. In GPIO mode, two additional registers (HDDR and HDR) are related to the HI08
peripheral. The separate receive and transmit data paths are double buffered for efficient, high
speed asynchronous transfers. The host-side transmit data path (host writes) is also the DSP-side
receive path; the host-side receive data path (host reads) is also the DSP-side transmit path. The
Receive (RXH:RXM:RXL) and Transmit Data Registers (TXH:TXM:TXL) use the same host
address. During host writes to these addresses, the data is transferred to the Transmit Data
Registers while reads are performed from the Receive Data Registers.
7.4 Operation
The HI08 is a slave-only device, so the host is the master of all bus transfers. In host-to-DSP
transfers, the host writes data to the Transmit Data Registers (TXH:TXM:TXL). In DSP-to-host
transfers the host reads data from the Receive Data Registers (RXH:RXM:RXL). The DSP side
has access only to the Host Receive Data Register (HRX) and the Host Transmit Data Register
(HTX). Data automatically moves between the host-side data registers and the DSP-side data
registers when it is available. This double-buffered mechanism allows for fast data transfers but
creates a “pipeline” that can either stall communication (if the pipeline is either full or empty) or
cause erroneous data transfers (new data to be overwritten or old data to be read twice). The HI08
port has several handshaking mechanisms to counter these buffering effects.
Suppose the host is writing several pieces of data to the HI08 port. The host first uses one of the
handshaking protocols to determine whether any data previously written to the Transmit Data
Registers (TXH:TXM:TXL) has successfully transferred to the DSP side. If the host-side
Transmit Data Registers (TXH:TXM:TXL) are empty, the host writes the data to these registers.
The transfer to the DSP-side Host Receive Data Register (HRX) occurs only if HRX is empty
(that is, the DSP has read it). The DSP core then uses an appropriate handshaking protocol to
move data from the HRX to the receiving buffer or register. Without handshaking, the host might
overwrite data not transferred to the DSP side or the DSP might receive stale data.
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7-4
Freescale Semiconductor
Operation
DSP-Side Registers
Control Registers
Data Registers
HCR = Host Control Register
HTX = Host Transmit Register
HSR = Host Status Register
HRX = Host Receive Register
HPCR = Host Port Control Register
HDDR = Host Data Direction Register
HBAR = Host Base Address Register
HDR = Host Data Register
Core DMA Data Bus
DSP Peripheral Data Bus
24
HCR
24
HSR
24
HDDR
24
24
HDR
24
HBAR
24
HPCR
24
24
HTX
Address
Comparator
24
DSP
Side
HRX
24
24
5
3
ISR
ICR
8
CVR
8
8
IVR
8
Latch
8
3
RXH
RXM
RXL
TXH
TXM
8
8
8
8
8
TXL
Host
Side
8
HOST Bus
Host-Side Registers
Data Registers
Control Registers
ISR = Interface Status Register
ICR = Interface Control Register
RXH = Receive Register High
RXM = Receive Register Middle
CVR = Command Vector Register
RXL = Receive Register Low
IVR = Interrupt Vector Register
TXH = Transmit Register High
TXM = Transmit Register Middle
TXL = Transmit Register Low
Figure 7-1. HI08 Block Diagram
Similarly, when the host performs multiple reads from the HI08 port Receive Data Registers
(RXH:RXM:RXL), the DSP side uses an appropriate handshaking protocol to determine whether
any data previously written to the Host Transmit Register (HTX) has successfully transferred to
the host-side registers. If HTX is empty, the DSP writes the data to this register. Data transfers to
the host-side Receive Data Registers (RXH:RXM:RXL) occur only if they are empty (that is, the
host has read them). The host can then use any of the available handshaking protocols to
determine whether more data is ready to be read.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-5
Host Interface (HI08)
The DSP56321 HI08 port offers the following handshaking protocols for data transfers with the
host:
„
„
„
„
Software polling
Interrupts
Core DMA access
Host requests
The choice of which protocol to use is based on such system constraints as the amount of data to
be transferred, the timing requirements for the transfer, and the availability of such resources as
processing bandwidth and DMA channels. All of these constraints are discussed in the following
sections. The transfers described here occur asynchronously between the host and the DSP; each
transferring data at its own pace. However, use of the appropriate handshaking protocol allows
data transfers to occur at optimum rates.
7.4.1 Software Polling
Software polling is the simplest data transfer method to use, but it demands the greatest amount
of the core’s processing power. Status bits are provided for the host or the DSP core to test and
determine if the data registers are empty or full. However, the DSP core cannot be involved in
other processing activities while it is polling these status bits.
On the DSP side, for transfers from the DSP to the host (host reads), the DSP core must
determine the state of Host Transmit Data register (HTX). In transfers from the host to the DSP
(host writes), the DSP side should determine the state of the Host Receive Data Register (HRX).
Thus, two bits are provided to the core for polling:
„
„
the Host Transmit Data Empty (HTDE) bit in the Host Status register (HSR[1]:HTDE)
the Host Receive Data Full (HRDF) bit in the Host Status register (HSR[0]:HRDF)
A similar mechanism is available on the host-side to determine the state of the Transmit Registers
(TXH:TXM:TXL) and Receive Registers (RXH:RHM:RHL). Two bits are provided to the host
for polling:
„
„
the Transmit Data Empty (TXDE) bit in the Interface Status Register (ISR[1]:TXDE)
the Receive Data Full (RXDF) bit in the Interface Status Register (ISR[0]:RXDF)
The HI08 also offers four general-purpose flags for communication between the host and the
DSP. The DSP-side uses the HSR Host Flag bits (HCR[4–3]=HF[3–2]) to pass
application-specific information to the host. The status of HF3–HF2 is reflected in the host-side
ISR Host Flag bits (ISR[4–3]=HF[3–2]). Similarly, the host side can use the ICR Host Flag bits
(ICR[4–3]=HF[1–0]) to pass application-specific information to the DSP. The status of HF[1–0]
is reflected in the DSP-side HSR Host Flag bits
(HSR[4–3]=HF[1–0]).
DSP56321 Reference Manual, Rev. 1
7-6
Freescale Semiconductor
Operation
7.4.2 Core Interrupts and Host Commands
The HI08 can request interrupt service from the DSP56321 core. The DSP56321 core interrupts
are internal and do not require the use of an external interrupt signal. When the appropriate
interrupt enable bit in the HCR is set, an interrupt condition caused by the host interface sets the
appropriate bit in the HSR, generating an interrupt request to the DSP56321 interrupt controller
(see Figure 7-2). The DSP56321 acknowledges interrupts by jumping to the appropriate interrupt
service routine. The following DSP core interrupts are possible from the HI08 peripheral:
„
„
„
Host command
Transmit data register empty
Receive data register full
These interrupts are maskable via the Host Receive Interrupt Enable bit (HCR[0]=HRIE), the
Host Transmit Interrupt Enable bit (HCR[1]=HTIE), and the Host Command Interrupt Enable bit
(HCR[2]=HCIE), respectively. Receive Data Full and Transmit Data Empty interrupts move data
to/from the HTX and HRX data registers. The DSP interrupt service routine must read or write
the appropriate HI08 data register (HRX or HTX) to clear the interrupt condition.
Enable
15
X:HCR
HF3
HF2
0
HCIE HTIE HRIE HCR
DSP Core Interrupts
Receive Data Full
Transmit Data Empty
Host Command
15
X:HSR
0
HF1
HF0
HCP HTDE HRDF HSR
Status
Figure 7-2. HI08 Core Interrupt Operation
Host commands allow the host to issue command requests to the DSP by selecting any of 128
DSP interrupt routines for execution. For example, the host may issue a command via the HI08
that sets up and enables a DMA transfer. The DSP56321 processor has reserved interrupt vector
addresses for application-specific service routines. However, this flexibility is independent of the
data transfer mechanisms in the HI08 and allows the host to force execution of any interrupt
handler (for example, SSI, SCI, IRQx, and so on).
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-7
Host Interface (HI08)
To enable Host Command interrupts, the HCR[2]=HCIE bit is set on the DSP side. The host then
uses the Command Vector Register (CVR) to start an interrupt routine. The host sets the Host
Command bit (CVR[7]=HC) to request the command interrupt and the seven Host Vector bits
CVR[6–0]=HV[6–0] to select the interrupt address to be used. When the DSP core recognizes the
host command interrupt, the address of the interrupt taken is 2xHV. For host command interrupts,
the interrupt acknowledge from the DSP56321 program controller clears the pending interrupt
condition.
Note:
When the DSP enters Stop mode, the HI08 pins are electrically disconnected
internally, thus disabling the HI08 until the core leaves Stop mode. Do not issue a
STOP command via the HI08 unless some other mechanism for exiting this mode is
provided.
7.4.3 Core DMA Access
The DSP56300 family Direct Memory Access (DMA) controller permits transfers between
internal or external memory and I/O without any core intervention. A DMA channel can be set up
to transfer data to/from the HTX and HRX data registers, freeing the core to use its processing
power on functions other than polling or interrupt routines for the HI08. DMA may well be the
best method to use for data transfers, but it requires that one of the six DMA channels be
available for use. Two HI08 DMA sources are possible, as Table 7-4 shows. Refer to the
DSP56300 Family Manual to learn about DMA accesses.
Table 7-4. DMA Request Sources
Note:
Requesting Device
DCRx[15–11]=DRS[4–0]
Host Receive Data Full (HRDF=1)
10011
Host Transmit Data Empty (HTDE=1)
10100
DMA transfers do not access the host bus. The host must determine when data is
available in the host-side data registers using an appropriate polling mechanism.
7.4.4 Host Requests
A set of signal lines allow the HI08 to request service from the host. The request signal lines
normally connect to the host interrupt request pins (IRQx) and indicate to the host when the DSP
HI08 port requires service. The HI08 can be configured to use either a single Host Request
(HREQ) line for both receive and transmit requests or two signal lines, a Host Transmit Request
(HTRQ) and a Host Receive Request (HRRQ), for each type of transfer. Host requests are
enabled on both the DSP-side and host-side. On the DSP side, the HPCR Host Request Enable bit
(HPCR[4]=HREN) is set to enable host requests. On the host side, clearing the ICR Double Host
Request bit (ICR[2]=HDRQ) configures the HI08 to use a single request line (HREQ). Setting
the ICR[2]=HDRQ bit enables both transmit and request lines to be used. Further, the host uses
DSP56321 Reference Manual, Rev. 1
7-8
Freescale Semiconductor
Operation
the ICR Receive Request Enable bit (ICR[0]=RREQ) and the ICR Transmit Request Enable bit
(ICR[1]=TREQ) to enable receive and transmit requests, respectively. When host requests are
enabled, the host request pins operate as shown in Figure 7-3.
Status
7
$2 HREQ
0
0
HF3
HF2
TRDY
0
TXDE RXDF ISR
Host Request
Signals
Host Request
Asserted
HRRQ
HREQ
HTRQ
7
$0
0
INIT
0
0
HF1
HF0 HLEND TREQ RREQ ICR
Enable
Figure 7-3. HI08 Host Request Structure
Table 7-5 shows the operation of the HREQ pin when a single request line is used. The host can
test these ICR bits to determine the interrupt source.
Table 7-5. HREQ Pin Operation In Single Request Mode (ICR[2]=HDRQ=0)
ICR[1]=TREQ
ICR[0]=RREQ
HREQ Pin
0
0
No interrupts
0
1
RXDF request enabled
1
0
TXDE request enabled
1
1
RXDF and TXDE request enabled
Table 7-6 shows the operation of the transmit request (HTRQ) and receive request (HRRQ) lines
with dual host requests enabled.
Table 7-6. HTRQ and HRRQ Pin Operation In Double Request Mode (ICR[2]=HDRQ=1)
ICR[1]=TREQ
ICR[0]=RREQ
HTRQ Pin
HRRQ Pin
0
0
No interrupts
No interrupts
0
1
No interrupts
RXDF request enabled
1
0
TXDE Request enabled
No interrupts
1
1
TXDE Request enabled
RXDF request enabled
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-9
Host Interface (HI08)
7.4.5 Endian Modes
The Host Little Endian bit in the host-side Interface Control Register (ICR[5]=HLEND) allows
the host to access the HI08 data registers in Big Endian or Little Endian mode. In Little Endian
mode (HLEND=1), a host transfer occurs as shown in Figure 7-4.
HTX/HRX Bit Number: 23
0
aa
bb
cc
DSP side
Host side
Host 32-bit
internal register
Low Byte
cc
bb
aa
Host bus address:
$5
$6
$7
cc
bb
aa
xx
High Byte
(read/write last!)
Figure 7-4. HI08 Read and Write Operations in Little Endian Mode
The host can transfer one byte at a time, so a 24-bit datum would be transferred using three store
(or load) byte operations, ensuring that the data byte at host bus address $7 is written last since
this causes the transfer of the data to the DSP-side HRX. However, the host bus controller may be
sophisticated enough that the host can transfer all bytes in a single operation (instruction). For
example, in the PowerPC MPC860 processor, the General-Purpose Controller Module (GPCM)
in the memory controller can be programmed so that the host can execute a single read (load
word, LDW) or write (store word, STW) instruction to the HI08 port and cause four byte
transfers to occur on the host bus. The 32-bit datum transfer shown in Figure 7-4 has byte data xx
written to HI08 address $4, byte aa to address $5, byte bb to address $6 and byte cc to address $7
(this assumes the 24-bit datum is contained in the lower 24 bits of the host’s 32-bit data register
as shown). A similar operation occurs when the HI08 is initialized in Big Endian mode by
clearing the Host Little Endian bit (ICR[5]=HLEND). Big Endian mode is depicted in Figure
7-5.
DSP56321 Reference Manual, Rev. 1
7-10
Freescale Semiconductor
Boot-up Using the HI08 Host Port
HTX/HRX Register: 23
0
aa
cc
bb
DSP side
Host side
High Byte
aa
bb
cc
Host bus address:
$5
$6
$7
bb
cc
Host 32-bit
internal register
xx
aa
Low Byte
(read/write last!)
Figure 7-5. HI08 Read and Write Operations in Big Endian Mode
7.5 Boot-up Using the HI08 Host Port
The DSP56300 core has eight bootstrap operating modes to start up after reset. As the processor
exits the Reset state the value at the external mode pins MODA/IRQA, MODB/IRQB, MODC/IRQC and
MODD/IRQD are loaded into the Chip Operating Mode bits (MA, MB, MC and MD) of the
Operating Mode Register (OMR). These bits determine the bootstrap operating mode. Modes C,
D, E and F use the HI08 host port to bootstrap the application code to the DSP. Table 7-7
describes these modes.
Table 7-7. HI08 Boot Modes
Mode
MODD
MODC
MODB
MODA
HI08 Bootstrap Description
C
1
1
0
0
ISA/DSP5630x mode
D
1
1
0
1
HC11 non-multiplexed bus mode
E
1
1
1
0
8051 multiplexed bus mode
F
1
1
1
1
MC68302 bus mode
The bootstrap program is factory-programmed into an internal 192-word by 24-bit bootstrap
ROM at locations $FF0000–$FF00BF of P memory. This program can load program RAM
segment from the HI08 host port. When any of the modes in the preceding table are used, the core
begins executing the bootstrap program and configures the HI08 based on the OMR mode bits.
The bootstrap program then expects the following data sequence when the user program is
downloaded from the HI08:
1.
Three bytes (least significant byte first) indicating the number of 24-bit program words
to be loaded.
2.
Three bytes (least significant byte first) indicating the 24-bit starting address in
P-memory to load the user's program.
3.
The user program (three bytes, least significant byte first, for each program word).
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-11
Host Interface (HI08)
When the bootstrap program finishes loading the specified number of words, it jumps to the
specified starting address and executes the loaded program.
7.6 DSP Core Programming Model
The DSP56300 core treats the HI08 as a memory-mapped peripheral occupying eight 24-bit
words in X data memory space. The DSP can use the HI08 as a normal memory-mapped
peripheral, employing either standard polled or interrupt-driven programming techniques.
Separate transmit and receive data registers are double-buffered to allow the DSP and host
processor to transfer data efficiently at high speed. Direct memory mapping allows the
DSP56321 core to communicate with the HI08 registers using standard instructions and
addressing modes. In addition, the MOVEP instruction allows direct data transfers between
DSP56321 internal memory and the HI08 registers or vice versa.
There are two types of host processor registers, data and control, with eight registers in all. The
DSP core can access all eight registers, but the external host cannot. The following data registers
are 24-bit registers used for high-speed data transfers by the DSP core.
„
„
Host data receive register (HRX), on page 7-19
Host data transmit register (HTX), on page 7-19
The DSP-side control registers are 16-bit registers that control HI08 functionality:
„
„
„
„
„
„
Host control register (HCR), on page 7-12
Host status register (HSR), on page 7-13
Host GPIO data direction register (HDDR), on page 7-14
Host GPIO data register (HDR), on page 7-15
Host base address register (HBAR), on page 7-15
Host port control register (HPCR), on page 7-16
Both hardware and software resets disable the HI08. After reset, the HI08 signals are configured
as GPIO and disconnected from the DSP56300 core (that is, left floating).
7.6.1 Host Control Register (HCR)
This read/write register controls the HI08 interrupt operation. Initialization values for HCR bits
are presented in Section 7.6.9, DSP-Side Registers After Reset, on page 7-20.
15
14
13
12
11
10
9
8
7
6
5
4
3
HF3
HF2
2
1
0
HCIE HTIE HRIE
—Reserved bit; read as 0; write to 0 for future compatibility.
DSP56321 Reference Manual, Rev. 1
7-12
Freescale Semiconductor
DSP Core Programming Model
Table 7-8. Host Control Register (HCR) Bit Definitions
Bit Number
Bit Name
15–5
Reset Value
Description
0
Reserved. Write to 0 for future compatibility.
4–3
HF[3 –2]
0
Host Flags 2, 3
General-purpose flags for DSP-to-host communication. The DSP core can
set or clear HF[3–2]. The values of HF[3–2] are reflected in the interface
status register (ISR); that is, if they are modified by the DSP software, the
host processor can read the modified values by reading the ISR. These
two general-purpose flags can be used individually or as encoded pairs in
a simple DSP-to-host communication protocol, implemented in both the
DSP and the host processor software. The bit value is indeterminate after
an individual reset.
2
HCIE
0
Host Command Interrupt Enable
Generates a host command interrupt request if the host command
pending (HCP) status bit in the HSR is set. If HCIE is cleared, HCP
interrupts are disabled. The interrupt address is determined by the host
command vector register (CVR).
NOTE: If more than one interrupt request source is asserted and enabled
(for example, HRDF is set, HCP is set, HRIE is set, and HCIE is set), the
HI08 generates interrupt requests according to priorities shown here. The
bit value is indeterminate after an individual reset.
Priority
Interrupt Source
Highest
Host Command (HCP = 1)
Transmit Data (HTDE = 1)
Lowest
Receive Data (HRDF = 1)
1
HTIE
0
Host Transmit Interrupt Enable
Generates a host transmit data interrupt request if the host transmit data
empty (HTDE) bit in the HSR is set. The HTDE bit is set when data is
transferred from the HTX to the RXH, RXM, or RXL registers. If HTIE is
cleared, HTDE interrupts are disabled. The bit value is indeterminate after
an individual reset.
0
HRIE
0
Host Receive Interrupt Enable
Generates a host receive data interrupt request if the host receive data full
(HRDF) bit in the host status register (HSR, Bit 0) is set. The HRDF bit is
set when data is transferred to the HRX from the TXH, TXM, or TXL
registers. If HRIE is cleared, HRDF interrupts are disabled. The bit value is
indeterminate after an individual reset.
7.6.2 Host Status Register (HSR)
The HSR is a 16-bit read-only status register by which the DSP reads the HI08 status and flags.
The host processor cannot access it directly. The initialization values for the HSR bits are
discussed in Section 7.6.9, DSP-Side Registers After Reset, on page 7-20.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-13
Host Interface (HI08)
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
HF1
HF0
HCP
HTD
E
HRD
F
—Reserved bit; read as 0; write to 0 for future compatibility.
Figure 0-1. Host Status Register (HSR) (X:$FFFFC3)
Table 7-9. Host Status Register (HSR) Bit Definitions
Bit Number
Bit Name
Reset Value
15–5
Description
0
Reserved. Write to 0 for future compatibility.
4–3
HF[1–0]
0
Host Flags 0, 1
General-purpose flags for host-to-DSP communication. These bits reflect
the status of host flags HF[1–0] in the ICR on the host side. These two
general-purpose flags can be used individually or as encoded pairs in a
simple host-to-DSP communication protocol, implemented in both the
DSP and the host processor software.
2
HCP
0
Host Command Pending
Reflects the status of the CVR[HC] bit. When set, it indicates that a host
command interrupt is pending. HI08 hardware clears HC and HCP when
the DSP core services the interrupt request. If the host clears HC, HCP is
also cleared.
1
HTDE
0
Host Transmit Data Empty
Indicates that the host transmit data register (HTX) is empty and can be
written by the DSP core. HTDE is set when the HTX register is transferred
to the RXH:RXM:RXL registers. The host processor can also set HTDE
using the initialize function. HTDE is cleared when the DSP core writes to
HTX.
0
HRDF
0
Host Receive Data Full
Indicates that the host receive data register (HRX) contains data from the
host processor. HRDF is set when data is transferred from the
TXH:TXM:TXL registers to the HRX register. The host processor can also
clear HRDF using the initialize function.
7.6.3 Host Data Direction Register (HDDR)
The HDDR controls the direction of the data flow for each of the HI08 signals configured as
GPIO. Even when the HI08 functions as the host interface, its unused signals can be configured
as GPIO signals. For information on the HI08 GPIO configuration options, see Section 7.2, Host
Port Signals, on page 7-3. If Bit DRxx is set, the corresponding HI08 signal is configured as an
output signal. If Bit DRxx is cleared, the corresponding HI08 signal is configured as an input
signal. Hardware and software reset clear the HDDR bits.
15
14
13
12
11
10
DR15 DR14 DR13 DR12 DR11 DR10
9
8
7
6
5
4
3
2
1
0
DR9
DR8
DR7
DR6
DR5
DR4
DR3
DR2
DR1
DR0
DSP56321 Reference Manual, Rev. 1
7-14
Freescale Semiconductor
DSP Core Programming Model
7.6.4 Host Data Register (HDR)
The HDR register (X:$FFFFC9) holds the data value of the corresponding bits of the HI08
signals configured as GPIO signals. The functionality of Dxx depends on the corresponding
HDDR bit (that is, DRxx).The host processor can not access the Host Data Register (HDR).
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Table 7-10. HDR and HDDR Functionality
HDDR
HDR
Dxx
DRxx
GPIO Signal1
Non-GPIO Signal1
0
Read-only bit—The value read is the binary value of the
signal. The corresponding signal is configured as an
input.
Read-only bit—Does not contain significant data.
1
Read/write bit— The value written is the value read. The
corresponding signal is configured as an output and is
driven with the data written to Dxx.
Read/write bit— The value written is the value read.
1. Defined by the selected configuration.
7.6.5 Host Base Address Register (HBAR)
In multiplexed bus modes, HBAR selects the base address where the host-side registers are
mapped into the host bus address space. The address from the host bus is compared with the base
address as programmed in the Base Address Register. An internal chip select is generated if a
match is found. Figure 7-6 shows how the chip-select logic uses HBAR.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
BA10
BA9
BA8
BA7
BA6
BA5
BA4
BA3
—Reserved bit, read as 0, write to 0 for future compatibility.
Table 7-11. Host Base Address Register (HBAR) Bit Definitions
Bit Number
Bit Name
15–8
7–0
Reset Value
0
BA[10–3]
$80
Description
Reserved. Write to 0 for future compatibility.
Base Address
Reflect the base address where the host-side registers are mapped into the
bus address space.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-15
Host Interface (HI08)
HAD[0–7]
HAS
A[3–7]
Comparator
Latch
HA[8–10]
Base
Address
Register
DSP Peripheral
Data Bus
8 bits
Chip select
Figure 7-6. Self Chip-Select Logic
7.6.6 Host Port Control Register (HPCR)
The HPCR is a read/write control register that controls the HI08 operating mode. HPCR bit
initialization values are discussed in Section 7.6.9, DSP-Side Registers After Reset, on page
7-20. Hardware and software reset clear the HPCR bits.
15
14
HAP
HRP
13
12
11
10
9
8
7
HCSP HDDS HMUX HASP HDSP HROD
6
HEN
5
4
3
2
1
0
HAEN HREN HCSEN HA9EN HA8EN HGEN
—Reserved bit, read as 0; write to 0 for future compatibility.
To assure proper operation of the DSP56321, the HPCR bits HAP, HRP, HCSP, HDDS, HMUX,
HASP, HDSP, HROD, HAEN, and HREN should be changed only if HEN is cleared. Similarly,
the HPCR bits HAP, HRP, HCSP, HDDS, HMUX, HASP, HDSP, HROD, HAEN, HREN,
HCSEN, HA9EN, and HA8EN should not be set when HEN is set nor at the time HEN is set.
Table 7-12. Host Port Control Register (HPCR) Bit Definitions
Bit Number
Bit Name
Reset Value
Description
15
HAP
0
Host Acknowledge Polarity
If HAP is cleared, the host acknowledge (HACK) signal is configured as an
active low input. The HI08 drives the contents of the IVR onto the host bus
when the HACK signal is low. If the HAP bit is set, the HACK signal is
configured as an active high input. The HI08 outputs the contents of the IVR
when the HACK signal is high.
14
HRP
0
Host Request Polarity
Controls the polarity of the host request signals. In single host request mode
(that is, when HDRQ is cleared in the ICR), if HRP is cleared and host
requests are enabled (that is, if HREN is set and HEN is set), then the HREQ
signal is an active low output. If HRP is set and host requests are enabled,
the HREQ signal is an active high output. In the double host request mode
(that is, when HDRQ is set in the ICR), if HRP is cleared and host requests
are enabled (that is, if HREN is set and HEN is set), then the HTRQ and
HRRQ signals are active low outputs. If HRP is set and host requests are
enabled, the HTRQ and HRRQ signals are active high outputs.
DSP56321 Reference Manual, Rev. 1
7-16
Freescale Semiconductor
DSP Core Programming Model
Table 7-12. Host Port Control Register (HPCR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
13
HCSP
0
Host Chip Select Polarity
If the HCSP bit is cleared, the host chip select (HCS) signal is configured as
an active low input and the HI08 is selected when the HCS signal is low. If
the HCSP signal is set, HCS is configured as an active high input and the
HI08 is selected when the HCS signal is high.
12
HDDS
0
Host Dual Data Strobe
If the HDDS bit is cleared, the HI08 operates in single-strobe bus mode. In
this mode, the bus has a single data strobe signal for both reads and writes.
If the HDDS bit is set, the HI08 operates in dual strobe bus mode. In this
mode, the bus has two separate data strobes: one for data reads, the other
for data writes. See Figure 7-7 on page -19 and Figure 7-8 on page -19 for
details on dual and single strobe modes.
11
HMUX
0
Host Multiplexed Bus
If HMUX is set, the HI08 operates in multiplex mode, latching the lower
portion of a multiplexed address/data bus. In this mode the internal address
line values of the host registers are taken from the internal latch. If HMUX is
cleared, it indicates that the HI08 is connected to a non-multiplexed type of
bus. The values of the address lines are then taken from the HI08-dedicated
address signals.
10
HASP
0
Host Address Strobe Polarity
If HASP is cleared, the host address strobe (HAS) signal is an active low
input, and the address on the host address/data bus is sampled when the
HAS signal is low. If HASP is set, HAS is an active-high address strobe
input, and the address on the host address or data bus is sampled when the
HAS signal is high.
9
HDSP
0
Host Data Strobe Polarity
If HDSP is cleared, the data strobe signals are configured as active low
inputs, and data is transferred when the data strobe is low. If HDSP is set,
the data strobe signals are configured as active high inputs, and data is
transferred when the data strobe is high. The data strobe signals are either
HDS by itself or both HRD and HWR together.
8
HROD
0
Host Request Open Drain
Controls the output drive of the host request signals. In the single host
request mode (that is, when HDRQ is cleared in ICR), if HROD is cleared
and host requests are enabled (that is, if HREN is set and HEN is set in the
host port control register (HPCR)), then the HREQ signal is always driven by
the HI08. If HROD is set and host requests are enabled, the HREQ signal is
an open drain output. In the double host request mode (that is, when HDRQ
is set in the ICR), if HROD is cleared and host requests are enabled (that is,
if HREN is set and HEN is set in the HPCR), then the HTRQ and HRRQ
signals are always driven. If HROD is set and host requests are enabled, the
HTRQ and HRRQ signals are open drain outputs.
0
Reserved. Write to 0 for future compatibility.
0
Host Enable
If HEN is set, the HI08 operates as the host interface. If HEN is cleared, the
HI08 is not active, and all the HI08 signals are configured as GPIO signals
according to the value of the HDDR and HDR.
7
6
HEN
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-17
Host Interface (HI08)
Table 7-12. Host Port Control Register (HPCR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
5
HAEN
0
Host Acknowledge Enable
Controls the HACK signal. In the single host request mode (HDRQ is cleared
in the ICR), if HAEN and HREN are both set, HACK/HRRQ is configured as
the host acknowledge (HACK) input. If HAEN or HREN is cleared,
HACK/HRRQ is configured as a GPIO signal according to the value of the
HDDR and HDR. In the double host request mode (HDRQ is set in the ICR),
HAEN is ignored.
4
HREN
0
Host Request Enable
Controls the host request signals. If HREN is set and the HI08 is in the single
host request mode (that is, if HDRQ is cleared in the host interface control
register (ICR)), then HREQ/HTRQ is configured as the host request (HREQ)
output. If HREN is cleared, HREQ/HTRQ and HACK/HRRQ are configured
as GPIO signals according to the value of the HDDR and HDR.
If HREN is set in the double host request mode (that is, if HDRQ is set in the
ICR), HREQ/HTRQ is configured as the host transmit request (HTRQ) output
and HACK/HRRQ as the host receive request (HRRQ) output. If HREN is
cleared, HREQ/HTRQ and HACK/HRRQ are configured as GPIO signals
according to the value of the HDDR and HDR.
3
HCSEN
0
Host Chip Select Enable
If the HCSEN bit is set, HCS/HA10 is a host chip select (HCS) in the
non-multiplexed bus mode (that is, when HMUX is cleared) and host address
line 10 (HA10) in the multiplexed bus mode (that is, when HMUX is set). If
this bit is cleared, HCS/HA10 is configured as a GPIO signal according to the
value of the HDDR and HDR.
2
HA9EN
0
Host Address Line 9 Enable
If HA9EN is set and the HI08 is in multiplexed bus mode, then HA9/HA2 is
host address line 9 (HA9). If this bit is cleared and the HI08 is in multiplexed
bus mode, then HA9/HA2 is configured as a GPIO signal according to the
value of the HDDR and HDR.
NOTE: HA9EN is ignored when the HI08 is not in the multiplexed bus mode
(that is, when HMUX is cleared).
1
HA8EN
0
Host Address Line 8 Enable
If HA8EN is set and the HI08 is in multiplexed bus mode, then HA8/A1 is
host address line 8 (HA8). If this bit is cleared and the HI08 is in multiplexed
bus mode, then HA8/HA1 is a GPIO signal according to the value of the
HDDR and HDR.
NOTE: HA8EN is ignored when the HI08 is not in the multiplexed bus mode
(that is, when HMUX is cleared).
0
HGEN
0
Host GPIO Port Enable
Enables/disables signals configured as GPIO. If this bit is cleared, signals
configured as GPIO are disconnected: outputs are high impedance, inputs
are electrically disconnected. Signals configured as HI08 are not affected by
the value of HGEN.
DSP56321 Reference Manual, Rev. 1
7-18
Freescale Semiconductor
DSP Core Programming Model
HRW
HDS
In a single-strobe mode, a DS (data strobe) signal qualifies the access, while a R/W (Read-Write)
signal specifies the direction of the access.
Figure 7-7. Single-Strobe Mode
Data
Write Data In
HWR
Write Cycle
Data
Read Data Out
HRD
Read Cycle
In dual-strobe mode, separate HRD and HWR signals specify the access as a read or write
access, respectively.
Figure 7-8. Dual-Strobe Mode
7.6.7 Host Transmit (HTX) Register
The HTX register is used in DSP-to-host data transfers. The DSP56321 views it as a 24-bit
write-only register. Its address is X:$FFFFC7. Writing to the HTX register clears the host transfer
data empty bit (HSR[HTDE]) on the DSP side. The contents of the HTX register are transferred
as 24-bit data to the Receive Data Registers (RXH:RXM:RXL) when both HSR[HTDE] and
receive data full (ISR[RXDF]) on the host-side bits are cleared. This transfer operation sets the
ISR[RXDF] and HSR[HTDE] bits. The DSP56321 can set the HCR[HTIE] bit to cause a host
transmit data interrupt when HSR[HTDE] is set. To prevent the previous data from being
overwritten, the DSP56303 should never write to the HTX when HSR[HTDE] is cleared.
Note:
When data is written to a peripheral device, there is a two-cycle pipeline delay until
any status bits affected by this operation are updated. If you read any of the status bits
within the next two cycles, the bit does not reflect its current status. For details, see
Section 6.4.1, Polling, on page 6-2.
7.6.8 Host Receive (HRX) Register
The HRX register is used in host-to-DSP data transfers. The DSP56321 views it as a 24-bit
read-only register. Its address is X:$FFFFC6. It is loaded with 24-bit data from the transmit data
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-19
Host Interface (HI08)
registers (TXH:TXM:TXL on the host side) when both the transmit data register empty
(ISR[TXDE]) on the host side and host receive data full (HSR[HRDF]) on the DSP side are
cleared. The transfer operation sets both ISR[TXDE] and HSR[HRDF]. When the HSR[HRDF]
is set, the HRX register contains valid data. The DSP56321 can set the HCR[HRIE] to cause a
host receive data interrupt when HSR[HRDF] is set. When the DSP56321 reads the HRX
register, the HSR[HRDF] bit is cleared.
Note:
The DSP56321 should never try to read the HRX register if the HSR[HRDF] bit is
already cleared.
7.6.9 DSP-Side Registers After Reset
Table 7-13 shows the results of the four reset types on the bits in each of the HI08 registers
accessible to the DSP56321. The hardware reset (HW) is caused by the RESET signal. The
software reset (SW) is caused by execution of the RESET instruction. The individual reset (IR)
occurs when HPCR[HEN] is cleared. The stop reset (ST) occurs when the STOP instruction
executes.
Table 7-13. DSP-Side Registers After Reset
Reset Type
Register
Name
Register
Data
HCR
Note:
HW
Reset
SW
Reset
IR
Reset
ST
Reset
All bits
0
0
—
—
HPCR
All bits
0
0
—
—
HSR
HF[1–0]
0
0
—
—
HCP
0
0
0
0
HTDE
1
1
1
1
HRDF
0
0
0
0
HBAR
BA[10–3]
$80
$80
—
—
HDDR
DR[15–0]
0
0
—
—
HDR
D[15–0]
—
—
—
—
HRX
HRX [23–0]
empty
empty
empty
empty
HTX
HTX [23–0]
empty
empty
empty
empty
A long dash (—) denotes that the bit value is not affected by the specified reset.
7.7 Host Programmer Model
The HI08 provides a simple, high-speed interface to a host processor. To the host bus, the HI08
appears to be eight byte-wide registers. Separate transmit and receive data paths are
double-buffered to allow the DSP core and host processor to transfer data efficiently at high
speed. The host can access the HI08 asynchronously using polling techniques or interrupt-based
techniques. The HI08 appears to the host processor as a memory-mapped peripheral occupying
DSP56321 Reference Manual, Rev. 1
7-20
Freescale Semiconductor
Host Programmer Model
eight bytes in the host processor address space. (See Table 7-14.) The eight HI08 registers
include the following:
„
„
„
„
A control register (ICR), on page 7-22
A status register (ISR), on page 7-25
Three data registers (RXH/TXH, RXM/TXM, and RXL/TXL), on page 7-27
Two vector registers (CVR and IVR), on page 7-24 and page 7-27
To transfer data between itself and the HI08, the host processor bus performs the following steps:
1.
Asserts the HI08 address and strobes to select the register to be read or written. (Chip
select in non-multiplexed mode, the address strobe in multiplexed mode.)
2.
Selects the direction of the data transfer. If it is writing, the host processor places the
data on the bus. Otherwise, the HI08 places the data on the bus.
3.
Strobes the data transfer.
Host processors can use standard host processor instructions (for example, byte move) and
addressing modes to communicate with the HI08 registers. The HI08 registers are aligned so that
8-bit host processors can use 8-, 16-, or 24-bit load and store instructions for data transfers. The
HREQ/HTRQ and HACK/HRRQ handshake flags are provided for polled or interrupt-driven
data transfers with the host processor. Because of the speed of the DSP56321 interrupt response,
most host microprocessors can load or store data at their maximum programmed I/O instruction
rate without testing the handshake flags for each transfer. If full handshake is not needed, the host
processor can treat the DSP56321 as a fast device, and data can be transferred between the host
processor and the DSP56321 at the fastest data rate of the host processor.
One of the most innovative features of the host interface is the host command feature. With this
feature, the host processor can issue vectored interrupt requests to the DSP56321. The host can
select any of 128 DSP interrupt routines for execution by writing a vector address register in the
HI08. This flexibility allows the host processor to execute up to 128 pre-programmed functions
inside the DSP56321. For example, the DSP56321 host interrupts allow the host processor to
read or write DSP registers (X, Y, or program memory locations), force interrupt handlers (for
example, ESSI, SCI, IRQA, IRQB interrupt routines), and perform control or debugging
operations.
Note:
When the DSP enters Stop mode, the HI08 signals are electrically disconnected
internally, thus disabling the HI08 until the core leaves stop mode. While the HI08
configuration remains unchanged in Stop mode, the core cannot be restarted via the
HI08 interface. Do not issue a STOP command to the DSP via the HI08 unless you
provide some other mechanism to exit stop mode.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-21
Host Interface (HI08)
Table 7-14. Host-Side Register Map
Host
Address
Big Endian
HLEND = 0
Little Endian
HLEND = 1
Register Name
0
ICR
ICR
Interface Control
1
CVR
CVR
Command Vector
2
ISR
ISR
Interface Status
3
IVR
IVR
Interrupt Vector
4
00000000
00000000
Unused
5
RXH/TXH
RXL/TXL
6
RXM/TXM
RXM/TXM
7
RXL/TXL
RXH/TXH
Receive/Transmit
Data
7.7.1 Interface Control Register (ICR)
The ICR is an 8-bit read/write control register by which the host processor controls the HI08
interrupts and flags. The DSP core cannot access the ICR. The ICR is a read/write register, which
allows the use of bit manipulation instructions on control register bits. Hardware and software
reset clear the ICR bits.
7
INIT
6
5
4
3
HLEN
D
HF1
HF0
2
1
0
HDRQ TREQ RREQ
—Reserved bit; read as 0; write to 0 for future compatibility.
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7-22
Freescale Semiconductor
Host Programmer Model
Table 7-15. Interface Control Register (ICR) Bit Definitions
Bit Number
Bit Name
Reset Value
Description
7
INIT
0
Initialize
The host processor uses the INIT bit to force initialization of the HI08
hardware. During initialization, the HI08 transmit and receive control bits are
configured. Whether it is necessary to use the INIT bit to initialize the HI08
hardware depends on the software design of the interface.
The type of initialization when the INIT bit is set depends on the state of
TREQ and RREQ in the HI08. The INIT command, which is local to the
HI08, configures the HI08 into the desired data transfer mode. When the
host sets the INIT bit, the HI08 hardware executes the INIT command. The
interface hardware clears the INIT bit after the command executes.
6
TREQ
RREQ
After INIT
Execution
Transfer Direction
Initialized
0
0
INIT = 0
None
0
1
INIT = 0;
RXDF = 0; HTDE =
1
DSP to host
1
0
INIT = 0;
TXDE = 1; HRDF =
0
Host to DSP
1
1
INIT = 0;
RXDF = 0; HTDE =
1; TXDE = 1;
HRDF = 0
Host to/from DSP
0
Reserved. Write to 0 for future compatibility.
5
HLEND
0
Host Little Endian
If the HLEND bit is cleared, the host can access the HI08 in Big-Endian byte
order. If set, the host can access the HI08 in Little-Endian byte order. If the
HLEND bit is cleared the RXH/TXH register is located at address $5, the
RXM/TXM register at $6, and the RXL/TXL register at $7. If the HLEND bit is
set, the RXH/TXH register is located at address $7, the RXM/TXM register
at $6, and the RXL/TXL register at $5.
4
HF1
0
Host Flag 1
A general-purpose flag for host-to-DSP communication. The host processor
can set or clear HF1, and the DSP56321 can not change it. HF1 is reflected
in the HSR on the DSP side of the HI08.
3
HF0
0
Host Flag 0
A general-purpose flag for host-to-DSP communication. The host processor
can set or clear HF0, and the DSP56321 cannot change it. HF0 is reflected
in the HSR on the DSP side of the HI08.
2
HDRQ
0
Double Host Request
If cleared, the HDRQ bit configures HREQ/HTRQ and HACK/HRRQ as
HREQ and HACK, respectively. If HDRQ is set, HREQ/HTRQ is configured
as HTRQ, and HACK/HRRQ is configured as HRRQ.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-23
Host Interface (HI08)
Table 7-15. Interface Control Register (ICR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
1
TREQ
0
Transmit Request Enable
Enables host requests via the host request (HREQ or HTRQ) signal when
the transmit data register empty (TXDE) status bit in the ISR is set. If TREQ
is cleared, TXDE interrupts are disabled. If TREQ and TXDE are set, the
host request signal is asserted.
TREQ and RREQ modes (HDRQ = 0)
RREQ
HREQ Signal
TREQ
0
0
No interrupts (polling)
0
1
RXDF request (interrupt)
1
0
TXDE request (interrupt)
1
RXDF and TXDE request (interrupts)
1
TREQ and RREQ modes (HDRQ = 1)
RREQ
HTRQ Signal
HRRQ Signal
TREQ
0
RREQ
0
0
0
No interrupts
(polling)
No interrupts
(polling)
0
1
No interrupts
(polling)
RXDF request
(interrupt)
1
0
TXDE request
(interrupt)
No interrupts
(polling)
1
1
TXDE request
(interrupt)
RXDF request
(interrupt)
Receive Request Enable
Controls the HREQ signal for host receive data transfers. RREQ enables
host requests via the host request (HREQ or HRRQ) signal when the
receive data register full (RXDF) status bit in the ISR is set. If RREQ is
cleared, RXDF interrupts are disabled. If RREQ and RXDF are set, the host
request signal (HREQ or HRRQ) is asserted.
7.7.2 Command Vector Register (CVR)
The host processor uses the CVR, an 8-bit read/write register, to cause the DSP56321 to execute
an interrupt. The host command feature is independent of any of the data transfer mechanisms in
the HI08. It causes execution of any of the 128 possible interrupt routines in the DSP core.
Hardware, software, individual, and stop resets clear the CVR bits.
7
6
5
4
3
2
1
0
HC
HV6
HV5
HV4
HV3
HV2
HV1
HV0
DSP56321 Reference Manual, Rev. 1
7-24
Freescale Semiconductor
Host Programmer Model
Table 7-16. Command Vector Register (CVR) Bit Definitions
Bit Number
Bit Name
Reset Value
Description
7
HC
0
Host Command
The host processor uses the HC bit to handshake the execution of host
command interrupts. Normally, the host processor sets HC to request a host
command interrupt from the DSP56321. When the DSP56321 acknowledges
the host command interrupt, HI08 hardware clears the HC bit. The host
processor can read the state of HC to determine when the host command has
been accepted. After setting HC, the host must not write to the CVR again
until the HI08 hardware clears the HC. Setting the HC bit causes host
command pending (HCP) to be set in the HSR. The host can write to the HC
and HV bits in the same write cycle.
6–0
HV[6–0]
$32
Host Vector
Select the host command interrupt address for use by the host command
interrupt logic. When the DSP interrupt control logic recognizes the host
command interrupt, the address of the interrupt routine taken is 2 × HV. The
host can write HC and HV in the same write cycle.
The host processor can select any of the 128 possible interrupt routine
starting addresses in the DSP by writing the interrupt routine address divided
by 2 into the HV bits. This means that the host processor can force any
interrupt handler (ESSI, SCI, IRQA, IRQB, and so forth) and can use any
reserved or otherwise unused addresses (if have been pre-programmed in the
DSP). HV is set to $32 (vector location $064) by hardware, software,
individual, and stop resets.
7.7.3 Interface Status Register (ISR)
The host processor uses the ISR, an 8-bit read-only status register, to interrogate the HI08 status
and flags. The DSP core cannot address the ISR.
7
HREQ
6
5
4
3
2
1
0
HF3
HF2
TRDY
TXDE
RXDF
—Reserved bit; read as 0; write to 0 for future compatibility.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-25
Host Interface (HI08)
Table 7-17. Interface Status Register (ISR) Bit Definitions
Bit Number
Bit Name
Reset Value
Description
7
HREQ
0 (Hardware
and Software
reset)
1 (Individual
reset and
TREQ is set)
1 (Stop reset
and TREQ is
set)
Host Request
If HDRQ is set, the HREQ bit indicates the status of the external transmit and
receive request output signals (HTRQ and HRRQ). If HDRQ is cleared,
HREQ indicates the status of the external host request output signal
(HREQ). The HREQ bit is set from either or both of two conditions— the
receive byte registers are full or the transmit byte registers are empty. These
conditions are indicated by status bits: ISR RXDF indicates that the receive
byte registers are full, and ISR TXDE indicates that the transmit byte
registers are empty. If the interrupt source is enabled by the associated
request enable bit in the ICR, HREQ is set if one or more of the two enabled
interrupt sources is set.
6–5
HDRQ
HREQ
0
0
0
1
1
0
1
1
Effect
HREQ is cleared; no host processor
interrupts are requested.
HREQ is set; an interrupt is requested.
HTRQ and HRRQ are cleared, no host
processor interrupts are requested.
HTRQ or HRRQ are set; an interrupt is
requested.
0
Reserved. Write to 0 for future compatibility.
4
HF3
0
Host Flag 3
Indicates the state of HF3 in the HCR on the DSP side. HF3 can be changed
only by the DSP56321. Hardware and software reset clear HF3.
3
HF2
0
Host Flag 2
Indicates the state of HF2 in the HCR on the DSP side. HF2 can be changed
only by the DSP56321. Hardware and software reset clear HF2.
2
TRDY
1
Transmitter Ready
Indicates that TXH:TXM:TXL and the HRX registers are empty. If TRDY is
set, the data that the host processor writes to TXH:TXM:TXL is immediately
transferred to the DSP side of the HI08. This feature has many applications.
For example, if the host processor issues a host command that causes the
DSP56321 to read the HRX, the host processor can be guaranteed that the
data it just transferred to the HI08 is that being received by the DSP56321.
Hardware, software, individual, and stop resets all set TRDY.
CAUTION:
TRDY = TXDE and HRDF
1
TXDE
1
Transmit Data Register Empty
Indicates that the transmit byte registers (TXH:TXM:TXL) are empty and can
be written by the host processor. TXDE is set when the contents of the
transmit byte registers are transferred to the HRX register. TXDE is cleared
when the transmit register (TXL or TXH according to HLEND bit) is written by
the host processor. The host processor can set TXDE using the initialize
function. TXDE can assert the external HTRQ signal if the TREQ bit is set.
Regardless of whether the TXDE interrupt is enabled, TXDE indicates
whether the TX registers are full and data can be latched in (so that polling
techniques may be used by the host processor). Hardware, software,
individual, and stop resets all set TXDE.
DSP56321 Reference Manual, Rev. 1
7-26
Freescale Semiconductor
Host Programmer Model
Table 7-17. Interface Status Register (ISR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
0
RXDF
0
Receive Data Register Full
Indicates that the receive byte registers (RXH:RXM:RXL) contain data from
the DSP56321 to be read by the host processor. RXDF is set when the HTX
is transferred to the receive byte registers. RXDF is cleared when the host
processor reads the receive data register (RXL or RXH according to HLEND
bit). The host processor can clear RXDF using the initialize function. RXDF
can assert the external HREQ signal if the RREQ bit is set. Regardless of
whether the RXDF interrupt is enabled, RXDF indicates whether the RX
registers are full and data can be latched out (so that the host processor can
use polling techniques).
7.7.4 Interrupt Vector Register (IVR)
The IVR is an 8-bit read/write register that typically contains the interrupt vector number used
with MC68000 family processor vectored interrupts. Only the host processor can read and write
this register. The contents of the IVR are placed on the host data bus, H[7–0], when both the
HREQ and HACK signals are asserted. The contents of this register are initialized to $0F by a
hardware or software reset. This value corresponds to the uninitialized interrupt vector in the
MC68000 family.
7
6
5
4
3
2
1
0
IV7
IV6
IV5
IV4
IV3
IV2
IV1
IV0
7.7.5 Receive Data Registers (RXH:RXM:RXL)
The host processor views the receive byte registers as three 8-bit read-only registers: the receive
high register (RXH), the receive middle register (RXM), and the receive low register (RXL).
They receive data from the high, middle, and low bytes, respectively, of the HTX register and are
selected by the external host address inputs (HA[2–0]) during a host processor read operation.
The memory address of the receive byte registers are set by ICR[HLEND]. If ICR[HLEND] is
set, the RXH is located at address $7, RXM at $6, and RXL at $5. If ICR[HLEND] is cleared, the
RXH is located at address $5, RXM at $6, and RXL at $7.
When data is transferred from the HTX register to the receive byte register at host address $7, the
ISR Receive Data Register Full (RXDF) bit is set. The host processor can program the RREQ bit
to assert the external HREQ signal when ISR[RXDF] is set. This indicates that the HI08 has a full
word (either 8, 16, or 24 bits) for the host processor. The host processor can program the RREQ
bit to assert the external HREQ signal when ISR[RXDF] is set. Assertion of the HREQ signal
informs the host processor that the receive byte registers have data to be read. When the host
reads the receive byte register at host address $7, the ISR[RXDF] bit is cleared.
Note:
The external host should never read the RXH:RXM:RXL registers if the ISR[RXDF]
bit is cleared.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-27
Host Interface (HI08)
7.7.6 Transmit Data Registers (TXH:TXM:TXL)
The host processor views the transmit byte registers as three 8-bit write-only registers. These
registers are the transmit high register (TXH), the transmit middle register (TXM), and the
transmit low register (TXL). These registers send data to the high, middle, and low bytes,
respectively, of the HRX register and are selected by the external host address inputs, HA[2–0],
during a host processor write operation.
If ICR[HLEND] is set, the TXH register is located at address $7, the TXM register at $6, and the
TXL register at $5. If the HLEND bit in the ICR is cleared, the TXH register is located at address
$5, the TXM register at $6, and the TXL register at $7. The external host should never write to
the TXH:TXM:TXL registers if the ISR[TXDE] bit is cleared.
Data can be written into the transmit byte registers when the ISR transmit data register empty
(TXDE) bit is set. The host processor can program the ICR[TREQ] bit to assert the external
HREQ/HTRQ signal when ISR[TXDE] is set. This informs the host processor that the transmit
byte registers are empty. Writing to the data register at host address $7 clears the ISR[TXDE] bit.
The contents of the transmit byte registers are transferred as 24-bit data to the HRX register when
both ISR[TXDE] and HSR[HRDF] are cleared. This transfer operation sets HSR[TXDE] and
HSR[HRDF].
Note:
When data is written to a peripheral device, there is a two-cycle pipeline delay until
any status bits affected by this operation are updated. If you read any of those status
bits within the next two cycles, the bit will not reflect its current status. For details, see
Section 6.4.1, Polling, on page 6-2.
7.7.7 Host-Side Registers After Reset
Table 7-18 shows the result of the four kinds of reset on bits in each of the HI08 registers seen by
the host processor. To cause a hardware reset, assert the RESET signal. To cause a software reset,
execute the RESET instruction. To reset the HEN bit individually, clear the HPCR[HEN] bit. To
cause a stop reset, execute the STOP instruction.
Table 7-18. Host-Side Registers After Reset
Reset Type
Register
Name
Register
Data
ICR
CVR
HW
Reset
SW
Reset
Individual Reset
STOP
All bits
0
0
—
—
HC
0
0
0
0
HV[0–6]
$32
$32
—
—
DSP56321 Reference Manual, Rev. 1
7-28
Freescale Semiconductor
Programming Model Quick Reference
Table 7-18. Host-Side Registers After Reset (Continued)
Reset Type
Register
Name
Register
Data
ISR
HW
Reset
SW
Reset
HREQ
0
HF3 -HF2
Individual Reset
STOP
0
1 if TREQ is set;
0 otherwise
1 if TREQ is set;
0 otherwise
0
0
—
—
TRDY
1
1
1
1
TXDE
1
1
1
1
RXDF
0
0
0
0
IVR
IV[0–7]
$0F
$0F
—
—
RX
RXH:RXM:RXL
empty
empty
empty
empty
TX
TXH:TXM:TXL
empty
empty
empty
empty
Note:
A long dash (—) denotes that the bit value is not affected by the specified reset.
7.8 Programming Model Quick Reference
Table 7-19 summarizes the HI08 programming model.
Table 7-19. HI08 Programming Model, DSP Side
Bit
Register
HCR
Reset Type
Bit
No.
Bit
Name
Value
HW/
SW
Individual
STOP
0
HRIE
Receive Interrupt
Enable
0
1
HRRQ interrupt disabled
HRRQ interrupt enabled
0
—
—
1
HTIE
Transmit
Interrupt Enable
0
1
HTRQ interrupt disabled
HTRQ interrupt enabled
0
—
—
2
HCIE
Host Command
Interrupt Enable
0
1
HCP interrupt disabled
HCP interrupt enabled
0
—
—
3
HF2
Host Flag 2
0
4
HF3
Host Flag 3
0
—
—
Function
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-29
Host Interface (HI08)
Table 7-19. HI08 Programming Model, DSP Side (Continued)
Bit
Register
HPCR
HW/
SW
Individual
STOP
GPIO signal disconnected
GPIO signals active
0
—
—
0
1
HA8/A1 = GPIO
HA8/A1 = HA8
0
—
—
Host Address
Line 9 Enable
0
1
HA9/A2 = GPIO
HA9/A2 = HA9
0
—
—
Host Chip Select
Enable
0
1
HCS/A10 = GPIO
HCS/A10 = HCS
0
—
—
HDRQ = 0
HDRQ = 1
HREQ/HTRQ = GPIO
HREQ/HTRQ
HACK/HRRQ = GPIO
HREQ/HTRQ =
HREQ,HREQ/HTRQ
HACK/HRRQ = HTRQ, HRRQ
0
—
—
HDRQ = 0
HDRQ=1
HACK/HRRQ
HREQ/HTRQ
HACK/HRRQ
HACK/HRRQ
HREQ/HTRQ
HACK/HRRQ
0
—
—
Bit
No.
Bit
0
HGEN
Host GPIO
Enable
0
1
1
HA8EN
Host Address
Line 8 Enable
2
HA9EN
3
HCSEN
4
HREN
Name
Value
Host Request
Enable
0
1
5
HAEN
Host
Acknowledge
Enable
0
1
HPCR
6
HEN
7
—
8
Reset Type
Function
= GPIO
= GPIO
= HACK
= HTRQ, HRRQ
Host Enable
0
1
Host Port = GPIO
Host Port Active
0
—
—
Reserved
0
Reserved
0
—
—
HROD
Host Request
Open Drain
0
1
HREQ/HTRQ/HRRQ = driven
HREQ/HTRQ/HRRQ = open drain
0
9
HDSP
Host Data Strobe
Polarity
0
1
HDS/HRD/HWR active low
HDS/HRD/HWR active high
0
—
—
10
HASP
Host Address
Strobe Polarity
0
1
HAS active low
HAS active high
0
—
—
11
HMUX
Host Multiplexed
Bus
0
1
Separate address and data lines
Multiplexed address/data
0
—
—
12
HDDS
Host Dual Data
Strobe
0
1
Single Data Strobe (HDS)
Double Data Strobe (HWR, HRD)
0
—
—
13
HCSP
Host Chip Select
Polarity
0
1
HCS active low
HCS active high
0
—
—
14
HRP
Host Request
Polarity
0
1
HREQ/HTRQ/HRRQ active low
HREQ/HTRQ/HRRQ active high
0
—
—
15
HAP
Host
Acknowledge
Polarity
0
1
HACK active low
HACK active high
0
—
—
DSP56321 Reference Manual, Rev. 1
7-30
Freescale Semiconductor
Programming Model Quick Reference
Table 7-19. HI08 Programming Model, DSP Side (Continued)
Bit
Register
HSR
Bit
No.
Bit
0
HRDF
Host Receive
Data Full
0
1
1
HTDE
Host Transmit
Data Empty
1
Name
Reset Type
HW/
SW
Individual
STOP
No receive data to be read
Receive Data Register is full
0
0
0
The Transmit Data Register is
empty.
The Transmit Data Register is not
empty.
1
1
1
No host command pending
Host command pending
0
0
0
Value
0
0
1
Function
2
HCP
Host Command
Pending
3
HF0
Host Flag 0
0
—
—
4
HF1
Host Flag 1
0
—
—
HBAR
7–0
BA[10–
3]
HRX
23–
0
DSP Receive
Data Register
empty
HTX
23–
0
DSP Transmit
Data Register
empty
HDR
16–
0
D[16–0]
GPIO signal Data
$0000
—
—
HDRR
16–
0
DR[16–
0]
GPIO signal
Direction
$0000
—
—
Host Base
Address Register
$80
0
1
Input
Output
Table 7-20. HI08 Programming Model: Host Side
Bit
Registe
r
ICR
Reset Type
HW/
SW
Indi
vi-d
ual
STO
P
HRRQ interrupt disabled
HRRQ interrupt enabled
0
—
—
0
1
HTRQ interrupt disabled
HTRQ interrupt enabled
0
—
—
0
HREQ/HTRQ =
HACK/HRRQ =
HREQ/HTRQ =
HACK/HRRQ =
0
—
—
Bit
No.
Bit
0
RREQ
Receive Request Enable
0
1
1
TREQ
Transmit Request Enable
2
HDRQ
Double Host Request
Name
Valu
e
1
Function
HREQ,
HACK
HTRQ,
HRRQ
3
HF0
Host Flag 0
0
—
—
4
HF1
Host Flag 1
0
—
—
5
HLEND
7
INIT
Host Little Endian
0
1
Big Endian order
Little Endian order
0
—
—
Initialize
1
Reset data paths according to
TREQ and RREQ
0
—
—
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
7-31
Host Interface (HI08)
Table 7-20. HI08 Programming Model: Host Side (Continued)
Bit
Registe
r
Reset Type
HW/
SW
Indi
vi-d
ual
STO
P
Host Receive Register is empty
Host Receive Register is full
0
0
0
1
0
Host Transmit Register is empty
Host Transmit Register is full
1
1
1
1
0
transmit FIFO (6 deep) is empty
transmit FIFO is not empty
1
1
1
Host Flag 2
0
—
—
Host Flag 3
0
—
—
0
0
0
$32
—
—
0
0
0
—
—
Valu
e
Function
Receive Data Register Full
0
1
TXDE
Transmit Data Register
Empty
2
TRDY
Transmitter Ready
3
HF2
4
HF3
7
HREQ
CVR
6–0
HV[6–0]
CVR
7
HC
RXH/M/
L
7–0
Host Receive Data Register
empt
y
TXH/M/L
7–0
Host Transmit Data Register
empt
y
IVR
7–0
ISR
Bit
No.
Bit
0
RXDF
1
IV[7–0]
Name
Host Request
0
1
HREQ signal is deasserted
HREQ signal is asserted (if
enabled)
Host Command Vector
Host Command
Interrupt Register
0
1
no host command pending
host command pending
68000 family vector register
$0F
DSP56321 Reference Manual, Rev. 1
7-32
Freescale Semiconductor
Enhanced Synchronous Serial Interface
8
The enhanced synchronous serial interface (ESSI) provides a full-duplex serial port for serial
communication with a variety of serial devices, including one or more industry-standard codecs,
other DSPs, microprocessors, and peripherals. The ESSI consists of independent transmitter and
receiver sections and a common ESSI clock generator. There are two independent and identical
ESSIs in the DSP56321: ESSI0 and ESSI1. For simplicity, a single generic ESSI is described
here. The ESSI block diagram is shown in Figure 8-1. This interface is synchronous because all
serial transfers are synchronized to one clock.
GDB
DDB
RCLK
RSMA
RSMB
TSMA
TSMB
RX SHIFT REG
SRD
RX
TCLK
TX0 SHIFT REG
STD
TX0
CRA
TX1 SHIFT REG
CRB
SC0
TX1
TSR
TX2 SHIFT
SSISR
SC1
TX2
Interrupts
Clock/Frame Sync Generators and Control Logic
SC2
SCK
Figure 8-1. ESSI Block Diagram
Note:
This synchronous interface should not be confused with the asynchronous channels
mode of the ESSI, in which separate clocks are used for the receiver and transmitter. In
that mode, the ESSI is still a synchronous device because all transfers are synchronized
to these clocks. Pin notations for the generic ESSI refer to the analogous pin of ESSI0
(PCx) and ESSI1 (PDx).
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-1
Enhanced Synchronous Serial Interface
Additional synchronization signals delineate the word frames. The Normal mode of operation
transfers data at a periodic rate, one word per period. The Network mode is similar in that it is
also for periodic transfers; however, it supports up to 32 words (time slots) per period. The
Network mode can be used to build time division multiplexed (TDM) networks. In contrast, the
On-Demand mode is for nonperiodic transfers of data. This mode, which offers a subset of the
Serial Peripheral Interface (SPI) protocol, can transfer data serially at high speed when the data
become available. Since each ESSI unit can be configured with one receiver and three
transmitters, the two units can be used together for surround sound applications (which need two
digital input channels and six digital output channels).
8.1 ESSI Data and Control Signals
Three to six signals are required for ESSI operation, depending on the operating mode selected.
The serial transmit data (STD) signal and serial control (SC0 and SC1) signals are fully
synchronized to the clock if they are programmed as transmit-data signals.
8.1.1 Serial Transmit Data Signal (STD)
The STD signal transmits data from the serial transmit shift register. STD is an output when data is
transmitted from the TX0 shift register. With an internally-generated bit clock, the STD signal
becomes a high impedance output signal for a full clock period after the last data bit is
transmitted if another data word does not follow immediately. If sequential data words are
transmitted, the STD signal does not assume a high-impedance state. The STD signal can be
programmed as a GPIO signal (P5) when the ESSI STD function is not in use.
8.1.2 Serial Receive Data Signal (SRD)
SRD receives
serial data and transfers the data to the receive shift register. SRD can be
programmed as a GPIO signal (P4) when the SRD function is not in use.
8.1.3 Serial Clock (SCK)
is a bidirectional signal providing the serial bit rate clock for the ESSI interface. The signal is
a clock input or output used by all the enabled transmitters and receivers in Synchronous modes
or by all the enabled transmitters in Asynchronous modes. See Table 8-1 for details. SCK can be
programmed as a GPIO signal (P3) when not used as the ESSI clock.
SCK
DSP56321 Reference Manual, Rev. 1
8-2
Freescale Semiconductor
ESSI Data and Control Signals
Table 8-1. ESSI Clock Sources
SYN
SCKD
SCD0
RX Clock Source
RX Clock
Out
TX Clock Source
TX Clock Out
Asynchronous
0
0
0
EXT, SC0
—
EXT, SCK
—
0
0
1
INT
SC0
EXT, SCK
—
0
1
0
EXT, SC0
—
INT
SCK
0
1
1
INT
SC0
INT
SCK
Synchronous
1
0
0/1
EXT, SCK
—
EXT, SCK
—
1
1
0/1
INT
SCK
INT
SCK
Note:
Although an external serial clock can be independent of and asynchronous to the DSP
system clock, the external ESSI clock frequency must not exceed Fcore/3, and each
ESSI phase must exceed the minimum of 1.5 CLKOUT cycles. The internally sourced
ESSI clock frequency must not exceed Fcore/4.
8.1.4 Serial Control Signal (SC0)
ESSI0: SC00; ESSI1: SC10
To determine the function of the SC0 signal, select either Synchronous or Asynchronous mode,
according to Table 8-2. In Asynchronous mode, this signal is used for the receive clock I/O. In
Synchronous mode, this signal is the transmitter data out signal for transmit shift register TX1 or
for serial flag I/O. A typical application of serial flag I/O would be multiple device selection for
addressing in codec systems.
If SC0 is configured as a serial flag signal or receive clock signal, its direction is determined by
the Serial Control Direction 0 (SCD0) bit in ESSI Control Register B (CRB). When configured as
an output, SC0 functions as the serial Output Flag 0 (OF0) or as a receive shift register clock
output. If SC0 is used as the serial Output Flag 0, its value is determined by the value of the serial
Output Flag 0 (OF0) bit in the CRB. If SC0 is an input, it functions as either serial Input Flag 0 or
a receive shift register clock input. As serial Input Flag 0, SC0 controls the state of the serial Input
Flag 0 (IF0) bit in the ESSI Status Register (SSISR).
When SC0 is configured as a transmit data signal, it is always an output signal, regardless of the
SCD0 bit value. SC0 is fully synchronized with the other transmit data signals (STD and SC1). SC0
can be programmed as a GPIO signal (P0) when the ESSI SC0 function is not in use.
Note:
The ESSI can operate with more than one active transmitter only in Synchronous
mode.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-3
Enhanced Synchronous Serial Interface
8.1.5 Serial Control Signal (SC1)
ESSI0:SC01; ESSI1: SCI11
To determine the function of SC1, select either Synchronous or Asynchronous mode, according to
Table 8-2. In Asynchronous mode (as for a single codec with asynchronous transmit and
receive), SC1 is the receiver frame sync I/O. In Synchronous mode, SC1 is the transmitter data out
signal of transmit shift register TX2, for the transmitter 0 drive-enabled signal, or for serial flag
I/O. As serial flag I/O, SC1 operates like SC0. SC0 and SC1are independent flags but can be used
together for multiple serial device selection; they can be unencoded to select up to two CODECs
or decoded externally to select up to four CODECs. If SC1 is configured as a serial flag or receive
frame sync signal, the Serial Control Direction 1 CRB[SCD1] bit determines its direction.
Table 8-2. Mode and Signal Definitions
Control Bits
ESSI Signals
SYN
TE0
TE1
TE2
RE
SC0
SC1
SC2
SCK
STD
SRD
0
0
X
X
0
U
U
U
U
U
U
0
0
X
X
1
RXC
FSR
U
U
U
RD
0
1
X
X
0
U
U
FST
TXC
TD0
U
0
1
X
X
1
RXC
FSR
FST
TXC
TD0
RD
1
0
0
0
0
U
U
U
U
U
U
1
0
0
0
1
F0/U
F1/T0D/U
FS
XC
U
RD
1
0
0
1
0
F0/U
TD2
FS
XC
U
U
1
0
0
1
1
F0/U
TD2
FS
XC
U
RD
1
0
1
0
0
TD1
F1/T0D/U
FS
XC
U
U
1
0
1
0
1
TD1
F1/T0D/U
FS
XC
U
RD
1
0
1
1
0
TD1
TD2
FS
XC
U
U
1
0
1
1
1
TD1
TD2
FS
XC
U
RD
1
1
0
0
0
F0/U
F1/T0D/U
FS
XC
TD0
U
1
1
0
0
1
F0/U
F1/T0D/U
FS
XC
TD0
RD
1
1
0
1
0
F0/U
TD2
FS
XC
TD0
U
1
1
0
1
1
F0/U
TD2
FS
XC
TD0
RD
1
1
1
0
0
TD1
F1/T0D/U
FS
XC
TD0
U
1
1
1
0
1
TD1
F1/T0D/U
FS
XC
TD0
RD
1
1
1
1
0
TD1
TD2
FS
XC
TD0
U
DSP56321 Reference Manual, Rev. 1
8-4
Freescale Semiconductor
Operation
Table 8-2. Mode and Signal Definitions (Continued)
Control Bits
ESSI Signals
SYN
TE0
TE1
TE2
RE
SC0
SC1
SC2
SCK
STD
SRD
1
1
1
1
1
TD1
TD2
FS
XC
TD0
RD
TXC
RXC
XC
FST
FSR
FS
TD0
TD1
TD2
T0D
RD
F0
F1
U
X
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
Transmitter clock
Receiver clock
Transmitter/receiver clock (synchronous operation)
Transmitter frame sync
Receiver frame sync
Transmitter/receiver frame sync (synchronous operation)
Transmit data signal 0
Transmit data signal 1
Transmit data signal 2
Transmitter 0 drive enable if SSC1 = 1 & SCD1 = 1
Receive data
Flag 0
Flag 1 if SSC1 = 0
Unused (can be used as GPIO signal)
Indeterminate
When configured as an output, SC1 functions as a serial Output Flag, as the transmitter 0
drive-enabled signal, or as the receive frame sync signal output. If SC1 is used as serial Output
Flag 1, its value is determined by the value of the serial Output Flag 1 (OF1) bit in the CRB.
When configured as an input, this signal can receive frame sync signals from an external source,
or it acts as a serial input flag. As a serial input flag, SC1controls status bit IF1 in the SSISR.
When SC1 is configured as a transmit data signal, it is always an output signal, regardless of the
SCD1 bit value. As an output, it is fully synchronized with the other ESSI transmit data signals
(STD and SC0). SC1 can be programmed as a GPIO signal (P1) when the ESSI SC1 function is not
in use.
8.1.6 Serial Control Signal (SC2)
ESSI0:SC02; ESSI1:SC12
is a frame sync I/O signal for both the transmitter and receiver in Synchronous mode and for
the transmitter only in Asynchronous mode. The direction of this signal is determined by the
SCD2 bit in the CRB. When configured as an output, this signal outputs the internally generated
frame sync signal. When configured as an input, this signal receives an external frame sync signal
for the transmitter in Asynchronous mode and for both the transmitter and receiver when in
Synchronous mode. SC2 can be programmed as a GPIO signal (P2) when the ESSI SC2 function is
not in use.
SC2
8.2 Operation
This section discusses ESSI basics: reset state, initialization, and exceptions.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-5
Enhanced Synchronous Serial Interface
8.2.1 ESSI After Reset
A hardware RESET signal or software RESET instruction clears the port control register and the
port direction control register, thus configuring all the ESSI signals as GPIO. The ESSI is in the
reset state while all ESSI signals are programmed as GPIO; it is active only if at least one of the
ESSI I/O signals is programmed as an ESSI signal.
8.2.2 Initialization
To initialize the ESSI, do the following:
1.
Send a reset: hardware RESET signal, software RESET instruction, ESSI individual
reset, or STOP instruction reset.
2.
Program the ESSI control and time slot registers.
3.
Write data to all the enabled transmitters.
4.
Configure at least one signal as ESSI signal.
5.
If an external frame sync is used, from the moment the ESSI is activated, at least five (5)
serial clocks are needed before the first external frame sync is supplied. Otherwise,
improper operation may result.
When the PC[5–0] bits in the GPIO Port Control Register (PCR) are cleared during program
execution, the ESSI stops serial activity and enters the individual reset state. All status bits of the
interface are set to their reset state. The contents of CRA and CRB are not affected. The ESSI
individual reset allows a program to reset each interface separately from the other internal
peripherals. During ESSI individual reset, internal DMA accesses to the data registers of the
ESSI are not valid, and data read there are undefined. To ensure proper operation of the ESSI, use
an ESSI individual reset when you change the ESSI control registers (except for bits TEIE, REIE,
TLIE, RLIE, TIE, RIE, TE2, TE1, TE0, and RE). Here is an example of how to initialize the
ESSI.
1.
Put the ESSI in its individual reset state by clearing the PCR bits.
2.
Configure the control registers (CRA, CRB) to set the operating mode. Disable the
transmitters and receiver by clearing the TE[2–0] and RE bits. Set the interrupt enable
bits for the operating mode chosen.
3.
Enable the ESSI by setting the PCR bits to activate the input/output signals to be used.
4.
Write initial data to the transmitters that are in use during operation. This step is needed
even if DMA services the transmitters.
5.
Enable the transmitters and receiver to be used.
DSP56321 Reference Manual, Rev. 1
8-6
Freescale Semiconductor
Operation
Now the ESSI can be serviced by polling, interrupts, or DMA. Once the ESSI is enabled (Step 3),
operation starts as follows:
1.
For internally generated clock and frame sync, these signals start activity immediately
after the ESSI is enabled.
2.
The ESSI receives data after a frame sync signal (either internally or externally
generated) only when the receive enable (RE) bit is set.
3.
Data is transmitted after a frame sync signal (either internally or externally generated)
only when the transmitter enable (TE[2–0]) bit is set.
8.2.3 Exceptions
The ESSI can generate six different exceptions. They are discussed in the following paragraphs
(ordered from the highest to the lowest exception priority):
„
„
„
„
„
ESSI receive data with exception status:
Occurs when the receive exception interrupt is enabled, the receive data register is full,
and a receiver overrun error has occurred. This exception sets the ROE bit. The ROE bit is
cleared when you first read the SSISR and then read the Receive Data Register (RX).
ESSI receive data:
Occurs when the receive interrupt is enabled, the receive data register is full, and no
receive error conditions exist. A read of RX clears the pending interrupt. This error-free
interrupt can use a fast interrupt service routine for minimum overhead.
ESSI receive last slot interrupt:
Occurs when the ESSI is in Network mode and the last slot of the frame has ended. This
interrupt is generated regardless of the receive mask register setting. The receive last slot
interrupt can signal that the receive mask slot register can be reset, the DMA channels can
be reconfigured, and data memory pointers can be reassigned. Using the receive last slot
interrupt guarantees that the previous frame is serviced with the previous setting and the
new frame is serviced with the new setting without synchronization problems.
The maximum time it takes to service a receive last slot interrupt should not exceed N – 1
ESSI bits service time (where N is the number of bits the ESSI can transmit per time slot).
ESSI transmit data with exception status:
Occurs when the transmit exception interrupt is enabled, at least one transmit data register
of the enabled transmitters is empty, and a transmitter underrun error has occurred. This
exception sets the SSISR[TUE] bit. The TUE bit is cleared when you first read the SSISR
and then write to all the transmit data registers of the enabled transmitters, or when you
write to TSR to clear the pending interrupt.
ESSI transmit last slot interrupt:
Occurs when the ESSI is in Network mode at the start of the last slot of the frame. This
exception occurs regardless of the transmit mask register setting. The transmit last slot
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-7
Enhanced Synchronous Serial Interface
interrupt can signal that the transmit mask slot register can be reset, the DMA channels
can be reconfigured, and data memory pointers can be reassigned. Using the Transmit Last
Slot interrupt guarantees that the previous frame is serviced with the previous frame
settings and the new frame is serviced with the new frame settings without
synchronization problems.
Note:
„
The maximum transmit last slot interrupt service time should not exceed
N – 1 ESSI bits service time (where N is the number of bits in a slot).
ESSI transmit data:
Occurs when the transmit interrupt is enabled, at least one of the enabled transmit data
registers is empty, and no transmitter error conditions exist. Write to all the enabled TX
registers or to the TSR to clear this interrupt. This error-free interrupt uses a fast interrupt
service routine for minimum overhead (if no more than two transmitters are used).
To configure an ESSI exception, perform the following steps:
1.
Configure the interrupt service routine (ISR):
a.
Load vector base address register
VBA (b23:8)
b.
2.
Define I_VEC to be equal to the VBA value (if that is nonzero). If it is defined,
I_VEC must be defined for the assembler before the interrupt equate file is
included.
c. Load the exception vector table entry: two-word fast interrupt, or jump/branch to
subroutine (long interrupt).
p:I_SI0TD
Configure interrupt trigger; preload transmit data
a.
Enable and prioritize overall peripheral interrupt functionality.
IPRP (S0L1:0)
b.
c.
d.
e.
f.
Write data to all enabled transmit registers.
TX00
Enable a peripheral interrupt-generating function.CRB (TE0)
Enable a specific peripheral interrupt.
CRB0 (TIE)
Enable peripheral and associated signals.
PCRC (PC[5–0])
Unmask interrupts at the global level.
SR (I1–0)
The example material to the right of the steps shows register settings for configuring an ESSI0
transmit interrupt using transmitter 0. The order of the steps is optional except that the interrupt
trigger configuration must not be completed until the ISR configuration is complete. Since step
2c may cause an immediate transmit without generating an interrupt, perform the transmit data
preload in step 2b before step 2c to ensure that valid data is sent in the first transmission. After
the first transmit, subsequent transmit values are typically loaded into TXnn by the ISR (one
value per register per interrupt). Therefore, if N items are to be sent from a particular TXnn, the
ISR needs to load the transmit register (N – 1) times. Steps 2c and 2d can be performed in step
DSP56321 Reference Manual, Rev. 1
8-8
Freescale Semiconductor
Operating Modes: Normal, Network, and On-Demand
2a as a single instruction. If an interrupt trigger event occurs before all interrupt trigger
configuration steps are performed, the event is ignored and not queued. If interrupts derived from
the core or other peripherals need to be enabled at the same time as ESSI interrupts, step 2f
should be performed last.
8.3 Operating Modes: Normal, Network, and On-Demand
The ESSI has three basic operating modes and several data and operation formats. These modes
are programmed via the ESSI control registers. The data and operation formats available to the
ESSI are selected when you set or clear control bits in the CRA and CRB. These control bits are
WL[2–1], MOD, SYN, FSL[1–0], FSR, FSP, CKP, and SHFD.
8.3.1 Normal/Network/On-Demand Mode Selection
To select either Normal mode or Network mode, clear or set CRB[MOD]. In Normal mode, the
ESSI sends or receives one data word per frame (per enabled receiver or transmitter). In Network
mode, 2 to 32 time slots per frame can be selected. During each frame, 0 to 32 data words are
received or transmitted (from each enabled receiver or transmitter). In either case, the transfers
are periodic. The Normal mode typically transfers data to or from a single device. Network mode
is typically used in time division multiplexed networks of CODECs or DSPs with multiple words
per frame.
Network mode has a submode called On-Demand mode. Set the CRB[MOD] for Network mode,
and set the frame rate divider to 0 (DC = $00000) to select On-Demand mode. This submode
does not generate a periodic frame sync. A frame sync pulse is generated only when data is
available to transmit. The frame sync signal indicates the first time slot in the frame. On-Demand
mode requires that the transmit frame sync be internal (output) and the receive frame sync be
external (input). For simplex operation, Synchronous mode could be used; however, for
full-duplex operation, Asynchronous mode must be used. You can enable data transmission that
is data-driven by writing data into each TX. Although the ESSI is double-buffered, only one
word can be written to each TX, even if the transmit shift register is empty. The receive and
transmit interrupts function normally, using TDE and RDF; however, transmit underruns are
impossible for On-Demand transmission and are disabled. This mode is useful for interfacing
with codecs requiring a continuous clock.
Note:
When the ESSI transmits data in On-Demand mode (that is, MOD = 1 in the CRB and
DC[4–0]=$00000 in the CRA) with WL[2–0] = 100, the transmission does not work
properly. To ensure correct operation, do not use On-Demand mode with the WL[2–0]
= 100 32-bit word length mode.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-9
Enhanced Synchronous Serial Interface
8.3.2 Synchronous/Asynchronous Operating Modes
The transmit and receive sections of the ESSI interface are synchronous or asynchronous. The
transmitter and receiver use common clock and synchronization signals in Synchronous mode
and separate clock and sync signals in Asynchronous mode. The CRB[SYN] bit selects
synchronous or asynchronous operation. When the SYN bit is cleared, the ESSI TX and RX
clocks and frame sync sources are independent. If the SYN bit is set, the ESSI TX and RX clocks
and frame sync are driven by the same source (either external or internal). Separate receive and
transmit interrupts are provided. Transmitter 1 and transmitter 2 operate only in Synchronous
mode. Data clock and frame sync signals are generated internally by the DSP or obtained from
external sources. If clocks are internally generated, the ESSI clock generator derives bit clock and
frame sync signals from the DSP internal system clock. The ESSI clock generator consists of a
selectable fixed prescaler with a programmable prescaler for bit rate clock generation and a
programmable frame-rate divider with a word-length divider for frame-rate sync-signal
generation.
8.3.3 Frame Sync Selection
The transmitter and receiver can operate independently. The transmitter can have either a bit-long
or word-long frame-sync signal format, and the receiver can have the same or another format.
The selection is made by programming the CRB FSL[1–0], FSR, and FSP bits.
8.3.4 Frame Sync Signal Format
CRB[FSL1] controls the frame sync signal format:
„
„
If CRB[FSL1] is cleared, the receive frame sync is asserted during the entire data transfer
period. This frame sync length is compatible with codecs, serial peripherals that conform
to the Freescale SPI, serial A/D and D/A converters, shift registers, and
telecommunication pulse code modulation serial I/O.
If CRB[FSL1] is set, the receive frame sync pulses active for one bit clock immediately
before the data transfer period. This frame sync length is compatible with Intel and
National Semiconductor Corporation components, codecs, and telecommunication pulse
code modulation serial I/O.
8.3.5 Frame Sync Length for Multiple Devices
The ability to mix frame sync lengths is useful to configure systems in which data is received
from one type of device (for example, codec) and transmitted to a different type of device.
CRB[FSL0] controls whether RX and TX have the same frame sync length.
„
„
If CRB[FSL0] is cleared, both RX and TX have the same frame sync length.
If CRB[FSL0] is set, RX and TX have different frame sync lengths.
CRB[FSL0] is ignored when CRB[SYN] is set.
DSP56321 Reference Manual, Rev. 1
8-10
Freescale Semiconductor
Operating Modes: Normal, Network, and On-Demand
8.3.6 Word Length Frame Sync and Data Word Timing
The CRB[FSR] bit controls the relative timing of the word length frame sync relative to the data
word timing.
„
„
When CRB[FSR] is cleared, the word length frame sync is generated (or expected) with
the first bit of the data word.
When CRB[FSR] is set, the word length frame sync is generated (or expected) with the
last bit of the previous word.
CRB[FSR] is ignored when a bit length frame sync is selected.
8.3.7 Frame Sync Polarity
The CRB[FSP] bit controls the polarity of the frame sync.
„
„
When CRB[FSP] is cleared, the polarity of the frame sync is positive; that is, the frame
sync signal is asserted high. The ESSI synchronizes on the leading edge of the frame sync
signal.
When CRB[FSP] is set, the polarity of the frame sync is negative; that is, the frame sync is
asserted low. The ESSI synchronizes on the trailing edge of the frame sync signal.
The ESSI receiver looks for a receive frame sync edge (leading edge if CRB[FSP] is cleared,
trailing edge if FSP is set) only when the previous frame is completed. If the frame sync is
asserted before the frame is completed (or before the last bit of the frame is received in the case
of a bit frame sync or a word-length frame sync with CRB[FSR] set), the current frame sync is
not recognized, and the receiver is internally disabled until the next frame sync.
Frames do not have to be adjacent; that is, a new frame sync does not have to follow the previous
frame immediately. Gaps of arbitrary periods can occur between frames. All the enabled
transmitters are tri-stated during these gaps.
8.3.8 Byte Format (LSB/MSB) for the Transmitter
Some devices, such as CODECs, require a MSB-first data format. Other devices, such as those
that use the AES–EBU digital audio format, require the LSB first. To be compatible with all
formats, the shift registers in the ESSI are bidirectional. You select either MSB or LSB by
programming CRB[SHFD].
„
„
If CRB[SHFD] is cleared, data is shifted into the receive shift register MSB first and
shifted out of the transmit shift register MSB first.
If CRB[SHFD] is set, data is shifted into the receive shift register LSB first and shifted out
of the transmit shift register LSB first.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-11
Enhanced Synchronous Serial Interface
8.3.9 Flags
Two ESSI signals (SC[1–0]) are available for use as serial I/O flags. Their operation is controlled
by the SYN, SCD[1–0], SSC1, and TE[2–1] bits in the CRB/CRA.The control bits OF[1–0] and
status bits IF[1–0] are double-buffered to and from SC[1–0]. Double-buffering the flags keeps
the flags in sync with TX and RX.
The SC[1–0] flags are available in Synchronous mode only. Each flag can be separately
programmed. The SC0 flag is enabled when transmitter 1 is disabled (TE1 = 0). The flag’s
direction is selected by the SCD0 bit. When SCD0 is set, SC0 is configured as output. When
SCD0 is cleared, SC0 is configured as input. Similarly, the SC1 flag is enabled when transmitter 2
is disabled (TE2 = 0), and the SC1 signal is not configured as the transmitter 0 drive-enabled
signal (Bit SSC1 = 0). The direction of SC1 is determined by the SCD1 bit. When SCD1 is set,
SC1 is an output flag. When SCD1 is cleared, SC1 is an input flag.
When programmed as input flags, the value of the SC[1–0] bits is latched at the same time as the
first bit of the received data word is sampled. Once the input is latched, the signal on the input
flag signal (SC0 and SC1) can change without affecting the input flag. The value of SC[1–0] does
not change until the first bit of the next data word is received. When the received data word is
latched by RX, the latched values of SC[1–0] are latched by the SSISR IF[1–0] bits, respectively,
and can be read by software.
When they are programmed as output flags, the value of the SC[1–0] bits is taken from the value
of the OF[1–0] bits. The value of OF[1–0] is latched when the contents of TX transfer to the
transmit shift register. The value on SC[1–0] is stable from the time the first bit of the transmit
data word transmits until the first bit of the next transmit data word transmits. Software can
directly set the OF[1–0] values, allowing the DSP56321 to control data transmission by indirectly
controlling the value of the SC[1–0] flags.
8.4 ESSI Programming Model
The ESSI is composed of the following registers:
„
„
„
„
„
„
„
„
„
Two control registers (CRA, CRB), page 8-13 and page 8-17
One status register (SSISR), page 8-26
One Receive Shift Register, page 8-27
One Receive Data Register (RX), page 8-28
Three Transmit Shift Registers, page 8-28
Three Transmit Data Registers (TX0, TX1, TX2), page 8-28
One special-purpose Time Slot Register (TSR), page 8-31
Two Transmit Slot Mask Registers (TSMA, TSMB), page 8-31
Two Receive Slot Mask Registers (RSMA, RSMB), page 8-32
DSP56321 Reference Manual, Rev. 1
8-12
Freescale Semiconductor
ESSI Programming Model
This section discusses the ESSI registers and describes their bits. Section 8.5, GPIO Signals and
Registers, on page 8-33 covers ESSI GPIO.
8.4.1 ESSI Control Register A (CRA)
The ESSI Control Register A (CRA) is one of two 24-bit read/write control registers that direct
the operation of the ESSI. CRA controls the ESSI clock generator bit and frame sync rates, word
length, and number of words per frame for serial data.
23
22
21
20
19
18
SSC1
WL2
WL1
WL0
ALC
10
9
8
7
6
PM7
PM6
11
PSR
17
16
15
14
13
12
DC4
DC3
DC2
DC1
DC0
5
4
3
2
1
0
PM5
PM4
PM3
PM2
PM1
PM0
—Reserved bit; read as 0; write to 0 for future compatibility.
(ESSI0 X:$FFFFB5, ESSI1 X:$FFFFA5)
Table 8-3. ESSI Control Register A (CRA) Bit Definitions
Bit Number
Bit Name
23
22
SSC1
Reset
Value
Description
0
Reserved. Write to 0 for future compatibility.
0
Select SC1
Controls the functionality of the SC1 signal. If SSC1 is set, the ESSI is
configured in Synchronous mode (the CRB synchronous/asynchronous bit
(SYN) is set), and transmitter 2 is disabled (transmit enable (TE2) = 0), then the
SC1 signal acts as the transmitter 0 driver-enabled signal while the SC1 signal is
configured as output (SCD1 = 1). This configuration enables an external buffer
for the transmitter 0 output. If SSC1 is cleared, the ESSI is configured in
Synchronous mode (SYN = 1), and transmitter 2 is disabled (TE2 = 0), then the
SC1 acts as the serial I/O flag while the SC1 signal is configured as output
(SCD1 = 1).
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-13
Enhanced Synchronous Serial Interface
Table 8-3. ESSI Control Register A (CRA) Bit Definitions (Continued)
Bit Number
Bit Name
Reset
Value
21–19
WL[2–0]
0
Description
Word Length Control
Select the length of the data words transferred via the ESSI. Word lengths of 8-,
12-, 16-, 24-, or 32-bits can be selected. The ESSI data path programming
model in Figure 8-8 and Figure 8-9 shows additional information on how to
select different lengths for data words. The ESSI data registers are 24 bits long.
The ESSI transmits 32-bit words in one of two ways:
• by duplicating the last bit 8 times when WL[2–0] = 100
• by duplicating the first bit 8 times when WL[2–0] = 101.
Note:
When WL[2–0] = 100, the ESSI is designed to duplicate the last bit of
the 24-bit transmission eight times to fill the 32-bit shifter. Instead, after
the 24-bit word is shifted correctly, eight zeros (0s) are shifted.
ESSI Word Length Selection
WL2
WL1
WL0
Number of Bits/Word
0
0
0
8
0
0
1
12
0
1
0
16
0
1
1
24
1
0
0
32
(valid data in the first 24 bits)
1
0
1
32
(valid data in the last 24
bits)
1
1
0
Reserved
1
1
1
Reserved
Note:
18
ALC
0
Alignment Control
The ESSI handles 24-bit fractional data. Shorter data words are left-aligned to
the MSB, bit 23. For applications that use 16-bit fractional data, shorter data
words are left-aligned to bit 15. The ALC bit supports shorter data words. If ALC
is set, received words are left-aligned to bit 15 in the receive shift register.
Transmitted words must be left-aligned to bit 15 in the transmit shift register. If
the ALC bit is cleared, received words are left-aligned to bit 23 in the receive
shift register. Transmitted words must be left-aligned to bit 23 in the transmit shift
register.
Note:
17
When the ESSI transmits data in On-Demand mode (that is, MOD = 1
in the CRB and DC[4–0]=00000 in the CRA) with WL[2–0] = 100, the
transmission does not work properly. To ensure correct operation, do
not use On-Demand mode with the WL[2–0] = 100 32-bit word length
mode.
If the ALC bit is set, only 8-, 12-, or 16-bit words are used. The use of
24- or 32-bit words leads to unpredictable results.
Reserved. Write to 0 for future compatibility.
DSP56321 Reference Manual, Rev. 1
8-14
Freescale Semiconductor
ESSI Programming Model
Table 8-3. ESSI Control Register A (CRA) Bit Definitions (Continued)
Bit Number
Bit Name
Reset
Value
16–12
DC[4–0]
0
Frame Rate Divider Control
Control the divide ratio for the programmable frame rate dividers that generate
the frame clocks. In Network mode, this ratio is the number of words per frame
minus one. In Normal mode, this ratio determines the word transfer rate. The
divide ratio ranges from 1 to 32 (DC = 00000 to 11111) for Normal mode and 2
to 32 (DC = 00001 to 11111) for Network mode. A divide ratio of one (DC =
00000) in Network mode is a special case known as On-Demand mode. In
Normal mode, a divide ratio of one (DC = 00000) provides continuous periodic
data word transfers. A bit-length frame sync must be used in this case; you
select it by setting the FSL[1–0] bits in the CRA to (01). Figure 8-2 shows the
ESSI frame sync generator functional block diagram.
11
PSR
0
Prescaler Range
Controls a fixed divide-by-eight prescaler in series with the variable prescaler.
This bit extends the range of the prescaler when a slower bit clock is needed.
When PSR is set, the fixed prescaler is bypassed. When PSR is cleared, the
fixed divide-by-eight prescaler is operational, as in Figure 8-1. This definition is
reversed from that of the SSI in other DSP56000 family members. The
maximum allowed internally generated bit clock frequency is the internal
DSP56321 clock frequency divided by 4; the minimum possible internally
generated bit clock frequency is the DSP56321 internal clock frequency divided
by 4096.
Description
Note:
10–8
7–0
PM[7–0]
The combination PSR = 1 and PM[7–0] = $00 (dividing Fcore by 2) can
cause synchronization problems and thus should not be used.
0
Reserved. Write to 0 for future compatibility.
0
Prescale Modulus Select
Specify the divide ratio of the prescale divider in the ESSI clock generator. A
divide ratio from 1 to 256 (PM = $0 to $FF) can be selected. The bit clock output
is available at the transmit clock signal (SCK) and/or the receive clock (SC0)
signal of the DSP. The bit clock output is also available internally for use as the
bit clock to shift the transmit and receive shift registers. Figure 8-1 shows the
ESSI clock generator functional block diagram. Fcore is the DSP56321 core
clock frequency (the same frequency as the enabled CLKOUT signal). Careful
choice of the crystal oscillator frequency and the prescaler modulus can
generate the industry-standard CODEC master clock frequencies of 2.048 MHz,
1.544 MHz, and 1.536 MHz.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-15
Enhanced Synchronous Serial Interface
TX 1 or Flag0 Out
Flag0 In
CRB(TE1) CRB(OF0) SSISR(IF0)
(Sync Mode)
(Sync Mode)
CRA(WL2–0)
RX
Word
Clock
/8, /12, /16, /24,
SCn0
Sync:
TX 1, or
Flag0
Async:
CRB(SCD0)
RX clk
SYN = 0
0
SCD0 = 0
SYN = 0
CRB(SYN) =
2
3 4,5
RX Shift Register
SCD0 = 1
RCLOCK
SYN = 1
CRA(WL2–0)
TCLOCK
TX
Word
Clock
/8, /12, /16, /24,
0 1
Internal Bit Clock
SCKn
Sync:
TX/RX clk
Async:
CRB(SCKD)
TX clk
1
2
3 4,5
TX Shift Register
Notes: 1.
/2
CRA(PSR)
CRA(PM7:0)
/1 or /8
/1 to /256
0
1
(Opposite
from SSI)
FCORE
0
2.
255
3.
FCORE is the DSP56300 core
internal clock frequency.
ESSI internal clock range:
min = FOSC/4096
max = FOSC/4
‘n’ in signal name is ESSI # (0
or 1)
Figure 8-2. ESSI Clock Generator Functional Block Diagram
RX
Word
CRB(FSL1)
CRB(FSR)
CRA(DC4:0)
SyncType
/1 to /32
0
Internal Rx Frame Sync
CRB(SCD1)
31
CRB(SCD1) = 1
Receive
Control
Logic
CRB(SYN) = 0
Receive
Frame Sync
SCD1 =
SYN = 0
SYN = 1
SYN =
These signals are
identical in sync mode.
Flag1 In
TX 2, Flag1 Out, or drive enb.
SSISR(IF1)
CRB(TE2) CRB(OF1) CRA(SSC1)
(Sync Mode)
(Sync Mode)
CRB(FSL[1–0])
CRB(FSR)
TX Word
Clock
SCn1
Sync:
TX 2 Flag1,
or drive enb.
Async:
RX F.S.
CRB(SCD2)
CRA(DC4–0)
/1 to /32
0
31
Transmit
Control
Logic
Sync
Type
Internal TX Frame Sync
Transmit
Frame Sync
SCn2
Sync:
TX/RX F.S.
Async:
TX F.S.
Figure 8-3. ESSI Frame Sync Generator Functional Block Diagram
DSP56321 Reference Manual, Rev. 1
8-16
Freescale Semiconductor
ESSI Programming Model
8.4.2 ESSI Control Register B (CRB)
CRB is one of two read/write control registers that direct the operation of the ESSI. The CRB bit
definitions are presented in Table 8-4. CRB controls the ESSI multifunction signals, SC[2–0],
which can be used as clock inputs or outputs, frame synchronization signals, transmit data
signals, or serial I/O flag signals.
23
22
21
20
19
18
17
16
15
14
13
12
REIE
TEIE
RLIE
TLIE
RIE
TIE
RE
TE0
TE1
TE2
MOD
SYN
11
10
9
8
7
6
5
4
3
2
1
0
CKP
FSP
FSR
FSL1
FSL0
SHFD
SCKD
SCD2
SCD1
SCD0
OF1
OF0
(ESSI0 X:$FFFFB6, ESSI1 X:$FFFFA6)
The CRB contains the serial output flag control bits and the direction control bits for the serial
control signals. Also in the CRB are interrupt enable bits for the receiver and the transmitter. Bit
settings of the CRB determines how many transmitters are enabled: 0, 1, 2, or 3. The CRB
settings also determine the ESSI operating mode. Either a hardware RESET signal or a software
RESET instruction clears all the bits in the CRB. Table 8-2, Mode and Signal Definitions, on
page 8-4 summarizes the relationship between the ESSI signals SC[2–0], SCK, and the CRB bits.
The ESSI has two serial output flag bits, OF1 and OF0. The normal sequence follows for setting
output flags when transmitting data (by transmitter 0 through the STD signal only).
1.
Wait for TDE (TX0 empty) to be set.
2.
Write the flags.
3.
Write the transmit data to the TX register
Bits OF0 and OF1 are double-buffered so that the flag states appear on the signals when the TX
data is transferred to the transmit shift register. The flag bit values are synchronized with the data
transfer. The timing of the optional serial output signals SC[2–0] is controlled by the frame timing
and is not affected by the settings of TE2, TE1, TE0, or the receive enable (RE) bit of the CRB.
The ESSI has three transmit enable bits (TE[2–0]), one for each data transmitter. The process of
transmitting data from TX1 and TX2 is the same. TX0 differs from these two bits in that it can
also operate in Asynchronous mode. The normal transmit enable sequence is to write data to one
or more transmit data registers (or the Time Slot Register (TSR)) before you set the TE bit. The
normal transmit disable sequence is to set the Transmit Data Empty (TDE) bit and then to clear
the TE, Transmit Interrupt Enable (TIE), and Transmit Exception Interrupt Enable (TEIE) bits. In
Network mode, if you clear the appropriate TE bit and set it again, then you disable the
corresponding transmitter (0, 1, or 2) after transmission of the current data word. The transmitter
remains disabled until the beginning of the next frame. During that time period, the
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Freescale Semiconductor
8-17
Enhanced Synchronous Serial Interface
corresponding SC (or STD in the case of TX0) signal remains in a high-impedance state. The
CRB bits are cleared by either a hardware RESET signal or a software RESET instruction.
Table 8-4. ESSI Control Register B (CRB) Bit Definitions
Bit Number
Bit Name
Reset Value
Description
23
REIE
0
Receive Exception Interrupt Enable
When the REIE bit is set, the DSP is interrupted when both RDF and ROE in
the ESSI status register are set. When REIE is cleared, this interrupt is
disabled. The receive interrupt is documented in
Section 8.2.3, Exceptions, on page 8-7. A read of the status register
followed by a read of the receive data register clears both ROE and the
pending interrupt.
22
TEIE
0
Transmit Exception Interrupt Enable
When the TEIE bit is set, the DSP is interrupted when both TDE and TUE in
the ESSI status register are set. When TEIE is cleared, this interrupt is
disabled. The use of the transmit interrupt is documented
in Section 8.2.3, Exceptions, on page 8-7. A read of the status register,
followed by a write to all the data registers of the enabled transmitters, clears
both TUE and the pending interrupt.
21
RLIE
0
Receive Last Slot Interrupt Enable
Enables/disables an interrupt after the last slot of a frame ends when the
ESSI is in Network mode. When RLIE is set, the DSP is interrupted after the
last slot in a frame ends regardless of the receive mask register setting.
When RLIE is cleared, the receive last slot interrupt is disabled. The use of
the receive last slot interrupt is documented in
Section 8.2.3, Exceptions, on page 8-7. RLIE is disabled when the ESSI is
in On-Demand mode (DC = $0).
20
TLIE
0
Transmit Last Slot Interrupt Enable
Enables/disables an interrupt at the beginning of the last slot of a frame
when the ESSI is in Network mode. When TLIE is set, the DSP is interrupted
at the start of the last slot in a frame regardless of the transmit mask register
setting. When TLIE is cleared, the transmit last slot interrupt is disabled. The
transmit last slot interrupt is documented in Section 8.2.3, Exceptions, on
page 8-7. TLIE is disabled when the ESSI is in On-Demand mode (DC = $0).
19
RIE
0
Receive Interrupt Enable
Enables/disables a DSP receive data interrupt; the interrupt is generated
when both the RIE and receive data register full (RDF) bit (in the SSISR) are
set. When RIE is cleared, this interrupt is disabled. The receive interrupt is
documented in Section 8.2.3, Exceptions, on page 8-7. When the receive
data register is read, it clears RDF and the pending interrupt. Receive
interrupts with exception have higher priority than normal receive data
interrupts. If the receiver overrun error (ROE) bit is set (signaling that an
exception has occurred) and the REIE bit is set, the ESSI requests an SSI
receive data with exception interrupt from the interrupt controller.
18
TIE
0
Transmit Interrupt Enable
Enables/disables a DSP transmit interrupt; the interrupt is generated when
both the TIE and the TDE bits in the ESSI status register are set. When TIE
is cleared, the transmit interrupt is disabled. The transmit interrupt is
documented in Section 8.2.3. When data is written to the data registers of
the enabled transmitters or to the TSR, it clears TDE and also clears the
interrupt. Transmit interrupts with exception conditions have higher priority
than normal transmit data interrupts. If the transmitter underrun error (TUE)
bit is set (signaling that an exception has occurred) and the TEIE bit is set,
the ESSI requests an SSI transmit data with exception interrupt from the
interrupt controller.
DSP56321 Reference Manual, Rev. 1
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Freescale Semiconductor
ESSI Programming Model
Table 8-4. ESSI Control Register B (CRB) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
17
RE
0
Receive Enable
Enables/disables the receive portion of the ESSI. When RE is cleared, the
receiver is disabled: data transfer into RX is inhibited. If data is being
received while this bit is cleared, the remainder of the word is shifted in and
transferred to the ESSI receive data register. RE must be set in both Normal
and On-Demand modes for the ESSI to receive data. In Network mode,
clearing RE and setting it again disables the receiver after reception of the
current data word. The receiver remains disabled until the beginning of the
next data frame. The setting of the RE bit does not affect the generation of a
frame sync.
16
TE0
0
Transmit 0 Enable
Enables the transfer of data from TX0 to Transmit Shift Register 0. TE0 is
functional when the ESSI is in either synchronous or Asynchronous mode.
When TE0 is set and a frame sync is detected, the transmitter 0 is enabled
for that frame. When TE0 is cleared, transmitter 0 is disabled after the
transmission of data currently in the ESSI transmit shift register. The STD
output is tri-stated, and any data present in TX0 is not transmitted. In other
words, data can be written to TX0 with TE0 cleared; the TDE bit is cleared,
but data is not transferred to the transmit shift register 0. The transmit enable
sequence in On-Demand mode can be the same as in Normal mode, or TE0
can be left enabled. Transmitter 0 is the only transmitter that can operate in
Asynchronous mode (SYN = 0). The setting of the TE0 bit does not affect
the generation of frame sync or output flags.
15
TE1
0
Transmit 1 Enable
Enables the transfer of data from TX1 to Transmit Shift Register 1. TE1 is
functional only when the ESSI is in Synchronous mode and is ignored when
the ESSI is in Asynchronous mode. When TE1 is set and a frame sync is
detected, transmitter 1 is enabled for that frame. When TE1 is cleared,
transmitter 1 is disabled after completing transmission of data currently in
the ESSI transmit shift register. Any data present in TX1 is not transmitted. If
TE1 is cleared, data can be written to TX1; the TDE bit is cleared, but data is
not transferred to transmit shift register 1. If the TE1 bit is kept cleared until
the start of the next frame, it causes the SC0 signal to act as serial I/O flag
from the start of the frame in both Normal and Network mode. The transmit
enable sequence in On-Demand mode can be the same as in Normal mode,
or the TE1 bit can be left enabled. The setting of the TE1 bit does not affect
the generation of frame sync or output flags.
14
TE2
0
Transmit 2 Enable
Enables the transfer of data from TX2 to Transmit Shift Register 2. TE2 is
functional only when the ESSI is in Synchronous mode and is ignored when
the ESSI is in Asynchronous mode. When TE2 is set and a frame sync is
detected, transmitter 2 is enabled for that frame.
When TE2 is cleared, transmitter 2 is disabled after completing transmission
of data currently in the ESSI transmit shift register. Any data present in TX2
is not transmitted. If TE2 is cleared, data can be written to TX2; the TDE bit
is cleared, but data is not transferred to transmit shift register 2. If the TE2 bit
is kept cleared until the start of the next frame, it causes the SC1 signal to
act as a serial I/O flag from the start of the frame in both Normal mode and
Network mode. The transmit enable sequence in On-Demand mode can be
the same as in Normal mode, or the TE2 bit can be left enabled. The setting
of the TE2 bit does not affect the generation of frame sync or output flags.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-19
Enhanced Synchronous Serial Interface
Table 8-4. ESSI Control Register B (CRB) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
13
MOD
0
Mode Select
Selects the operational mode of the ESSI, as in Figure 8-5 on page -24,
Figure 8-6 on page -25, and Figure 8-7 on page -25. When MOD is cleared,
the Normal mode is selected; when MOD is set, the Network mode is
selected. In Normal mode, the frame rate divider determines the word
transfer rate: one word is transferred per frame sync during the frame sync
time slot. In Network mode, a word can be transferred every time slot. For
details, see Section 8.2.
12
SYN
0
Synchronous/Asynchronous
Controls whether the receive and transmit functions of the ESSI occur
synchronously or asynchronously with respect to each other. (See Figure
8-4 on page -23.) When SYN is cleared, the ESSI is in Asynchronous mode,
and separate clock and frame sync signals are used for the transmit and
receive sections. When SYN is set, the ESSI is in Synchronous mode, and
the transmit and receive sections use common clock and frame sync signals.
Only in Synchronous mode can more than one transmitter be enabled.
11
CKP
0
Clock Polarity
Controls which bit clock edge data and frame sync are clocked out and
latched in. If CKP is cleared, the data and the frame sync are clocked out on
the rising edge of the transmit bit clock and latched in on the falling edge of
the receive bit clock. If CKP is set, the data and the frame sync are clocked
out on the falling edge of the transmit bit clock and latched in on the rising
edge of the receive bit clock.
10
FSP
0
Frame Sync Polarity
Determines the polarity of the receive and transmit frame sync signals.
When FSP is cleared, the frame sync signal polarity is positive; that is, the
frame start is indicated by the frame sync signal going high. When FSP is
set, the frame sync signal polarity is negative; that is, the frame start is
indicated by the frame sync signal going low.
9
FSR
0
Frame Sync Relative Timing
Determines the relative timing of the receive and transmit frame sync signal
in reference to the serial data lines for word length frame sync only. When
FSR is cleared, the word length frame sync occurs together with the first bit
of the data word of the first slot. When FSR is set, the word length frame
sync occurs one serial clock cycle earlier (that is, simultaneously with the
last bit of the previous data word).
8–7
FSL[1–0]
0
Frame Sync Length
Selects the length of frame sync to be generated or recognized, as in Figure
8-3 on page -22, Figure 8-6 on page -25, and Figure 8-7 on page -25.
6
SHFD
0
Frame Sync Length
TX
FSL1
FSL0
0
0
word
word
0
1
word
bit
1
0
bit
bit
1
1
bit
word
RX
Shift Direction
Determines the shift direction of the transmit or receive shift register. If
SHFD is set, data is shifted in and out with the LSB first. If SHFD is cleared,
data is shifted in and out with the MSB first, as in Figure 8-8 on page -29
and Figure 8-9 on page -30.
DSP56321 Reference Manual, Rev. 1
8-20
Freescale Semiconductor
ESSI Programming Model
Table 8-4. ESSI Control Register B (CRB) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
5
SCKD
0
Clock Source Direction
Selects the source of the clock signal that clocks the transmit shift register in
Asynchronous mode and both the transmit and receive shift registers in
Synchronous mode. If SCKD is set and the ESSI is in Synchronous mode,
the internal clock is the source of the clock signal used for all the transmit
shift registers and the receive shift register. If SCKD is set and the ESSI is in
Asynchronous mode, the internal clock source becomes the bit clock for the
transmit shift register and word length divider. The internal clock is output on
the SCK signal. When SCKD is cleared, the external clock source is
selected. The internal clock generator is disconnected from the SCK signal,
and an external clock source may drive this signal.
4
SCD2
0
Serial Control Direction 2
Controls the direction of the SC2 I/O signal. When SCD2 is set, SC2 is an
output; when SCD2 is cleared, SC2 is an input.
NOTE: Programming the ESSI to use an internal frame sync (that is, SCD2
= 1 in CRB) causes the SC2 and SC1 signals to be programmed as outputs.
However, if the corresponding multiplexed pins are programmed by the Port
Control Register (PCR) to be GPIOs, the GPIO Port Direction Register
(PRR) chooses their direction. The ESSI uses an external frame sync if
GPIO is selected. To assure correct operation, either program the GPIO pins
as outputs or configure the pins in the PCR as ESSI signals. The default
selection for these signals after reset is GPIO. This note applies to both
ESSI0 and ESSI1.
3
SCD1
0
Serial Control Direction 1
In Synchronous mode (SYN = 1) when transmitter 2 is disabled (TE2 = 0), or
in Asynchronous mode (SYN = 0), SCD1 controls the direction of the SC1
I/O signal. When SCD1 is set, SC1 is an output; when SCD1 is cleared, SC1
is an input. When TE2 is set, the value of SCD1 is ignored and the SC1
signal is always an output.
2
SCD0
0
Serial Control Direction 0
In Synchronous mode (SYN = 1) when transmitter 1 is disabled (TE1 = 0), or
in Asynchronous mode (SYN = 0), SCD0 controls the direction of the SC0
I/O signal. When SCD0 is set, SC0 is an output; when SCD0 is cleared, SC0
is an input. When TE1 is set, the value of SCD0 is ignored and the SC0
signal is always an output.
1
OF1
0
Serial Output Flag 1
In Synchronous mode (SYN = 1), when transmitter 2 is disabled (TE2 = 0),
the SC1 signal is configured as ESSI flag 1. When SCD1 is set, SC1 is an
output. Data present in bit OF1 is written to SC1 at the beginning of the
frame in Normal mode or at the beginning of the next time slot in Network
mode.
0
OF0
0
Serial Output Flag 0
In Synchronous mode (SYN = 1), when transmitter 1 is disabled (TE1 = 0),
the SC0 signal is configured as ESSI flag 0. When SCD0 is set, the SC0
signal is an output. Data present in Bit OF0 is written to SC0 at the beginning
of the frame in Normal mode or at the beginning of the next time slot in
Network mode.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-21
Enhanced Synchronous Serial Interface
Word Length: FSL1 = 0, FSL0 = 0
Serial Clock
RX, TX Frame SYNC
RX, TX Serial Data
Data
Data
NOTE: Frame sync occurs while data is valid.
One Bit Length: FSL1 = 1, FSL0 = 0
Serial Clock
RX, TX Frame SYNC
RX, TX Serial Data
Data
Data
NOTE: Frame sync occurs for one bit time preceding the data.
Mixed Frame Length: FSL1 = 0, FSL0 = 1
Serial Clock
RX Frame Sync
RXSerial Data
Data
Data
Data
Data
TX Frame SYNC
TX Serial Data
Mixed Frame Length: FSL1 = 1, FSL0 = 1
Serial Clock
RX Frame SYNC
RX Serial Data
Data
Data
TX Frame SYNC
TX Serial Data
Data
Data
Figure 8-4. CRB FSL0 and FSL1 Bit Operation (FSR = 0)
DSP56321 Reference Manual, Rev. 1
8-22
Freescale Semiconductor
ESSI Programming Model
Asynchronous (SYN = 0)
Transmitter
Clock
SCK
External Transmit Clock
External Transmit Frame
Internal Clock
Internal Frame SYNC
External Receive Clock
External Receive Frame
ESSI Bit
Clock
SC0
STD
Frame
SYNC
Clock
Frame
SYNC
SC2
SC1
SR
Receiver
NOTE: Transmitter and receiver may have different clocks and frame syncs.
SYNCHRONOUS (SYN = 1)
Transmitter
Frame
SYNC
Clock
SCK
ESSI Bit
Clock
ST
External Clock
External Frame SYNC
Internal Clock
Internal Frame SYNC
Clock
Frame
SYNC
SC2
SRD
Receiver
NOTE: Transmitter and receiver may have the same clock frame syncs.
Figure 8-5. CRB SYN Bit Operation
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-23
8-24
Data
Slot 1
Slot 2
Slot 1
Receiver Interrupt (or DMA Request) and Flags Set
Slot 3
Transmitter Interrupts (or DMA Request) and
Network Mode (MOD = 1)
NOTE: Interrupts occur every time slot and a word may be transferred.
Serial Data
Frame SYNC
Serial Clock
Data
Receiver Interrupt (or DMA Request) and Flags
Transmitter Interrupt (or DMA Request) and
NOTE: Interrupts occur and data is transferred once per frame sync.
Serial Data
Frame SYNC
Serial Clock
Normal Mode (MOD = 0)
Slot 2
SSI Control Register B (CRB)
(READ/WRITE)
Enhanced Synchronous Serial Interface
Figure 8-6. CRB MOD Bit Operation
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
ESSI Programming Model
Frame SYNC
(FSL0 = 0, FSL1 = 0)
Frame SYNC
(FSL0 = 0, FSL1 = 1)
Data Out
Flags
Slot 0
Wait
Slot 0
Figure 8-7. Normal Mode, External Frame Sync (8 Bit, 1 Word in Frame)
Frame SYNC
(FSL0 = 0, FSL1 = 0)
Frame SYNC
(FSL0 = 0, FSL1 = 1)
Data
Flags
SLOT 0
SLOT 1
SLOT 0
SLOT 1
Figure 8-8. Network Mode, External Frame Sync (8 Bit, 2 Words in Frame)
8.4.3 ESSI Status Register (SSISR)
The SSISR is a read-only status register by which the DSP reads the ESSI status and serial input
flags.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RDF
TDE
ROE
TUE
RFS
TFS
IF1
IF0
—Reserved bit; read as 0; write to 0 0 for future compatibility.
(ESSI0 X:$FFFFB7, ESSI1 X:$FFFFA7)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-25
Enhanced Synchronous Serial Interface
Table 8-5. ESSI Status Register (SSISR) Bit Definitions
Bit Number
Bit Name
23–8
Reset Value
Description
0
Reserved. Write to 0 for future compatibility.
7
RDF
0
Receive Data Register Full
Set when the contents of the receive shift register transfer to the receive data
register. RDF is cleared when the DSP reads the receive data register. If RIE
is set, a DSP receive data interrupt request is issued when RDF is set.
6
TDE
0
Transmit Data Register Empty
Set when the contents of the transmit data register of every enabled
transmitter are transferred to the transmit shift register. It is also set for a TSR
disabled time slot period in Network mode (as if data were being transmitted
after the TSR has been written). When TDE is set, TDE data is written to all
the TX registers of the enabled transmitters or to the TSR. The TDE bit is
cleared when the DSP writes to all the transmit data registers of the enabled
transmitters, or when the DSP writes to the TSR to disable transmission of the
next time slot. If the TIE bit is set, a DSP transmit data interrupt request is
issued when TDE is set.
5
ROE
0
Receiver Overrun Error Flag
Set when the serial receive shift register is filled and ready to transfer to the
receive data register (RX) but RX is already full (that is, the RDF bit is set). If
the REIE bit is set, a DSP receiver overrun error interrupt request is issued
when the ROE bit is set. The programmer clears ROE by reading the SSISR
with the ROE bit set and then reading the RX.
4
TUE
0
Transmitter Underrun Error Flag
Set when at least one of the enabled serial transmit shift registers is empty
(that is, there is no new data to be transmitted) and a transmit time slot
occurs. When a transmit underrun error occurs, the previous data (which is
still present in the TX registers not written) is retransmitted. In Normal mode,
there is only one transmit time slot per frame. In Network mode, there can be
up to 32 transmit time slots per frame. If the TEIE bit is set, a DSP transmit
underrun error interrupt request is issued when the TUE bit is set. The
programmer can also clear TUE by first reading the SSISR with the TUE bit
set, then writing to all the enabled transmit data registers or to the TSR.
3
RFS
0
Receive Frame Sync Flag
When set, the RFS bit indicates that a receive frame sync occurred during the
reception of a word in the serial receive data register. In other words, the data
word is from the first time slot in the frame. When the RFS bit is cleared and a
word is received, it indicates (only in Network mode) that the frame sync did
not occur during reception of that word. RFS is valid only if the receiver is
enabled (that is, if the RE bit is set).
NOTE: In Normal mode, RFS is always read as 1 when data is read because
there is only one time slot per frame, the frame sync time slot.
2
TFS
0
Transmit Frame Sync Flag
When set, TFS indicates that a transmit frame sync occurred in the current
time slot. TFS is set at the start of the first time slot in the frame and cleared
during all other time slots. If the transmitter is enabled, data written to a
transmit data register during the time slot when TFS is set is transmitted (in
Network mode) during the second time slot in the frame. TFS is useful in
Network mode to identify the start of a frame. TFS is valid only if at least one
transmitter is enabled that is, when TE0, TE1, or TE2 is set). In Normal mode,
TFS is always read as 1 when data is being transmitted because there is only
one time slot per frame, the frame sync time slot.
DSP56321 Reference Manual, Rev. 1
8-26
Freescale Semiconductor
ESSI Programming Model
Table 8-5. ESSI Status Register (SSISR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
1
IF1
0
Serial Input Flag 1
The ESSI latches any data on the SC1 signal during reception of the first
received bit after the frame sync is detected. IF1 is updated with this data
when the data in the receive shift register transfers into the receive data
register. IF1 is enabled only when SC1 is an input flag and Synchronous
mode is selected; that is, when SC1 is programmed as ESSI in the port
control register (PCR), the SYN bit is set, and the TE2 and SCD1 bits are
cleared. If it is not enabled, IF1 is cleared.
0
IF0
0
Serial Input Flag 0
The ESSI latches any data on the SC0 signal during reception of the first
received bit after the frame sync is detected. The IF0 bit is updated with this
data when the data in the receive shift register transfers into the receive data
register. IF0 is enabled only when SC0 is an input flag and the Synchronous
mode is selected; that is, when SC0 is programmed as ESSI in the port
control register (PCR), the SYN bit is set, and the TE1 and SCD0 bits are
cleared. If it is not enabled, the IF0 bit is cleared.
8.4.4 ESSI Receive Shift Register
The 24-bit Receive Shift Register (see Figure 8-8 and Figure 8-9) receives incoming data from
the serial receive data signal. The selected (internal/external) bit clock shifts data in when the
associated frame sync I/O is asserted. Data is received MSB first if SHFD is cleared and LSB
first if SHFD is set. Data transfers to the ESSI Receive Data Register (RX) after 8, 12, 16, 24, or
32 serial clock cycles are counted, depending on the word length control bits in the CRA.
8.4.5 ESSI Receive Data Register (RX)
The Receive Data Register (RX) is a 24-bit read-only register that accepts data from the receive
shift register as it becomes full, according to Figure 8-8 and Figure 8-9. The data read is aligned
according to the value of the ALC bit. When the ALC bit is cleared, the MSB is bit 23, and the
least significant byte is unused. When the ALC bit is set, the MSB is bit 15, and the most
significant byte is unused. Unused bits are read as 0. If the associated interrupt is enabled, the
DSP is interrupted whenever the RX register becomes full.
8.4.6 ESSI Transmit Shift Registers
The three 24-bit transmit shift registers contain the data being transmitted, as in Figure 8-8 and
Figure 8-9. Data is shifted out to the serial transmit data signals by the selected (whether internal
or external) bit clock when the associated frame sync I/O is asserted. The word-length control
bits in CRA determine the number of bits that must be shifted out before the shift registers are
considered empty and can be written again. Depending on the setting of the CRA, the number of
bits to be shifted out can be 8, 12, 16, 24, or 32. Transmitted data is aligned according to the value
of the ALC bit. When ALC is cleared, the MSB is Bit 23 and the least significant byte is unused.
When ALC is set, the MSB is Bit 15 and the most significant byte is unused. Unused bits are read
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-27
Enhanced Synchronous Serial Interface
as 0. Data shifts out of these registers MSB first if the SHFD bit is cleared and LSB first if SHFD
is set.
23
87
16 15
Receive High Byte
7
Receive Middle Byte
0 7
0
ESSI Receive Data
Register
Receive Low Byte
07
0
16 15
87
Serial 23
Receive
Receive High Byte
Receive Middle Byte
Receive Low Byte
Shift
0 7
07
Register 7
0
0
24 Bit
16 Bit
12 Bit
8 Bit
WL1, WL0
MSB
MSB
8-bit Data
LSB
0
0
SRD
Least Significant
Zero Fill
0
LSB
12-bit Data
LSB
MSB
16-bit Data
MSB
LSB
24-bit Data
NOTES:
Data is received MSB first if SHFD = 0.
24-bit fractional format (ALC = 0).
32-bit mode is not shown.
(a) Receive Registers
23
16 15
Transmit High Byte
8 7
Transmit Middle Byte
0
ESSI Transmit Data
Register
Transmit Low Byte
7
0 7
0 7
0
23
16 15
0 7
0
Transmit High Byte
STD
7
Transmit Middle Byte
0 7
MSB
MSB
MSB
8-bit Data
LSB
12-bit Data
07
0
ESSI Transmit
Shift Register
Transmit Low Byte
0
0
Least Significant
Zero Fill
0
LSB
LSB
16-bit Data
MSB
LSB
24-bit Data
(b) Transmit Registers
NOTES:
Data is transmitted MSB first if
SHFD = 0.
4-bit fractional format (ALC = 0).
32-bit mode is not shown.
Figure 8-9. ESSI Data Path Programming Model (SHFD = 0)
DSP56321 Reference Manual, Rev. 1
8-28
Freescale Semiconductor
ESSI Programming Model
23
87
16 15
Receive High Byte
Receive Middle Byte
0
ESSI Receive Data
Register (Read Only)
Receive Low Byte
7
0 7
07
0
23
16 15
07
0
Receive High Byte
SR
Receive Middle Byte
7
0 7
MSB
8-bit Data
07
LSB
0
MSB
ESSI Receive
Shift Register
Receive Low Byte
0
0
Least Significant
Zero Fill
0
LSB
12-bit Data
LSB
MSB
16-bit Data
MSB
LSB
24-bit Data
NOTES:
Data is received MSB first if SHFD = 0.
24-bit fractional format (ALC = 0).
32-bit mode is not shown.
23
16 15
87
0
ESSI Transmit Data
Register
Transmit High Byte
Transmit Middle Byte
Transmit Low Byte
(Write Only)
7
0 7
0
07
(a) Receive Registers
23
16 15
Transmit High Byte
7
07
Transmit Middle Byte
0 7
0
Transmit Low Byte
07
0
ESSI Transmit Shift
Register
24 Bit
16 Bit
12 Bit
8 Bit
MSB
8-bit Data
LSB
0
MSB
0
WL1, WL0
Least Significant
Zero Fill
LSB
12-bit Data
MSB
0
ST
LSB
16-bit Data
MSB
LSB
24-bit Data
(b) Transmit Registers
NOTES:
Data is received MSB first if SHFD = 0.
4-bit fractional format (ALC = 0).
32-bit mode is not shown.
Figure 8-10. ESSI Data Path Programming Model (SHFD = 1)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-29
Enhanced Synchronous Serial Interface
8.4.7 ESSI Transmit Data Registers (TX[2–0])
ESSI0:TX20, TX10, TX00; ESSI1:TX21, TX11, TX01
TX2, TX1, and TX0 are 24-bit write-only registers. Data written into these registers
automatically transfers to the transmit shift registers. (See Figure 8-8 and Figure 8-9.) The data
transmitted (8, 12, 16, or 24 bits) is aligned according to the value of the ALC bit. When the ALC
bit is cleared, the MSB is Bit 23. When ALC is set, the MSB is Bit 15. If the transmit data register
empty interrupt has been enabled, the DSP is interrupted whenever a transmit data register
becomes empty. When data is written to a peripheral device, there is a two-cycle pipeline delay
while any status bits affected by this operation are updated. If any of those status bits are read
during the two-cycle delay, the status bit may not reflect the current status.
8.4.8 ESSI Time Slot Register (TSR)
TSR is effectively a write-only null data register that prevents data transmission in the current
transmit time slot. For timing purposes, TSR is a write-only register that behaves as an alternative
transmit data register, except that, rather than transmitting data, the transmit data signals of all the
enabled transmitters are in the high-impedance state for the current time slot.
8.4.9 Transmit Slot Mask Registers (TSMA, TSMB)
Both transmit slot mask registers are read/write registers. When the TSMA or TSMB is read to
the internal data bus, the register contents occupy the two low-order bytes of the data bus, and the
high-order byte is filled by 0. In Network mode the transmitter(s) use these registers to determine
which action to take in the current transmission slot. Depending on the bit settings, the
transmitter(s) either tri-state the transmitter(s) data signal(s) or transmit a data word and generate
a transmitter empty condition.
23
22
21
20
19
18
17
16
15
14
13
12
TS15
TS14
TS13
TS12
11
10
9
8
7
6
5
4
3
2
1
0
TS11
TS10
TS9
TS8
TS7
TS6
TS5
TS4
TS3
TS2
TS1
TS0
—Reserved bit; read as 0; write to 0 0 for future compatibility.
(ESSI0 X:$FFFFB4, ESSI1 X:$FFFFA4)
DSP56321 Reference Manual, Rev. 1
8-30
Freescale Semiconductor
ESSI Programming Model
23
22
21
20
19
18
17
16
15
14
13
12
TS31
TS30
TS29
TS28
11
10
9
8
7
6
5
4
3
2
1
0
TS27
TS26
TS25
TS24
TS23
TS22
TS21
TS20
TS19
TS18
TS17
TS16
—Reserved bit; read as 0; write to 0 0 for future compatibility.
(ESSI0 X:$FFFFB3, ESSI1 X:$FFFFA3)
TSMA and TSMB (as in Figure 8-8 and Figure 8-9) can be seen as a single 32-bit register, TSM.
Bit n in TSM (TSn) is an enable/disable control bit for transmission in slot number N. When TSn
is cleared, all the data signals of the enabled transmitters are tri-stated during transmit time slot
number N. The data still transfers from the enabled transmit data register(s) to the transmit shift
register. However, the TDE and the TUE flags are not set. Consequently, during a disabled slot,
no transmitter empty interrupt is generated. The DSP is interrupted only for enabled slots. Data
written to the transmit data register when the transmitter empty interrupt request is serviced
transmits in the next enabled transmit time slot. When TSn is set, the transmit sequence proceeds
normally. Data transfers from the TX register to the shift register during slot number N, and the
TDE flag is set. The TSM slot mask does not conflict with the TSR. Even if a slot is enabled in
the TSM, you can chose to write to the TSR to tri-state the signals of the enabled transmitters
during the next transmission slot. Setting the bits in the TSM affects the next frame transmission.
The frame being transmitted is not affected by the new TSM setting. If the TSM is read, it shows
the current setting.
After a hardware RESET signal or software RESET instruction, the TSM register is reset to
$FFFFFFFF, enabling all 32 slots for data transmission.
8.4.10 Receive Slot Mask Registers (RSMA, RSMB)
Both receive slot mask registers are read/write registers. In Network mode, the receiver(s) use
these registers to determine which action to take in the current time slot. Depending on the setting
of the bits, the receiver(s) either tri-state the receiver(s) data signal(s) or receive a data word and
generate a receiver full condition.
23
22
21
20
19
18
17
16
15
14
13
12
RS15
RS14
RS13
RS12
11
10
9
8
7
6
5
4
3
2
1
0
RS11
RS10
RS9
RS8
RS7
RS6
RS5
RS4
RS3
RS2
RS1
RS0
—Reserved bit; read as 0; write to 0 0 for future compatibility.
(ESSI0 X:$FFFFB2, ESSI1 X:$FFFFA2)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
8-31
Enhanced Synchronous Serial Interface
23
22
21
20
19
18
17
16
15
14
13
12
RS31
RS30
RS29
RS28
11
10
9
8
7
6
5
4
3
2
1
0
RS27
RS26
RS25
RS24
RS23
RS22
RS21
RS20
RS19
RS18
RS17
RS16
–Reserved. Read as zero. Write with zero for future compatibility.
(ESSI0 X:$FFFFB1, ESSI1 X:$FFFFA1)
RSMA and RSMB can be seen as one 32-bit register, RSM. Bit n in RSM (RSn) is an
enable/disable control bit for time slot number N. When RSn is cleared, all the data signals of the
enabled receivers are tri-stated during time slot number N. Data transfers from the receive data
register(s) to the receive shift register(s), but the RDF and ROE flags are not set. Consequently,
during a disabled slot, no receiver full interrupt is generated. The DSP is interrupted only for
enabled slots. When RSn is set, the receive sequence proceeds normally. Data is received during
slot number N, and the RDF flag is set.
When the bits in the RSM are set, their setting affects the next frame transmission. The frame
transmitted is not affected by the new RSM setting. If the RSM is read, it shows the current
setting. When RSMA or RSMB is read by the internal data bus, the register contents occupy the
two low-order bytes of the data bus, and the high-order byte is filled by 0.
After a hardware RESET signal or a software RESET instruction, the RSM register is reset to
$FFFFFFFF, enabling all 32 time slots for data transmission.
8.5 GPIO Signals and Registers
The functionality of each ESSI port is controlled by three registers: port control register (PCRC,
PCRD), port direction register (PRRC, PRRD), and port data register (PDRC, PDRD).
8.5.1 Port Control Registers (PCRC and PCRD)
The read/write 24-bit PCRs control the functionality of the signal lines for ESSI0 and ESSI1.
Each of the PCR bits 5–0 controls the functionality of the corresponding signal line. When a
PCR[i] bit is set, the corresponding port signal is configured as an ESSI signal. When a PCR[i]
bit is cleared, the corresponding port signal is configured as a GPIO signal. Either a hardware
RESET signal or a software RESET instruction clears all PCR bits.
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Freescale Semiconductor
GPIO Signals and Registers
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PCx5
PCx4
PCx3
PCx2
PCx1
PCx0
Note:
For Px[5–0], a 0 selects Pxn as the signal and a 1 selects the specified ESSI signal. For ESSI0, the GPIO signals are
PC[5–0] and the ESSI signals are STD0, SRD0, SCK0, and SC0[2–0]. For ESSI1, the GPIO signals are PD[5–0] and
the ESSI signals are STD1, SRD1, SCK1, and SC1[2–0].
= Reserved. Read as zero. Write with zero for future compatibility.
8.5.2 Port Direction Registers (PRRC and PRRD)
The read/write PRRC and PRRD control the data direction of the ESSI0 and ESSI1 GPIO signals
when they are enabled by the associated Port Control Register (PCRC or PCRD, respectively).
When PRRC[i] or PRRD[i] is set, the corresponding signal is an output (GPO) signal. When
PRRC[i] or PRRD[i] is cleared, the corresponding signal is an input (GPI) signal. Either a
hardware RESET signal or a software RESET instruction clears all PRRC and PRRD bits.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PRx5
PRx4
PRx3
PRx2
PRx1
PRx0
Note:
For bits 5–0, a 0 configures PRxn as a GPI and a 1 configures PRxn as a GPO. For ESSI0, the GPIO signals are
PC[5–0]. For ESSI1, the GPIO signals are PD[5–0]. The corresponding direction bits for Port C GPIOs are PRC[5–0].
The corresponding direction bits for Port D GPIOs are PRD[5–0].
= Reserved. Read as zero. Write with zero for future compatibility.
Table 8-6 summarizes the ESSI port signal configurations
Table 8-6. ESSI Port Signal Configurations
PCRC/PCRD[i]
PRRC/PRRD[i]
Port Signal[i] Function
1
X
ESSI0/ESSI1
0
0
Port C/Port D GPI
0
1
Port C/Port D GPO
X: The signal setting is irrelevant to the Port Signal[i] function.
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Freescale Semiconductor
8-33
Enhanced Synchronous Serial Interface
8.5.3 Port Data Registers (PDRC and PDRD)
Bits 5–0 of the read/write PDRs write data to or read data from the associated ESSI GPIO signal
lines if they are configured as GPIO signals. If a port signal PC[i] or PD[i] is configured as an
input (GPI), the corresponding PDRC[i] pr PDRD[i] bit reflects the value present on the input
signal line. If a port signal PC[i] or PD[i] is configured as an output (GPO), a value written to the
corresponding PDRC[i] pr PDRD[i] bit is reflected as a value on the output signal line. Either a
hardware RESET signal or a software RESET instruction clears all PDRC and PDRD bits.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PDRx5
PDRx4
PDRx3
PDRx2
PDRx1
PDRx0
Note:
For bits 5–0, the value represents the level that is written to or read from the associated signal line if it is
enabled as a GPIO signal by the respective port control register (PCRC or PCRD) bits. For ESSI0, the GPIO
signals are PC[5–0]. For ESSI1, the GPIO signals are PD[5–0]. The corresponding data bits for Port C
GPIOs are PDRC[5–0]. The corresponding data bits for Port D GPIOs are PDRD[5–0].
= Reserved. Read as zero. Write with zero for future compatibility.
DSP56321 Reference Manual, Rev. 1
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Freescale Semiconductor
Serial Communication Interface
9
The DSP56321 serial communication interface (SCI) provides a full-duplex port for serial
communication with other DSPs, microprocessors, or peripherals such as modems. The SCI
interfaces without additional logic to peripherals that use TTL-level signals. With a small amount
of additional logic, the SCI can connect to peripheral interfaces that have non-TTL level signals,
such as RS-232, RS-422, and so on. This interface uses three dedicated signals: transmit data,
receive data, and SCI serial clock. It supports industry-standard asynchronous bit rates and
protocols, as well as high-speed synchronous data transmission. SCI asynchronous protocols
include a multi-drop mode for master/slave operation with wake-up on idle line and wake-up on
address bit capability. This mode allows the DSP56321 to share a single serial line efficiently
with other peripherals.
The SCI consists of separate transmit and receive sections that can operate asynchronously with
respect to each other. A programmable baud rate generator supplies the transmit and receive
clocks. An enable vector and an interrupt vector are included so that the baud-rate generator can
function as a general-purpose timer when the SCI is not using it, or when the interrupt timing is
the same as that used by the SCI.
9.1 Operating Modes
The operating modes for the DSP56321 SCI are as follows:
„
„
„
„
„
8-bit synchronous (shift register mode)
10-bit asynchronous (1 start, 8 data, 1 stop)
11-bit asynchronous (1 start, 8 data, 1 even parity, 1 stop)
11-bit asynchronous (1 start, 8 data, 1 odd parity, 1 stop)
11-bit multi-drop asynchronous (1 start, 8 data, 1 data type, 1 stop)
This mode is used for master/slave operation with wake-up on idle line and wake-up on
address bit capability. It allows the DSP56321 to share a single serial line efficiently with
other peripherals.
These modes are selected by the SCR WD[2–0] bits. Synchronous data mode is essentially a
high-speed shift register for I/O expansion and stream-mode channel interfaces. A gated transmit
and receive clock compatible with the Intel 8051 serial interface mode 0 synchronizes data.
Asynchronous modes are compatible with most UART-type serial devices. Standard RS-232
communication links are supported by these modes. Multi-drop Asynchronous mode is
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-1
Serial Communication Interface
compatible with the MC68681 DUART, the M68HC11 SCI interface, and the Intel 8051 serial
interface.
9.1.1 Synchronous Mode
Synchronous mode (SCR[WD2–0]=000, Shift Register mode) handles serial-to-parallel and
parallel-to-serial conversions. In Synchronous mode, the clock is always common to the transmit
and receive shift registers. As a controller (synchronous master), the DSP puts out a clock on the
SCLK pin. To select master mode, choose the internal transmit and receive clocks (set TCM and
RCM=0).
As a peripheral (synchronous slave), the DSP accepts an input clock from the SCLK pin. To select
the slave mode, choose the external transmit and receive clocks (TCM and RCM=1). Since there
is no frame signal, if a clock is missed because of noise or any other reason, the receiver loses
synchronization with the data without any error signal being generated. You can detect an error
of this type with an error detecting protocol or with external circuitry such as a watchdog timer.
The simplest way to recover synchronization is to reset the SCI.
9.1.2 Asynchronous Mode
Asynchronous data uses a data format with embedded word sync, which allows an
unsynchronized data clock to be synchronized with the word if the clock rate and number of bits
per word is known. Thus, the clock can be generated by the receiver rather than requiring a
separate clock signal. The transmitter and receiver both use an internal clock that is 16 times the
data rate to allow the SCI to synchronize the data. The data format requires that each data byte
have an additional start bit and stop bit. Also, two of the word formats have a parity bit. The
Multi-drop mode used when SCIs are on a common bus has an additional data type bit. The SCI
can operate in full-duplex or half-duplex modes since the transmitter and receiver are
independent.
9.1.3 Multi-Drop Mode
Multi-drop is a special case of asynchronous data transfer. The key difference is that a protocol
allows networking transmitters and receivers on a single data-transmission line. Inter-processor
messages in a multi-drop network typically begin with a destination address. All receivers check
for an address match at the start of each message. Receivers with no address match can ignore the
remainder of the message and use a wake-up mode to enable the receiver at the start of the next
message. Receivers with an address match can receive the message and optionally transmit an
acknowledgment to the sender. The particular message format and protocol used are determined
by the user’s software.
DSP56321 Reference Manual, Rev. 1
9-2
Freescale Semiconductor
I/O Signals
9.1.3.1 Transmitting Data and Address Characters
To send data, the 8-bit data character must be written to the STX register. Writing the data
character to the STX register sets the ninth bit in the frame to zero, which indicates that this frame
contains data. To send an 8-bit address, the address data is written to the STXA register, and the
ninth bit in the frame is set to one, indicating that this frame contains an address.
9.1.3.2 Wired-OR Mode
Building a multi-drop bus network requires connecting multiple transmitters to a common wire.
The Wired-OR mode allows this to be done without damaging the transmitters when the
transmitters are not in use. A protocol is still needed to prevent two transmitters from
simultaneously driving the bus. The SCI multi-drop word format provides an address field to
support this protocol.
9.1.3.3 Idle Line Wake-up
A wake-up mode frees a DSP from reading messages intended for other processors. The usual
operational procedure is for each DSP to suspend SCI reception (the DSP can continue
processing) until the beginning of a message. Each DSP compares the address in the message
header with the DSP address. If the addresses do not match, the SCI again suspends reception
until the next address. If the address matches, the DSP reads and processes the message and then
suspends reception until the next address. The Idle Line Wake-up mode wakes up the SCI to read
a message before the first character arrives.
9.1.3.4 Address Mode Wake-up
The purpose and basic operational procedure for Address Mode Wake-up is the same as for Idle
Line Wake-up. The difference is that Address Mode Wake-up re-enables the SCI when the ninth
bit in a character is set to one (if cleared, this bit marks a character as data; if set, an address). As
a result, an idle line is not needed, which eliminates the dead time between messages.
9.2 I/O Signals
Each of the three SCI signals (RXD, TXD, and SCLK) can be configured as either a GPIO signal or
as a specific SCI signal. Each signal is independent of the others. For example, if only the TXD
signal is needed, the RXD and SCLK signals can be programmed for GPIO. However, at least one
of the three signals must be selected as an SCI signal to release the SCI from reset.
To enable SCI interrupts, program the SCI control registers before any of the SCI signals are
programmed as SCI functions. In this case, only one transmit interrupt can be generated because
the Transmit Data Register is empty. The timer and timer interrupt operate regardless of how the
SCI pins are configured, either as SCI or GPIO.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-3
Serial Communication Interface
9.2.1 Receive Data (RXD)
This input signal receives byte-oriented serial data and transfers the data to the SCI receive shift
register. Asynchronous input data is sampled on the positive edge of the receive clock (1 × SCLK)
if the SCI Clock Polarity (SCKP) bit is cleared. RXD can be configured as a GPIO signal (PE0)
when the SCI RXD function is not in use.
9.2.2 Transmit Data (TXD)
This output signal transmits serial data from the SCI transmit shift register. Data changes on the
negative edge of the asynchronous transmit clock (SCLK) if SCKP is cleared. This output is stable
on the positive edge of the transmit clock. TXD can be programmed as a GPIO signal (PE1) when
the SCI TXD function is not in use.
9.2.3 SCI Serial Clock (SCLK)
SCLK is a bidirectional signal that provides an input or output clock from which the transmit
and/or receive baud rate is derived in Asynchronous mode and from which data is transferred in
Synchronous mode. SCLK can be programmed as a GPIO signal (PE2) when the SCI SCLK
function is not in use. This signal can be programmed as PE2 when data is transmitted on TXD,
since the clock does not need to be transmitted in Asynchronous mode. Because SCLK is
independent of SCI data I/O, there is no connection between programming the PE2 signal as SCLK
and data coming out the TXD signal.
9.3 SCI After Reset
There are several different ways to reset the SCI:
„
„
„
„
Hardware RESET signal.
Software RESET instruction. Both hardware and software resets clear the port control
register bits, which configure all I/O as GPIO input. The SCI remains in the Reset state as
long as all SCI signals are programmed as GPIO (PC2, PC1, and PC0 all are cleared); the
SCI becomes active only when at least one of the SCI I/O signals is not programmed as
GPIO.
Individual reset. During program execution, the PC2, PC1, and PC0 bits can all be cleared
(that is, individually reset), causing the SCI to stop serial activity and enter the Reset state.
All SCI status bits are set to their reset state. However, the contents of the SCR remain
unaffected so the DSP program can reset the SCI separately from the other internal
peripherals. During individual reset, internal DMA accesses to the data registers of the
SCI are not valid, and the data is unknown.
Stop processing state reset (that is, the STOP instruction). Executing the STOP instruction
halts operation of the SCI until the DSP is restarted, causing the SCI Status Register (SSR)
to be reset. No other SCI registers are affected by the STOP instruction.
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9-4
Freescale Semiconductor
SCI After Reset
Table 9-1 illustrates how each type of reset affects each register in the SCI.
Table 9-1. SCI Registers After Reset
Reset Type
Register
Bit Mnemonic
SCR
Bit Number
HW Reset
SW Reset
IR Reset
ST Reset
REIE
16
0
0
—
—
SCKP
15
0
0
—
—
STIR
14
0
0
—
—
TMIE
13
0
0
—
—
TIE
12
0
0
—
—
RIE
11
0
0
—
—
ILIE
10
0
0
—
—
TE
9
0
0
—
—
RE
8
0
0
—
—
WOMS
7
0
0
—
—
RWU
6
0
0
—
—
WAKE
5
0
0
—
—
SBK
4
0
0
—
—
SSFTD
3
0
0
—
—
WDS[2–0]
2–0
0
0
—
—
R8
FE
PE
OR
IDLE
RDRF
TDRE
TRNE
7
6
5
4
3
2
1
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
1
1
0
0
0
0
0
0
1
1
0
0
0
0
0
0
1
1
TCM
15
0
0
—
—
RCM
14
0
0
—
—
SCP
13
0
0
—
—
COD
12
0
0
—
—
CD[11–0]
11–0
0
0
—
—
SRX
SRX[23–0]
23–16, 15–8, 7–0
—
—
—
—
STX
STX[23–0]
23–0
—
—
—
—
SRSH
SRS[8–0]
8–0
—
—
—
—
SSR
SCCR
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-5
Serial Communication Interface
Table 9-1. SCI Registers After Reset (Continued)
Reset Type
Register
STSH
SRSH
HW
SW
IR
ST
1
0
—
Bit Mnemonic
STS[8–0]
Bit Number
HW Reset
SW Reset
IR Reset
ST Reset
—
—
—
–
8–0
SCI receive shift register, STSH—SCI transmit shift register
Hardware reset is caused by asserting the external RESET signal.
Software reset is caused by executing the RESET instruction.
Individual reset is caused by clearing PCRE (bits 0–2) (configured for GPIO).
Stop reset is caused by executing the STOP instruction.
The bit is set during this reset.
The bit is cleared during this reset.
The bit is not changed during this reset.
9.4 SCI Initialization
The SCI is initialized as follows:
1.
Ensure that the SCI is in its individual reset state (PCRE = $0). Use a hardware RESET
signal or software RESET instruction.
2.
Program the SCI control registers.
3.
Configure at least one SCI signal as an SCI signal.
If interrupts are to be used, the signals must be selected, and global interrupts must be enabled
and unmasked before the SCI can operate. The order does not matter; any one of these three
requirements for interrupts can enable the SCI, but the interrupts should be unmasked last (that is,
I[1–0] bits in the Status Register (SR) should be changed last). Synchronous applications usually
require exact frequencies, so the crystal frequency must be chosen carefully. An alternative to
selecting the system clock to accommodate the SCI requirements is to provide an external clock
to the SCI. When the SCI is configured in Synchronous mode, internal clock, and all the SCI pins
are simultaneously enabled, an extra pulse of one DSP clock length is provided on the SCLK pin.
There are two workarounds for this issue:
„
„
Enable an SCI pin other than SCLK.
In the next instruction, enable the remaining SCI pins, including the SCLK pin.
Following is an example of one way to initialize the SCI:
1.
Ensure that the SCI is in its individual reset state (PCRE = $0).
2.
Configure the control registers (SCR, SCCR) according to the operating mode, but do
not enable transmitter (TE = 0) or receiver (RE = 0).
You can now set the interrupt enable bits that are used during the operation. No interrupt
occurs yet.
DSP56321 Reference Manual, Rev. 1
9-6
Freescale Semiconductor
SCI Initialization
3.
Enable the SCI by setting the PCRE bits according to which signals are used during
operation.
4.
If transmit interrupt is not used, write data to the transmitter.
If transmitter interrupt enable is set, an interrupt is issued and the interrupt handler
should write data into the transmitter. The DMA channel services the SCI transmit
request if it is programmed to service the SCI transmitter.
5.
Enable transmitters (TE = 1) and receiver (RE = 1) according to use.
Operation starts as follows:
„
„
„
For an internally-generated clock, the SCLK signal starts operation immediately after the
SCI is enabled (Step 3 above) for Asynchronous modes. In Synchronous mode, the SCLK
signal is active only while transmitting (that is, a gated clock).
Data is received only when the receiver is enabled (RE = 1) and after the occurrence of the
SCI receive sequence on the RXD signal, as defined by the operating mode (that is, idle line
sequence).
Data is transmitted only after the transmitter is enabled (TE = 1), and after the
initialization sequence has been transmitted (depending on the operating mode).
9.4.1 Preamble, Break, and Data Transmission Priority
Two or three transmission commands can be set simultaneously:
„
„
„
A preamble (TE is set.)
A break (SBK is set or is cleared.)
An indication that there is data for transmission (TDRE is cleared.)
After the current character transmission, if two or more of these commands are set, the
transmitter executes them in the following order: preamble, break, data.
9.4.2 Bootstrap Loading Through the SCI (Boot Mode 2 or A)
When the DSP comes out of reset, it checks the MODD, MODC, MODB, and MODA pins and
sets the corresponding mode bits in the Operating Mode Register (OMR). If the mode bits are
write to 0010 or 1010, respectively, the DSP loads the program RAM from the SCI. Appendix A,
Bootstrap Program shows the complete bootstrap code. This program (1) configures the SCI, (2)
loads the program size, (3) loads the location where the program begins loading in program
memory, and (4) loads the program. First, the SCI Control Register is set to $000302, which
enables the transmitter and receiver and configures the SCI for 10 bits asynchronous with one
start bit, 8 data bits, one stop bit, and no parity. Next, the SCI Clock Control Register is set to
$00C000, which configures the SCI to use external receive and transmit clocks from the SCLK pin
input. This external clock must be 16 times the desired serial data rate.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-7
Serial Communication Interface
The next step is to receive the program size and then the starting address to load the program.
These two numbers are three bytes each loaded least significant byte first. Each byte is echoed
back as it is received. After both numbers are loaded, the program size is in A0 and the starting
address is in A1.
The program is then loaded one byte at a time, least significant byte first. After the program is
loaded, the operating mode is set to zero, the CCR is cleared, and the DSP begins execution with
the first instruction loaded
9.5 Exceptions
The SCI can cause five different exceptions in the DSP, discussed here from the highest to the
lowest priority:
1.
SCI receive data with exception status occurs when the receive data register is full with
a receiver error (parity, framing, or overrun error). To clear the pending interrupt, read
the SCI status register; then read SRX. Use a long interrupt service routine to handle the
error condition. This interrupt is enabled by SCR[16] (REIE).
2.
SCI receive data occurs when the receive data register is full. Read SRX to clear the
pending interrupt. This error-free interrupt can use a fast interrupt service routine for
minimum overhead. This interrupt is enabled by SCR[11] (RIE).
3.
SCI transmit data occurs when the transmit data register is empty. Write STX to clear
the pending interrupt. This error-free interrupt can use a fast interrupt service routine for
minimum overhead. This interrupt is enabled by SCR[12] (TIE).
4.
SCI idle line occurs when the receive line enters the idle state (10 or 11 bits of ones).
This interrupt is latched and then automatically reset when the interrupt is accepted.
This interrupt is enabled by SCR[10] (ILIE).
5.
SCI timer occurs when the baud rate counter reaches zero. This interrupt is
automatically reset when the interrupt is accepted. This interrupt is enabled by SCR[13]
(TMIE).
9.6 SCI Programming Model
The SCI programming model can be viewed as three types of registers:
„
„
„
Control
— SCI Control Register (SCR), page 9-11
— SCI Clock Control Register (SCCR) in page 9-16
Status
— SCI Status Register (SSR) in page 9-14
Data transfer
— SCI Receive Data Registers (SRX) in page 9-20
DSP56321 Reference Manual, Rev. 1
9-8
Freescale Semiconductor
SCI Programming Model
— SCI Transmit Data Registers (STX) in Figure 9-1
— SCI Transmit Data Address Register (STXA) in Figure 9-1
The SCI includes the GPIO functions described in Section 9.7, GPIO Signals and Registers, on
page 9-22. The next subsections describe the registers and their bits.
Mode 0
0
0
0
8-bit Synchronous Data (Shift Register Mode)
WDS2 WDS1 WDS0
TX
(SSFTD = 1)
D7
D6
D5
D4
D3
D2
D1
D0
One Byte From Shift Register
Mode 2
0
1
0
10-bit Asynchronous (1 Start, 8 Data, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 1)
Start
Bit
D7
D6
D5
D4
D3
D2
D1
D0 or
Data
Type
Stop
Bit
Mode 4
1
0
0
11-bit Asynchronous (1 Start, 8 Data, 1 Even Parity, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 1)
Start
Bit
D7
D6
D5
D4
D3
D2
D1
D0 or
Data
Type
Even
Parity
Stop
Bit
Mode 5
1
0
1
11-bit Asynchronous (1 Start, 8 Data, 1 Odd Parity, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 1)
Start
Bit
D7
D6
D5
D4
D3
D2
D1
D0 or
Data
Type
Odd
Parity
Stop
Bit
Mode 6
1
1
0
11-bit Asynchronous multi-drop (1 Start, 8 Data, 1 Data Type, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 1)
Start
Bit
Data Type: 1 = Address Byte
0 = Data Byte
D7
D6
D5
Notes: 1.
2.
3.
D4
D3
D2
D1
D0
Data
Type
Stop
Bit
Modes 1, 3, and 7 are reserved.
D0 = LSB; D7 = MSB
Data is transmitted and received LSB first if SSFTD = 0, or MSB
first if SSFTD = 1
Figure 9-1. SCI Data Word Formats (SSFTD = 1), 1
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-9
Serial Communication Interface
Mode 0
0
0
0
8-bit Synchronous Data (Shift Register Mode)
WDS2 WDS1 WDS0
TX
(SSFTD = 0)
D0
D1
D2
D3
D4
D5
D6
D7
One Byte From Shift Register
Mode 2
0
1
0
10-bit Asynchronous (1 Start, 8 Data, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 0)
Start
Bit
D0
D1
D2
D3
D4
D5
D6
D7 or
Data
Type
Stop
Bit
Mode 4
1
0
0
11-bit Asynchronous (1 Start, 8 Data, 1 Even Parity, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 0)
Start
Bit
D0
D1
D2
D3
D4
D5
D6
D7 or
Data
Type
Even
Parity
Stop
Bit
Mode 5
1
0
1
11-bit Asynchronous (1 Start, 8 Data, 1 Odd Parity, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 0)
Start
Bit
D0
D1
D2
D3
D4
D5
D6
D7 or
Data
Type
Odd
Parity
Stop
Bit
Mode 6
1
1
0
11-bit Asynchronous multi-drop (1 Start, 8 Data, 1 Data Type, 1 Stop)
WDS2 WDS1 WDS0
TX
(SSFTD = 0)
Start
Bit
D0
Data Type: 1 = Address Byte
0 = Data Byte
D1
D2
D3
Notes: 1.
2.
3.
D4
D5
D6
D7
Data
Type
Stop
Bit
Modes 1, 3, and 7 are reserved.
D0 = LSB; D7 = MSB.
Data is transmitted and received LSB first if SSFTD = 0,
or MSB first if SSFTD = 1.
Figure 9-2. SCI Data Word Formats (SSFTD = 0), 2
DSP56321 Reference Manual, Rev. 1
9-10
Freescale Semiconductor
SCI Programming Model
9.6.1 SCI Control Register (SCR)
The SCR is a read/write register that controls the serial interface operation.
.
23
22
21
20
19
18
17
16
REIE
15
14
13
12
11
10
9
8
SCKP
STIR
TMIE
TIE
RIE
ILIE
TE
RE
7
6
5
4
3
2
1
0
WOMS
RWU
WAKE
SBK
SSFTD
WDS2
WDS1
WDS0
—Reserved bit; read as 0; write to 0 for future compatibility.
Table 9-2. SCI Control Register (SCR) Bit Definitions
Bit
Number
Bit Name
23–17
Reset
Value
Description
0
Reserved. Write to 0 for future compatibility.
16
REIE
0
Receive with Exception Interrupt Enable
Enables/disables the SCI receive data with exception interrupt. If REIE is cleared, the
receive data with exception interrupt is disabled. If both REIE and RDRF are set, and PE,
FE, and OR are not all cleared, the SCI requests an SCI receive data with exception
interrupt from the interrupt controller. Either a hardware RESET signal or a software
RESET instruction clears REIE.
15
SCKP
0
SCI Clock Polarity
Controls the clock polarity sourced or received on the clock signal (SCLK), eliminating the
need for an external inverter. When SCKP is cleared, the clock polarity is positive; when
SCKP is set, the clock polarity is negative. In Synchronous mode, positive polarity means
that the clock is normally positive and transitions negative during valid data. Negative
polarity means that the clock is normally negative and transitions positive during valid
data. In Asynchronous mode, positive polarity means that the rising edge of the clock
occurs in the center of the period that data is valid. Negative polarity means that the falling
edge of the clock occurs during the center of the period that data is valid. Either a
hardware RESET signal or a software RESET instruction clears SCKP.
14
STIR
0
Timer Interrupt Rate
Controls a divide-by-32 in the SCI Timer interrupt generator. When STIR is cleared, the
divide-by-32 is inserted in the chain. When STIR is set, the divide-by-32 is bypassed,
thereby increasing timer resolution by a factor of 32. Either a hardware RESET signal or a
software RESET instruction clears this bit. To ensure proper operation of the timer, STIR
must not be changed during timer operation (that is, if TMIE = 1).
13
TMIE
0
Timer Interrupt Enable
Enables/disables the SCI timer interrupt. If TMIE is set, timer interrupt requests are sent to
the interrupt controller at the rate set by the SCI clock register. The timer interrupt is
automatically cleared by the timer interrupt acknowledge from the interrupt controller. This
feature allows DSP programmers to use the SCI baud rate generator as a simple periodic
interrupt generator if the SCI is not in use, if external clocks are used for the SCI, or if
periodic interrupts are needed at the SCI baud rate. The SCI internal clock is divided by
16 (to match the 1 × SCI baud rate) for timer interrupt generation. This timer does not
require that any SCI signals be configured for SCI use to operate. Either a hardware
RESET signal or a software RESET instruction clears TMIE.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-11
Serial Communication Interface
Table 9-2. SCI Control Register (SCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
12
TIE
0
SCI Transmit Interrupt Enable
Enables/disables the SCI transmit data interrupt. If TIE is cleared, transmit data interrupts
are disabled, and the transmit data register empty (TDRE) bit in the SCI status register
must be polled to determine whether the transmit data register is empty. If both TIE and
TDRE are set, the SCI requests an SCI transmit data interrupt from the interrupt
controller. Either a hardware RESET signal or a software RESET instruction clears TIE.
11
RIE
0
SCI Receive Interrupt Enable
Enables/disables the SCI receive data interrupt. If RIE is cleared, the receive data
interrupt is disabled, and the RDRF bit in the SCI status register must be polled to
determine whether the receive data register is full. If both RIE and RDRF are set, the SCI
requests an SCI receive data interrupt from the interrupt controller. Receive interrupts with
exception have higher priority than normal receive data interrupts. Therefore, if an
exception occurs (that is, if PE, FE, or OR are set) and REIE is set, the SCI requests an
SCI receive data with exception interrupt from the interrupt controller. Either a hardware
RESET signal or a software RESET instruction clears RIE.
10
ILIE
0
Idle Line Interrupt Enable
When ILIE is set, the SCI interrupt occurs when IDLE (SCI status register bit 3) is set.
When ILIE is cleared, the IDLE interrupt is disabled. Either a hardware RESET signal or a
software RESET instruction clears ILIE. An internal flag, the shift register idle interrupt
(SRIINT) flag, is the interrupt request to the interrupt controller. SRIINT is not directly
accessible to the user. When a valid start bit is received, an idle interrupt is generated if
both IDLE and ILIE are set. The idle interrupt acknowledge from the interrupt controller
clears this interrupt request. The idle interrupt is not asserted again until at least one
character has been received. The results are as follows:
• The IDLE bit shows the real status of the receive line at all times.
• An idle interrupt is generated once for each idle state, no matter how long the idle state
lasts.
9
TE
0
Transmitter Enable
When TE is set, the transmitter is enabled. When TE is cleared, the transmitter completes
transmission of data in the SCI transmit data shift register, and then the serial output is
forced high (that is, idle). Data present in the SCI transmit data register (STX) is not
transmitted. STX can be written and TDRE cleared, but the data is not transferred into the
shift register. TE does not inhibit TDRE or transmit interrupts. Either a hardware RESET
signal or a software RESET instruction clears TE.
Description
Setting TE causes the transmitter to send a preamble of 10 or 11 consecutive ones
(depending on WDS), giving you a convenient way to ensure that the line goes idle before
a new message starts. To force this separation of messages by the minimum idle line
time, we recommend the following sequence:
1. Write the last byte of the first message to STX.
2.
Wait for TDRE to go high, indicating the last byte has been transferred to the
transmit shift register.
3.
Clear TE and set TE to queue an idle line preamble to follow immediately the
transmission of the last character of the message (including the stop bit).
4.
Write the first byte of the second message to STX.
In this sequence, if the first byte of the second message is not transferred to STX prior to
the finish of the preamble transmission, the transmit data line remains idle until STX is
finally written.
DSP56321 Reference Manual, Rev. 1
9-12
Freescale Semiconductor
SCI Programming Model
Table 9-2. SCI Control Register (SCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
8
RE
0
Receiver Enable
When RE is set, the receiver is enabled. When RE is cleared, the receiver is disabled, and
data transfer from the receive shift register to the receive data register (SRX) is inhibited.
If RE is cleared while a character is being received, the reception of the character
completes before the receiver is disabled. RE does not inhibit RDRF or receive interrupts.
Either a hardware RESET signal or a software RESET instruction clears RE.
7
WOMS
0
Wired-OR Mode Select
When WOMS is set, the SCI TXD driver is programmed to function as an open-drain
output and can be wired together with other TXD signals in an appropriate bus
configuration, such as a master-slave multi-drop configuration. An external pull-up resistor
is required on the bus. When WOMS is cleared, the TXD signal uses an active internal
pull-up. Either a hardware RESET signal or a software RESET instruction clears WOMS.
6
RWU
0
Receiver Wake-up Enable
When RWU is set and the SCI is in Asynchronous mode, the wake-up function is enabled;
that is, the SCI is asleep and can be awakened by the event defined by the WAKE bit. In
Sleep state, all interrupts and all receive flags except IDLE are disabled. When the
receiver wakes up, RWU is cleared by the wake-up hardware. You can also clear the
RWU bit to wake up the receiver. You can use RWU to ignore messages that are for other
devices on a multi-drop serial network. Wake up on idle line (WAKE is cleared) or wake up
on address bit (WAKE is set) must be chosen. When WAKE is cleared and RWU is set,
the receiver does not respond to data on the data line until an idle line is detected. When
WAKE is set and RWU is set, the receiver does not respond to data on the data line until
a data frame with Bit 9 set is detected.
Description
When the receiver wakes up, the RWU bit is cleared, and the first frame of data is
received. If interrupts are enabled, the CPU is interrupted and the interrupt routine reads
the message header to determine whether the message is intended for this DSP. If the
message is for this DSP, the message is received, and RWU is set to wait for the next
message. If the message is not for this DSP, the DSP immediately sets RWU. Setting
RWU causes the DSP to ignore the remainder of the message and wait for the next
message. Either a hardware RESET signal or a software RESET instruction clears RWU.
RWU is ignored in Synchronous mode.
5
WAKE
0
Wake-up Mode Select
When WAKE is cleared, the wake up on Idle Line mode is selected and the SCI receiver is
re-enabled by an idle string of at least 10 or 11 (depending on WDS mode) consecutive
ones. The transmitter software must provide this idle string between consecutive
messages. The idle string cannot occur within a valid message because each word frame
there contains a start bit that is 0. When WAKE is set, the wake up on address bit mode is
selected and the SCI receiver is re-enabled when the last (eighth or ninth) data bit
received in a character (frame) is 1. The ninth data bit is the address bit (R8) in the 11-bit
multi-drop mode; the eighth data bit is the address bit in the 10-bit asynchronous and
11-bit asynchronous with parity modes. Thus, the received character is an address that
has to be processed by all sleeping processors. Each processor must compare the
received character with its own address and determine whether to receive or ignore all
following characters.
4
SBK
0
Send Break
A break is an all-zero word frame—a start bit 0, characters of all zeros (including any
parity), and a stop bit 0 (that is, ten or eleven zeros, depending on the mode selected). If
SBK is set and then cleared, the transmitter finishes transmitting the current frame, sends
10 or 11 0s, and reverts to idle or sending data. If SBK remains set, the transmitter
continually sends whole frames of 0s (10 or 11 bits with no stop bit). At the end of the
break code, the transmitter sends at least one high (set) bit before transmitting any data to
guarantee recognition of a valid start bit. Break can signal an unusual condition, message,
and so on, by forcing a frame error; the frame error is caused by a missing stop bit.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-13
Serial Communication Interface
Table 9-2. SCI Control Register (SCR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
3
SSFTD
0
SCI Shift Direction
Determines the order in which the SCI data shift registers shift data in or out: MSB first
when set, LSB first when cleared. The parity and data type bits do not change their
position in the frame, and they remain adjacent to the stop bit.
2–0
WDS[2–0]
0
Word Select
Select the format of transmitted and received data. Asynchronous modes are compatible
with most UART-type serial devices, and they support standard RS-232 communication
links. Multi-drop Asynchronous mode is compatible with the MC68681 DUART, the
M68HC11 SCI interface, and the Intel 8051 serial interface. Synchronous data mode is
essentially a high-speed shift register for I/O expansion and stream-mode channel
interfaces. You can synchronize data by using a gated transmit and receive clock
compatible with the Intel 8051 serial interface mode 0. When odd parity is selected, the
transmitter counts the number of ones in the data word. If the total is not an odd number,
the parity bit is set, thus producing an odd number. If the receiver counts an even number
of ones, an error in transmission has occurred. When even parity is selected, an even
number must result from the calculation performed at both ends of the line, or an error in
transmission has occurred.
Description
WDS2
WDS1
WDS0
Mode
Word Formats
0
0
0
0
8-Bit Synchronous Data (shift register mode)
0
0
1
1
Reserved
0
1
0
2
10-Bit Asynchronous (1 start, 8 data, 1 stop)
1
1
1
3
Reserved
1
0
0
4
11-Bit Asynchronous
(1 start, 8 data, 1 even parity, 1 stop)
1
0
1
5
11-Bit Asynchronous
(1 start, 8 data, 1 odd parity, 1 stop)
1
1
0
6
11-Bit Multi-drop Asynchronous
(1 start, 8 data, 1 data type, 1 stop)
0
1
1
7
Reserved
9.6.2 SCI Status Register (SSR)
The SSR is a read-only register that indicates the status of the SCI.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R8
FE
PE
OR
IDLE
RDRF
TDRE
TRNE
—Reserved bit; read as 0; write to 0 for future compatibility.
DSP56321 Reference Manual, Rev. 1
9-14
Freescale Semiconductor
SCI Programming Model
Table 9-3. SCI Status Register (SSR) Bit Definitions
Bit
Number
Bit Name
23–8
Reset
Value
Description
0
Reserved. Write to 0 for future compatibility.
7
R8
0
Received Bit 8
In 11-bit Asynchronous Multi-drop mode, the R8 bit indicates whether the received byte
is an address or data. R8 is set for addresses and is cleared for data. R8 is not affected
by reads of the SRX or SCI status register. A hardware RESET signal, a software
RESET instruction, an SCI individual reset, or a STOP instruction clears R8.
6
FE
0
Framing Error Flag
In Asynchronous mode, FE is set when no stop bit is detected in the data string
received. FE and RDRE are set simultaneously when the received word is transferred
to the SRX. However, the FE flag inhibits further transfer of data into the SRX until it is
cleared. FE is cleared when the SCI status register is read followed by a read of the
SRX. A hardware RESET signal, a software RESET instruction, an SCI individual reset,
or a STOP instruction clears FE. In 8-bit Synchronous mode, FE is always cleared. If
the byte received causes both framing and overrun errors, the SCI receiver recognizes
only the overrun error.
5
PE
0
Parity Error
In 11-bit Asynchronous modes, PE is set when an incorrect parity bit is detected in the
received character. PE and RDRF are set simultaneously when the received word is
transferred to the SRX. If PE is set, further data transfer into the SRX is not inhibited.
PE is cleared when the SCI status register is read, followed by a read of SRX. A
hardware RESET signal, a software RESET instruction, an SCI individual reset, or a
STOP instruction also clears PE. In 10-bit Asynchronous mode, 11-bit multi-drop mode,
and 8-bit Synchronous mode, the PE bit is always cleared since there is no parity bit in
these modes. If the byte received causes both parity and overrun errors, the SCI
receiver recognizes only the overrun error.
4
OR
0
Overrun Error Flag
Set when a byte is ready to be transferred from the receive shift register to the receive
data register (SRX) that is already full (RDRF = 1). The receive shift register data is not
transferred to the SRX. The OR flag indicates that character(s) in the received data
stream may have been lost. The only valid data is located in the SRX. OR is cleared
when the SCI status register is read, followed by a read of SRX. The OR bit clears the
FE and PE bits; that is, overrun error has higher priority than FE or PE. A hardware
RESET signal, a software RESET instruction, an SCI individual reset, or a STOP
instruction clears OR.
3
IDLE
0
Idle Line Flag
Set when 10 (or 11) consecutive ones are received. IDLE is cleared by a start-bit
detection. The IDLE status bit represents the status of the receive line. The transition of
IDLE from 0 to 1 can cause an IDLE interrupt (ILIE).
2
RDRF
0
Receive Data Register Full
Set when a valid character is transferred to the SCI receive data register from the SCI
receive shift register (regardless of the error bits condition). RDRF is cleared when the
SCI receive data register is read.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-15
Serial Communication Interface
Table 9-3. SCI Status Register (SSR) Bit Definitions (Continued)
Bit
Number
Bit Name
Reset
Value
1
TDRE
1
Description
Transmit Data Register Empty
Set when the SCI transmit data register is empty. When TDRE is set, new data can be
written to one of the SCI transmit data registers (STX) or the transmit data address
register (STXA). TDRE is cleared when the SCI transmit data register is written. Either
a hardware RESET signal, a software RESET instruction, an SCI individual reset, or a
STOP instruction sets TDRE.
In Synchronous mode, when the internal SCI clock is in use, there is a delay of up to
5.5 serial clock cycles between the time that STX is written until TDRE is set, indicating
the data has been transferred from the STX to the transmit shift register. There is a
delay of 2 to 4 serial clock cycles between writing STX and loading the transmit shift
register; in addition, TDRE is set in the middle of transmitting the second bit. When
using an external serial transmit clock, if the clock stops, the SCI transmitter stops.
TDRE is not set until the middle of the second bit transmitted after the external clock
starts. Gating the external clock off after the first bit has been transmitted delays TDRE
indefinitely.
In Asynchronous mode, the TDRE flag is not set immediately after a word is transferred
from the STX or STXA to the transmit shift register nor when the word first begins to be
shifted out. TDRE is set 2 cycles (of the 16 × clock) after the start bit; that is, 2 (16 ×
clock) cycles into the transmission time of the first data bit.
0
TRNE
1
Transmitter Empty
This flag bit is set when both the transmit shift register and transmit data register (STX)
are empty, indicating that there is no data in the transmitter. When TRNE is set, data
written to one of the three STX locations or to the transmit data address register (STXA)
is transferred to the transmit shift register and is the first data transmitted. TRNE is
cleared when a write into STX or STXA clears TDRE or when an idle, preamble, or
break is transmitted. When set, TRNE indicates that the transmitter is empty; therefore,
the data written to STX or STXA is transmitted next. That is, there is no word in the
transmit shift register being transmitted. This procedure is useful when initiating the
transfer of a message (that is, a string of characters).
9.6.3 SCI Clock Control Register (SCCR)
The SCCR is a read/write register that controls the selection of clock modes and baud rates for
the transmit and receive sections of the SCI interface. The SCCR is cleared by a hardware RESET
signal.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
TCM
RCM
SCP
COD
CD11
CD10
CD9
CD8
7
6
5
4
3
2
1
0
CD7
CD6
CD5
CD4
CD3
CD2
CD1
CD0
Reserved. Read as 0. Write to 0 for future compatibility.
DSP56321 Reference Manual, Rev. 1
9-16
Freescale Semiconductor
SCI Programming Model
Table 9-4. SCI Clock Control Register (SCCR) Bit Definitions
Bit
Number
Bit
Name
Reset
Value
23–16
Description
0
Reserved. Write to 0 for future compatibility.
15
TCM
0
Transmit Clock Source
Selects whether an internal or external clock is used for the transmitter. If TCM is cleared,
the internal clock is used. If TCM is set, the external clock (from the SCLK signal) is used.
14
RCM
0
Receive Clock Mode Source
Selects whether an internal or external clock is used for the receiver. If RCM is cleared, the
internal clock is used. If RCM is set, the external clock (from the SCLK signal) is used.
TCM
RCM
TX Clock
RX Clock
SCLK
Mode
0
0
Internal
Internal
Output
Synchronous/asynchronous
0
1
Internal
External
Input
Asynchronous only
1
0
External
Internal
Input
Asynchronous only
1
1
External
External
Input
Synchronous/asynchronous
13
SCP
0
Clock Prescaler
Selects a divide by 1 (SCP is cleared) or divide by 8 (SCP is set) prescaler for the clock
divider. The output of the prescaler is further divided by 2 to form the SCI clock.
12
COD
0
Clock Out Divider
The clock output divider is controlled by COD and the SCI mode. If the SCI mode is
synchronous, the output divider is fixed at divide by 2. If the SCI mode is asynchronous,
either:
• If COD is cleared and SCLK is an output (that is, TCM and RCM are both cleared), then
the SCI clock is divided by 16 before being output to the SCLK signal. Thus, the SCLK
output is a 1 × clock.
• If COD is set and SCLK is an output, the SCI clock is fed directly out to the SCLK signal.
Thus, the SCLK output is a 16 × baud clock.
11–0
CD[11–
0]
0
Clock Divider
Specifies the divide ratio of the prescale divider in the SCI clock generator. A divide ratio
from 1 to 4096 (CD[11–0] = $000 to $FFF) can be selected.
The SCI clock determines the data transmission (baud) rate and can also establish a periodic
interrupt that can act as an event timer or be used in any other timing function. Bits CD11– CD0,
SCP, and SCR[STIR] work together to determine the time base. If SCR[TMIE] = 1 when the
periodic time-out occurs, the SCI timer interrupt is recognized and pending. The SCI timer
interrupt is automatically cleared when the interrupt is serviced. This interrupt occurs every time
the periodic timer times out.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-17
Serial Communication Interface
Figure 9-3 shows the block diagram of the internal clock generation circuitry with the formula to
compute the bit rate when the internal clock is used.
Fcore
Divide
By 2
12-bit Counter
CD[11–0]
Prescaler:
Divide by
1 or 8
Divide
By 2
SCP
Internal Clock
Divide
by 16
SCI Core Logic
Uses Divide by 16 for
Asynchronous
Uses Divide by 2 for
Synchronous
STIR
COD
If Asynchronous
Divide by 1 or 16
If Synchronous
Divide By 2
SCKP
SCKP = 0 +
SCKP = 1 -
Timer
Interrupt
(STMINT)
Fcore
bps = 64 × (7(SCP) + 1) × CD + 1)
where: SCP = 0 or 1
CD = $000 to $FFF
SCLK
Figure 9-3. SCI Baud Rate Generator
As noted in Section 9.6.1, the SCI can be configured to operate in a single Synchronous mode or
one of five Asynchronous modes. Synchronous mode requires that the TX and RX clocks use the
same source, but that source may be the internal SCI clock if the SCI is configured as a master
device or an external clock if the SCI is configured as a slave device. Asynchronous modes may
use clocks from the same source (internal or external) or different sources for the TX clock and
the RX clock.
For synchronous operation, the SCI uses a clock that is equal to the two times the desired bit rate
(designated as the 2 × clock) for both internal and external clock sources. It must use the same
source for both the TX and RX clock. The internal clock is used if the SCI is the master device
and the external clock is used if the SCI is the slave device, as noted above. The clock is gated
and limited to a maximum frequency equal to one eighth of the DSP core operating frequency
(that is, 12.5 MHz for a DSP core frequency of 100 MHz).
For asynchronous operation, the SCI can use the internal and external clocks in any combination
as the source clocks for the TX clock and RX clock. If an external clock is used for the SCLK
input, it must be sixteen times the desired bit rate (designated as the 16 × clock), as indicated in
DSP56321 Reference Manual, Rev. 1
9-18
Freescale Semiconductor
SCI Programming Model
Figure 9-4. When the internal clock is used to supply a clock to an external device, the clock can
use the actual bit rate (designated as the 1 × clock) or the 16 × clock rate, as determined by the
COD bit. The output clock is continuous.
Select 8-or 9-bit Words
0
Idle Line
1
2
3
4
5
6
7
8
RX, TX Data
(SSFTD = 0)
Start
Stop
Start
x1 Clock
x16 Clock
(SCKP = 0)
Figure 9-4. 16 x Serial Clock
When SCKP is cleared, the transmitted data on the TXD signal changes on the negative edge of
the serial clock and is stable on the positive edge. When SCKP is set, the data changes on the
positive edge and is stable on the negative edge. The received data on the RXD signal is sampled
on the positive edge (if SCKP = 0) or on the negative edge (if SCKP = 1) of the serial clock.
9.6.4 SCI Data Registers
The SCI data registers are divided into two groups: receive and transmit, as shown in Figure 9-1.
There are two receive registers: a Receive Data Register (SRX) and a serial-to-parallel Receive
Shift Register. There are also two transmit registers: a Transmit Data Register (called either STX
or STXA) and a parallel-to-serial Transmit Shift Register.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-19
Serial Communication Interface
23
16 15
8 7
0
SCI Receive Data Register High (Read Only)
SRX
SRX
SCI Receive Data Register Middle (Read Only)
SRX
SCI Receive Data Register Low (Read Only)
SCI Receive Data Shift Register
RXD
Note: SRX is the same register decoded at three different addresses.
(a) Receive Data Register
23
16 15
8 7
0
STX
SCI Transmit Data Register High (Write Only)
STX
SCI Transmit Data Register Middle (Write Only)
SCI Transmit Data Register Low (Write Only)
STX
SCI Transmit Data Shift Register
23
16 15
TXD
8 7
0
STXA
Notes: 1.
2.
SCI Transmit Data Address Register (Write Only)
Bytes are masked on the fly.
STX is the same register decoded at four different addresses.
(b) Transmit Data Register
Figure 9-5. SCI Programming Model—Data Registers
9.6.4.1 SCI Receive Register (SRX)
Data bits received on the RXD signal are shifted into the SCI receive shift register. When a
complete word is received, the data portion of the word is transferred to the byte-wide SRX. This
process converts serial data to parallel data and provides double buffering. Double buffering
promotes flexibility and increased throughput since the programmer can save (and process) the
previous word while the current word is being received.
The SRX can be read at three locations as SRXL, SRXM, and SRXH. When SRXL is read, the
contents of the SRX are placed in the lower byte of the data bus and the remaining bits on the
data bus are read as zeros. Similarly, when SRXM is read, the contents of SRX are placed into the
middle byte of the bus, and when SRXH is read, the contents of SRX are placed into the high
byte with the remaining bits are read as 0s. This way of mapping SRX efficiently packs three
bytes into one 24-bit word by ORing three data bytes read from the three addresses.
The SCR WDS0, WDS1, and WDS2 control bits define the length and format of the serial word.
The SCR receive clock mode (RCM) defines the clock source.
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9-20
Freescale Semiconductor
SCI Programming Model
In Asynchronous mode, the start bit, the eight data bits, the address/data indicator bit or the parity
bit, and the stop bit are received, respectively. Data bits are sent LSB first if SSFTD is cleared,
and MSB first if SSFTD is set. In Synchronous mode, a gated clock provides synchronization. In
either Synchronous or Asynchronous mode, when a complete word is clocked in, the contents of
the shift register can be transferred to the SRX and the flags; RDRF, FE, PE, and OR are changed
appropriately. Because the operation of the receive shift register is transparent to the DSP, the
contents of this register are not directly accessible to the programmer.
9.6.4.2 SCI Transmit Register (STX)
The transmit data register is a one-byte-wide register mapped into four addresses as STXL,
STXM, STXH, and STXA. In Asynchronous mode, when data is to be transmitted, STXL,
STXM, and STXH are used. When STXL is written, the low byte on the data bus is transferred to
the STX. When STXM is written, the middle byte is transferred to the STX. When STXH is
written, the high byte is transferred to the STX. This structure makes it easy for the programmer
to unpack the bytes in a 24-bit word for transmission. TDXA should be written in 11-bit
asynchronous multi-drop mode when the data is an address and the programmer wants to set the
ninth bit (the address bit). When STXA is written, the data from the low byte on the data bus is
stored in it. The address data bit is cleared in 11-bit asynchronous multi-drop mode when any of
STXL, STXM, or STXH is written. When either STX (STXL, STXM, or STXH) or STXA is
written, TDRE is cleared.
The transfer from either STX or STXA to the transmit shift register occurs automatically, but not
immediately, after the last bit from the previous word is shifted out; that is, the transmit shift
register is empty. Like the receiver, the transmitter is double-buffered. However, a delay of two
to four serial clock cycles occurs between when the data is transferred from either STX or STXA
to the transmit shift register and when the first bit appears on the TXD signal. (A serial clock cycle
is the time required to transmit one data bit.)
The transmit shift register is not directly addressable, and there is no dedicated flag for this
register. Because of this fact and the two- to four-cycle delay, two bytes cannot be written
consecutively to STX or STXA without polling, because the second byte might overwrite the first
byte. Thus, you should always poll the TDRE flag prior to writing STX or STXA to prevent
overruns unless transmit interrupts are enabled. Either STX or STXA is usually written as part of
the interrupt service routine. An interrupt is generated only if TDRE is set. The transmit shift
register is indirectly visible via the SSR[TRNE] bit.
In Synchronous mode, data is synchronized with the transmit clock. That clock can have either an
internal or external source, as defined by the TCM bit in the SCCR. The length and format of the
serial word is defined by the WDS0, WDS1, and WDS2 control bits in the SCR. In
Asynchronous mode, the start bit, the eight data bits (with the LSB first if SSFTD = 0 and the
MSB first if SSFTD = 1), the address/data indicator bit or parity bit, and the stop bit are
transmitted in that order. The data to be transmitted can be written to any one of the three STX
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-21
Serial Communication Interface
addresses. If SCKP is set and SSHTD is set, SCI Synchronous mode is equivalent to the SSI
operation in 8-bit data on-demand mode.
When data is written to a peripheral device, there is a two-cycle pipeline delay until any status
bits affected by this operation are updated. If you read any of those status bits within the next two
cycles, the bit does not reflect its current status. For details see the DSP56300 Family Manual.
9.7 GPIO Signals and Registers
Three registers control the GPIO functionality of the SCI pins: Port E control register (PCRE),
Port E direction register (PRRE) and Port E data register (PDRE).
9.7.1 Port E Control Register (PCRE)
The read/write PCRE controls the functionality of SCI GPIO signals. Each of the PCRE[2–0] bits
controls the functionality of the corresponding port signal. When a PCRE[i] bit is set, the
corresponding port signal is configured as an SCI signal. When a PC[i] bit is cleared, the
corresponding port signal is configured as a GPIO signal. A hardware RESET signal or a software
RESET instruction clears all PCRE bits.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PE2/
SCLK
PE1/
TXD
PE0/
RXD
Note:
For bits 2–0, a 0 selects PEn as the signal and a 1 selects the specified SCI signal.
= Reserved. Read as zero. Write to zero for future compatibility.
9.7.2 Port E Direction Register (PRRE)
The read/write PRRE controls the direction of SCI GPIO signals. When port signal[i] is
configured as GPIO, PRRE[i] controls the port signal direction. When PRRE[i] is set, the GPIO
port signal[i] is configured as output. When PRRE[i] is cleared, the GPIO port signal[i] is
configured as input. A hardware RESET signal or a software RESET instruction clears all PRRE
bits
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9-22
Freescale Semiconductor
GPIO Signals and Registers
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PRRE2
PRRE1
PRRE0
Note:
For bits 2–0, a 0 configures PEn as a GPI and a 1 configures PEn as a GPO. For the SCI, the GPIO signals are
PE[2–0]. The corresponding direction bits for Port E GPIOs are PRRE[2–0].
= Reserved. Read as zero. Write with zero for future compatibility.
9.7.3 Port E Data Register (PDRE)
Bits 2–0 of the read/write 24-bit PDRE writes data to or reads data from the associated SCI signal
lines when configured as GPIO signals. If a port signal PE[i] is configured as an input (GPI), the
corresponding PDRE[i] bit reflects the value present on the input signal line. If a port signal PE[i]
is configured as an output (GPO), a value written to the corresponding PDRE[i] bit is reflected as
a value on the output signal line. Either a hardware RESET signal or a software RESET
instruction clears all PDR bits.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PDRE2
PDRE1
PDRE0
Note:
For bits 2–0, the value represents the level that is written to or read from the associated signal line if enabled as
a GPIO signal by the PCRE bits. For SCI, the GPIO signals are PE[2–0]. The corresponding data bits are
PDRE[2–0].
= Reserved. Read as zero. Write with zero for future compatibility.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
9-23
Serial Communication Interface
DSP56321 Reference Manual, Rev. 1
9-24
Freescale Semiconductor
Triple Timer Module
10
The timers in the DSP56321 internal triple timer module act as timed pulse generators or as
pulse-width modulators. Each timer has a single signal that can function as a GPIO signal or as a
timer signal. Each timer can also function as an event counter to capture an event or to measure
the width or period of a signal.
10.1 Overview
The timer module contains a common 21-bit prescaler and three independent and identical
general-purpose 24-bit timer/event counters, each with its own register set. Each timer has the
following capabilities:
„
„
„
„
Uses internal or external clocking
Interrupts the DSP56321 after a specified number of events (clocks) or signals an external
device after counting internal events
Triggers DMA transfers after a specified number of events (clocks) occurs
Connects to the external world through one bidirectional signal, designated
TIO[0– 2] for timers 0–2.
When TIO is configured as an input, the timer functions as an external event counter or measures
external pulse width/signal period. When TIO is configured as an output, the timer functions as a
timer, a watchdog timer, or a pulse-width modulator. When the timer does not use TIO, it can be
used as a GPIO signal (also called TIO[0–2]).
10.1.1 Triple Timer Module Block Diagram
Figure 10-1 shows a block diagram of the triple timer module. This module includes a 24-bit
Timer Prescaler Load Register (TPLR), a 24-bit Timer Prescaler Count Register (TPCR), and
three timers. Each timer can use the prescaler clock as its clock source.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-1
Triple Timer Module
GDB
24
24
24
TPLR
TPCR
24
Timer Prescaler
Load Register
Timer Prescaler
Count Register
Timer 0
Timer 1
24-bit Counter
Timer 2
CLK/2
TIO0 TIO1 TIO2
Figure 10-1. Triple Timer Module Block Diagram
10.1.2 Individual Timer Block Diagram
Figure 10-2 shows the structure of an individual timer block. The DSP56321 treats each timer as
a memory-mapped peripheral with four registers occupying four 24-bit words in the X data
memory space. The three timers are identical in structure and function. Either standard polled or
interrupt programming techniques can be used to service the timers. A single, generic timer is
discussed in this chapter. Each timer includes the following:
„
„
„
„
„
„
24-bit counter
24-bit read/write Timer Control and Status Register (TCSR)
24-bit read-only Timer Count Register (TCR)
24-bit write-only Timer Load Register (TLR)
24-bit read/write Timer Compare Register (TCPR)
Logic for clock selection and interrupt/DMA trigger generation.
The timer mode is controlled by the TC[3–0] bits which are TCSR[7–4]. For a listing of the timer
modes and descriptions of their operations, see Section 10.3, Operating Modes, on page 10-5.
DSP56321 Reference Manual, Rev. 1
10-2
Freescale Semiconductor
Operation
GDB
24
24
24
TCSR
24
Load
Register
9
Count
Register
Compare
Register
24
24
24
2
24
Timer Control
Logic
TIO
TCPR
TCR
TLR
Control/Status
Register
24
Counter
CLK/2 Prescaler CLK
=
Timer interrupt/DMA request
Figure 10-2. Timer Module Block Diagram
10.2 Operation
This section discusses the following timer basics: reset, initialization, and exceptions.
10.2.1 Timer After Reset
A hardware RESET signal or software RESET instruction clears the Timer Control and Status
Register for each timer, thus configuring each timer as a GPIO. A timer is active only if the timer
enable bit 0 (TCSR[TE]) in the specific timer TCSR is set.
10.2.2 Timer Initialization
To initialize a timer, do the following:
1.
Ensure that the timer is not active either by sending a reset or clearing the TCSR[TE]
bit.
2.
Configure the control register (TCSR) to set the timer operating mode. Set the interrupt
enable bits as needed for the application.
3.
Configure other registers: Timer Prescaler Load Register (TPLR), Timer Load Register
(TLR), and Timer Compare Register (TCPR) as needed for the application.
4.
Enable the timer by setting the TCSR[TE] bit.
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Freescale Semiconductor
10-3
Triple Timer Module
10.2.3 Timer Exceptions
Each timer can generate two different exceptions:
„
„
Timer Overflow (highest priority) — Occurs when the timer counter reaches the overflow
value. This exception sets the TOF bit. TOF is cleared when a value of one is written to it
or when the timer overflow exception is serviced.
Timer Compare (lowest priority) — Occurs when the timer counter reaches the value
given in the Timer Compare Register (TCPR) for all modes except measurement modes.
In measurement modes 4–6, a compare exception occurs when the appropriate transition
occurs on the TIO signal. The Compare exception sets the TCF bit. TCF is cleared when a
value of one is written to it or when the timer compare interrupt is serviced.
To configure a timer exception, perform the following steps. The example at the right of each
step shows the register settings for configuring a Timer 0 compare interrupt. The order of the
steps is optional except that the timer should not be enabled (step 2e) until all other exception
configuration is complete:
1.
Configure the interrupt service routine (ISR):
a.
Load vector base address register
VBA (b23–8)
b.
2.
Define I_VEC to be equal to the VBA value (if that is nonzero). If it is defined,
I_VEC must be defined for the assembler before the interrupt equate file is
included.
c. Load the exception vector table entry: two-word fast interrupt, or jump/branch to
subroutine (long interrupt).
p:TIM0C
Configure the interrupt trigger:
a.
Enable and prioritize overall peripheral interrupt functionality.
IPRP (TOL[1–0])
b.
Enable a specific peripheral interrupt.
TCSR0 (TCIE)
c.
Unmask interrupts at the global level.
SR (I[1–0])
d.
Configure a peripheral interrupt-generating function.
TCSR0 (TC[7–4])
e.
Enable peripheral and associated signals.
TCSR0 (TE)
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10-4
Freescale Semiconductor
Operating Modes
10.3 Operating Modes
Each timer has operating modes that meet a variety of system requirements, as follows:
„
„
„
„
Timer
— GPIO, mode 0: Internal timer interrupt generated by the internal clock
— Pulse, mode 1: External timer pulse generated by the internal clock
— Toggle, mode 2: Output timing signal toggled by the internal clock
— Event counter, mode 3: Internal timer interrupt generated by an external clock
Measurement
— Input width, mode 4: Input pulse width measurement
— Input period, mode 5: Input signal period measurement
— Capture, mode 6: Capture external signal
PWM, mode 7: Pulse width modulation
Watchdog
— Pulse, mode 9: Output pulse, internal clock
— Toggle, mode 10: Output toggle, internal clock
To ensure proper operation, the TCSR TC[3–0] bits should be changed only when the timer is
disabled (that is, when TCSR[TE] is cleared).
10.3.1 Triple Timer Modes
For all triple timer modes, the following points are true:
„
„
„
„
„
The TCSR[TE] bit is set to clear the counter and enable the timer. Clearing TCSR[TE]
disables the timer.
The value to which the timer is to count is loaded into the TCPR. (This is true for all
modes except the measurement modes (modes 4 through 6).
The counter is loaded with the TLR value on the first clock.
If the counter overflows, TCSR[TOF] is set, and if TCSR[TOIE] is set, an overflow
interrupt is generated.
You can read the counter contents at any time from the Timer Count Register (TCR).
10.3.1.1 Timer GPIO (Mode 0)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
0
0
0
0
GPIO
Timer
GPIO
Internal
In Mode 0, the timer generates an internal interrupt when a counter value is reached, if the timer
compare interrupt is enabled (see Figure 10-3 and Figure 10-4). When the counter equals the
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-5
Triple Timer Module
TCPR value, TCSR[TCF] is set and a compare interrupt is generated if the TCSR[TCIE] bit is
set. If the TCSR[TRM] bit is set, the counter is reloaded with the TLR value at the next timer
clock and the count is resumed. If TCSR[TRM] is cleared, the counter continues to increment on
each timer clock signal. This process repeats until the timer is disabled.
Mode 0 (internal clock, no timer output): TRM = 1
N = write preload
M = write compare
first event
last event
TE
Clock
(CLK/2 or prescale CLK)
TLR
N
0
Counter (TCR)
TCPR
N
N+1
M
N
N+1
M
TCF (Compare Interrupt if TCIE = 1)
Figure 10-3. Timer Mode (TRM = 1)
Mode 0 (internal clock, no timer output): TRM = 0
N = write preload
M = write compare
first event
last event
TE
Clock
(CLK/2 or prescale CLK)
TLR
N
0
Counter (TCR)
TCPR
N
N+1
M
M+1
0
1
M
TCF (Compare Interrupt if TCIE = 1)
TOF (Overflow Interrupt if TCIE = 1)
Figure 10-4. Timer Mode (TRM = 0)
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10-6
Freescale Semiconductor
Operating Modes
10.3.1.2 Timer Pulse (Mode 1)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
0
0
1
1
Timer Pulse
Timer
Output
Internal
In Mode 1, the timer generates an external pulse on its TIO signal when the timer count reaches a
pre-set value. The TIO signal is loaded with the value of the TCSR[INV] bit. When the counter
matches the TCPR value, TCSR[TCF] is set and a compare interrupt is generated if the
TCSR[TCIE] bit is set. The polarity of the TIO signal is inverted for one timer clock period. If
TCSR[TRM] is set, the counter is loaded with the TLR value on the next timer clock and the
count is resumed. If TCSR[TRM] is cleared, the counter continues to increment on each timer
clock. This process repeats until TCSR[TE] is cleared (disabling the timer).
The TLR value in the TCPR sets the delay between starting the timer and generating the output
pulse. To generate successive output pulses with a delay of X clock cycles between signals, set
the TLR value to X/2 and set the TCSR[TRM] bit. This process repeats until the timer is
disabled.
Mode 1 (internal clock): TRM = 1
first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
TLR
N
0
Counter (TCR)
TCPR
N
N+1
M
N
N+1
M
TCF (Compare Interrupt if TCIE = 1)
TIO pin (INV = 0)
pulse width =
timer clock
period
TIO pin (INV = 1)
Figure 10-5. Pulse Mode (TRM = 1)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-7
Triple Timer Module
Mode 1 (internal clock): TRM = 0
first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
N
TLR
0
Counter (TCR)
N
N+1
M
M+1
0
1
M
TCPR
TCF (Compare Interrupt if TCIE = 1)
TIO pin (INV = 0)
pulse width =
timer clock
period
TIO pin (INV = 1)
TOF (Overflow Interrupt if TCIE = 1)
Figure 10-6. Pulse Mode (TRM = 0)
10.3.1.3
Timer Toggle (Mode 2)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
0
1
0
2
Toggle
Timer
Output
Internal
In Mode 2, the timer periodically toggles the polarity of the TIO signal. When the timer is
enabled, the TIO signal is loaded with the value of the TCSR[INV] bit. When the counter value
matches the value in the TCPR, the polarity of the TIO output signal is inverted. TCSR[TCF] is
set, and a compare interrupt is generated if the TCSR[TCIE] bit is set. If the TCSR[TRM] bit is
set, the counter is loaded with the value of the TLR when the next timer clock is received, and the
count resumes. If the TRM bit is cleared, the counter continues to increment on each timer clock.
This process repeats until the timer is cleared (disabling the timer). The TCPR[TLR] value sets
the delay between starting the timer and toggling the TIO signal. To generate output signals with
a delay of X clock cycles between toggles, set the TLR value to X/2, and set the TCSR[TRM] bit.
This process repeats until the timer is disabled (that is, TCSR[TE] is cleared).
DSP56321 Reference Manual, Rev. 1
10-8
Freescale Semiconductor
Operating Modes
Mode 2 (internal clock): TRM = 1
first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
TLR
N
0
Counter (TCR)
TCPR
N
N+1
M
N
N+1
M
TCF (Compare Interrupt if TCIE = 1)
TIO pin (INV = 0)
pulse width =
M - N clock
periods
TIO pin (INV = 1)
Figure 10-7. Toggle Mode, TRM = 1
Mode 2 (internal clock): TRM = 0
first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
TLR
N
0
Counter (TCR)
TCPR
N
N+1
M+1
M
0
1
M
TCF (Compare Interrupt if TCIE = 1)
TIO pin (INV = 0)
First toggle = M - N clock periods
Second and later toggles = 2 24 clock periods
TIO pin (INV = 1)
TOF (Overflow Interrupt if TCIE = 1)
Figure 10-8. Toggle Mode, TRM = 0
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-9
Triple Timer Module
10.3.1.4 Timer Event Counter (Mode 3)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
0
1
1
3
Event Counter
Timer
Input
External
In Mode 3, the timer counts external events and issues an interrupt (if interrupt enable bits are set)
when the timer counts a preset number of events. The timer clock signal can be taken from either
the TIO input signal or the prescaler clock output. If an external clock is used, it is synchronized
internally to the internal clock, and its frequency must be less than the DSP56321 internal
operating frequency divided by 4. The value of the TCSR[INV] bit determines whether
low-to-high (0 to 1) transitions or high-to-low (1 to 0) transitions increment the counter. If the
INV bit is set, high-to-low transitions increment the counter. If the INV bit is cleared,
low-to-high transitions increment the counter.
When the counter matches the value contained in the TCPR, TCSR[TCF] is set and a compare
interrupt is generated if the TCSR[TCIE] bit is set. If the TCSR[TRM] bit is set, the counter is
loaded with the value of the TLR when the next timer clock is received, and the count is resumed.
If the TCSR[TRM] bit is cleared, the counter continues to increment on each timer clock. This
process repeats until the timer is disabled
Mode 3 (internal clock): TRM = 1
first event
N = write preload
M = write compare
TE
if clock source
is from TIO pin,
TIO < CPUCLK + 4
Clock
(TIO pin or prescale CLK)
TLR
N
0
Counter (TCR)
TCPR
N
N+1
M
N
N+1
M
TCF (Compare Interrupt if TCIE = 1)
interrupts every
M - N clock
periods
NOTE: If INV = 1, counter is clocked on 1-to-0 clock transitions, instead of 0-to-1 transitions.
Figure 10-9. Event Counter Mode, TRM = 1
DSP56321 Reference Manual, Rev. 1
10-10
Freescale Semiconductor
Operating Modes
Mode 3 (internal clock): TRM = 0
N = write preload
M = write compare
if clock source is from TIO pin,
TIO < CPUCLK + 4
first event
TE
Clock
(TIO pin or prescale CLK)
N
TLR
0
Counter (TCR)
N
N+1
M+1
M
0
1
M
TCPR
TCF (Compare Interrupt if TCIE = 1)
TOF (Overflow Interrupt if TCIE = 1)
NOTE: If INV = 1, counter is clocked on 1-to-0 clock transitions, instead of 0-to-1 transitions.
Figure 10-10. Event Counter Mode, TRM = 0
10.3.2 Signal Measurement Modes
The following signal measurement and pulse width modulation modes are provided:
„
„
„
„
Measurement input width (Mode 4)
Measurement input period (Mode 5)
Measurement capture (Mode 6)
Pulse width modulation (PWM) mode (Mode 7)
The external signal synchronizes with the internal clock that increments the counter. This
synchronization process can cause the number of clocks measured for the selected signal value to
vary from the actual signal value by plus or minus one counter clock cycle.
10.3.2.1 Measurement Input Width (Mode 4)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
1
0
0
4
Input width
Measurement
Input
Internal
In Mode 4, the timer counts the number of clocks that occur between opposite edges of an input
signal. After the first appropriate transition (as determined by the TCSR[INV] bit) occurs on the
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Freescale Semiconductor
10-11
Triple Timer Module
input signal, the counter is loaded with the TLR value. If TCSR[INV] is set, the timer starts
on the first high-to-low (1 to 0) signal transition on the TIO signal. If the INV bit is cleared, the
timer starts on the first low-to-high (that is, 0 to 1) transition on the TIO signal. When the first
transition opposite in polarity to the INV bit setting occurs on the TIO signal, the counter stops.
TCSR[TCF] is set and a compare interrupt is generated if the TCSR[TCIE] bit is set. The value of
the counter (which measures the width of the TIO pulse) is loaded into the TCR, which can be
read to determine the external signal pulse width. If the TCSR[TRM] bit is set, the counter is
loaded with the TLR value on the first timer clock received following the next valid transition on
the TIO input signal, and the count resumes. If TCSR[TRM] is cleared, the counter continues to
increment on each timer clock. This process repeats until the timer is disabled.
TIO
Mode 4 (internal clock): TRM = 1
first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
TLR
Counter
N
0
N
N+1
M
N+1
Next 0-to-1 edge
on TIO loads
counter and
process repeats
M
TCR
width being measured
TIO pin
Interrupt Service
reads TCR; width
= M - N clock
periods
TCF (Compare Interrupt if TCIE = 1)
NOTE: If INV = 1, a 1-to-0 edge on TIO loads the counter, and a 0-to-1 edge on TIO
stops the counter and loads TCR with the count.
Figure 10-11. Pulse Width Measurement Mode, TRM = 1
DSP56321 Reference Manual, Rev. 1
10-12
Freescale Semiconductor
Operating Modes
Mode 4 (internal clock): TRM = 1 first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
N
TLR
0
Counter
N
N+1
M
M
TCR
width being measured
TIO pin
TCF (Compare Interrupt if TCIE = 1)
NOTE: If INV = 1, a 1-to-0 edge on TIO loads the counter, and a 0-to-1 edge on TIO
stops the counter and loads TCR with the count.
Next 0-to-1
N + 1edge
on TIO starts
counter from current
count and process
repeats. Overflow
may occur (TOF = 1).
Interrupt Service
reads TCR for
accumulated width
of M - N clock periods.
Figure 10-12. Pulse Width Measurement Mode, TRM = 0
10.3.2.2 Measurement Input Period (Mode 5)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
1
0
1
5
Input period
Measurement
Input
Internal
In Mode 5, the timer counts the period between the reception of signal edges of the same polarity
across the TIO signal. The value of the INV bit determines whether the period is measured
between consecutive low-to-high (0 to 1) transitions of TIO or between consecutive high-to-low
(1 to 0) transitions of TIO. If INV is set, high-to-low signal transitions are selected. If INV is
cleared, low-to-high signal transitions are selected. After the first appropriate transition occurs on
the TIO input signal, the counter is loaded with the TLR value. On the next signal transition of the
same polarity that occurs on TIO, TCSR[TCF] is set, and a compare interrupt is generated if the
TCSR[TCIE] bit is set. The contents of the counter load into the TCR. The TCR then contains the
value of the time that elapsed between the two signal transitions on the TIO signal. After the
second signal transition, if the TCSR[TRM] bit is set, the TCSR[TE] bit is set to clear the counter
and enable the timer. The counter is repeatedly loaded and incremented until the timer is
disabled. If the TCSR[TRM] bit is cleared, the counter continues to increment until it overflows.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-13
Triple Timer Module
Mode 5 (internal clock): TRM = 1 first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
TLR
N
0
Counter
N
N+1
M
N
Counter continues
counting,
N +does
1
not stop
M
TCR
period being measured
TIO pin
Interrupt Service
reads TCR; period
= M - N clock
periods
TCF (Compare Interrupt if TCIE = 1)
NOTE: If INV = 1, a 1-to-0 edge on TIO loads the counter, and a 0-to-1 edge on TIO
loads TCR with count and the counter with N.
Figure 10-13. Period Measurement Mode, TRM = 1
Mode 5 (internal clock): TRM = 0 first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
TLR
Counter
N
0
N
N+1
M
M
TCR
TIO pin
M+1
Counter continues
counting,
N +does
1
not stop. Overflow
may occur (TOF=1).
period being measured
TCF (Compare Interrupt if TCIE = 1)
Interrupt Service
reads TCR; period
= M - N clock
periods
NOTE: If INV = 1, a 1-to-0 edge on TIO loads the counter, and a 0-to-1 edge on TIO
loads TCR with count and the counter with N.
Figure 10-14. Period Measurement Mode, TRM = 0
DSP56321 Reference Manual, Rev. 1
10-14
Freescale Semiconductor
Operating Modes
10.3.2.3 Measurement Capture (Mode 6)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
1
1
0
6
Capture
Measurement
Input
Internal
In Mode 6, the timer counts the number of clocks that elapse between when the timer starts and
when an external signal is received. At the first appropriate transition of the external clock
detected on the TIO signal, TCSR[TCF] is set and, if the TCSR[TCIE] bit is set, a compare
interrupt is generated. The counter halts. The contents of the counter are loaded into the TCR.
The value of the TCR represents the delay between the setting of the TCSR[TE] bit and the
detection of the first clock edge signal on the TIO signal. The value of the INV bit determines
whether a high-to-low (1 to 0) or low-to-high (0 to 1) transition of the external clock signals the
end of the timing period. If the INV bit is set, a high-to-low transition signals the end of the
timing period. If INV is cleared, a low-to-high transition signals the end of the timing period.
Mode 6 (internal clock): TRM = 1
first event
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
TLR
Counter
N
0
N
N+1
M
Counter stops
counting;
N +overflow
1
may occur before
capture (TOF = 1)
M
TCR
TIO pin
N
delay being measured
TCF (Compare Interrupt if TCIE = 1)
Interrupt Service
reads TCR; delay
= M - N clock
periods
NOTE: If INV = 1, a 1-to-0 edge on TIO loads TCR with count and stops the counter.
Figure 10-15. Capture Measurement Mode, TRM = 0
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-15
Triple Timer Module
10.3.3 Pulse Width Modulation (PWM, Mode 7)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
0
1
1
1
7
Pulse width modulation
PWM
Output
Internal
In Mode 7, the timer generates periodic pulses of a preset width. When the counter equals the
value in the TCPR, the TIO output signal is toggled and TCSR[TCF] is set. The contents of the
counter are placed into the TCR. If the TCSR[TCIE] bit is set, a compare interrupt is generated.
The counter continues to increment on each timer clock.
If counter overflow occurs, the TIO output signal is toggled, TCSR[TOF] is set, and an overflow
interrupt is generated if the TCSR[TOIE] bit is set. If the TCSR[TRM] bit is set, the counter is
loaded with the TLR value on the next timer clock and the count resumes. If the TCSR[TRM] bit
is cleared, the counter continues to increment on each timer clock. This process repeats until the
timer is disabled.
When the TCSR[TE] bit is set and the counter starts, the TIO signal assumes the value of INV. On
each subsequent toggle of the TIO signal, the polarity of the TIO signal is reversed. For example, if
the INV bit is set, the TIO signal generates the following signal: 1010. If the INV bit is cleared, the
TIO signal generates the following signal: 0101.
The value of the TLR determines the output period ($FFFFFF − TLR + 1). The timer counter
increments the initial TLR value and toggles the TIO signal when the counter value exceeds
$FFFFFF. The duty cycle of the TIO signal is determined by the value in the TCPR. When the
value in the TLR increments to a value equal to the value in the TCPR, the TIO signal is toggled.
The duty cycle is equal to ($FFFFFF – TCPR) divided by ($FFFFFF − TLR + 1). For a 50
percent duty cycle, the value of TCPR is equal to ($FFFFFF + TLR + 1)/2.
Note:
The value in TCPR must be greater than the value in TLR.
DSP56321 Reference Manual, Rev. 1
10-16
Freescale Semiconductor
Operating Modes
Period = $FFFFFF - TLR + 1
Duty cycle = ($FFFFFF - TCPR)
Ensure that TCPR > TLR for correct functionality
Mode 7 (internal clock): TRM = 1
N = write preload
M = write compare
first event
TE
Clock
(CLK/2 or prescale CLK)
N
TLR
0
Counter (TCR)
N
M
M+1
0
N
N+1
M
TCPR
TCF (Compare Interrupt if TCIE = 1)
TCF (Overflow Interrupt if TDIE = 1)
TIO pin (INV = 0)
TIO pin (INV = 1)
Pulse width
Period
Figure 10-16. Pulse Width Modulation Toggle Mode, TRM = 1
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-17
Triple Timer Module
Period = $FFFFFF - TLR + 1
Duty cycle = ($FFFFFF - TCPR)
Ensure that TCPR > TLR for correct functionality
Mode 7 (internal clock): TRM = 0
N = write preload
M = write compare
first event
TE
Clock
(CLK/2 or prescale CLK)
N
TLR
0
Counter (TCR)
N
M
M+1
0
1
2
M
TCPR
TCF (Compare Interrupt if TCIE = 1)
TCF (Overflow Interrupt if TDIE = 1)
TIO pin (INV = 0)
TIO pin (INV = 1)
Pulse width
Period
NOTE: On overflow, TCR is loaded with the value of TLR.
Figure 10-17. Pulse Width Modulation Toggle Mode, TRM = 0
10.3.4 Watchdog Modes
The following watchdog timer modes are provided:
„
„
Watchdog Pulse
Watchdog Toggle
DSP56321 Reference Manual, Rev. 1
10-18
Freescale Semiconductor
Operating Modes
10.3.4.1 Watchdog Pulse (Mode 9)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
1
0
0
1
9
Pulse
Watchdog
Output
Internal
In Mode 9, the timer generates an external signal at a preset rate. The signal period is equal to the
period of one timer clock. After the counter reaches the value in the TCPR, if the TCSR[TRM]
bit is set, the counter is loaded with the TLR value on the next timer clock and the count resumes.
Therefore TRM = 1 is not useful for watchdog functions. If the TCSR[TRM] bit is cleared, the
counter continues to increment on each subsequent timer clock. This process repeats until the
timer is disabled (that is, TCSR[TE] is cleared). If the counter overflows, a pulse is output on the
TIO signal with a pulse width equal to the timer clock period. If the INV bit is set, the pulse
polarity is high (logical 1). If INV is cleared, the pulse polarity is low (logical 0). The counter
reloads when the TLR is written with a new value while the TCSR[TE] bit is set. In Mode 9,
internal logic preserves the TIO value and direction for an additional 2.5 internal clock cycles after
the hardware RESET signal is asserted. This convention ensures that a valid RESET signal is
generated when the TIO signal resets the DSP56321.
Mode 9 (internal clock): TRM = 0
N = write preload
M = write compare
(Software does not reset watchdog timer; watchdog times out)
first event
TRM = 1 is not useful for watchdog function
TE
Clock
(CLK/2 or prescale CLK)
N
TLR
0
Counter (TCR)
N
N+1
M
M+1
0
1
M
TCPR
TCF (Compare Interrupt if TCIE = 1)
TOF (Overflow Interrupt if TOIE = 1)
float
TIO pin (INV = 0)
float
TIO pin (INV = 1)
pulse width
= timer
clock period
low
high
TIO can connect to the RESET pin, internal hardware preserves the TIO value and
direction for an additional 2.5 clocks to ensure a reset of valid length.
Figure 10-18. Watchdog Pulse Mode
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-19
Triple Timer Module
10.3.4.2 Watchdog Toggle (Mode 10)
Bit Settings
Mode Characteristics
TC3
TC2
TC1
TC0
Mode
Name
Function
TIO
Clock
1
0
1
0
10
Toggle
Watchdog
Output
Internal
In Mode 10, the timer toggles an external signal after a preset period. The TIO signal is set to the
value of the INV bit.When the counter equals the value in the TCPR, TCSR[TCF] is set, and a
compare interrupt is generated if the TCSR[TCIE] bit is also set. If the TCSR[TRM] bit is set, the
counter loads with the TLR value on the next timer clock and the count resumes. Therefore, TRM
= 1 is not useful for watchdog functions. If the TCSR[TRM] bit is cleared, the counter continues
to increment on each subsequent timer clock. When a counter overflow occurs, the polarity of the
TIO output signal is inverted. The counter is reloaded whenever the TLR is written with a new
value while the TCSR[TE] bit is set. This process repeats until the timer is disabled. In Mode 10,
internal logic preserves the TIO value and direction for an additional 2.5 internal clock cycles after
the hardware RESET signal is asserted. This convention ensures that a valid reset signal is
generated when the TIO signal resets the DSP56321.
Mode 10 (internal clock): TRM = 0
first event
TRM = 1 is not useful for watchdog function
N = write preload
M = write compare
TE
Clock
(CLK/2 or prescale CLK)
N
TLR
0
Counter (TCR)
N
N+1
M
M+1
0
1
M
TCPR
TCF (Compare Interrupt if TCIE = 1)
TOF (Overflow Interrupt if TOIE = 1)
float
low
TIO pin (INV = 0)
float
high
TIO pin (INV = 1)
TIO can connect to the RESET pin, internal hardware preserves the TIO value and
direction for an additional 2.5 clocks to ensure a reset of valid length.
Figure 10-19. Watchdog Toggle Mode
10.3.4.3 Reserved Modes
Modes 8, 11, 12, 13, 14, and 15 are reserved.
DSP56321 Reference Manual, Rev. 1
10-20
Freescale Semiconductor
Triple Timer Module Programming Model
10.3.5 Special Cases
The following special cases apply during wait and stop state.
„
„
Timer behavior during wait — Timer clocks are active during the execution of the WAIT
instruction and timer activity is undisturbed. If a timer interrupt is generated, the
DSP56321 leaves the wait state and services the interrupt.
Timer behavior during stop — During execution of the STOP instruction, the timer clocks
are disabled, timer activity stops, and the TIO signals are disconnected. Any external
changes that happen to the TIO signals are ignored when the DSP56321 is in stop state. To
ensure correct operation, disable the timers before the DSP56321 is placed in stop state.
10.3.6 DMA Trigger
Each timer can also trigger DMA transfers if a DMA channel is programmed to be triggered by a
timer event. The timer issues a DMA trigger on every event in all modes of operation. To ensure
that all DMA triggers are serviced, provide for the preceding DMA trigger to be serviced before
the DMA channel receives the next trigger.
10.4 Triple Timer Module Programming Model
The timer programmer’s model in Figure 10-20 shows the structure of the timer registers.
10.4.1 Prescaler Counter
The prescaler counter is a 21-bit counter that decrements on the rising edge of the prescaler input
clock. The counter is enabled when at least one of the three timers is enabled (that is, one or more
of the timer enable bits are set) and is using the prescaler output as its source (that is, one or more
of the PCE bits are set).
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-21
Triple Timer Module
23
0
Timer Prescaler Load
Register (TPLR)
TPLR = $FFFF83
23
0
Timer Prescaler Count
Register (TPCR)
TPLR = $FFFF82
23
22
21
20
19
18
17
16
Timer Control/Status
Register (TCSR)
TCF TOF
14
15
PCE
13
12
11
DO
DI
DIR
10
9
8
TCSR0 = $FFFF8F
TRM
INV
TCSR1 = $FFFF8B
TCSR2 = $FFFF87
7
6
TC3
TC2 TC1
23
5
4
3
TC0
2
1
TCIE TOIE
0
TE
0
Timer Load
Register (TLR)
TLR0 = $FFFF8E
TLR1 = $FFFF8A
TLR2 = $FFFF86
23
0
Timer Compare
Register (TCPR)
TCPR0 = $FFFF8D
TCPR1 = $FFFF89
TCPR2 = $FFFF85
23
0
Timer Count
Register (TCR)
TCR0 = $FFFF8C
TCR1 = $FFFF88
TCR2 = $FFFF84
Reserved bit. Read as 0. Write with 0 for future compatibility
Figure 10-20. Timer Module Programmer’s Model
DSP56321 Reference Manual, Rev. 1
10-22
Freescale Semiconductor
Triple Timer Module Programming Model
10.4.2 Timer Prescaler Load Register (TPLR)
The TPLR is a read/write register that controls the prescaler divide factor (that is, the number that
the prescaler counter loads and begins counting from) and the source for the prescaler input
clock.
23
22
21
20
19
18
17
16
15
14
13
12
PS1
PS0
PL20
PL19
PL18
PL17
PL16
PL15
PL14
PL13
PL12
11
10
9
8
7
6
5
4
3
2
1
0
PL11
PL10
PL9
PL8
PL7
PL6
PL5
PL4
PL3
PL2
PL1
PL0
— Reserved bit. Read as 0. Write to 0 for future compatibility
Table 10-1. Timer Prescaler Load Register (TPLR) Bit Definitions
Bit Number
Bit Name
23
22–21
PS[1–0]
Reset Value
Description
0
Reserved. Write to zero for future compatibility.
0
Prescaler Source
Control the source of the prescaler clock. The prescaler’s use of a TIO signal
is not affected by the TCSR settings of the timer of the corresponding TIO
signal. If the prescaler source clock is external, the prescaler counter is
incremented by signal transitions on the TIO signal. The external clock is
internally synchronized to the internal clock. The external clock frequency
must be lower than the DSP56321 internal operating frequency divided by 4
(that is, CLK/4).
NOTE: To ensure proper operation, change the PS[1–0] bits only when the
prescaler counter is disabled. Disable the prescaler counter by clearing
TCSR[TE] of each of three timers.
20–0
PL[20–0]
0
PS1
PS0
Prescaler Clock Source
0
0
Internal CLK/2
0
1
TIO0
1
0
TIO1
1
1
TIO2
Prescaler Preload Value
Contains the prescaler preload value, which is loaded into the prescaler
counter when the counter value reaches 0 or the counter switches state from
disabled to enabled. If PL[20–0] = N, then the prescaler counts N+1 source
clock cycles before generating a prescaler clock pulse. Therefore, the
prescaler divide factor = (preload value) + 1.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-23
Triple Timer Module
10.4.3 Timer Prescaler Count Register (TPCR)
The TPCR is a read-only register that reflects the current value in the prescaler counter.
23
22
21
20
19
18
17
16
15
14
13
12
PC20
PC19
PC18
PC17
PC16
PC15
PC14
PC13
PC12
11
10
9
8
7
6
5
4
3
2
1
0
PC11
PC10
PC9
PC8
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
13
12
DO
DI
2
1
0
TCIE
TOIE
TE
Reserved bit; read as 0; write to 0 for future compatibility
Table 10-2. Timer Prescaler Count Register (TPCR) Bit Definitions
Bit Number
Bit Name
Reset Value
23–21
20–0
PC[20–0]
Description
0
Reserved. Write to zero for future compatibility.
0
Prescaler Counter Value
Contain the current value of the prescaler counter.
10.4.4 Timer Control/Status Register (TCSR)
The TCSR is a read/write register controlling the timer and reflecting its status.
23
11
DIR
22
10
21
20
19
18
17
16
15
TCF
TOF
9
8
7
6
5
4
TRM
INV
TC3
TC2
TC1
TC0
14
PCE
3
Reserved. Read as 0. Write to 0 for future compatibility
Table 10-3. Timer Control/Status Register (TCSR) Bit Definitions
Bit Number
23–22
Bit Name
Reset Value
0
Description
Reserved. Write to zero for future compatibility.
DSP56321 Reference Manual, Rev. 1
10-24
Freescale Semiconductor
Triple Timer Module Programming Model
Table 10-3. Timer Control/Status Register (TCSR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
21
TCF
0
Timer Compare Flag
Indicate that the event count is complete. In timer, PWM, and watchdog modes,
the TCF bit is set after (M – N + 1) events are counted. (M is the value in the
compare register and N is the TLR value.) In measurement modes, the TCF bit
is set when the measurement completes. Writing a one to the TCF bit clears it.
A zero written to the TCF bit has no effect. The bit is also cleared when the
timer compare interrupt is serviced. The TCF bit is cleared by a hardware
RESET signal, a software RESET instruction, the STOP instruction, or by
clearing the TCSR[TE] bit to disable the timer.
NOTE: The TOF and TCF bits are cleared by a 1 written to the specific bit. To
ensure that only the target bit is cleared, do not use the BSET command. The
proper way to clear these bits is to write 1, using a MOVEP instruction, to the
flag to be cleared and 0 to the other flag.
20
TOF
0
Timer Overflow Flag
Indicates that a counter overflow has occurred. This bit is cleared by writing a
one to the TOF bit. Writing a zero to TOF has no effect. The bit is also cleared
when the timer overflow interrupt is serviced. The TOF bit is cleared by a
hardware RESET signal, a software RESET instruction, the STOP instruction,
or by clearing the TCSR[TE] bit to disable the timer.
19–16
15
PCE
14
0
Reserved. Write to zero for future compatibility.
0
Prescaler Clock Enable
Selects the prescaler clock as the timer source clock. When PCE is cleared, the
timer uses either an internal (CLK/2) signal or an external (TIO) signal as its
source clock. When PCE is set, the prescaler output is the timer source clock
for the counter, regardless of the timer operating mode. To ensure proper
operation, the PCE bit is changed only when the timer is disabled. The PS[1–0]
bits of the TPLR determine which source clock is used for the prescaler. A timer
can be clocked by a prescaler clock that is derived from the TIO of another
timer.
0
Reserved. Write to zero for future compatibility.
13
DO
0
Data Output
The source of the TIO value when it is a data output signal. The TIO signal is a
data output when the GPIO mode is enabled and DIR is set. A value written to
the DO bit is written to the TIO signal. If the INV bit is set, the value of the DO
bit is inverted when written to the TIO signal. When the INV bit is cleared, the
value of the DO bit is written directly to the TIO signal. When GPIO mode is
disabled, writing to the DO bit has no effect.
12
DI
0
Data Input
Reflects the value of the TIO signal. If the INV bit is set, the value of the TIO
signal is inverted before it is written to the DI bit. If the INV bit is cleared, the
value of the TIO signal is written directly to the DI bit.
11
DIR
0
Direction
Determines the behavior of the TIO signal when it functions as a GPIO signal.
When DIR is set, the TIO signal is an output; when DIR is cleared, the TIO
signal is an input. The TIO signal functions as a GPIO signal only when the
TC[3–0] bits are cleared. If any of the TC[3–0] bits are set, then the GPIO
function is disabled, and the DIR bit has no effect.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-25
Triple Timer Module
Table 10-3. Timer Control/Status Register (TCSR) Bit Definitions (Continued)
Bit Number
Bit Name
10
Reset Value
Description
0
Reserved. Write to zero for future compatibility.
9
TRM
0
Timer Reload Mode
Controls the counter preload operation. In timer (0–3) and watchdog (9–10)
modes, the counter is preloaded with the TLR value after the TCSR[TE] bit is
set and the first internal or external clock signal is received. If the TRM bit is
set, the counter is reloaded each time after it reaches the value contained by
the TCR. In PWM mode (7), the counter is reloaded each time counter overflow
occurs. In measurement (4–5) modes, if the TRM and the TCSR[TE] bits are
set, the counter is preloaded with the TLR value on each appropriate edge of
the input signal. If the TRM bit is cleared, the counter operates as a free
running counter and is incremented on each incoming event.
8
INV
0
Inverter
Affects the polarity definition of the incoming signal on the TIO signal when TIO
is programmed as input. It also affects the polarity of the output pulse
generated on the TIO signal when TIO is programmed as output. See Table
10-4, Inverter (INV) Bit Operation, on page 10-28. The INV bit does not affect
the polarity of the prescaler source when the TIO is input to the prescaler.
NOTE: The INV bit affects both the timer and GPIO modes of operation. To
ensure correct operation, change this bit only when one or both of the following
conditions is true: the timer is disabled (the TCSR[TE] bit is cleared). The timer
is in GPIO mode.
DSP56321 Reference Manual, Rev. 1
10-26
Freescale Semiconductor
Triple Timer Module Programming Model
Table 10-3. Timer Control/Status Register (TCSR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
7–4
TC[3–0]
0
Timer Control
Control the source of the timer clock, the behavior of the TIO signal, and the
Timer mode of operation. Section 10.3, Operating Modes, on page 10-5
describes the timer operating modes in detail. To ensure proper operation, the
TC[3–0] bits should be changed only when the timer is disabled (that is, when
the TCSR[TE] bit is cleared). If the clock is external, the counter is incremented
by the transitions on the TIO signal. The external clock is internally
synchronized to the internal clock, and its frequency should be lower than the
internal operating frequency divided by 4 (that is, CLK/4).
Bit Settings
TC3
TC2
TC1
TC0
Mode
Number
Mode
Function
TIO
Clock
0
0
0
0
0
Timer and
GPIO
GPIO 1
Internal
0
0
0
1
1
Timer pulse
Output
Internal
0
0
1
0
2
Timer toggle
Output
Internal
0
0
1
1
3
Event counter
Input
External
0
1
0
0
4
Input width
measurement
Input
Internal
0
1
0
1
5
Input period
measurement
Input
Internal
0
1
1
0
6
Capture event
Input
Internal
0
1
1
1
7
Pulse width
modulation
1
0
0
0
8
Reserved
—
1
0
0
1
9
Watchdog
pulse
Output Internal
1
0
1
0
10
Watchdog
Toggle
Output Internal
1
0
1
1
11
Reserved
—
—
1
1
0
0
12
Reserved
—
—
1
1
0
1
13
Reserved
—
—
1
1
1
0
14
Reserved
—
—
1
1
1
1
15
Reserved
—
—
Notes: 1.
3
0
Mode Characteristics
Output Internal
—
The GPIO function is enabled only if all of the TC[3–0] bits are 0.
Reserved. Write to zero for future compatibility.
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Freescale Semiconductor
10-27
Triple Timer Module
Table 10-3. Timer Control/Status Register (TCSR) Bit Definitions (Continued)
Bit Number
Bit Name
Reset Value
Description
2
TCIE
0
Timer Compare Interrupt Enable
Enables/disables the timer compare interrupts. When set, TCIE enables the
compare interrupts. In the timer, pulse width modulation (PWM), or watchdog
modes, a compare interrupt is generated after the counter value matches the
value of the TCPR. The counter starts counting up from the number loaded
from the TLR and if the TCPR value is M, an interrupt occurs after (M – N + 1)
events, where N is the value of TLR. When cleared, the TCSR[TCIE] bit
disables the compare interrupts.
1
TOIE
0
Timer Overflow Interrupt Enable
Enables timer overflow interrupts. When set, TOIE enables overflow interrupt
generation. The timer counter can hold a maximum value of $FFFFFF. When
the counter value is at the maximum value and a new event causes the counter
to be incremented to $000000, the timer generates an overflow interrupt. When
cleared, the TOIE bit disables overflow interrupt generation.
0
TE
0
Timer Enable
Enables/disables the timer. When set, TE enables the timer and clears the
timer counter. The counter starts counting according to the mode selected by
the timer control (TC[3–0]) bit values. When clear, TE bit disables the timer.
NOTE: When all three timers are disabled and the signals are not in GPIO
mode, all three TIO signals are tri-stated. To prevent undesired spikes on the
TIO signals when you switch from tri-state into active state, these signals
should be tied to the high or low signal state by pull-up or pull-down resistors.
Table 10-4. Inverter (INV) Bit Operation
TIO Programmed as Input
TIO Programmed as Output
Mode
INV = 0
INV = 1
0
GPIO signal on the TIO
signal read directly.
GPIO signal on the TIO
signal inverted.
1
Counter is incremented on
the rising edge of the signal
from the TIO signal.
Counter is incremented on
the falling edge of the
signal from the TIO signal.
2
Counter is incremented on
the rising edge of the signal
from the TIO signal.
Counter is incremented on
the falling edge of the
signal from the TIO signal.
3
Counter is incremented on
the rising edge of the signal
from the TIO signal.
Counter is incremented on
the falling edge of the
signal from the TIO signal.
Width of the high input
pulse is measured.
Width of the low input
pulse is measured.
4
INV = 0
Bit written to GPIO
put on TIO signal
directly.
—
Initial output put on
TIO signal directly.
INV = 1
Bit written to GPIO
inverted and put on
TIO signal.
—
Initial output inverted
and put on TIO signal.
—
—
—
—
DSP56321 Reference Manual, Rev. 1
10-28
Freescale Semiconductor
Triple Timer Module Programming Model
Table 10-4. Inverter (INV) Bit Operation (Continued)
TIO Programmed as Input
TIO Programmed as Output
Mode
5
6
INV = 0
INV = 1
Period is measured between
the rising edges of the input
signal.
Period is measured
between the falling edges
of the input signal.
Event is captured on the
rising edge of the signal
from the TIO signal.
Event is captured on the
falling edge of the signal
from the TIO signal.
7
—
—
—
—
—
Pulse generated by
the timer has
positive polarity.
Pulse generated by the
timer has negative
polarity.
—
Pulse generated by
the timer has
positive polarity.
Pulse generated by the
timer has negative
polarity.
—
Pulse generated by
the timer has
positive polarity.
Pulse generated by the
timer has negative
polarity.
10
—
INV = 1
—
9
—
INV = 0
10.4.5 Timer Load Register (TLR)
The TLR is a 24-bit write-only register. In all modes, the counter is preloaded with the TLR value
after the TCSR[TE] bit is set and a first event occurs.
„
„
„
„
„
In timer modes, if the TCSR[TRM] bit is set, the counter is reloaded each time after it
reaches the value contained by the timer compare register and the new event occurs.
In measurement modes, if TCSR[TRM] and TCSR[TE] are set, the counter is reloaded
with the value in the TLR on each appropriate edge of the input signal.
In PWM modes, if TCSR[TRM] is set, the counter is reloaded each time after it overflows
and the new event occurs.
In watchdog modes, if TCSR[TRM] is set, the counter is reloaded each time after it
reaches the value contained by the timer compare register and the new event occurs. In
this mode, the counter is also reloaded whenever the TLR is written with a new value
while TCSR[TE] is set.
In all modes, if TCSR[TRM] is cleared (TRM = 0), the counter operates as a free-running
counter.
10.4.6 Timer Compare Register (TCPR)
The TCPR is a 24-bit read/write register that contains the value to be compared to the counter
value. These two values are compared every timer clock after TCSR[TE] is set. When the values
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
10-29
Triple Timer Module
match, the timer compare flag bit is set and an interrupt is generated if interrupts are enabled (that
is, the timer compare interrupt enable bit in the TCSR is set). The TCPR is ignored in
measurement modes.
10.4.7 Timer Count Register (TCR)
The TCR is a 24-bit read-only register. In timer and watchdog modes, the contents of the counter
can be read at any time from the TCR register. In measurement modes, the TCR is loaded with
the current value of the counter on the appropriate edge of the input signal, and its value can be
read to determine the width, period, or delay of the leading edge of the input signal. When the
timer is in measurement mode, the TIO signal is used for the input signal.
DSP56321 Reference Manual, Rev. 1
10-30
Freescale Semiconductor
Enhanced Filter Coprocessor
11
The enhanced filter coprocessor (EFCOP) peripheral module functions as a general-purpose,
fully programmable filter. It has optimized modes of operation to perform single-channel and
multichannel real and complex finite impulse response (FIR) filtering with and without adaptive
FIR filtering and decimation or single-channel and multichannel infinite impulse response (IIR)
filtering. EFCOP filter operations complete concurrently with DSP56300 core operations, with
minimal CPU intervention. For optimal performance, the EFCOP has one dedicated Filter
Multiplier Accumulator (FMAC) unit. Thus, for filtering, the combination Core/EFCOP offers
dual MAC capabilities. Its dedicated modes make the EFCOP a very flexible filter coprocessor
with operations optimized for cellular base station applications. The EFCOP architecture also
allows adaptive FIR filtering in which the filter coefficient update is performed using any
fixed-point standard or non-standard adaptive algorithms—for example, the well-known Least
Mean Square (LMS) algorithm, the Normalized LMS, and customized update algorithms. In a
transceiver base station, the EFCOP can perform complex matched filtering to maximize the
signal-to-noise ratio (SNR) within an equalizer. In a transcoder base station or a mobile switching
center, the EFCOP can perform all types of FIR and IIR filtering within a vocoder, as well as
LMS-type echo cancellation. This chapter describes the EFCOP features, architecture, operation,
and programming model.
11.1 Features
„
„
„
Fully programmable real/complex filter machine with 24-bit resolution
FIR filter options
— Four modes of operation with optimized performance:
• Mode 0, FIR machine with real taps
• Mode 1, FIR machine with complex taps
• Mode 2, Complex FIR machine generating pure real/imaginary outputs alternately
• Mode 3—Magnitude (calculate the square of each input sample)
— 4-bit decimation factor in FIR filters providing up to 1:16 decimation ratio
— Easy to use adaptive mode supporting true or delayed LMS-type algorithms
— K-constant input register for coefficient updates (in adaptive mode)
IIR filter options:
— Direct form 1 (DFI) and direct form 2 (DFII) configurations
— Three optional output scaling factors (1, 8, or 16)
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Freescale Semiconductor
11-1
Enhanced Filter Coprocessor
„
„
„
„
„
„
„
„
„
„
„
„
„
Multichannel mode to process multiple, equal-length filter channels (up to 64)
simultaneously with minimal core intervention
Optional input scaling for both FIR and IIR filters
Two filter initialization modes
— No initialization
— Data initialization
Sixteen-bit arithmetic mode support
Three rounding options available:
— No rounding
— Convergent rounding
— Two’s complement rounding
Arithmetic saturation mode support for bit-exact applications
Sticky saturation status bit indication
Sticky data/coefficient transfer contention status bit
4-word deep input data buffer for maximum performance
EFCOP-shared and core-shared 12 K-word filter data memory bank and 12 K-word filter
coefficient memory bank
Two memory bank base address pointers, one for data memory (shared with X memory)
and one for coefficient memory (shared with Y memory)
I/O data transfers via core or DMA with minimal core intervention
Core-concurrent operation with minimal core intervention
11.2 Architecture Overview
As Figure 11-1 shows, the EFCOP comprises these main functional blocks:
„
„
„
„
„
„
Peripheral module bus (PMB) interface, including:
— Data input buffer
— Constant input buffer
— Output buffer
— Filter counter
Filter data memory (FDM) bank
Filter coefficient memory (FCM) bank
Filter multiplier accumulator (FMAC) machine
Address generator
Control logic
DSP56321 Reference Manual, Rev. 1
11-2
Freescale Semiconductor
Architecture Overview
DMA BUS
PMB
Interface
GDB BUS
FDIR
Control
Logic
4-Word
Data Input Buffer
FDM
X Memory
Shared
RAM
DATA
Memory Bank
24-bit
FCNT
Filter Count
FCBA
Coeff. Base Ad.
FDBA
Data Base Ad.
Address
Generator
Y Memory
Shared
RAM
FCM
COEFFICIENT
Memory Bank
24-bit
FMAC
24x24 -> 56-bit
Rounding & Limiting
FKIR
Filter Constant
Output Buffer
FDOR
Figure 11-1. EFCOP Block Diagram
11.2.1 PMB Interface
The PMB interface block contains control and status registers, buffers the internal bus from the
PMB, decodes and generates addresses, and controls the handshake signals required for DMA
and interrupt operations. The block generates interrupt and DMA trigger signals for data
transfers. The interface registers accessible to the DSP56300 core through the PMB are
summarized in Table 11-1.
Table 11-1. EFCOP Registers Accessible Through the PMB
Register Name
Description
Filter Data Input Register
(FDIR)
A 4-word-deep 24-bit-wide FIFO used for DSP-to-EFCOP data transfers. Data from the FDIR is
transferred to the FDM for filter processing.
Filter Data Output
Register (FDOR)
A 24-bit-wide register used for EFCOP-to-DSP data transfers. Data is transferred to FDOR
after processing of all filter taps is completed for a specific set of input samples.
Filter K-Constant Input
Register (FKIR)
A 24-bit register for DSP-to-EFCOP constant transfers.
Filter Count (FCNT)
Register
A 24-bit register that specifies the number of filter taps. The count stored in the FCNT register
is used by the EFCOP address generation logic to generate correct addressing to the FDM and
FCM.
EFCOP Control Status
Register (FCSR)
A 24-bit read/write register used by the DSP56300 core to program the EFCOP and to examine
the status of the EFCOP module.
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Freescale Semiconductor
11-3
Enhanced Filter Coprocessor
Table 11-1. EFCOP Registers Accessible Through the PMB (Continued)
Register Name
Description
EFCOP ALU Control
Register (FACR)
A 24-bit read/write register used by the DSP56300 core to program the EFCOP data ALU
operating modes.
EFCOP Data Buffer Base
Address (FDBA)
A 16-bit read/write register used by the DSP56300 core to indicate the EFCOP the data buffer
base start address pointer in FDM RAM.
EFCOP Coefficient Buffer
Base Address (FCBA)
A 16-bit read/write register by which the DSP56300 core indicates the EFCOP coefficient buffer
base start address pointer in FCM RAM.
Decimation/
Channel Count Register
(FDCH)
A 24-bit register that sets the number of channels in multichannel mode and the filter
decimation ratio. The EFCOP address generation logic uses this information to supply the
correct addressing to the FDM and FCM.
11.2.2 EFCOP Memory Banks
The EFCOP contains two memory banks:
„
„
Note:
Filter Data Memory (FDM). This 24-bit-wide memory bank is mapped as X memory and
stores input data samples for EFCOP filter processing. The FDM is written via a 4-word
FIFO (FDIR), and its addressing is generated by the EFCOP address generation logic. The
input data samples are read sequentially from the FDM into the MAC. The FDM is
accessible for writes by the core, and the DMA controller and is shared with the 12 K
lowest locations ($0–$2FFF) of the on-chip internal X memory.
Filter Coefficient Memory (FCM). This 24-bit-wide memory bank is mapped as Y
memory and stores filter coefficients for EFCOP filter processing. The FCM is written via
the DSP56300 core, and the EFCOP address generation logic generates its addressing. The
filter coefficients are read sequentially from the FCM into the MAC. The FCM is
accessible for writes only by the core. The FCM is shared with the 12 K lowest locations
($0–$2FFF) of the on-chip internal Y memory.
The filter coefficients, H(n), are stored in “reverse order,” where H(N – 1) is stored at
the lowest address of the FCM register as shown in Figure 11-2.
Data
Memory
Bank
(FDM)
D(0)
H(N - 1)
D(1)
D(2)
D(3)
D(4)
D(5)
-
H(N - 2)
H(1)
Coefficient
Memory
Bank
(FCM)
H(0)
Figure 11-2. Storage of Filter Coefficients
DSP56321 Reference Manual, Rev. 1
11-4
Freescale Semiconductor
Architecture Overview
The EFCOP connects to the shared memory in place of the DMA bus. Simultaneous core and
EFCOP accesses to the same memory module block (1024 locations) of shared memory are not
permitted. It is your responsibility to prevent such simultaneous accesses. Figure 11-3 illustrates
the memory shared between the core and the EFCOP.
X RAM
Data
(FDM)
Y RAM
Coefficients
(FCM)
X RAM
Y RAM
P RAM
YDB
PDB
XDB
FDB
CDB
DDB
EFCOP
CORE
GDB
Figure 11-3. EFCOP Memory Organization
.
11.2.3 Filter Multiplier and Accumulator (FMAC)
The FMAC machine can perform a 24-bit × 24-bit multiplication with accumulation in a 56-bit
accumulator. The FMAC operates a pipeline: the multiplication is performed in one clock cycle,
and the accumulation occurs in the following clock cycle. Throughput is one MAC result per
clock cycle. The two MAC operands are read from the FDM and from the FCM. The full 56-bit
width of the accumulator is used for intermediate results during the filter calculations.
For operations with saturation mode disabled, the final result is rounded according to the selected
rounding mode and limited to the most positive number ($7FFFFF, if overflow occurred) or most
negative number ($800000, if underflow occurred) after processing of all filter taps is completed.
In saturation mode, the result is limited to the most positive number ($7FFFFF, if overflow
occurred), or the most negative number ($800000, if underflow occurred) after each MAC
operation. The 24-bit result from the FMAC is stored in the EFCOP output buffer, FDOR.
Operating in sixteen-bit arithmetic mode, the FMAC performs a 16-bit × 16-bit multiplication
with accumulation into a 40-bit accumulator. As with 24-bit operations, if saturation mode is
disabled, the result is rounded according to the selected rounding mode and limited to the most
positive number ($7FFF, if overflow occurred) or the most negative number ($8000, if underflow
occurred) after processing of all filter taps is completed. In saturation mode, the result is limited
to the most positive number ($7FFF, if overflow occurred) or the most negative number ($8000,
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Freescale Semiconductor
11-5
Enhanced Filter Coprocessor
if underflow occurred) after every MAC operation. The 16-bit result from the FMAC is stored in
the EFCOP output buffer, FDOR.
11.3 EFCOP Operation
DSP56L307 EFCOP operation is determined by the control bits in the EFCOP Control/Status
Register (FCSR), described in Section 11.4.5. Further filtering operations are enabled via the
appropriate bits in the FACR and FDCH registers. After the FCSR is configured to the mode of
choice, enable the EFCOP by setting FCSR[FEN].
Note:
To ensure proper EFCOP operation, most FCSR bits must be changed only while the
EFCOP is enabled.
Table 11-2 summarizes the EFCOP operating modes.
Table 11-2. EFCOP Operating Modes
FCSR Bits
Mode Description
3
3
6
FMLC
5–4
FOM
FUPD
EFCOP Disabled1
x
x
FIR, Real, single channel
0
FIR, Real, adaptive, single channel
2
FADP2
1
FLT
0
FEN
x
x
x
0
00
0
0
0
1
0
00
0
1
0
1
FIR, Real, coeff. update, single channel
0
00
1
0
0
1
FIR, Real, adaptive + coeff. update,
single channel
0
00
1
1
0
1
FIR, Real, multichannel
1
00
0
0
0
1
FIR, Real, adaptive, multichannel
1
00
0
1
0
1
FIR, Real, coeff. update, multichannel
1
00
1
0
0
1
FIR, Real, adaptive + coeff. update,
multichannel
1
00
1
1
0
1
FIR, Full Complex, single channel
0
01
0
0
0
1
FIR, Complex Alternating, single channel
0
10
0
0
0
1
FIR, Magnitude, single channel
0
11
0
0
0
1
IIR, Real, single channel
0
00
0
0
1
1
IIR, Real, multichannel
1
00
0
0
1
1
Notes: 1.
2.
3.
2
An x indicates that the specified value can be 1 or 0.
If the user sets the FUPD bit, the EFCOP updates the coefficients and clears the FUPD bit. The adaptive mode
(that is, FADP = 1) sets the FUPD bit, which causes the EFCOP to update the coefficients and then
automatically clear the FUPD bit. Therefore, the value assigned to the FUPD bit in this table refers only to its
initial setting and not its dynamic state during operation.
All bit combinations not defined by this table are reserved for future development.
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11-6
Freescale Semiconductor
EFCOP Operation
11.3.1 EFCOP Operation Summary
The EFCOP is very easy to use. To define the type of filtering to perform, you need only set the
following registers (the settings in the FDCH and FACR are optional) and then enable the
EFCOP by setting FCSR[FEN]:
„
„
„
„
FCNT
FDBA
FCBA
FCSR
Polling, DMA, or interrupts can then be used to write data to the FDIR and read data from the
FDOR. As Table 11-2 shows, the EFCOP operates in many different modes based on the settings
of the control registers. However, the EFCOP performs only two basic types of processing, FIR
filter type and IIR filter type processing. Various sub-options are available with each filter type,
as described in the following sections.
11.3.2 EFCOP Initialization
Before the first sample is processed, the EFCOP filter must be initialized; that is, the input
samples for times before n = 0 (assuming that time starts at 0) must be loaded into the FDM. The
method by which this is done depends on the Filter Type selected.
11.3.2.1 FIR Initialization
The number of samples needed to initialize the filter is the number of filter coefficients minus
one. To select Initialization mode, clear the FCSR[FPRC] bit. If FCSR[FPRC] is set,
initialization is disabled and the EFCOP assumes that the core wrote the initial input values to the
FDM before the EFCOP was enabled. Thus, the first value written to FDIR is the first sample to
be filtered.
If FCSR[FPRC] is clear, initialization mode is enabled and the EFCOP initializes the FDM by
receiving the number of coefficients minus one samples through the FDIR. After samples are
loaded, the next value written to the FDIR is the first sample to be filtered.
11.3.2.2 IIR Initialization
Initialization is always disabled with the IIR filter type, and the FCSR[FPRC] bit is ignored.
Thus, the DSP56300 core must write the initial input values before the EFCOP is enabled. The
first value written to FDIR is always the first sample to be filtered.
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Freescale Semiconductor
11-7
Enhanced Filter Coprocessor
11.3.3 FIR Filter Type
To select the FIR filter type clear FCSR[FLT] and perform the processing shown in Figure 11-4
based on the equation shown below. The EFCOP takes an input, x(n), from the FDIR, saves the
N
w(n ) =
∑ Bi x ( n – i )
i=0
input while shifting the previous inputs down in the FDM, multiplies each input in the FDM by
the corresponding coefficient, Bi, stored in the FCM, accumulates the multiplication results, and
places accumulation result, w(n), in the FDOR. This is done for each sample input to the FDIR.
FDIR
FDM
FCM
x(n)
B0
x(n – 1)
B1
x(n – 2)
B2
x(n – N)
BN
FDOR
Figure 11-4. FIR Filter Type Processing
11.3.3.1 FIR Operating Modes
There are four operating modes available with the FIR filter type:
„
„
„
„
Real
Complex
Alternating complex
Magnitude mode.
11.3.3.1.1 Real Mode
Real mode performs FIR type filtering with real data and is selected by clearing both FOM bits in
the FCSR. One sample, the real input, is written to the FDIR, and the EFCOP processes the data.
Then one sample, the real output, is read from the FDOR. Four options are available with the real
FIR filter type: coefficient update, adaptive mode, multichannel mode, and decimation. The first
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11-8
Freescale Semiconductor
EFCOP Operation
three options can be used individually or together. Decimation cannot be used with the adaptive
and multichannel mode options
11.3.3.1.2 Complex Mode
Complex mode performs FIR type filtering with complex data based on the following equations:
N–1
Re ( F ( n ) ) =
∑ Re ( H ( i ) ) ⋅ Re ( D ( n – i ) ) – Im ( H ( i ) ) ⋅ Im( D ( n – i ) )
i=0
N–1
Im ( F ( n ) ) =
∑ Re ( H ( i ) ) ⋅ Im ( D ( n – i ) ) + Im ( H( i) ) ⋅ Re ( D ( n – i ) )
i=0
where H(n) is the coefficients, D(n) is the input data, and F(n) is the output data at time n. Two
samples, the real part then the imaginary part of the input, are written to the FDIR. The EFCOP
processes the data, and then two samples—the real and then the imaginary part of the output—are
read from the FDOR.
Complex mode is selected by setting the FCSR[FOM] bits to 01. In Complex mode, the number
written to the FCNT register should be twice the number of filter coefficients. Also, the
coefficients are stored in the FCM with the real part of the coefficient in the memory location
preceding the memory location holding the imaginary part of the coefficient. Complex mode can
be used with the decimation option.
11.3.3.1.3 Alternating Complex Mode
Alternating Complex mode performs FIR type filtering with complex data, providing alternating
real and complex results based on the following equations
N–1
Re ( F ( n
even
)) =
∑ Re ( H ( i ) ) ⋅ Re( D ( n – i ) ) – Im ( H ( i ) ) ⋅ Im( D ( n – i ) )
i=0
N–1
Im ( F ( n
odd
)) =
∑ Re( H( i ) ) ⋅ Im ( D ( n – i ) ) + Im( H ( i ) ) ⋅ Re( D( n – i ) )
i=0
where H(n) is the coefficients, D(n) is the input data, and F(n) is the output data at time n. Two
samples, the real part then the imaginary part of the input, are written to the FDIR. The EFCOP
processes the data. Then one sample, alternating between the real part and the imaginary part of
the output, is read from the FDOR.
Alternating Complex mode is selected by setting the FCSR[FOM] bits to 10. In Alternating
Complex mode, the number written to the FCNT register should be twice the number of filter
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11-9
Enhanced Filter Coprocessor
coefficients. Also, the coefficients should be stored in the FCM with the real part of the
coefficient in the memory location preceding the memory location holding the imaginary part of
the coefficient. Alternating Complex mode can be used with the decimation option.
11.3.3.1.4 Magnitude Mode
Magnitude mode calculates the magnitude of an input signal based on the following equation:
N–1
F( n) =
∑ D(n – i)
2
i=0
where D(n) is the input data and F(n) is the output data at time n. One sample, the real input, is
written to the FDIR. The EFCOP processes the data. Then one sample, the real magnitude of the
input signal, is read from the FDOR. Magnitude mode is selected by setting both the
FCSR[FOM] bits. Magnitude mode can be used with the decimation option.
11.3.3.2 FIR Filter Type Processing Options
There are four processing option available for the FIR filter type:
„
„
„
„
Coefficient Update
Adaptive Mode
Multichannel Mode
Decimation
11.3.3.2.1 Coefficient Update Option
The Coefficient Update option is only available in Real operating mode. If the user sets the
FUPD bit, the EFCOP updates the coefficients and clears the FUPD bit. When used with adaptive
mode, this only sets the initial update, since the mode sets the FUPD bit dynamically during
normal operation to update the coefficients.
11.3.3.2.2 Adaptive Mode Option
Adaptive mode is only available in Real operating mode. It provides a way to update the
coefficients based on filter input, x(n), using the following equation,
h n + 1 ( i ) = hn ( i ) + Ke ( n ) x ( n – i )
where hn(i) is the ith coefficient at time n. The coefficients are updated when FSCR[FUPD] is
set. The EFCOP checks to see if a value has been written to the FKIR. If no value is written, the
EFCOP halts processing until a value is written to the FKIR. When a value is written to the
FKIR, the EFCOP updates all the coefficients based on the above equation using the value in the
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Freescale Semiconductor
EFCOP Operation
FKIR for Ke(n). The EFCOP automatically clears FSCR[FUPD] when the coefficient update is
complete.
If the coefficients are to be updated after every input sample, Adaptive mode is enabled by setting
the FCSR[FADP]. In Adaptive mode, the EFCOP automatically sets the FUDP bit after each
input sample is processed. This allows for continuous processing using interrupts that includes a
filter session and a coefficient update session with minimal core intervention.
11.3.3.2.3 Multichannel Mode Option
Multichannel mode is only available in Real operating mode. It allows several channels of data to
be processed concurrently and is selected by setting the FCSR[FMLC]. The number of channels
to process is one plus the number in the FDCH[FDCM] bits. For each time period, the EFCOP
expects to receive the samples for each channel sequentially. This is repeated for consecutive
time periods.
Filtering can be done with the same filter or different filters for each channel by using the
FCSR[FSCO] bit. If FCSR[FSCO] is set, the same set of coefficients are used for all channels. If
FSCO is clear, the coefficients for each filter are stored sequentially in memory for each channel.
11.3.3.2.4 Decimation Option
Decimation can be used with any four of the available FIR filter type modes. It cannot be used in
conjunction with Adaptive and Multichannel modes. Decimation decreases (downsamples) the
sampling rate. The decimation ratio defines the number of input samples per output sample. The
decimation ratio is one plus the number in the FDCH[FDCM] bits. The decimation ratio can be
programmed from 1 to 16.
For Real and Magnitude modes the decimation ratio number of samples must be written to the
FDIR before an output sample is read from the FDOR. For Complex mode, two times the
decimation ratio number of samples (one for the real part and one for the imaginary part of the
input) must be written to the FDIR before two output samples (one for the real part and one for
the imaginary part of the output) can be read from the FDOR. For Alternating Complex mode,
two times the decimation ratio number of samples must be written to the FDIR (one for the real
part and one for the imaginary part of the input) before one output sample (alternating between
the real part and the imaginary part of the output) can be read from the FDOR.
11.3.4 IIR Filter Type
To select the IIR filter type, set the FCSR[FLT] bit and perform the processing shown in Figure
11-5 based on the equation shown here. The EFCOP multiplies each previous output value in the
M
⎛
⎞
⎜
y ( n ) = S ⎜ w ( n ) + ∑ Aj y ( n – j )⎟⎟
⎝
⎠
j=1
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11-11
Enhanced Filter Coprocessor
FDM by the corresponding coefficient, A, stored in the FCM; accumulates the multiplication
results; adds the input, w(n), from the FDIR (which is optionally not scaled by S, depending on
the FACR[FISL] bit setting); places the accumulation result, y(n), in the FDOR; and saves the
output while shifting the previous outputs down in the FDM. This is done for each sample input
to the FDIR. To process a complete IIR filter, a FIR filter type session followed by an IIR filter
type session is needed.
FDM
y(n – 1)
FCM
A0
y(n – 2)
A1
y(n – 3)
A2
FDOR
FDIR
AN
y(n – N)
Figure 11-5. IIR Filter Type Processing
The IIR filter type only operates in Real mode. Thus, the FCSR[FOM] bits are ignored when the
IIR filter type is in use. Real mode performs IIR type filtering with real data. One sample, the real
input, is written to the FDIR, and the EFCOP processes the data. Then one sample, the real
output, is read from the FDOR.
The default operation is single-channel, but the user can also select the Multi-channel Mode
option. Multichannel mode for IIR filter type works exactly the same as it does for FIR filter
type, as explained in Section 11.3.3.2.3, Multichannel Mode Option, on page 11-11. The
Coefficient Update, Adaptive mode, and Decimation options are not available with the IIR filter
type.
11.3.5 EFCOP Data Transfer Examples
This section describes how to transfer data to and from the EFCOP using an FIR filter
configuration. Here, we provide background information to help you understand the examples in
Section 11.3.6, EFCOP Operation Examples, on page 11-14. The examples employ the
following notations:
„
„
D(n): Data sample at time n
H(n): Filter coefficient at time n
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Freescale Semiconductor
EFCOP Operation
„
„
„
F(n): Output result at time n
#filter_count: Number of coefficient values in the coefficient memory bank FCM; it is
equal to the initial value written to the FCNT register plus 1.
Compute: Perform all calculations to determine one filter output F(n) for a specific set of
input data samples
To transfer data to/from the EFCOP input/output registers, the Filter Data Input Register (FDIR)
and the Filter Data Output Register (FDOR) are triggered by three different methods:
„
„
„
Direct Memory Access (DMA)
Interrupts
Polling
Two FCSR bits (FDIBE and FDOBF) indicate the status of the FDIR and the FDOR,
respectively. All three data transfer methods use these two FCSR bits as their control mechanism.
If FDIBE is set, the input buffer is empty; if FDOBF is set, the output buffer is full. Because these
bits come into full operation only when the EFCOP is enabled (FCSR:FEN is set), the polling,
DMA, or interrupt methods can be initialized either before or after the EFCOP is enabled. No
service request is issued until the EFCOP is enabled, since FDIBE and FDOBF are cleared while
the EFCOP is in the Individual Reset state.
The most straightforward EFCOP data transfer method uses the core processor to poll the status
flags, monitoring for input/output service requests. The disadvantage of this approach is that it
demands large amounts of (if not all of) the core’s processing time. The interrupt and DMA
methods are more efficient in their use of the core processor. Interrupts intervene on the core
processor infrequently to service input/output data.
DMA can operate concurrently with the processor core and demands only minimal core resource
for setup. DMA transfers are recommended when the EFCOP is in FIR/IIR filtering mode since
the core can operate independently of the EFCOP while DMA transfers data to the FDIR and
from the FDOR. Since the EFCOP input buffer (FDIR) is four words deep, the DMA can input in
blocks of up to four words. A combination of DMA transfer for input and an interrupt request for
processing the output is recommended for adaptive FIR mode. This combination gives the
following benefits:
„
„
Input data transfers to the FDIR can occur independently of the core.
There is minimal intervention of the core while the weight update multiplier is updated.
If the initialization mode is enabled (that is, if the FCSR[FPRC] bit is cleared), the core can
initialize the coefficient bank while the DMA controller concurrently transfers initial data values
to the data bank. The EFCOP state machine starts computation as soon as #filter_count data
samples are input. If no initialization mode is used (the FCSR[FPRC] bit is set), the EFCOP starts
computation as soon as the first data sample is available in the input buffer. The filter coefficient
bank must therefore be initialized before an input data transfer starts. The DMA input channel
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11-13
Enhanced Filter Coprocessor
can continue transferring data whenever the input FIFO becomes empty, while the EFCOP state
machine takes data words from the FIFO whenever required.
11.3.6 EFCOP Operation Examples
The following sections provide examples of how to use the EFCOP in Real FIR Filter and
Adaptive FIR filter mode. Section 11.3.6.4, Verification for Filter Examples, on page 11-32 lists
the programming inputs and outputs for the examples in the following sections.
11.3.6.1 Real FIR Filter
In this example, an N tap FIR filter is represented as follows:
N–1
F(n) =
∑ H(i ) ⋅ D(n – i )
i=0
The filter is implemented with three different data transfers using the EFCOP in data
initialization mode:
1.
DMA input/DMA output.
2.
DMA input/polling output.
3.
DMA input/interrupt output.
This transfer combination is only one of many possible combinations.1
11.3.6.1.1 DMA Input/DMA Output
A 20-tap FIR filter using a 28-input sample signal is implemented in the following stages:
Set-up:
1.
Set the filter count register (FCNT) to the length of the filter coefficients –1
(that is, N – 1).
2.
Set the Data and Coefficient Base Address pointers (FDBA, FCBA).
3.
Set the operation mode (FCSR[5:4] = FOM[00]).
4.
Set Initialization mode (FCSR[7] = FPRC = 0).
1. For information on DMA transfers, refer to the Freescale application note entitled Using the DSP56300 Direct
Memory Access Controller (APR23/D).
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Freescale Semiconductor
EFCOP Operation
5.
Set DMA registers:
DMA input: A two-dimensional (2D) DMA transfer fills up the FDM bank via channel
0. The DMA input control registers are initialized as shown in Table 11-3.
Table 11-3. DMA Channel 0 Register Initialization
Register Setting
DCR0 bit values are as follows:
Description
DMA Control Register 0
DIE = 0
Disables end-of-transfer interrupt.
DTM = 2
Chooses line transfer triggered by request; DE
auto clear on end of transfer.
DPR = 2
Priority 2
DCON = 0
Disables continuous mode.
DRS = $15
Chooses DMA to trigger on EFCOP input buffer
empty.
D3D = 0
Chooses non-3D mode.
DAM = $20
Sets the following DMA Address Mode:
− source address - 2D
− counter mode B
− offset DOR0
− destination address - no update, no
offset
DDS = 1
Destination in Y memory space (because the
EFCOP is in Y memory).
DSS = 0
Source in X memory space.
DOR0=1
DMA Offset Register 0
DCO0= $006003
DMA Counter Register 0
Gives transfer of 7 * 4 = 28 items (input sequence
length).
DSR0 = Address of source data
DMA Source Address Register 0
DDR0 = $FFFFB0
DMA Destination Address Register for Channel 0
DMA output: Channel 1 is used, with a configuration similar to that of the DMA input
channel, except for a 1D transfer. The DMA output control registers are initialized as
shown in Table 11-4.
Table 11-4. DMA Channel 1 Register Initialization
Register Setting
DCR1 bit values are as follows:
Description
DMA Control Register 1
DIE = 0
Disables end-of-transfer interrupt.
DTM = 1
Chooses word transfer triggered by request, DE
auto clear on end of transfer.
DPR = 3
Priority 3.
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Enhanced Filter Coprocessor
Table 11-4. DMA Channel 1 Register Initialization (Continued)
Register Setting
Description
DCON = 0
Disables continuous mode.
DRS = $16
Chooses DMA to trigger on EFCOP output buffer
full.
D3D = 0
Chooses non-3D mode.
DAM = $2C
Sets the following DMA address mode
source address - no update, no offset
destination address - 1D, post-increment by
1, no offset.
DDS = 0
Destination in X memory space.
DSS = 1
Source in Y memory space (because EFCOP is in
Y memory).
„
„
DCO1 = $12
DMA Counter Register 1: Gives transfer of 9 items.
DSR1 = address of FDOR = $FFFFFB1
DMA Source Address Register 1
DDR1 = address of destination memory
space
DMA Destination Address Register 1
Setting the DCO0 and DCO1 must be considered carefully. These registers must be
loaded with one less than the number of items to be transferred. Also, the following
equality must hold: DCO1=input length - filter length.
6.
Initialization:
7.
• Enable DMA channel 1 (output) DCR1[23] DE=1
• Enable EFCOP FCSR[0] FEN=1
• Enable DMA channel 0. (input) DCR0[23] DE=1
Processing:
•
•
Whenever the Input Data Buffer (FDIR) is empty (that is, FDIBE = 1), the EFCOP
triggers DMA input to transfer up to four new data words to FDIR.
Compute F(n); The result is stored in FDOR, and this triggers the DMA for an
output data transfer.
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Freescale Semiconductor
EFCOP Operation
The filter coefficients are stored in “reverse order,” as Figure 11-6 shows.
D(0)
Data
Memory
Bank
(FDM)
D(1)
D(2)
D(3)
D(4)
D(5)
-
H(N - 1)
Output Data
Stream
F(0)
F(1)
F(2)
F(3)
F(4)
F(5)
-
H(N - 2)
H(1)
H(0)
Coefficient
Memory
Bank
(FCM)
Figure 11-6. Real FIR Filter Data Stream
Example 11-1. Real FIR Filter Using DMA Input/DMA Output
INCLUDE ’ioequ.asm’
;;******************************************************************
; equates
;;******************************************************************
Start equ$00100
FCON
; main program starting address
equ
$001
; EFCOP FSCR register contents:
; enable the EFCOP
FIR_LEN
equ
20
SRC_ADDRS
equ
$3040; ; DMA source address point to DATA bank
DST_ADDRS
equ
$3000; address at which to begin output
SRC_COUNT
equ
$006003 ; DMA0 count (7*4 word transfers)
DST_COUNT
FDBA_ADDRS
FCBA_ADDRS
equ
equ
equ
8
; EFCOP FIR length
; number of outputs generated.
0 ; Input samples Start Address x:$0
0 ; Coeff. Start Address y:$0
;;******************************************************************
; main program
;;******************************************************************
ORG p:Start
move#FDBA_ADDRS,r0 ; FDM memory area
move#0,x0
rep #DST_COUNT
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Freescale Semiconductor
11-17
Enhanced Filter Coprocessor
movex0,x:(r0)+
; clear FDM memory area
; ** DMA channel 1 initialization
- output from EFCOP **
movep
#M_FDOR,x:M_DSR1
; DMA source address points to the EFCOP FDIR
movep
#DST_ADDRS,x:M_DDR1 ; Init DMA destination address.
movep
#DST_COUNT,x:M_DCO1 ; Init DMA count.
movep
#$8EB2C1,x:M_DCR1 ; Start DMA 1 with FDOBF request.
; ** EFCOP initialization **
movep
#FIR_LEN-1,y:M_FCNT ; FIR length
movep
#FDBA_ADDRS,y:M_FDBA ; FIR input samples Start Address
movep
#FCBA_ADDRS,y:M_FCBA ; FIR Coeff. Start Address
movep
#FCON,y:M_FCSR ; Enable EFCOP
; ** DMA channel 0 initialization - input to EFCOP **
movep
movep
#SRC_ADDRS,x:M_DSR0 ; DMA source address points to the DATA bank.
#M_FDIR,x:M_DDR0 ; Init DMA destination address.
movep
#SRC_COUNT,x:M_DCO0 ; Init DMA count to line mode.
movep
#$1,x:M_DOR0 ; DMA offset reg. is 1.
movep
#$94AA04,x:M_DCR0 ; Init DMA control reg to line mode FDIBE request.
nop
nop
;;******************************************************************
jclr #0,x:M_DSTR,*
jclr #1,x:M_DSTR,*
nop
nop
stop_label
nop
jmp stop_label
org x:SRC_ADDRS
INCLUDE ‘input.asm’
org y:FCBA_ADDRS
INCLUDE ‘coefs.asm’
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Freescale Semiconductor
EFCOP Operation
11.3.6.1.2 DMA Input/Polling Output
The different stages of input/polling are as follows:
1.
Set up:
•
2.
Set the filter count register (FCNT) to the length of the filter coefficients – 1 (that
is, N – 1).
• Set the data and coefficient base address pointers (FDBA, FCBA).
• Set the operation mode (FCSR[5:4] = FOM[00]), = 1).
• Set the initialization mode (FCSR[7] = FPRC = 0).
• Set DMA registers: DMA input: as per channel 0 in Section 11.3.6.1.1
Initialization:
3.
• Enable EFCOP FCSR[0] FEN=1.
• Enable DMA input channel, DCR0[23] DE=1.
Processing:
•
•
•
Whenever the Input Data Buffer (FDIR) is empty (that is, FDIBE = 1), the EFCOP
triggers DMA input to transfer up to four new data words to FDM via FDIR.
Compute F(n); the result is stored in FDOR.
The core keeps polling the FCSR[FDOBF] bit and stores the data in memory.
Example 11-2. Real FIR Filtering using DMA input/Polling output
INCLUDE ’ioequ.asm’
;;******************************************************************
; equates
;;******************************************************************
Startequ$00100; main program starting address
FCON
equ
$001 ; EFCOP FSCR register contents:
; enable the EFCOP
FIR_LEN
equ
20 ; EFCOP FIR length
SRC_ADDRS
equ
$3040; DMA source address point to DATA bank
DST_ADDRS
equ
$3000; address at which to begin output
SRC_COUNT
equ
$006003 ; DMA0 count (7*4 word transfers)
DST_COUNT
equ
8
FDBA_ADDRS
equ
0 ; Input samples Start Address x:$0
FCBA_ADDRS
equ
0 ; Coeff. Start Address y:$0
; number of outputs generated.
;;******************************************************************
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Freescale Semiconductor
11-19
Enhanced Filter Coprocessor
; main program
;;******************************************************************
ORG p:Start
move
#0,b
move
#0,a
move
#DST_COUNT,b0 ; counter for output interrupt
move#FDBA_ADDRS,r0 ; FDM memory area
move#0,x0
rep #DST_COUNT
movex0,x:(r0)+
move
; clear FDM memory area
#DST_ADDRS,r0 ; Destination address
; ** EFCOP initialization **
movep
#FIR_LEN-1,y:M_FCNT ; FIR length
movep
#FDBA_ADDRS,y:M_FDBA ; FIR input samples Start Address
movep
#FCBA_ADDRS,y:M_FCBA ; FIR Coeff. Start Address
movep
#FCON,y:M_FCSR ; Enable EFCOP
; ** DMA channel 0 initialization - input to EFCOP **
movep
#SRC_ADDRS,x:M_DSR0 ; DMA source address points to the DATA bank.
movep
#M_FDIR,x:M_DDR0 ; Init DMA destination address.
movep
#SRC_COUNT,x:M_DCO0 ; Init DMA count to line mode.
movep
#$1,x:M_DOR0 ; DMA offset reg. is 1.
movep
#$94AA04,x:M_DCR0 ; Init DMA control reg to line mode FDIBE request.
nop
nop
;;******************************************************************
do
#DST_COUNT,endd
nop
jclr #15,y:M_FCSR,*
movep y:M_FDOR,x:(r0)+
endd
nop
nop
stop_label
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Freescale Semiconductor
EFCOP Operation
nop
jmp stop_label
org x:SRC_ADDRS
INCLUDE ‘input.asm’
org y:FCBA_ADDRS
INCLUDE ‘coefs.asm’
11.3.6.1.3 DMA Input/Interrupt Output
The different stages of DMA input and interrupt output are as follows:
1.
Set up:
•
2.
Set the filter count register (FCNT) to the length of the filter coefficients –1 (that is,
N – 1).
• Set the Data and Coefficient Base Address pointers (FDBA, FCBA).
• Set the operation mode (FCSR[5:4] = FOM[00],).
• Set Initialization mode (FCSR[7] = FPRC = 0).
• Set Filter Data Output Interrupt Enable FSCR[11]=FDOIE=1.
• Set DMA register with DMA input as per channel 0 in Section 11.3.6.1.1.
Initialization:
3.
• Enable interrupts in the Interrupt Priority Register IPRP[10:11]=E0L=11.
• Enable interrupts in the Status Register SR[8:9]=00.
• Enable EFCOP FCSR[0]=FEN=1.
• Enable the DMA input channel, DCR0[23]=DE=1.
Processing:
•
•
Whenever the Input Data Buffer (FDIR) is empty (that is, FDIBE = 1), the EFCOP
triggers DMA, which loads the next input into the FDIR.
Compute F(n); the result is stored in FDOR; The core is interrupted when FDOBF
is set and stores the data in memory.
Example 11-3. Real FIR Filter DMA Input/Interrupt Output
INCLUDE ’ioequ.asm’
;;******************************************************************
; equates
;;******************************************************************
Startequ$00100; main program starting address
FCON equ
$801 ; EFCOP FSCR register contents:
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Freescale Semiconductor
11-21
Enhanced Filter Coprocessor
; enable output interrupt
; enable the EFCOP
FIR_LEN equ
20 ; EFCOP FIR length
SRC_ADDRS equ
DST_ADDRS equ
$3040; DMA source address point to DATA bank
$3000 ; address at which to begin output
SRC_COUNT equ
$006003 ; DMA0 count (7*4 word transfers)
DST_COUNT equ
8; number of outputs generated.
FDBA_ADDRS equ
0 ; Input samples Start Address x:$0
FCBA_ADDRS equ
0 ; Coeff. Start Address y:$0
;;******************************************************************
org P:$0
jmpStart
ORG p:$6a
jsr
>kdo
nop
nop
;;******************************************************************
; main program
;;******************************************************************
ORG p:Start
; ** interrupt initialization **
bset
#10,x:M_IPRP ;
bset
#11,x:M_IPRP ; enable EFCOP interrupts in IPRP
bclr
#8,SR
;
bclr
#9,SR
; enable interrupts in SR
move
#0,b
move
#0,a
move
#DST_COUNT,b0 ; counter for output interrupt
move#FDBA_ADDRS,r0 ; FDM memory area
move#0,x0
rep #DST_COUNT
movex0,x:(r0)+
move
; clear FDM memory area
#DST_ADDRS,r0 ; Destination address
; ** EFCOP initialization **
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Freescale Semiconductor
EFCOP Operation
movep
#FIR_LEN-1,y:M_FCNT ; FIR length
movep
#FDBA_ADDRS,y:M_FDBA ; FIR input samples Start Address
movep
movep
#FCBA_ADDRS,y:M_FCBA ; FIR Coeff. Start Address
#FCON,y:M_FCSR ; Enable EFCOP
; ** DMA channel 0 initialization - input to EFCOP **
movep
#SRC_ADDRS,x:M_DSR0 ; DMA source address points to the DATA bank.
movep
#M_FDIR,x:M_DDR0 ; Init DMA destination address.
movep
#SRC_COUNT,x:M_DCO0 ; Init DMA count to line mode.
movep
#$1,x:M_DOR0 ; DMA offset reg. is 1.
movep
#$94AA04,x:M_DCR0 ; Init DMA control reg to line mode FDIBE request.
nop
nop
;;******************************************************************
wait1
jset
do
#11,y:M_FCSR,*
; Wait until FDOIE is cleared.
#40,endd
nop
endd
nop
nop
stop_label
nop
jmp stop_label
;;******************************************************************
kdo
; Interrupt handler for EFCOP output
movep
y:M_FDOR,x:(r0)+ ; Get y(k) from FDOR
; Store in destination memory space.
nop
dec b
jne cont
nop
bclr
#11,y:M_FCSR
; Disable output interrupt
cont
rti
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Enhanced Filter Coprocessor
nop
nop
nop
org x:SRC_ADDRS
INCLUDE‘input.asm’
org y:FCBA_ADDRS
INCLUDE ‘coefs.asm’
11.3.6.2 Real FIR Filter With Decimation by M
An N tap real FIR filter with decimation by M of a sequence of real numbers is represented by,
N–1
F(n
) =
M
∑ H(i) ⋅ D(n – i)
i=0
A DMA data transfer occurs in the following stages for both input and output.The stages are the
similar to the ones described in Section 11.3.6.1.1. The difference is: set FDCH[11:8] = FDCM
=M.
Processing:
1.
Whenever the Input Data Buffer (FDIR) is empty (that is, FDIBE = 1), the EFCOP
triggers DMA input to transfer up to four new data words to FDM via FDIR.
2.
Compute F(n); the result is stored in FDOR; the EFCOP triggers DMA output for an
output data transfer.
3.
Repeat M times:
{
Get new data word; EFCOP increments data memory pointer.}
D(0)
Data
Memory
Bank
(FDM)
D(1)
D(2)
D(3)
D(4)
D(5)
-
H(N - 1)
Output Data
Stream
F(0)
F(M)
F(2M)
F(3M)
F(4M)
-
H(N - 2)
H(1)
H(0)
Coefficient
Memory
Bank
(FCM)
Figure 11-7. Real FIR Filter Data Stream With Decimation by M
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EFCOP Operation
11.3.6.3 Adaptive FIR Filter
An adaptive FIR filter is represented in Figure 11-8. The goal of the FIR filter is to adjust the
filter coefficients so that the output, F(n), becomes as close as possible to the desired signal,
R(n)—that is, E(n) -> 0.
R(n)
D(n)
Adaptive
FIR Filter
F(n)
Filter Update
E(n)
Figure 11-8. Adaptive FIR Filter
The adaptive FIR filter typically comprises four stages, which are performed for each input
sample at time n:
„
Stage 1. The FIR filter output value is calculated for the EFCOP FIR session according to
this equation:
N–1
F( n) =
∑ Hn( i)D( n – i)
i=0
„
where Hn(i) are the filter coefficients at time n, D(n) is the input signal and F(n) is the
filter output at time n. This stage requires N MAC operations, calculated by the EFCOP
FMAC unit.
Stage 2. The core calculates the error signal, E(n), in software according to the following
equation:
E( n ) = R(n ) – F( n)
„
where R(n) is the desired signal at time n. This stage requires a single arithmetic operation.
Stage 3. The core calculates the weight multiplier, Ke(n), in software according to the
following equation:
Ke(n) = K * E(n)
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Enhanced Filter Coprocessor
„
where K is the convergence factor of the algorithm. After calculating the weight
multiplier, Ke, the core must write it into the FKIR.
Stage 4. The coefficients are updated by the EFCOP update session:
H n + 1 ( i ) = H n ( i ) + Ke D ( n – i )
where Hn+1(i) are the adaptive filter coefficients at time n+1, Ke(n) is the weight
multiplier at time n, and D(n) is the input signal. This stage starts immediately after Ke(n)
is written in the FKIR (if Adaptive mode is enabled).
11.3.6.3.1 Implementation Using Polling
Figure 11-9 shows a flowchart for an adaptive FIR filter that uses polling to transfer data.
Start
Set FCNT = N – 1
Set FDBA, FCBA
Calculate K e
Enable EFCOP
(ADP) Real FIR Mode
Write Ke to FKIR
Write next x(n)
Set FUPD = 1
No
(opt.)
Automatically
Done in ADP Mode
Output Buffer
Full?
Yes
Read y(n)
Block
Done?
No
Yes
End
Figure 11-9. Adaptive FIR Filter Using Polling
DSP56321 Reference Manual, Rev. 1
11-26
Freescale Semiconductor
EFCOP Operation
11.3.6.3.2 Implementation Using DMA Input and Interrupt Output
Figure 11-10 shows a flowchart for an adaptive FIR filter that uses DMA and an interrupt to
transfer data.
Start
Output Buffer
Full
Interrupt
Set DMA/Int for input
on FDIBE
Set FCNT=L-1
Set FDBA, FCBA
Read y(n)
Enable EFCOP
ADP Real FIR Mode
Calculate K e
No
Block
Done?
Write Ke to FKIR
Yes
Set FUPD = 1
End
(opt.)
Automatically
Done in ADP Mode
RTI
Figure 11-10. Adaptive FIR Filter Using DMA Input and Interrupt Output
11.3.6.3.3 Updating an FIR Filter
The following example shows an FIR adaptive filter that is updated using the LMS algorithm.
Example 11-4. FIR Adaptive Filter Update Using the LMS Algorithm
TITLE ’ADAPTIVE’
INCLUDE ’ioequ.asm’
;;************************************************************************************
; equates
;;************************************************************************************
Start
equ
$00100
; main program starting address
FCON
equ
$805
; EFCOP FSCR register contents:
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-27
Enhanced Filter Coprocessor
; enable output interrupt
; Choose adaptive real FIR mode
; enable the EFCOP
FIR_LEN
equ
20
; EFCOP FIR length
DES_ADDRS
equ
$3200
; Desired signal R(n)
SRC_ADDRS
equ
$3100
; Reference signal D(n)
DST_ADDRS
equ
$3000
; address at which to begin output (signal F(n))
SRC_COUNT
equ
$06003
; DMA0 count (7*4 word transfers)
DST_COUNT
equ
8
; number of outputs generated.
MU2
equ
$100000
; stepsize mu = 0.0625 (that is 2mu = 0.125)
FDBA_ADDRS
equ
0
; Input samples Start Address x:$0
FCBA_ADDRS
equ
0
; Coeff. Start Address y:$0
;;************************************************************************************
org p:$0
jmp
Start
ORG p:$6a
jsr
>kdo
nop
nop
;;************************************************************************************
; main program
;;************************************************************************************
ORG p:Start
; ** interrupt initialization **
bset
#10,x:M_IPRP
;
bset
#11,x:M_IPRP
; enable EFCOP interrupts in IPRP
bclr
#8,SR
;
bclr
#9,SR
; enable interrupts in SR
DSP56321 Reference Manual, Rev. 1
11-28
Freescale Semiconductor
EFCOP Operation
move
#0,b
move
#0,a
move
#DST_COUNT,b0
; counter for output interrupt
; ** FDM memory initialization **
move
#FDBA_ADDRS,r0
move
#0,x0
rep
#FIR_LEN
move
x0,x:(r0)+
; FDM memory area
; clear FDM memory area
; ** address register initialization **
move
#DST_ADDRS,r0
; Destination address
move
#DES_ADDRS,r1
; Desired signal address
rep
#FIR_LEN-1
move
(r1)+
; Set reference pointer correctly
; ** EFCOP initialization **
movep
#FIR_LEN-1,y:M_FCNT
; FIR length
movep
#FDBA_ADDRS,y:M_FDBA
; FIR input samples Start Address
movep
#FCBA_ADDRS,y:M_FCBA
; FIR Coeff. Start Address
movep
#FCON,y:M_FCSR
; Enable EFCOP
; ** DMA channel 0 initialization - input to EFCOP **
movep
#SRC_ADDRS,x:M_DSR0
; DMA source address points to the DATA bank.
movep
#M_FDIR,x:M_DDR0
; Init DMA destination address.
movep
#SRC_COUNT,x:M_DCO0
; Init DMA count to line mode.
movep
#$1,x:M_DOR0
; DMA offset reg. is 1.
movep
#$94AA04,x:M_DCR0
; Init DMA control reg to line mode FDIBE request.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-29
Enhanced Filter Coprocessor
nop
nop
;;******************************************************************
wait1
jset
#11,y:M_FCSR,*
do
#40,endd
; Wait until FDOIE is cleared.
nop
endd
nop
nop
stop_label
nop
jmp stop_label
;;******************************************************************
kdo
; Interrupt handler for EFCOP output
movep
y:M_FDOR,x:(r0)
; Get F(n) from FDOR
; Store in destination memory space.
;******* Calculate Ke *********
move
x:(r1)+,a
; Retrieve desired value R(n)
move
x:(r0)+,y0
;
sub
y0,a
; calculate E(n) = R(n) - F(n)
move
#MU2,y0
;
move
a,y1
;
mpy
y0,y1,a
; calculate Ke = mu * 2 * E(n)
;******************************
movepa1,y:M_FKIR
; store Ke in FKIR
DSP56321 Reference Manual, Rev. 1
11-30
Freescale Semiconductor
EFCOP Operation
dec
b
jne
cont
nop
bclr
#11,y:M_FCSR
; Disable output interrupt
cont
rti
nop
nop
nop
;;******************************************************************
;;******************************************************************
ORG y:FCBA_ADDRS
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
dc
$000000
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-31
Enhanced Filter Coprocessor
ORG x:SRC_ADDRS
INCLUDE ’input.asm’; Reference signal D(n)
ORG x:DES_ADDRS
INCLUDE ’desired.asm’; Desired signal R(n)
11.3.6.4 Verification for Filter Examples
The following sections provide input and output program listings for the examples given in
Section 11.3.6.1 through Section 11.3.6.3.
11.3.6.4.1 Input Sequence (input.asm)
dc
$000000
dc
$37cc8a
dc
$343fae
dc
$0b63b1
dc
$0595b4
dc
$38f46e
dc
$6a4ea2
dc
$5e8562
dc
$2beda5
dc
$1b3cd0
dc
$42f452
dc
$684ca0
dc
$5093b0
dc
$128ab8
dc
$f74ee1
dc
$15c13a
dc
$336e48
dc
$15e98e
dc
$d428d2
dc
$b76af5
dc
$d69eb3
dc
$f749b6
dc
$dee460
DSP56321 Reference Manual, Rev. 1
11-32
Freescale Semiconductor
EFCOP Operation
dc
$a43601
dc
$903d59
dc
$b9999a
dc
$e5744e
11.3.6.4.2 Filter Coefficients (coefs.asm)
dc $F8125C
dc $F77839
dc $F4E9EE
dc $F29373
dc $F2DC9A
dc $F51D6E
dc $F688CE
dc $F6087E
dc $F5B5D3
dc $F7E65E
dc $FBE0F8
dc $FEC8B7
dc $FF79F5
dc $000342
dc $02B24F
dc $06C977
dc $096ADD
dc $097556
dc $08FD54
dc $0A59A5
11.3.6.4.3 Output Sequence for Examples 11-1, 11-2, and 11-3
$d69ea9
$ccae36
$c48f2a
$be8b28
$bad8c5
$b9998c
$bad8cb
$be8b2d
$c7b906
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-33
Enhanced Filter Coprocessor
11.3.6.4.4 Desired Signal for Example 11-4
dc
$000000
dc
$0D310F
dc
$19EA7C
dc
$25B8E2
dc
$30312E
dc
$38F46D
dc
$3FB327
dc
$443031
dc
$4642D6
dc
$45D849
dc
$42F452
dc
$3DB126
dc
$363E7F
dc
$2CDFE8
dc
$21EA5B
dc
$15C13A
dc
$08D2CE
dc
$FB945D
dc
$EE7E02
dc
$E2066F
dc
$D69EB2
dc
$CCAE3C
dc
$C48F2F
dc
$BE8B32
dc
$BAD8D3
dc
$B99999
dc
$BAD8D3
dc
$BE8B32
11.3.6.4.5 Output Sequence for Example 11-4
$000000
$f44c4c
$ee54b3
$e7cd6b
$daed26
DSP56321 Reference Manual, Rev. 1
11-34
Freescale Semiconductor
EFCOP Programming Model
$cc1071
$c7db1c
$cdfe45
11.4 EFCOP Programming Model
This section documents the registers for configuring and operating the EFCOP. The EFCOP
registers available to the DSP programmer are listed in Table 11-5. The following paragraphs
describe these registers in detail.
Table 11-5. EFCOP Registers and Base Addresses
Address
EFCOP Register Name
Y:$FFFFB0
Filter data input register (FDIR)
Y:$FFFFB1
Filter data output register (FDOR)
Y:$FFFFB2
Filter K-constant register (FKIR)
Y:$FFFFB3
Filter count register (FCNT)
Y:$FFFFB4
Filter control status register (FCSR)
Y:$FFFFB5
Filter ALU control register (FACR)
Y:$FFFFB6
Filter data buffer base address (FDBA)
Y:$FFFFB7
Filter coefficient base address (FCBA)
Y:$FFFFB8
Filter decimation/channel register (FDCH)
Note: The EFCOP registers are mapped onto Y data memory space.
11.4.1 Filter Data Input Register (FDIR)
The FDIR is a 4-word deep, 24-bit wide FIFO for DSP-to-EFCOP data transfers. Up to four data
samples can be written into the FDIR at the same address. Data from the FDIR is transferred to
the FDM for filter processing. For proper operation, write data to the FDIR only if the FDIBE
status bit is set, indicating that the FIFO is empty. A write to the FDIR clears the FDIBE bit. Data
transfers can be triggered by an interrupt request (for core transfers) or a DMA request (for DMA
transfers). The FDIR is accessible for writes by the DSP56300 core and the DMA controller.
11.4.2 Filter Data Output Register (FDOR)
The FDOR is a 24-bit read-only register for EFCOP-to-DSP data transfers. The result of the filter
processing is transferred from the FMAC to the FDOR. For proper operation, read data from the
FDOR only if the FDOBF status bit is set, indicating that the FDOR contains data. A read from
the FDOR clears the FDOBF bit. Data transfers can be triggered by an interrupt request (for core
transfers) or a DMA request (DMA transfers). The FDOR is accessible for reads by the
DSP56300 core and the DMA controller.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-35
Enhanced Filter Coprocessor
11.4.3 Filter K-Constant Input Register (FKIR)
The Filter K-Constant Input Register (FKIR) is a 24-bit write-only register for DSP-to-EFCOP
data transfers in adaptive mode where the value stored in FKIR represents the weight update
multiplier. FKIR is accessible only to the DSP core for reads or writes. When adaptive mode is
enabled, the EFCOP immediately starts the coefficient update if a K-Constant value is written to
FKIR. If no value is written to FKIR for the current data sample, the EFCOP halts processing
until the K-Constant is written to FKIR. After the weight update multiplier is written to FKIR, the
EFCOP transfers it to the FMAC unit and starts updating the filter coefficients according to the
following equation:
New_coefficients = Old_coefficients + FKIR * Input_buffer
11.4.4 Filter Count (FCNT) Register
The FCNT register is a read/write register that selects the filter length (number of filter taps).
Always write the initial count into the FCNT register before you enable the EFCOP (that is,
before you set FEN). The number stored in FCNT is used to generate the correct addressing for
the FDM and for the FCM.
Note:
To ensure correct operation, never change the contents of the FCNT register unless the
EFCOP is in the individual reset state (that is, FEN = 0). In the individual reset state
(that is, FEN = 0), the EFCOP module is inactive, but the contents of the FCNT
register are preserved.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
FCNT9
FCNT8
FCNT7
FCNT6
FCNT5
FCNT4
FCNT3
FCNT2
FCNT1
FCNT0
FCNT11 FCNT10
=
Reserved bit; read as 0; write with 0 for future compatibility
Table 11-6. Filter Count FCNT Register Bits
Bit #
Abbr.
23–12
11–0
Description
These bits are reserved and unused. They read as 0; write with 0 for future compatibility.
FCNT
Filter Count
The actual value written to the FCNT register must be the number of coefficient values minus one.
The number of coefficient values is the number of locations used in the FCM. For a real FIR filter, the
number of coefficient values is identical to the number of filter taps. For a complex FIR filter, the
number of coefficient values is twice the number of filter taps.
DSP56321 Reference Manual, Rev. 1
11-36
Freescale Semiconductor
EFCOP Programming Model
11.4.5 EFCOP Control Status Register (FCSR)
The FCSR is a read/write register by which the DSP56300 core controls the main operation
modes of the EFCOP and monitors the EFCOP status.
23
22
11
10
FDOIE
FDIIE
=
21
20
9
19
18
17
16
15
14
13
12
FDOBF
FDIBE
FCONT
FSAT
8
7
6
5
4
3
2
1
0
FSCO
FPRC
FMLC
FOM1
FOM0
FUPD
FADP
FLT
FEN
Reserved bit; read as 0; write with 0 for future compatibility
Table 11-7. FCSR Bits
Bit
Number
Bit Name
23–16
Reset
Value
Description
0
These bits are reserved and unused. They read as 0; write with 0 for future
compatibility.
15
FDOBF
0
Filter Data Output Buffer Full
When set, this read-only status bit indicates that the FDOR is full and the DSP can
read data from the FDOR. The FDOBF bit is set when a result from FMAC is
transferred to the FDOR. For proper operation, read data from the FDOR only if the
FDOBF status bit is set. When FDOBF is set, the EFCOP generates an FDOBF
interrupt request to the DSP56300 core if that interrupt is enabled (that is,
FDOIE = 1). A DMA request is always generated when the FDOBF bit is set, but a
DMA transfer takes place only if a DMA channel is activated and triggered by this
event. A read from the FDOR clears the FDOBF bit.
14
FDIBE
0
Filter Data Input Buffer Empty
When set, this read-only status bit indicates that the FDIR is empty and the DSP can
write data to the FDIR. The FDIBE bit is set when all four FDIR locations are empty.
For proper operation, write data to the FDIR only if FDIBE is set. After the EFCOP is
enabled by setting FEN, FDIBE is set, indicating that the FDIR is empty. When FDIBE
is set, the EFCOP generates an FDIR empty interrupt request to the DSP56300 core,
if enabled (that is, FDIIE = 1). A DMA request is always generated when the FDIBE
bit is set, but a DMA transfer takes place only if a DMA channel is activated and
triggered by this event. A write to the FDIR clears the FDIBE bit.
13
FCONT
0
Filter Contention
When set, this read-only status bit indicates an attempt by both the DSP56300 core
and the EFCOP to access the same 1024-word bank in either the shared FDM or
FCM. A dual access could result in faulty data output in the FDOR. Once set, the
FCONT bit is a sticky bit that can only be cleared by a hardware RESET signal, a
software RESET instruction, or an individual reset.
12
FSAT
0
Filter Saturation
When set, this read-only status bit indicates that an overflow or underflow occurred in
the MAC result. When an overflow occurs, the FSAT bit is set, and the result is
saturated to the most positive number (that is, $7FFFFF). When an underflow occurs,
the FSAT bit is set, and the result is saturated to the most negative number (that is,
$800000). FSAT is a sticky status bit that is set by hardware and can be cleared only
by a hardware RESET signal, a software RESET instruction, or an individual reset.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-37
Enhanced Filter Coprocessor
Table 11-7. FCSR Bits (Continued)
Bit
Number
Bit Name
Reset
Value
11
FDOIE
0
Filter Data Output Interrupt Enable
This read/write control bit enables the filter data output interrupt. If FDOIE is cleared,
the filter data output interrupt is disabled, and the FDOBF status bit should be polled
to determine whether the FDOR is full. If both FDOIE and FDOBF are set, the EFCOP
requests a data output buffer full interrupt service from the DSP56300 core. A DMA
transfer is enabled if a DMA channel is activated and triggered by this event. For
proper operation, enable the interrupt service routine and the corresponding interrupt
for core processing or enable the DMA transfer and configure the proper trigger for
the selected channel. Never enable both simultaneously.
10
FDIIE
0
Filter Data Input Interrupt Enable
This read/write control bit enables the data input buffer empty interrupt. If FDIIE is
cleared, the data input buffer empty interrupt is disabled, and the FDIBE status bit
should be polled to determine whether the FDIR is empty. If both FDIIE and FDIBE
are set, the EFCOP requests a data input buffer empty interrupt service from the
DSP56300 core. DMA transfer is enabled if a DMA channel is activated and triggered
by this event. For proper operation, enable the interrupt service routine and the
corresponding interrupt for core processing or enable the DMA transfer and configure
the proper trigger for the selected channel. Never enable both simultaneously.
0
Reserved. It is read as 0 and write with 0 for future compatibility.
9
Description
8
FSCO
0
Filter Shared Coefficients Mode
This read/write control bit is valid only when the EFCOP is operating in multichannel
mode (that is, FMLC is set). When FSCO is set, the EFCOP uses the coefficients in
the same memory area (that is, the same coefficients) to implement the filter for each
channel. This mode is used when several channels are filtered through the same
filter. When the FSCO bit is cleared, the EFCOP filter coefficients are stored
sequentially in memory for each channel. To ensure proper operation, never change
the FSCO bit unless the EFCOP is in individual reset state (that is, FEN = 0).
7
FPRC
0
Filter Processing (FPRC) State Initialization Mode
This read/write control bit defines the EFCOP processing initialization mode. When
this bit is cleared, the EFCOP starts processing after a state initialization. (The
EFCOP machine starts computing once the FDM bank contains N input samples for
an N tap filter). When this bit is set, the EFCOP starts processing with no state
initialization. (The EFCOP machine starts computing as soon as the first data sample
is available in the input buffer.) To ensure proper operation, never change the FPRC
bit unless the EFCOP is in individual reset state (that is, FEN = 0).
6
FMLC
0
Filter Multichannel (FMLC) Mode
This read/write control bit enables multichannel mode, allowing the EFCOP to
process several filters (defined by FCHL[5:0] bits in FDCH register) concurrently by
sequentially entering a different sample to each filter. If FMLC is cleared, multichannel
mode is disabled, and the EFCOP operates in single filter mode. To ensure proper
operation, never change the FMLC bit unless the EFCOP is in individual reset state
(that is, FEN = 0).
DSP56321 Reference Manual, Rev. 1
11-38
Freescale Semiconductor
EFCOP Programming Model
Table 11-7. FCSR Bits (Continued)
Bit
Number
5–4
Bit Name
FOM[1–0
]
Reset
Value
0
Description
Filter Operation Mode
This pair of read/write control bits defines one of four operation modes if the FIR filter
is selected (that is, FLT is cleared):
•
•
•
•
FOM
FOM
FOM
FOM
= 00—Mode 0: Real FIR filter
= 01—Mode 1: Full complex FIR filter
= 10—Mode 2: Complex FIR filter with alternate real and imaginary outputs
= 11—Mode 3: Magnitude
To ensure proper operation, never change the FOM bits unless the EFCOP is in the
individual reset state (that is, FEN = 0).
3
FUPD
0
Filter Update
This read/write control/status bit enables the EFCOP to start a single coefficient
update session. Upon completion of the session, the FUPD bit is automatically
cleared. FUPD is automatically set when the EFCOP is in adaptive mode (that is,
FADP = 1).
2
FADP
0
Filter Adaptive (FADP) Mode
This read/write control bit enables adaptive mode. Adaptive mode is an efficient way
to implement a LMS-type filter, and therefore it is used when the EFCOP operates in
FIR filter mode (FLT = 0). In adaptive mode, processing of every input data sample
consists of FIR processing followed by a coefficient update. When FADP is set, the
EFCOP completes the FIR processing on the current data sample and immediately
starts the coefficient update assuming that a K-constant value is written to the FKIR. If
no value is written to the FKIR for the current data sample, the EFCOP halts
processing until the K-constant is written to the FKIR. During the coefficient update,
the FUPD bit is automatically set to indicate an update session. After completion of
the update, the EFCOP starts processing the next data sample.
1
FLT
0
Filter (FLT) Type
This read/write control bit selects one of two available filter types:
• FLT = 0—FIR filter
• FLT = 1—IIR filter
Note:
0
FEN
0
To ensure proper operation, never change the FLT bit unless the EFCOP is
in the individual reset state (that is, FEN = 0).
Filter Enable
This read/write control bit enables the operation of the EFCOP. When FEN is cleared,
operation is disabled and the EFCOP is in the individual reset state.
In the individual reset state, the EFCOP is inactive; internal logic and status bits
assume the same state as that produced by a hardware RESET signal or a software
RESET instruction; the contents of the FCNT, FDBA, and FCBA registers are
preserved; and the control bits in FCSR and FACR remain unchanged.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-39
Enhanced Filter Coprocessor
11.4.6 EFCOP ALU Control Register (FACR)
The FACR is a read/write register by which the DSP56300 core controls the main operation
modes of the EFCOP ALU.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
FISL
FSA
FSM
FRM1
FRM0
FSCL1
FSCL0
=
Reserved bit; read as 0; write with 0 for future compatibility
=
Reserved for internal use; read as 0; write with 0 for proper use.
Table 11-8. EFCOP ALU Control Register (FACR) Bits
Bit
Number
Bit Name
Reset
Value
Description
23–16
0
Reserved. They read as 0; write with 0 for future compatibility.
15–12
0
Reserved for internal use. Written as 0 for proper operation.
11–7
0
Reserved and unused. They read as 0; write with 0 for future compatibility.
6
FISL
0
Filter Input Scale
When set, this read/write control bit directs the EFCOP ALU to scale the IIR feedback
terms but not the IIR input. When cleared, the EFCOP ALU scales both the IIR feedback
terms and the IIR input. The scaling value in both cases is determined by the FSCL[1:0]
bits.
5
FSA
0
Filter Sixteen-bit Arithmetic (FSA) Mode
When set, this read/write control bit enables FSA mode. In this mode, the rounding of
the arithmetic operation is performed on Bit 31 of the 56-accumulator instead of the
usual bit 23 of the 56-bit accumulator. The scaling of the EFCOP data ALU is affected
accordingly.
4
FSM
0
Filter Saturation Mode
When set, this read/write control bit selects automatic saturation on 48 bits for the
results going to the accumulator. A special circuit inside the EFCOP MAC unit then
saturates those results. The purpose of this bit is to provide arithmetic saturation mode
for algorithms that do not recognize or cannot take advantage of the extension
accumulator.
3–2
FRM[1–0]
0
Filter Rounding Mode
These read/write control bits select the type of rounding performed by the EFCOP data
ALU during arithmetic operation:
• FRM = 00—Convergent rounding
• FRM = 01—Two’s complement rounding
• FRM = 10—Truncation (no rounding)
• FRM = 11—Reserved for future expansion
These bits affect operation of the EFCOP data ALU.
DSP56321 Reference Manual, Rev. 1
11-40
Freescale Semiconductor
EFCOP Programming Model
Table 11-8. EFCOP ALU Control Register (FACR) Bits (Continued)
Bit
Number
Bit Name
Reset
Value
1–0
FSCL[1–0]
0
Description
Filter Scaling (FSCL)
These read/write control bits select the scaling factor of the FMAC result:
• FSCL = 00—Scaling factor = 1 (no shift)
• FSCL = 01—Scaling factor = 8 (3-bit arithmetic left shift)
• FSCL = 10—Scaling factor = 16 (4-bit arithmetic left shift)
• FSCL = 11—Reserved for future expansion
To ensure proper operation, never change the FSCL bits unless the EFCOP is in the
individual reset state (that is, FEN = 0).
11.4.7 EFCOP Data Base Address (FDBA)
The FDBA is a 16-bit read/write counter register used as an address pointer to the EFCOP FDM
bank. FDBA points to the location to write the next data sample. The FDBA points to a modulo
delay buffer of size M, defined by the filter length (M = FCNT[11:0] + 1). The address range of
this modulo delay buffer is defined by lower and upper address boundaries. The lower address
–
boundary is the FDBA value with 0 in the k-LSBs, where 2k ≥ M ≥ 2k 1 ; it therefore must be a
multiple of 2k. The upper boundary is equal to the lower boundary plus (M – 1). Since M ≤ 2 k ,
once M has been chosen (that is, FCNT has been assigned), a sequential series of data memory
blocks (each of length 2k) will be created where multiple circular buffers for multichannel
filtering can be located. If M < 2 k , there will be a space between sequential circular buffers of
2 k – M . The address pointer is not required to start at the lower address boundary or to end on the
upper address boundary. It can point anywhere within the defined modulo address range. If the
data address pointer (FDBA) increments and reaches the upper boundary of the modulo buffer, it
will wrap around to the lower boundary.
11.4.8 EFCOP Coefficient Base Address (FCBA)
The FCBA is a 16-bit read/write counter register used as an address pointer to the EFCOP FCM
bank. FCBA points to the first location of the coefficient table. The FCBA points to a modulo
buffer of size M, defined by the filter length (M = FCNT[11:0] + 1). The address range of this
modulo buffer is defined by lower and upper address boundaries. The lower address boundary is
the FCBA value with 0 in the k-LSBs, where 2 k ≥ M ≥ 2 k – 1 ; it therefore must be a multiple of 2k.
The upper boundary is equal to the lower boundary plus (M – 1). Since M ≤ 2k , once M has been
chosen (that is, FCNT has been assigned), a sequential series of coefficient memory blocks (each
of length 2k) is created where multiple circular buffers for multichannel filtering can be located.
If M < 2 k , there will be a space between sequential circular buffers of 2 k – M . The FCBA address
pointer must be assigned to the lower address boundary (that is, it must have 0 in its k-LSBs). In
a compute session, the coefficient address pointer always starts at the lower boundary and ends at
the upper address boundary. Therefore, a FCBA read always gives the value of the lower address
boundary.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-41
Enhanced Filter Coprocessor
11.4.9 Decimation/Channel Count Register (FDCH)
The FDCH is a read/write register that sets the number of channels used in multichannel mode
(FCHL) and sets the decimation ratio in FIR filter mode. FDCH must be written before the FEN
enables the EFCOP. FDCH should be changed only when the EFCOP is in individual reset state
(FEN = 0); otherwise, improper operation may result. The number stored in FCHL is used by the
EFCOP address generation logic to generate the correct address for the FDM bank and for the
FCM bank in multichannel mode. When the EFCOP enable bit (FEN) is cleared, the EFCOP is in
individual reset state. In this state, the EFCOP is inactive, and the contents of FDCH register are
preserved.
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
FDCM3
FDCM2
FDCM1
FDCM0
FCHL5
FCHL4
FCHL3
FCHL2
FCHL1
FCHL0
=
Reserved bit; read as 0; write with 0 for future compatibility
Table 11-9. Decimation/Channel Count Register (FDCH) Bits
Bit
Number
Bit Name
23–12
11–8
FDCM[3–0]
7–6
5–0
FCHL[5–0]
Reset
Value
Description
0
These bits are reserved and unused. They read as 0; write with 0 for future
compatibility.
0
Filter Decimation
These read/write control bits select the decimation function. There are 16 decimation
factor options (from 1 to 16). To ensure proper operation, never change the FDCM bits
unless the EFCOP is in the individual reset state (FEN = 0).
0
Reserved and unused. They read as 0; write with 0 for future compatibility.
0
Filter Channels
These read/write control bits determine the number of filter channels to process
simultaneously (from 1 to 64) in multichannel mode. The number represented by the
FCHL bits is one less than the number of channels to be processed; that is, if FCHL =
0, then 1 channel is processed; if FCHL =1, then 2 channels are processed; and so on.
To ensure proper operation, never change the FCHL bits unless the EFCOP is in the
individual reset state (FEN = 0).
DSP56321 Reference Manual, Rev. 1
11-42
Freescale Semiconductor
EFCOP Programming Model
11.4.10 EFCOP Interrupt Vectors
Table 11-10 shows the EFCOP interrupt vectors, and Table 11-11 shows the DMA request
sources.
Table 11-10. EFCOP Interrupt Vectors
Interrupt
Address
Interrupt Vector
Priority
Interrupt
Enable
Interrupt
Conditions
VBA + $68
Data input buffer empty
Highest
FDIIE
FDIBE = 1
VBA + $6A
Data output buffer full
Lowest
FDOIE
FDOBF = 1
Table 11-11. EFCOP DMA Request Sources
Requesting Device Number
EFCOP input buffer empty
EFCOP output buffer full
Request Conditions
Peripheral Request
MDRQ
FDIBE = 1
FDOBF = 1
MDRQ11
MDRQ12
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
11-43
Enhanced Filter Coprocessor
DSP56321 Reference Manual, Rev. 1
11-44
Freescale Semiconductor
A
Bootstrap Program
; BOOTSTRAP CODE FOR DSP56321 - (C) Copyright 2000 Freescale Semiconductor, Inc.
; Revised March, 18 1997. And again Dec 1999
;
; Bootstrap through the Host Interface, External EPROM or SCI.
;
; This is the Bootstrap program contained in the DSP56321 192-word Boot
; ROM. This program can load any program RAM segment from an external
; EPROM, from the Host Interface or from the SCI serial interface.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; If MD:MC:MB:MA=x000,
then
the
; will start fetching instructions
; or 0x008000
; used.
(MD=1)
The accesses
assuming
will
Boot
ROM is bypassed
beginning
that
with address 0xC00000 (MD=0)
an external
be performed
and the DSP
using
memory
31 wait
of SRAM type is
states
with no
; address attributes selected (default area).
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Operation modes MD:MC:MB:MA=0001-0111 are reserved.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
If MD:MC:MB:MA=1001, then it loads a program RAM segment from consecutive
byte-wide P memory locations, starting at P:0xD00000 (bits 7-0).
The memory is selected by the Address Attribute AA1 and is accessed with
31 wait states.
The EPROM bootstrap code expects to read 3 bytes
specifying the number of program words, 3 bytes specifying the address
to start loading the program words and then 3 bytes for each program
word to be loaded. The number of words, the starting address and the
program words are read least significant byte first followed by the
mid and then by the most significant byte.
The program words will be condensed into 24-bit words and stored in
contiguous PRAM memory locations starting at the specified starting address.
After reading the program words, program execution starts from the same
address where loading started.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; If MD:MC:MB:MA=1010, then it loads the program RAM from the SCI interface.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-1
Bootstrap Program
; The number of program words to be loaded and the starting address must
; be specified. The SCI bootstrap code expects to receive 3 bytes
; specifying the number of program words, 3 bytes specifying the address
; to start loading the program words and then 3 bytes for each program
; word to be loaded. The number of words, the starting address and the
; program words are received least significant byte first followed by the
; mid and then by the most significant byte. After receiving the
; program words, program execution starts in the same address where
; loading started. The SCI is programmed to work in asynchronous mode
; with 8 data bits, 1 stop bit and no parity. The clock source is
; external and the clock frequency must be 16x the baud rate.
; After each byte is received, it is echoed back through the SCI
; transmitter.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Operation mode MD:MC:MB:MA=1011 is reserved.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; If MD:MC:MB:MA=1100, then it loads the program RAM from the Host
; Interface programmed to operate in the ISA mode.
; The HOST ISA bootstrap code expects to read a 24-bit word
; specifying the number of program words, a 24-bit word specifying the address
; to start loading the program words and then a 24-bit word for each program
; word to be loaded. The program words
will be stored in
; contiguous PRAM memory locations starting at the specified starting address.
; After reading the program words, program execution starts from the same
; address where loading started.
; The Host Interface bootstrap load program may be stopped by
; setting the Host Flag 0 (HF0). This will start execution of the loaded
; program from the specified starting address.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; If MD:MC:MB:MA=1101, then it loads the program RAM from the Host
; Interface programmed to operate in the HC11 non multiplexed mode.
;
DSP56321 Reference Manual, Rev. 1
A-2
Freescale Semiconductor
; The HOST HC11
bootstrap code expects to read a 24-bit word
; specifying the number of program words, a 24-bit word specifying the address
; to start loading the program words and then a 24-bit word for each program
; word to be loaded. The program words
will be stored in
; contiguous PRAM memory locations starting at the specified starting address.
; After reading the program words, program execution starts from the same
; address where loading started.
; The Host Interface bootstrap load program may be stopped by
; setting the Host Flag 0 (HF0). This will start execution of the loaded
; program from the specified starting address.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; If MD:MC:MB:MA=1110, then it loads the program RAM from the Host
; Interface programmed to operate in the 8051 multiplexed bus mode,
; in double-strob pin configuration.
; The HOST 8051 bootstrap code expects accesses that are byte wide.
; The HOST 8051 bootstrap code expects to read 3 bytes forming a 24-bit word
; specifying the number of program words, 3 bytes forming a 24-bit word
; specifying the address to start loading the program words and then 3 bytes
; forming 24-bit words for each program word to be loaded.
; The program words
will be stored in contiguous PRAM memory locations
; starting at the specified starting address.
; After reading the program words, program execution starts from the same
; address where loading started.
; The Host Interface bootstrap load program may be stopped by setting the
; Host Flag 0 (HF0). This will start execution of the loaded program from
; the specified starting address.
;
; The base address of the HI08 in multiplexed mode is 0x80 and is not
; modified by the bootstrap code. All the address lines are enabled
; and should be connected accordingly.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; If MD:MC:MB:MA=1111, then it loads the program RAM from the Host
; Interface programmed to operate in the MC68302 (IMP) bus mode,
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-3
Bootstrap Program
; in single-strob pin configuration.
; The HOST MC68302 bootstrap code expects accesses that are byte wide.
; The HOST MC68302 bootstrap code expects to read 3 bytes forming a 24-bit word
; specifying the number of program words, 3 bytes forming a 24-bit word
; specifying the address to start loading the program words and then 3 bytes
; forming 24-bit words for each program word to be loaded.
; The program words
will be stored in contiguous PRAM memory locations
; starting at the specified starting address.
; After reading the program words, program execution starts from the same
; address where loading started.
; The Host Interface bootstrap load program may be stopped by setting the
; Host Flag 0 (HF0). This will start execution of the loaded program from
; the specified starting address.
;
;;;;;;;;;;;;;;;;;;;; MEMORY EQUATES ;;;;;;;;;;;;;;;;;;;;;;;;
page
132,55,0,0,0
EQUALDATA
opt
mex
equ
1
;; 1 if xram and yram are of equal
;; size and addresses, 0 otherwise.
if
(EQUALDATA)
start_dram
end_dram
equ
equ
0
0x6000
;; 24k X and Y RAM
;; same addresses
else
start_xram
end_xram
equ
equ
start_yram
end_yram
equ
equ
0
;; 24k XRAM
0x6000
0
;; 24k YRAM
0x6000
endif
start_pram
end_pram
equ
equ
0
;; 16k PRAM
0x4000
DSP56321 Reference Manual, Rev. 1
A-4
Freescale Semiconductor
DATA_START
equ 0x1000
;; for dma, first 4k are shared memory
PSTART
equ 0
BLOCK
equ 0x400
ONE_BLOCK
equ (BLOCK-1) ;; for dma counter
PBLOCKS
equ (end_pram-PSTART)/BLOCK
DBLOCKS
equ (end_dram-DATA_START)/BLOCK
DMA_YP
equ 0x9882d9 ; de triggered
y+1->p+1
DMA_YX
equ 0x9882d1 ; de triggered
y+1->x+1
DMA_YY
equ 0x9882d5 ; de triggered
y+1->y+1
;; dma equates
M_DSR0
EQU
0xFFFFEF
; DMA0 Source Address Register
M_DDR0
EQU
0xFFFFEE
; DMA0 Destination Address Register
M_DCO0
EQU
0xFFFFED
; DMA0 Counter
M_DCR0
EQU
0xFFFFEC
; DMA0 Control Register
M_DTD0
EQU
0
; DMA Channel Transfer Done Status 0
M_DSTR
EQU
0xFFFFF4
; DMA Status Register
;;
;;;;;;;;;;;;;;;;;;;; GENERAL EQUATES ;;;;;;;;;;;;;;;;;;;;;;;;
;;
BOOT
equ
0xD00000
; this is the location in P memory
; on the external memory bus
; where the external byte-wide
; EPROM would be located
AARV
equ
0xD00409
; AAR1 selects the EPROM as CE~
; mapped as P from 0xD00000 to
; 0xDFFFFF, active low
;;
;;;;;;;;;;;;;;;;;;;; DSP I/O REGISTERS ;;;;;;;;;;;;;;;;;;;;;;;;
;;
M_PDRC
EQU
0xFFFFBD
;; Port C GPIO Data Register
M_PRRC
EQU
0xFFFFBE
;; Port C Direction Register
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-5
Bootstrap Program
M_SSR
EQU
0xFFFF93
; SCI Status Register
M_STXL
EQU
0xFFFF95
; SCI Transmit Data Register (low)
M_SRXL
EQU
0xFFFF98
; SCI Receive Data Register (low)
M_SCCR
EQU
0xFFFF9B
; SCI Clock Control Register
M_SCR
EQU
0xFFFF9C
; SCI Control Register
M_PCRE
EQU
0xFFFF9F
; Port E Control register
M_AAR1
EQU
0xFFFFF8
; Address Attribute Register 1
M_HPCR
EQU
0xFFFFC4
; Host Polarity Control Register
M_HSR
EQU
0xFFFFC3
; Host Status Rgister
M_HRX
EQU
0xFFFFC6
; Host Recceive Register
HRDF
EQU
0x0
; Host Receive Data Full
HF0
EQU
0x3
; Host Flag 0
HEN
EQU
0x6
; Host Enable
SCK0
EQU
0x3
;; SCK0 is bit #3 as GPIO
ORG PL:0xff0000,PL:0xff0000
; bootstrap code starts at 0xff0000
START
clr a
movec
; clear a
omr,a1
and #0xf,a
TABLE
move
a1,n0
move
#TABLE,r0
;; Table is here because it should actuallly start from 0
jmp
(r0)+n0
bra
<EPROMLD
; MD:MC:MB:MA=0001 , load from eprom
bra
<SCILD
; MD:MC:MB:MA=0010 , load from SCI
bra
<SCILD
; MD:MC:MB:MA=0011 , load from SCI
bra
<ISAHOSTLD
; If MD:MC:MB:MA=0100, load from ISA HOST
bra
<HC11HOSTLD
; If MD:MC:MB:MA=0101, load from HC11 Host
one
two
three
four
five
DSP56321 Reference Manual, Rev. 1
A-6
Freescale Semiconductor
six
bra
<I8051HOSTLD
; If MD:MC:MB:MA=0110, load from 8051 Host
bra
<BURN
; If MD:MC:MB:MA=0111, burn in
bra
<EPROMLD
; MD:MC:MB:MA=1001 , load from eprom
bra
<SCILD
; MD:MC:MB:MA=1010 , load from SCI
bra
<SCILD
; MD:MC:MB:MA=1011 ,reserved, SCI for now
bra
<ISAHOSTLD
; If MD:MC:MB:MA=1100, load from ISA HOST
<HC11HOSTLD
; If MD:MC:MB:MA=1101, load from HC11 Host
bra
<I8051HOSTLD
; If MD:MC:MB:MA=1110, load from 8051 Host
bra
<MC68302HOSTLD
; If MD:MC:MB:MA=1111, load from MC68302 Host
seven
eight
nop
nine
ten
eleven
twelve
thirteen
bra
fourteen
fifteen
;========================================================================
; This is the routine which loads a program through the HI08 host port
; The program is downloaded from the host MCU with the following rules:
; 1) 3 bytes - Define the program length.
; 2) 3 bytes - Define the address to which to start loading the program to.
; 3) 3n bytes (while n is any integer number)
; The program words will be stroed in contiguous PRAM memory locations starting
; at the specified starting address.
; After reading the program words, program execution starts from the same
; address where loading started.
; The host MCU may terminate the loading process by setting the HF1=0 and HF0=1.
; When the downloading is terminated, the program will start execution of the
; loaded program from the specified starting address.
; The HI08 boot ROM program enables the following busses to download programs
; through the HI08 port:
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-7
Bootstrap Program
;
1 - ISA
;
;
pulses duale positive request
2 - HC11
;
;
- Single strobe non-multiplexed bus with positive strobe
pulse single negative request.
4 - i8051
;
;
- Dual strobes non-multiplexed bus with negative strobe
- Dual strobes multiplexed bus with negative strobe pulses
dual negative request.
5 - MC68302
;
- Single strobe non-multiplexed bus with negative strobe
pulse single negative request.
;========================================================================
MC68302HOSTLD
movep
#%0000000000111000,x:M_HPCR
; Configure the following conditions:
; HAP
= 0 Negative host acknowledge
; HRP
= 0 Negative host request
; HCSP
= 0 Negatice chip select input
; HD/HS = 0 Single strobe bus (R/W~ and DS)
; HMUX
= 0 Non multiplexed bus
; HASP
= 0 (address strobe polarity has no
;
meaning in non-multiplexed bus)
; HDSP
= 0 Negative data stobes polarity
; HROD
= 0 Host request is active when enabled
; spare = 0 This bit should be set to 0 for
;
; HEN
;
future compatability
= 0 When the HPCR register is modified
HEN should be cleared
; HAEN
= 1 Host acknowledge is enabled
; HREN
= 1 Host requests are enabled
; HCSEN = 1 Host chip select input enabled
; HA9EN = 0 (address 9 enable bit has no
;
meaning in non-multiplexed bus)
; HA8EN = 0 (address 8 enable bit has no
;
; HGEN
bra
meaning in non-multiplexed bus)
= 0 Host GPIO pins are disabled
<HI08CONT
DSP56321 Reference Manual, Rev. 1
A-8
Freescale Semiconductor
ISAHOSTLD
movep
#%0101000000011000,x:M_HPCR
; Configure the following conditions:
; HAP
= 0 Negative host acknowledge
; HRP
= 1 Positive host request
; HCSP
= 0 Negatice chip select input
; HD/HS = 1 Dual strobes bus (RD and WR)
; HMUX
= 0 Non multiplexed bus
; HASP
= 0 (address strobe polarity has no
;
meaning in non-multiplexed bus)
; HDSP
= 0 Negative data stobes polarity
; HROD
= 0 Host request is active when enabled
; spare = 0 This bit should be set to 0 for
;
; HEN
future compatability
= 0 When the HPCR register is modified
;
HEN should be cleared
; HAEN
= 0 Host acknowledge is disabled
; HREN
= 1 Host requests are enabled
; HCSEN = 1 Host chip select input enabled
; HA9EN = 0 (address 9 enable bit has no
;
meaning in non-multiplexed bus)
; HA8EN = 0 (address 8 enable bit has no
;
; HGEN
bra
meaning non-multiplexed bus)
= 0 Host GPIO pins are disabled
<HI08CONT
HC11HOSTLD
movep
#%0000001000011000,x:M_HPCR
; Configure the following conditions:
; HAP
= 0 Negative host acknowledge
; HRP
= 0 Negative host request
; HCSP
= 0 Negatice chip select input
; HD/HS = 0 Single strobe bus (R/W~ and DS)
; HMUX
= 0 Non multiplexed bus
; HASP
= 0 (address strobe polarity has no
;
meaning in non-multiplexed bus)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-9
Bootstrap Program
; HDSP
= 1 Negative data stobes polarity
; HROD
= 0 Host request is active when enabled
; spare = 0 This bit should be set to 0 for
;
; HEN
future compatability
= 0 When the HPCR register is modified
;
HEN should be cleared
; HAEN
= 0 Host acknowledge is disabled
; HREN
= 1 Host requests are enabled
; HCSEN = 1 Host chip select input enabled
; HA9EN = 0 (address 9 enable bit has no
;
meaning in non-multiplexed bus)
; HA8EN = 0 (address 8 enable bit has no
;
; HGEN
bra
meaning in non-multiplexed bus)
= 0 Host GPIO pins are disabled
<HI08CONT
I8051HOSTLD
movep
#%0001110000011110,x:M_HPCR
; Configure the following conditions:
; HAP
= 0 Negative host acknowledge
; HRP
= 0 Negatice host request
; HCSP
= 0 Negatice chip select input
; HD/HS = 1 Dual strobes bus (RD and WR)
; HMUX
= 1 Multiplexed bus
; HASP
= 1 Positive address strobe polarity
; HDSP
= 0 Negative data stobes polarity
; HROD
= 0 Host request is active when enabled
; spare = 0 This bit should be set to 0 for
;
; HEN
;
future compatability
= 0 When the HPCR register is modified
HEN should be cleared
; HAEN
= 0 Host acknowledge is disabled
; HREN
= 1 Host requests are enabled
; HCSEN = 1 Host chip select input enabled
; HA9EN = 1 Enable address 9 input
; HA8EN = 1 Enable address 8 input
DSP56321 Reference Manual, Rev. 1
A-10
Freescale Semiconductor
; HGEN
= 0 Host GPIO pins are disabled
HI08CONT
bset
#HEN,x:M_HPCR
; Enable the HI08 to operate as host
; interface (set HEN=1)
jclr
#HRDF,x:M_HSR,*
; wait for the program length to be
; written
movep
x:M_HRX,a0
jclr
#HRDF,x:M_HSR,*
; wait for the program starting address
; to be written
movep
x:M_HRX,r0
move
r0,r1
do
a0,HI08LOOP
; set a loop with the downloaded length
jset
#HRDF,x:M_HSR,HI08NW
; If new word was loaded then jump to
HI08LL
; read that word
jclr
#HF0,x:M_HSR,HI08LL
; If HF0=0 then continue with the
; downloading
enddo
; Must terminate the do loop
bra
<HI08LOOP
movep
x:M_HRX,p:(r0)+
HI08NW
; Move the new word into its destination
; location in the program RAM
nop
; pipeline delay
HI08LOOP
bra
<FINISH
;========================================================================
; This is the routine that loads from the SCI.
; MD:MC:MB:MA=1010 - external SCI clock
SCILD
movep #0x0302,X:M_SCR
; Configure SCI Control Reg
; mode 2 (10 bit async)
; LSB first, wakeup disabled,
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-11
Bootstrap Program
; no wired OR, receiver enable,
; trasmit enable, clk divide by 32,
; positive clk, no recieve interrupt
movep #0xC000,X:M_SCCR
; Configure SCI Clock Control Reg
; external tx clock, external rx clock,
; prescaler divide by1, 1x clock
; clock divide ratio = 1
movep #7,X:M_PCRE
; Configure SCLK, TXD and RXD
; as SCI pins
do #6,_LOOP6
; get 3 bytes for number of
; program words and 3 bytes
; for the starting address
jclr #2,X:M_SSR,*
; Wait for RDRF to go high
movep X:M_SRXL,A2
; Put 8 bits in A2
jclr #1,X:M_SSR,*
; Wait for TDRE to go high
movep A2,X:M_STXL
; echo the received byte
asr #8,a,a
_LOOP6
move a1,r0
; starting address for load
move a1,r1
; save starting address
do a0,_LOOP7
; Receive program words
do #3,_LOOP8
jclr #2,X:M_SSR,*
; Wait for RDRF to go high
movep X:M_SRXL,A2
; Put 8 bits in A2
jclr #1,X:M_SSR,*
; Wait for TDRE to go high
movep a2,X:M_STXL
; echo the received byte
asr #8,a,a
_LOOP8
movem a1,p:(r0)+
; Store 24-bit result in P mem.
nop
; pipeline delay
bra <FINISH
; Boot from SCI done
_LOOP7
DSP56321 Reference Manual, Rev. 1
A-12
Freescale Semiconductor
;========================================================================
; This is the routine that loads from external EPROM.
; MD:MC:MB:MA=1001
EPROMLD
move #BOOT,r2
; r2 = address of external EPROM
movep #AARV,X:M_AAR1
; aar1 configured for SRAM types of access
do #6,_LOOP9
; read number of words and starting address
movem p:(r2)+,a2
; Get the 8 LSB from ext. P mem.
asr #8,a,a
; Shift 8 bit data into A1
_LOOP9
;
move a1,r0
; starting address for load
move a1,r1
; save it in r1
; a0 holds the number of words
do a0,_LOOP10
; read program words
do #3,_LOOP11
; Each instruction has 3 bytes
movem p:(r2)+,a2
; Get the 8 LSB from ext. P mem.
asr #8,a,a
; Shift 8 bit data into A1
_LOOP11
; Go get another byte.
movem a1,p:(r0)+
; Store 24-bit result in P mem.
nop
; pipeline delay
_LOOP10
; and go get another 24-bit word.
; Boot from EPROM done
;========================================================================
FINISH
; This is the exit handler that returns execution to normal
; expanded mode and jumps to the RESET vector.
andi #0x0,ccr
jmp (r1)
; Clear CCR as if RESET to 0.
; Then go to starting Prog addr.
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-13
Bootstrap Program
;========================================================================
; The following modes are reserved, some of which are used for internal testing
; Can be implemented in future.
;
;========================================================================
; This mode is reserved for internal testing purposes
; MD:MC:MB:MA=0111
;;--------------------------------------------------------;;
;;
burnin mode
;;
;;
Intended to be used for burn-in test. Wake up from reset
;;
with PINIT set for execution in maximum frequency.
;;
All RAM locations are validated, arithmetic/logic operations
;;
are validated (add, eor) and exercised (mac).
;;
While all tests pass, the SCK0 pin will continue to toggle.
;;
When the test fails the DSP enters DEBUG and stops execution.
;;
;;--------------------------------------------------------BURN
;;
prepare patterns
clr b
move
#0xaaaaaa,x0
move
#0x555555,x1
move
#0xcccccc,y0
;; configure SCK0 as gpio output. PRRC register is cleared at reset.
movep
b,x:M_PDRC
;; clear GPIO data register
bset
#SCK0,x:M_PRRC
;; Define SCK0 as GPIO output
;; SCK0 toggles means test pass
dor #9,burn1
;;---------------------------;; test RAM
;;---------------------------;; write pattern to all memory locations
DSP56321 Reference Manual, Rev. 1
A-14
Freescale Semiconductor
;; assume EQUALDATA
;; write x and y memory
clr a
#start_dram,r0
move
#>end_dram,n0
rep
n0
mac x0,x1,a x,l:(r0)+
;; start of x/y ram
;; length of x/y ram
;; exercise mac, write x/y ram
;; write p memory
clr a
#>start_pram,r2
move
#>end_pram,n2
rep
n2
move
y0,p:(r2)+
;; start of pram
;; length of pram
;; write pram
;; check memory contents
;; assume EQUALDATA
;; check dram
clr a
#start_dram,r0
;; restore pointer, clear a
do
n0,_loopd
move
x:(r0),a1
eor
x1,a
add
a,b
;; accumulate error in b
move
y:(r0)+,a1
;; a0=a2=0
eor
x0,a
add
a,b
;; a0=a2=0
;; accumulate error in b
_loopd
;; check pram
clr a
#start_pram,r2
do
n2,_loopp
move
p:(r2)+,a1
eor
y0,a
add
a,b
;; restore pointer, clear a
;; a0=a2=0
;; accumulate error in b
_loopp
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-15
Bootstrap Program
;;--------------------------------------------------;; toggle pin if no errors, stop execution otherwise.
;;--------------------------------------------------beq
label1
bclr
#SCK0,x:M_PDRC
enddo
bra
;; clear sck0 if error,
;; terminate the loop normally
<burn1
;; and stop execution
label1
;; if no error
bchg
#SCK0,x:M_PDRC
;; toggle pin and keep on looping
;; exercise dma during burn-in
move #DATA_START,n0
clr
a #>0x010101,x1
;; fill one block in Y memory as source
move
n0,r0
rep
#BLOCK
add
x1,a
a1,y:(r0)+
;; exercise Pram dma data path, no checking of results
move n0,r0
move #PSTART,r1
move #DMA_YP,r2
move #PBLOCKS,r3
bsr <do_mem_dma
;; exercise Xram dma data path, no checking of results
move n0,r0
move #DATA_START,r1
move #DMA_YX,r2
move #DBLOCKS,r3
bsr <do_mem_dma
;; exercise Yram dma data path, no checking of results
move n0,r0
;; no change in r1 or r3
;;
move #PSTART,r1
;;
move #DBLOCKS,r3
move #DMA_YY,r2
bsr <do_mem_dma
DSP56321 Reference Manual, Rev. 1
A-16
Freescale Semiconductor
nop
nop
burn1
wait
;; enter wait after test completion
; subroutine to copy source from
DATA_START
;; to dest mem at r1
;; r2 has value for dma control reg
;; r3 has number of iterations (size/block)
do_mem_dma
movep
r1,x:M_DDR0
; memory initial address
dor r3,loopoo
movep
n0,x:M_DSR0
movep
#>ONE_BLOCK,x:M_DCO0
movep r2,x:M_DCR0
; BLOCK transfers.
; y->p,y->x or y->y
;; time required for transfer is 2*BLOCK+overhead
;; overhead=~ 10 cycles
nop
;; last dma xfer
rep #(2*BLOCK+10)
nop
loopoo
nop
rts ;; do_mem_dma
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
A-17
Bootstrap Program
DSP56321 Reference Manual, Rev. 1
A-18
Freescale Semiconductor
Programming Reference
B
This reference for programmers includes a table showing the addresses of all DSP
memory-mapped peripherals, an exception priority table, and programming sheets for the major
programmable DSP registers. The programming sheets are grouped in the following order:
Central Processor, Clock Generator (CLKGEN), Host Interface (HI08), Enhanced Synchronous
Serial Interface (ESSI), Serial Communication Interface (SCI), Timer, GPIO, and EFCOP. Each
sheet provides room to write in the value of each bit and the hexadecimal value for each register.
You can photocopy these sheets and reuse them for each application development project. For
details on the instruction set of the DSP56300 family of DSPs, see the DSP56300 Family
Manual.
„
„
„
„
Table B-2, Internal I/O Memory Map (X Data Memory), on page B-2 and Table B-3,
Internal I/O Memory Map (Y Data Memory), on page B-7 list the memory addresses of all
on-chip peripherals.
Table B-4, Interrupt Sources, on page B-7 lists the interrupt starting addresses and
sources.
Table B-5, Interrupt Source Priorities Within an IPL, on page B-9 lists the priorities of
specific interrupts within interrupt priority levels.
The programming sheets appear in this manual as figures (listed in Table B-1); they show
the major programmable registers on the DSP56321.
Table B-1. Guide to Programming Sheets
Module
Central
Processor
IPR
CLKGEN
BIU
DMA
Programming Sheet
Page
Figure B-1, Status Register (SR)
page B-11
Figure B-2, Digital Phase-Lock Loop Control (PCTL) Register
page B-13
Figure B-3, DPLL Static Control Register (DSCR)
page B-14
Figure B-4, DMA Control Registers 5–0 (DCR[5–0])
page B-17
Figure B-2, Digital Phase-Lock Loop Control (PCTL) Register
page B-13
Figure B-3, DPLL Static Control Register (DSCR)
page B-14
Figure B-7, Host Control Register
page B-20
Figure B-8, Interrupt Control and Command Vector Registers
page B-21
Figure B-4, DMA Control Registers 5–0 (DCR[5–0])
page B-17
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-1
Programming Reference
Table B-1. Guide to Programming Sheets (Continued)
HI08
ESSI
SCI
Timers
GPIO
EFCOP
Figure B-5, Host Transmit Data Register
page B-18
Figure B-6, Host Base Address and Host Port Control Registers
page B-19
Figure B-7, Host Control Register
page B-20
Figure B-8, Interrupt Control and Command Vector Registers
page B-21
Figure B-9, Interrupt Vector and Host Transmit Data Registers
page B-22
Figure B-10, ESSI Control Register A (CRA)
page B-23
Figure B-11, ESSI Control Register B (CRB)
page B-24
Figure B-12, ESSI Transmit and Receive Slot Mask Registers (TSM, RSM)
page B-25
Figure B-13, SCI Control Register (SCR)
page B-26
Figure B-14, SCI Clock Control Registers (SCCR)
page B-27
Figure B-15, Timer Prescaler Load Register (TPLR)
page B-28
Figure B-16, Timer Control/Status Register (TCSR)
page B-29
Figure B-22, Timer Load, Compare, and Count Registers (TLR, TCPR, TCR)
page B-30
Figure B-17, Host Data Direction and Host Data Registers (HDDR, HDR)
page B-31
Figure B-18, Port C Registers (PCRC, PRRC, PDRC)
page B-32
Figure B-19, Port D Registers (PCRD, PRRD, PDRD)
page B-33
Figure B-20, Port E Registers (PCRE, PRRE, PDRE)
page B-34
Figure B-21, EFCOP Counter and Control Status Registers (FCNT and FCSR)
page B-35
Figure B-22, EFCOP FACR, FDBA, FCBA, and FDCH Registers
page B-36
B.1 Internal I/O Memory Map
Table B-2. Internal I/O Memory Map (X Data Memory)
Peripheral
16-Bit Address
24-Bit Address
Register Name
IPR
$FFFF
$FFFFFF
Interrupt Priority Register Core (IPR-C)
$FFFE
$FFFFFE
Interrupt Priority Register Peripheral (IPR-P)
$FFFD
$FFFFFD
Reserved
OnCE
$FFFC
$FFFFFC
OnCE GDB Register (OGDB)
BIU
$FFFB
$FFFFFB
Bus Control Register (BCR)
$FFFA
$FFFFFA
Reserved
$FFF9
$FFFFF9
Address Attribute Register 0 (AAR0)
$FFF8
$FFFFF8
Address Attribute Register 1 (AAR1)
$FFF7
$FFFFF7
Address Attribute Register 2 (AAR2)
$FFF6
$FFFFF6
Address Attribute Register 3 (AAR3)
$FFF5
$FFFFF5
ID Register (IDR)
DSP56321 Reference Manual, Rev. 1
B-2
Freescale Semiconductor
Internal I/O Memory Map
Table B-2. Internal I/O Memory Map (X Data Memory) (Continued)
Peripheral
16-Bit Address
24-Bit Address
DMA
$FFF4
$FFFFF4
DMA Status Register (DSTR)
$FFF3
$FFFFF3
DMA Offset Register 0 (DOR0)
$FFF2
$FFFFF2
DMA Offset Register 1 (DOR1)
$FFF1
$FFFFF1
DMA Offset Register 2 (DOR2)
$FFF0
$FFFFF0
DMA Offset Register 3 (DOR3)
$FFEF
$FFFFEF
DMA Source Address Register (DSR0)
$FFEE
$FFFFEE
DMA Destination Address Register (DDR0)
$FFED
$FFFFED
DMA Counter (DCO0)
$FFEC
$FFFFEC
DMA Control Register (DCR0)
$FFEB
$FFFFEB
DMA Source Address Register (DSR1)
$FFEA
$FFFFEA
DMA Destination Address Register (DDR1)
$FFE9
$FFFFE9
DMA Counter (DCO1)
$FFE8
$FFFFE8
DMA Control Register (DCR1)
$FFE7
$FFFFE7
DMA Source Address Register (DSR2)
$FFE6
$FFFFE6
DMA Destination Address Register (DDR2)
$FFE5
$FFFFE5
DMA Counter (DCO2)
$FFE4
$FFFFE4
DMA Control Register (DCR2)
$FFE3
$FFFFE3
DMA Source Address Register (DSR3)
$FFE2
$FFFFE2
DMA Destination Address Register (DDR3)
$FFE1
$FFFFE1
DMA Counter (DCO3)
$FFE0
$FFFFE0
DMA Control Register (DCR3)
$FFDF
$FFFFDF
DMA Source Address Register (DSR4)
$FFDE
$FFFFDE
DMA Destination Address Register (DDR4)
$FFDD
$FFFFDD
DMA Counter (DCO4)
$FFDC
$FFFFDC
DMA Control Register (DCR4)
$FFDB
$FFFFDB
DMA Source Address Register (DSR5)
$FFDA
$FFFFDA
DMA Destination Address Register (DDR5)
$FFD9
$FFFFD9
DMA Counter (DCO5)
$FFD8
$FFFFD8
DMA Control Register (DCR5)
DMA0
DMA1
DMA2
DMA3
DMA4
DMA5
Register Name
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-3
Programming Reference
Table B-2. Internal I/O Memory Map (X Data Memory) (Continued)
Peripheral
CLKGEN/DPLL
Port B
HI08
Port C
16-Bit Address
24-Bit Address
Register Name
$FFD7
$FFFFD7
Reserved
$FFD6
$FFFFD6
Reserved
$FFD5
$FFFFD5
Reserved
$FFD4
$FFFFD4
Reserved
$FFD3
$FFFFD3
Reserved
$FFD2
$FFFFD2
Reserved
$FFD1
$FFFFD1
DPLL Control (PCTL) Register
$FFD0
$FFFFD0
DPLL Static Control Register (DSCR)
$FFCF
$FFFFCF
Reserved
$FFCE
$FFFFCE
Reserved
$FFCD
$FFFFCD
Reserved
$FFCC
$FFFFCC
Reserved
$FFCB
$FFFFCB
Reserved
$FFCA
$FFFFCA
Reserved
$FFC9
$FFFFC9
Host Port GPIO Data Register (HDR)
$FFC8
$FFFFC8
Host Port GPIO Direction Register (HDDR)
$FFC7
$FFFFC7
Host Transmit Register (HTX)
$FFC6
$FFFFC6
Host Receive Register (HRX)
$FFC5
$FFFFC5
Host Base Address Register (HBAR)
$FFC4
$FFFFC4
Host Port Control Register (HPCR)
$FFC3
$FFFFC3
Host Status Register (HSR)
$FFC2
$FFFFC2
Host Control Register (HCR)
$FFC1
$FFFFC1
Reserved
$FFC0
$FFFFC0
Reserved
$FFBF
$FFFFBF
Port C Control Register (PCRC)
$FFBE
$FFFFBE
Port C Direction Register (PRRC)
$FFBD
$FFFFBD
Port C GPIO Data Register (PDRC)
DSP56321 Reference Manual, Rev. 1
B-4
Freescale Semiconductor
Internal I/O Memory Map
Table B-2. Internal I/O Memory Map (X Data Memory) (Continued)
Peripheral
16-Bit Address
24-Bit Address
ESSI 0
$FFBC
$FFFFBC
ESSI 0 Transmit Data Register 0 (TX00)
$FFBB
$FFFFBB
ESSI 0 Transmit Data Register 1 (TX01)
$FFBA
$FFFFBA
ESSI 0 Transmit Data Register 2 (TX02)
$FFB9
$FFFFB9
ESSI 0 Time Slot Register (TSR0)
$FFB8
$FFFFB8
ESSI 0 Receive Data Register (RX0)
$FFB7
$FFFFB7
ESSI 0 Status Register (SSISR0)
$FFB6
$FFFFB6
ESSI 0 Control Register B (CRB0)
$FFB5
$FFFFB5
ESSI 0 Control Register A (CRA0)
$FFB4
$FFFFB4
ESSI 0 Transmit Slot Mask Register A (TSMA0)
$FFB3
$FFFFB3
ESSI 0 Transmit Slot Mask Register B (TSMB0)
$FFB2
$FFFFB2
ESSI 0 Receive Slot Mask Register A (RSMA0)
$FFB1
$FFFFB1
ESSI 0 Receive Slot Mask Register B (RSMB0)
$FFB0
$FFFFB0
Reserved
$FFAF
$FFFFAF
Port D Control Register (PCRD)
$FFAE
$FFFFAE
Port D Direction Register (PRRD)
$FFAD
$FFFFAD
Port D GPIO Data Register (PDRD)
$FFAC
$FFFFAC
ESSI 1 Transmit Data Register 0 (TX10)
$FFAB
$FFFFAB
ESSI 1 Transmit Data Register 1 (TX11)
$FFAA
$FFFFAA
ESSI 1 Transmit Data Register 2 (TX12)
$FFA9
$FFFFA9
ESSI 1 Time Slot Register (TSR1)
$FFA8
$FFFFA8
ESSI 1 Receive Data Register (RX1)
$FFA7
$FFFFA7
ESSI 1 Status Register (SSISR1)
$FFA6
$FFFFA6
ESSI 1 Control Register B (CRB1)
$FFA5
$FFFFA5
ESSI 1 Control Register A (CRA1)
$FFA4
$FFFFA4
ESSI 1 Transmit Slot Mask Register A (TSMA1)
$FFA3
$FFFFA3
ESSI 1 Transmit Slot Mask Register B (TSMB1)
$FFA2
$FFFFA2
ESSI 1 Receive Slot Mask Register A (RSMA1)
$FFA1
$FFFFA1
ESSI 1 Receive Slot Mask Register B (RSMB1)
$FFA0
$FFFFA0
Reserved
$FF9F
$FFFF9F
Port E Control Register (PCRE)
$FF9E
$FFFF9E
Port E Direction Register (PRRE)
$FF9D
$FFFF9D
Port E GPIO Data Register (PDRE)
Port D
ESSI 1
Port E
Register Name
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-5
Programming Reference
Table B-2. Internal I/O Memory Map (X Data Memory) (Continued)
Peripheral
16-Bit Address
24-Bit Address
SCI
$FF9C
$FFFF9C
SCI Control Register (SCR)
$FF9B
$FFFF9B
SCI Clock Control Register (SCCR)
$FF9A
$FFFF9A
SCI Receive Data Register—High (SRXH)
$FF99
$FFFF99
SCI Receive Data Register—Middle (SRXM)
$FF98
$FFFF98
SCI Receive Data Register—Low (SRXL)
$FF97
$FFFF97
SCI Transmit Data Register—High (STXH)
$FF96
$FFFF96
SCI Transmit Data Register—Middle (STXM)
$FF95
$FFFF95
SCI Transmit Data Register—Low (STXL)
$FF94
$FFFF94
SCI Transmit Address Register (STXA)
$FF93
$FFFF93
SCI Status Register (SSR)
$FF92
$FFFF92
Reserved
$FF91
$FFFF91
Reserved
$FF90
$FFFF90
Reserved
$FF8F
$FFFF8F
Timer 0 Control/Status Register (TCSR0)
$FF8E
$FFFF8E
Timer 0 Load Register (TLR0)
$FF8D
$FFFF8D
Timer 0 Compare Register (TCPR0)
$FF8C
$FFFF8C
Timer 0 Count Register (TCR0)
$FF8B
$FFFF8B
Timer 1 Control/Status Register (TCSR1)
$FF8A
$FFFF8A
Timer 1 Load Register (TLR1)
$FF89
$FFFF89
Timer 1 Compare Register (TCPR1)
$FF88
$FFFF88
Timer 1 Count Register (TCR1)
$FF87
$FFFF87
Timer 2 Control/Status Register (TCSR2)
$FF86
$FFFF86
Timer 2 Load Register (TLR2)
$FF85
$FFFF85
Timer 2 Compare Register (TCPR2)
$FF84
$FFFF84
Timer 2 Count Register (TCR2)
$FF83
$FFFF83
Timer Prescaler Load Register (TPLR)
$FF82
$FFFF82
Timer Prescaler Count Register (TPCR)
$FF81
$FFFF81
Reserved
$FF80
$FFFF80
Reserved
Triple Timer
Register Name
DSP56321 Reference Manual, Rev. 1
B-6
Freescale Semiconductor
Interrupt Sources and Priorities
Table B-3. Internal I/O Memory Map (Y Data Memory)
16-Bit
Address
Peripheral
Enhanced Filter
Coprocessor
(EFCOP)
24-Bit Address
Register Name
$FFBF
$FFFFBF
Reserved
$FFBE
$FFFFBE
Reserved
$FFBD
$FFFFBD
Reserved
$FFBC
$FFFFBC
Reserved
$FFBB
$FFFFBB
Reserved
$FFBA
$FFFFBA
Reserved
$FFB9
$FFFFB9
Reserved
$FFB8
$FFFFB8
EFCOP Decimation/Channel (FDCH) Register
$FFB7
$FFFFB7
EFCOP Coefficient Base Address (FCBA)
$FFB6
$FFFFB6
EFCOP Data Base Address (FDBA)
$FFB5
$FFFFB5
EFCOP ALU Control Register (FACR)
$FFB4
$FFFFB4
EFCOP Control Status Register (FCSR)
$FFB3
$FFFFB3
EFCOP Filter Count (FCNT) Register
$FFB2
$FFFFB2
EFCOP K-Constant Register (FKIR)
$FFB1
$FFFFB1
EFCOP Data Output Register (FDOR)
$FFB0
$FFFFB0
EFCOP Data Input Register (FDIR)
$FFAF–
$FF80
$FFFFAF–
$FFFF80
Reserved
B.2 Interrupt Sources and Priorities
Table B-4. Interrupt Sources
Interrupt
Starting Address
Interrupt
Priority Level
Range
VBA:$00
3
Hardware RESET
VBA:$02
3
Stack Error
VBA:$04
3
Illegal Instruction
VBA:$06
3
Debug Request Interrupt
VBA:$08
3
Trap
VBA:$0A
3
Non-Maskable Interrupt (NMI)
VBA:$0C
3
Reserved
Interrupt Source
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-7
Programming Reference
Table B-4. Interrupt Sources (Continued)
Interrupt
Starting Address
Interrupt
Priority Level
Range
VBA:$0E
3
VBA:$10
0–2
IRQA
VBA:$12
0–2
IRQB
VBA:$14
0–2
IRQC
VBA:$16
0–2
IRQD
VBA:$18
0–2
DMA Channel 0
VBA:$1A
0–2
DMA Channel 1
VBA:$1C
0–2
DMA Channel 2
VBA:$1E
0–2
DMA Channel 3
VBA:$20
0–2
DMA Channel 4
VBA:$22
0–2
DMA Channel 5
VBA:$24
0–2
Timer 0 Compare
VBA:$26
0–2
Timer 0 Overflow
VBA:$28
0–2
Timer 1 Compare
VBA:$2A
0–2
Timer 1 Overflow
VBA:$2C
0–2
Timer 2 Compare
VBA:$2E
0–2
Timer 2 Overflow
VBA:$30
0–2
ESSI0 Receive Data
VBA:$32
0–2
ESSI0 Receive Data With Exception Status
VBA:$34
0–2
ESSI0 Receive Last Slot
VBA:$36
0–2
ESSI0 Transmit Data
VBA:$38
0–2
ESSI0 Transmit Data With Exception Status
VBA:$3A
0–2
ESSI0 Transmit Last Slot
VBA:$3C
0–2
Reserved
VBA:$3E
0–2
Reserved
VBA:$40
0–2
ESSI1 Receive Data
VBA:$42
0–2
ESSI1 Receive Data With Exception Status
VBA:$44
0–2
ESSI1 Receive Last Slot
VBA:$46
0–2
ESSI1 Transmit Data
VBA:$48
0–2
ESSI1 Transmit Data With Exception Status
VBA:$4A
0–2
ESSI1 Transmit Last Slot
VBA:$4C
0–2
Reserved
VBA:$4E
0–2
Reserved
VBA:$50
0–2
SCI Receive Data
VBA:$52
0–2
SCI Receive Data With Exception Status
VBA:$54
0–2
SCI Transmit Data
Interrupt Source
Reserved
DSP56321 Reference Manual, Rev. 1
B-8
Freescale Semiconductor
Interrupt Sources and Priorities
Table B-4. Interrupt Sources (Continued)
Interrupt
Starting Address
Interrupt
Priority Level
Range
VBA:$56
0–2
SCI Idle Line
VBA:$58
0–2
SCI Timer
VBA:$5A
0–2
Reserved
VBA:$5C
0–2
Reserved
VBA:$5E
0–2
Reserved
VBA:$60
0–2
Host Receive Data Full
VBA:$62
0–2
Host Transmit Data Empty
VBA:$64
0–2
Host Command (Default)
VBA:$66
0–2
Reserved
VBA:$68
0–2
EFCOP Data Input Buffer Empty
VBA:$6A
0–2
EFCOP Data Output Buffer Full
VBA:$6C
0–2
Reserved
VBA:$6E
0–2
Reserved
:
:
VBA:$FE
0–2
Interrupt Source
:
Reserved
Table B-5. Interrupt Source Priorities Within an IPL
Priority
Interrupt Source
Level 3 (Nonmaskable)
Highest
Hardware RESET
Stack Error
Illegal Instruction
Debug Request Interrupt
Trap
Lowest
Non-Maskable Interrupt
Levels 0, 1, 2 (Maskable)
Highest
IRQA (External Interrupt)
IRQB (External Interrupt)
IRQC (External Interrupt)
IRQD (External Interrupt)
DMA Channel 0 Interrupt
DMA Channel 1 Interrupt
DMA Channel 2 Interrupt
DMA Channel 3 Interrupt
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-9
Programming Reference
Table B-5. Interrupt Source Priorities Within an IPL (Continued)
Priority
Interrupt Source
DMA Channel 4 Interrupt
DMA Channel 5 Interrupt
Host Command Interrupt
Host Transmit Data Empty
Host Receive Data Full
ESSI0 RX Data with Exception Interrupt
ESSI0 RX Data Interrupt
ESSI0 Receive Last Slot Interrupt
ESSI0 TX Data With Exception Interrupt
ESSI0 Transmit Last Slot Interrupt
ESSI0 TX Data Interrupt
ESSI1 RX Data With Exception Interrupt
ESSI1 RX Data Interrupt
ESSI1 Receive Last Slot Interrupt
ESSI1 TX Data With Exception Interrupt
ESSI1 Transmit Last Slot Interrupt
ESSI1 TX Data Interrupt
SCI Receive Data With Exception Interrupt
SCI Receive Data
SCI Transmit Data
SCI Idle Line
SCI Timer
Timer0 Overflow Interrupt
Timer0 Compare Interrupt
Timer1 Overflow Interrupt
Timer1 Compare Interrupt
Timer2 Overflow Interrupt
Timer2 Compare Interrupt
EFCOP Data Input Buffer Empty
Lowest
EFCOP Data Output Buffer Full
DSP56321 Reference Manual, Rev. 1
B-10
Freescale Semiconductor
Programming Sheets
B.3 Programming Sheets
Date:
Application:
Programmer:
Sheet 1 of 2
Carry
Overflow
Zero
Negative
Central Processor
Unnormalized ( U = Acc(47) xnor Acc(46) )
Extension
Limit
FFT Scaling ( S = Acc(46) xor Acc(45) )
Interrupt Mask
S(1:0)
I(1:0)
00
01
10
11
Scaling Mode
Scaling Mode
00
01
10
11
Exceptions Masked
None
IPL 0
IPL 0, 1
IPL 0, 1, 2
No scaling
Scale down
Scale up
Reserved
Sixteen-Bit Compatibilitity
Double Precision Multiply Mode
Loop Flag
DO-Forever Flag
Sixteen-Bit Arithmetic
Instruction Cache Enable
Arithmetic Saturation
Rounding Mode
CP(1:0)
00
01
10
11
Core Priority
Core Priority
0 (lowest)
1
2
3 (highest)
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
CP1
I0
S
L
E
U
N
Z
V
C
CP0
RM
SM
CE
*0
SA
FV
LF
DM
Extended Mode Register (EMR)
Status Register (SR)
Reset = $C00300
SC
*0
S1
S0
I1
Mode Register (MR)
Condition Code Register (CCR)
Read/Write
*= Reserved, Program as 0
Figure B-1. Status Register (SR)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-11
Programming Reference
Date:
Application:
Programmer:
Sheet 2 of 2
Central Processor
Chip Operating Mode, Bits 3–0
Refer to the operating modes
table in Chapter 4.
Asynchronous Bus Arbitration Enable, Bit 13
0 = Synchronization disabled
1 = Synchronization enabled
External Bus Disable, Bit 4
0 = Enables external bus
1 = Disables external bus
Address Attribute Priority Disable, Bit 14
0 = Priority mechanism enabled
1 = Priority mechanism disabled
Stop Delay Mode, Bit 6
0 = Delay is 128K clock cycles
1 = Delay is 16 clock cycless
Stack Extension X Y Select, Bit 16
0 = Mapped to X memory
1 = Mapped to Y memory
Stack Extension Underflow Flag, Bit 17
0 = No stack underflow
1 = Stack underflow
Core-DMA Priority, Bits 9–8
CPD[1:0]
Description
00
Compare SR[CP] to
active DMA channel
priority
01
DMA has higher
priority than core
10
DMA has same
priority as core
11
DMA has lower
priority than core
Stack Extension Overflow Flag, Bit 18
0 = No stack overflow
1 = Stack overflow
Stack Extension Wrap Flag, Bit 19
0 = No stack extension wrap
1 = Stack extension wrap (sticky bit)
Stack Extension Enable, Bit 20
0 = Stack extension disabled
1 = Stack extension enabled
Memory Switch Configuration, Bits 22–21, 7
Refer to the memory configurations in
Chapter 3.
Cache Burst Mode Enable, Bit 10
0 = Burst Mode disabled
1 = Burst Mode enabled
TA Synchronize Select, Bit 11
0 = Not synchronized
1 = Synchronized
Bus Release Timing, Bit 12
0 = Fast Bus Release mode
1 = Slow Bus Release mode
See Bits
22–21
23
*0
22
21 20 19 18 17 16 15 14 13 12 11 10 9
MSW2 MSW1 SEN WRP EOV EUN XYS
*0
8
7
6
APD ABE BRT TAS BE CPD1 CPD0 MSW0 SD
Operating Mode Register
Reset = $00030X; X = latched from the mode pins at reset
5
*0
4
3
2
1
0
EBD MD MC MB MA
* = Reserved, Program as 0
Figure B-2. Operating Mode Register (OMR)
DSP56321 Reference Manual, Rev. 1
B-12
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 1 of 2
CLKGEN
Division Factor Bits (DF[0–2])
DF2–DF0
Division Factor DF
$0
$1
$2
•
•
•
$7
PSTP and PEN Relationship
PSTP PEN
20
21
22
•
•
•
27
Operation During STOP
DPLL Oscillator (XTLD = 0)
Recovery Time
Power
from Stop
Consumption
State
During Stop State
0
1
0/1
0
Disabled
Disabled
Disabled
Enabled
Long
Short
Minimal
Low
1
1
Enabled
Enabled
Short
High
XTAL Disable Bit (XTLD)
0 = Enable XTAL Oscillator
1 = EXTAL Driven From
An External Source
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
*0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0
DPLL Clock Control (PCTL) Register
6
5
4
DF2
DF1
DF0
3
2
1
PEN XTLD PSTP
0
*0
X:$FFFFD1 Read/Write
Reset = $000000 or $000008 depending on value of PINIT
* = Reserved, Program as 0
Figure B-2. Digital Phase-Lock Loop Control (PCTL) Register
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-13
Programming Reference
Date:
Application:
Programmer:
Sheet 2 of 2
CLKGEN
Binary Rate Modulation Order (BRMO)
0 = Multiplication Factor Denominator (MFD) < 8
1 = Multiplication Factor Denominator (MFD) ≥ 8
Phase Lock Mode (PLM)
0 = Frequency Only Lock (FOL) mode
1 = Frequency and Phase Lock (FPL) mode
Multiplication Factor Denominator MFD[6–0]
MFD[6–0]
Multiplication Factor
Denominator (MFD)
$00
$01
$02
•
•
•
$7E
$7F
1
2
3
•
•
•
127
128
Multiplication Factor Numerator MFN[6–0]
MFN[6–0]
Multiplication Factor
Numerator (MFN]
$00
$01
$02
•
•
•
$7E
$7F
0
1
2
•
•
•
126
127
Multiplication Factor Integer (MFI[3–0])
MFI[3–0]
Multiplication Factor Integer (MFI)
$0
$1
$2
$3
$4
$5
$6
$7
•
•
•
$E
$F
Predivision Factor Bits (PD[3–0])
PD[3–0]
$0
$1
$2
•
•
•
$F
Predivision Factor (PDF)
1
2
3
•
•
•
16
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
6
5
5
5
5
5
5
6
7
•
•
•
14
15
5
4
3
2
1
0
BRMO PLM PDF3 PDF2 PDF1 PDF0 MFD6 MDF5 MFD4 MFD3 MFD2 MFD1 MFD0 MFN6 MFN5 MFN4 MFN3 MFN2 MFN1 MFN0 MFI3 MFI2 MFI1 MFI0
DPLL Static Control Register (DSCR)
Reset = $C00008
X:$FFFFD0 Read/Write
Note: If MFI = $F, MFN must be $00.
Figure B-3. DPLL Static Control Register (DSCR)
DSP56321 Reference Manual, Rev. 1
B-14
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 1 of 2
Bus Interface Unit
NOTE: All BCR bits are read/write control bits.
Default Area Wait Control, Bits 20–16
Bus Request Hold, Bit 23
Area 3 Wait Control, Bits 15–13
0 = BR pin is asserted only for attempted
or pending access
Area 2 Wait Control, Bits 12–10
1 = BR pin is always asserted
Area 1 Wait Control, Bits 9–5
Area 0 Wait Control, Bits 4– 0
These read/write control bits define
the number of wait states inserted
into each external SRAM access to
the designated area. The value of
these bits should not be programmed
as zero.
Bits
Bit Name
# of Wait States
Bus State, Bit 21
20–16
BDFW[4–0]
0–31
0 = DSP is not bus master
15–13
BA3W[2–0]
0–7
1 = DSP is bus master
12–10
BA2W[2–0]
0–7
9–5
BA1W[4–0]
0–31
4–0
BA0W[4–0]
0–31
23 22 21 20 19 18 17 16 15 14 13 12 11 10
BRH
*0
BBS
BDFW[4–0]
Bus Control Register (BCR)
Reset = $1FFFFF
BA3W[2–0]
BA2W[2–0]
9
8
7
6
BA1W[4–0]
5
4
3
2
1
0
BA0W[4–0]
X:$FFFFFB Read/Write
* = Reserved, Program as 0
Figure B-7. Bus Control Register (BCR)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-15
Programming Reference
Date:
Application:
Programmer:
Sheet 2 of 2
Bus Interface Unit
Bus Packing Enable, Bit 7
0 = Disable internal packing/unpacking logic
1 = Enable internal packing/unpacking logic
Bus Y Data Memory Enable, Bit 5
0 = Disable AA pin and logic during
external Y data space accesses
1 = Enable AA pin and logic during
external Y data space accesses
Bus Address to Compare, Bits 23–12
Bus X Data Memory Enable, Bit 4
0 = Disable AA pin and logic during
external X data space accesses
1 = Enable AA pin and logic during
external X data space accesses
BAC[11–0] = address to compare to the
external address in order to decide
whether to assert the AA pin
Bus Program Memory Enable, Bit 3
0 = Disable AA pin and logic during
external program space accesses
1 = Enable AA pin and logic during
external program space accesses
Bus Number of Address Bits to Compare, Bits 11–8
BNC[3–0] = number of bits (from BAC bits) that are
compared to the external address
Bus Address Attribute Polarity, Bit 2
0 = AA signal is active low
1 = AA signal is active high
(Combinations BNC[3–0] = 1111, 1110, 1101 are
reserved.)
Bus Access Type, Bits 1–0
BAT[1–0]
23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
Reserved
SRAM access
10
11
Reserved
Reserved
7
BAC11 BAC10 BAC9 BAC8 BAC7 BAC6 BAC5 BAC4 BAC3 BAC2 BAC1 BAC0 BNC3 BNC2 BNC1 BNC0 BPAC
Address Attribute Registers 3 (AAR3)
Address Attribute Registers 2 (AAR2)
Address Attribute Registers 1 (AAR1)
Address Attribute Registers 0 (AAR0)
Reset = $000000
Encoding
00
01
6
*0
5
4
3
2
1
0
BYEN BXEN BPEN BAAP BAT1 BAT0
X:$FFFFF6 Read/Write
X:$FFFFF7 Read/Write
X:$FFFFF8 Read/Write
X:$FFFFF9 Read/Write
= Reserved, Program as 0
*
Figure B-8. Address Attribute Registers (AAR[3–0])
DSP56321 Reference Manual, Rev. 1
B-16
Freescale Semiconductor
Programming Sheets
Date:
Programmer:
Application:
Sheet 1 of 1
DMA Interrupt Enable, Bit 22
0 = Disables DMA Interrupt
1 = Enables DMA interrupt
DMA Address Mode, Bits 9–4
Non-Three-Dimensional Addressing Modes (D3D=0)
DAM[2–0] = source
DAM[5–3] = Destination
DMA Transfer Mode, Bits 21–19
DTM[2:0]
Triggered By
DE Cleared
Transfer Mode
000
001
request
request
yes
yes
block transfer
word transfer
010
011
request
DE
yes
yes
line transfer
block transfer
100
101
request
request
no
no
block transfer
word transfer
110–111
reserved
DMA Channel Priority, Bits 18–17
DPR[1:0]
Channel Priority
00
01
Priority level 0 (lowest)
Priority level 1
10
11
Priority level 2
Priority level 3 (highest)
Requesting Device
00000–00011
External (IRQA, IRQB, IRQC, IRQD)
00100–01001
Transfer done from channel 0,1,2,3,4,5
01010–01011
ESSI0 Receive, Transmit Data
01100–01101
ESSI1 Receive, Transmit Data
01110–01111
SCI Receive, Transmit Data
10000–10010
Timer0, Timer1, Timer2
10011
Host Receive Data Full
10100
Host Transmit Data Empty
10101
EFCOP FDIBE = 1
10110
EFCOP FDOBF = 1
DAM[5–3]
000
001
010
011
100
101
110
111
DIE
DTM[2–0]
2D
2D
2D
2D
No update
Postincrement-by-1
reserved
DMA Control Registers (DCR5–DCR0)
Reset = $000000
Offset Register
Selection
DOR0
DOR1
DOR2
DOR3
None
None
B
B
B
B
A
A
Addressing Mode
2D
2D
2D
2D
No update
Postincrement-by-1
3D
3D
Offset Selection
DOR0
DOR1
DOR2
DOR3
None
None
DOR[0–1]
DOR[2–3]
Addressing Mode
Offset Selection
Source: 3D
Source: DOR[0–1]
Destination: Defined by DAM[5–3]
Source: Defined by DAM[5–3]
Destination: 3D
Destination: DOR[2–3]
DMA Destination Space, Bits 3–2
DSS[1:0]
00
DMA Destination Memory
X Memory Space
01
10
Y Memory Space
P Memory Space
11
Reserved
DMA Source Space, Bits 1–0
DSS[1:0]
Reserved
DPR[1–0] DCON
Counter
Mode
DAM Counter
DCO Layout
[1–0]
00
Mode C
DCOH[23–12]
DCOM[11–6] DCOL[5–0]
01
Mode D DCOH[23–18]
DCOM[17–6]
DCOL[5–0]
10
Mode E DCOH[23–18] DCOM[17–12]
DCOL[11–0]
11
—
Reserved
23 22 21 20 19 18 17 16 15 14 13 12 11 10
DE
Addressing Mode
Three-Dimensional Addressing Modes (D3D=1)
1
DMA Request Source, Bits 15–11
DRS[4:0]
DAM[5–3]
DAM[2–0]
000
001
010
011
100
101
110–111
DAM2
0
DMA Continuous Mode Enable, Bit 16
0 = Disables continuous mode
1 = Enables continuous mode
10111 - 11111
DMA
Three-Dimensional Mode, Bit 10
0 = Three-Dimensional mode disabled
1 = Three-Dimensional mode enabled
DMA Channel Enable, Bit 23
0 = Disables channel operation
1 = Enables channel operation
DRS[4–0]
D3D
9
8
7
DMA Source Memory
00
01
X Memory Space
Y Memory Space
10
11
P Memory Space
Reserved
6
5
4
DAM[5–0]
3
2
DDS[1–0]
1
0
DSS[1–0]
X:$FFFFD8, X:$FFFFDC, X:$FFFFE0,
X:$FFFFE4, X:$FFFFE8, X:$FFFFEC Read/Write
Figure B-4. DMA Control Registers 5–0 (DCR[5–0])
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-17
Programming Reference
Date:
Application:
Programmer:
Sheet 1 of 5
HOST
Host Transmit Data (usually Loaded by program)
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
Transmit High Byte
8
7
Transmit Middle Byte
Host Transmit Data Register (HTX)
Reset = empty
6
5
4
3
2
1
0
Transmit Low Byte
X:$FFFFC7 Write Only
Figure B-5. Host Transmit Data Register
DSP56321 Reference Manual, Rev. 1
B-18
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 2 of 5
15
HOST
8
*0 *0
7
BA10
6
5
4
3
2
1
0
BA9
BA8
BA7
BA6
BA5
BA4
BA3
Host Base Address Register (HBAR) X:$FFFFC5 Read/Write
Reset = $80
Host Request Open Drain
HDRQ
HROD
HREN/HEW
0
0
1
1
0
1
0
1
1
1
1
1
Host GPIO Port Enable
0 = GPIO Pins Disable, 1 = GPIO Pin Enable
Host Address Line 8 Enable
0 → HA8 = GPIO, 1 → HA8 = HA8
Host Address Line 9 Enable
0 → HA9 = GPIO, 1 → HA9 = HA9
Host Data Strobe Polarity
0 = Strobe Active Low, 1 = Strobe Active High
Host Chip Select Enable
0 → HCS/HAI0 = GPIO,
1 → HCS/HA10 = HC8, if HMUX = 0
1 → HCS/HA10 = HC10, if HMUX = 1
Host Address Strobe Polarity
0 = Strobe Active Low, 1 = Strobe Active High
Host Multiplexed Bus
0 = Nonmultiplexed, 1 = Multiplexed
Host Request Enable
0 → HREQ/HACK = GPIO,
1 → HREQ = HREQ, if HDRQ = 0
Host Dual Data Strobe
0 = Singles Stroke, 1 = Dual Stoke
Host Chip Select Polarity
0 = HCS Active Low
HTRQ & HRRQ Enable
1 = HCS Active High
HDRQ
0
0
1
1
Host Acknowledge Enable
0 → HACK = GPIO
If HDRQ & HREN = 1,
HACK = HACK
Host Request Priority
HRP
0
1
0
1
Host Enable
0 → HI08 Disable
Pins = GPIO
1 → HI08 Enable
HREQ Active Low
HREQ Active High
HTRQ,HRRQ Active Low
HTRQ,HRRQ Active High
Host Acknowledge Priority
0 = HACK Active Low, 1 = HACK Active High
15
HAP
14
13
12
HRP
HCSP
HDDS HMUX
11
10
9
8
7
6
5
HASP
HDSP
HROD
*0
HEN
HAEN
Host Port Control Register (HPCR)
Reset = $00
4
3
2
1
0
HREN HCSEN HA9EN HA8EN HGEN
X:$FFFFC4 Read/Write
* = Reserved, Program as 0
Figure B-6. Host Base Address and Host Port Control Registers
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-19
Programming Reference
Date:
Application:
Programmer:
Sheet 3 of 5
HOST
Host Receive Interrupt Enable
0 = Disable 1 = Enable if HRDF = 1
Host Transmit Interrupt Enable
0 = Disable 1 = Enable if HTDE = 1
Host Command Interrupt Enable
0 = Disable 1 = Enable if HCP = 1
Host Flag 2
Host Flag 3
15 7
6
5
*0 *0 *0 *0
4
3
HF3
HF2
2
1
0
HCIE HTIE
Host Control Register (HCR)
Reset = $0
HRIE
X:$FFFFC2 Read /Write
*= Reserved, Program as 0
Figure B-7. Host Control Register
DSP56321 Reference Manual, Rev. 1
B-20
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 4 of 5
Host Side
HOST
Receive Request Enable
DMA Off
0 = Interrupts Disabled
DMA On
0 = Host → DSP
1 = Interrupts Enabled
1 = DSP → Host
Transmit Request Enable
DMA Off
0 = Interrupts Disabled
DMA On
0 = DSP → Host
1 = Interrupts Enabled
1 = Host → DSP
HDRQ
0
HREQ/HTRQ
HREQ
HACK/HRRQ
HACK
1
HTRQ
HRRQ
Host Flags
Write Only
Host Little Endian
Initialize (Write Only)
0 = No Action
1 = Initialize DMA
7
6
5
4
3
INIT
*0
HLEND
HF1
HF0
Interrupt Control Register (ICR)
Reset = $00
2
1
0
HDRQ TREQ RREQ
Host Address: $0 Read/Write
Host Vector
Contains Host Command Interrupt Address ÷ 2
Host Command
Handshakes Executing Host Command Interrupts
Contains the host command interrupt address
7
6
5
4
3
2
1
0
HC7
HC6
HC5
HC4
HC3
HC2
HC1
HC0
Command Vector Register (CVR)
Reset = $32
Host Address: $1 Read/Write
*= Reserved, Program as 0
Figure B-8. Interrupt Control and Command Vector Registers
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-21
Programming Reference
Date:
Application:
Programmer:
Sheet 5 of 5
HOST
Host Side
7
6
5
4
3
2
1
0
IV7
IV6
IV5
IV4
IV3
IV2
IV1
IV0
Contains the interrupt vector or number
Interrupt Vector Register (IVR)
Reset = $0F
Host Address: $3 Read/Write
Host Transmit Data (usually loaded by program)
7
0 7
Transmit Low Byte
0 7
Transmit Middle Byte
0 7
Not Used
0
$7
Transmit Byte Registers
Reset = $00
$6
0
Transmit High Byte
$5
0
0
0
0
0
0
0
$4
Host Addresses: $7, $6, $5, $4 Write Only
Figure B-9. Interrupt Vector and Host Transmit Data Registers
DSP56321 Reference Manual, Rev. 1
B-22
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 1 of 3
ESSI
Select SC1 as Tx#0 drive
enable
0 = SC1 functions as
serial I/O flag
1 = functions as driver
enable of Tx#0
external buffer
Word Length Control
WL0
Number of bits/word
WL2
WL1
0
0
0
0
0
1
8
12
0
0
1
1
0
1
16
24
1
1
0
0
0
1
32 (data in first 24 bits)
32 (data in last 24 bits)
1
1
1
1
0
1
Reserved
Reserved
Alignment Control
0 = 16-bit data left aligned to bit 23
1 = 16-bit data left aligned to bit 15
Frame Rate Divider Control
DC4:0 = $00-$1F (1 to 32)
Divide ratio for Normal mode
# of time slots for Network
The combination of PSR = 1 and PM[7:0] = $00 is forbidden
Prescaler Range
0 = divide by 8
1 = divide by 1
23 22 21 20 19 18 17 16 15 14 13 12 11 10
*0
SSC1 WL2
WL1
WL0
ALC
*0
DC4
DC3 DC2
DC1
DC0
PSR
9
Prescale Modulus Select
PM[7–0] = $00-$FF (divide by 1 to 256)
8
*0 *0 *0
7
6
PM7 PM6
5
PM5
4
3
PM4 PM3
2
1
PM2 PM1
0
PM0
ESSI Control Register A (CRAx) ESSI0—X:$FFFFB5 Read/Write
Reset = $000000
ESSI1—X:$FFFFA5 Read/Write
* = Reserved, Program as 0
Figure B-10. ESSI Control Register A (CRA)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-23
Programming Reference
Date:
Application:
Programmer:
Sheet 2 of 3
ESSI
Clock Polarity
(clk edge data & Frame Sync clocked out/in)
0 = out on rising/in on falling
1 = in on rising/out on falling
Receive Exception Interrupt Enable
0 = Disable
1 = Enable
Transmit Exception Interrupt Enable
0 = Disable
1 = Enable
Frame Sync Polarity
0 = high level (positive)
1 = low level (negative)
Receive Last Slot Interrupt Enable
0 = Disable
1 = Enable
Frame Sync Relative Timing
(WL Frame Sync only)
0 = with first data bit
1 = 1 clock cycle earlier than first data bit
Transmit Last Slot Interrupt Enable
0 = Disable
1 = Enable
Receive Interrupt Enable
0 = Disable
1 = Enable
Transmit Interrupt Enable
0 = Disable
1 = Enable
Receiver Enable
0 = Disable
1 = Enable
Transmit 0 Enable
0 = Disable
1 = Enable
Transmit 1 Enable (SYN=1 only)
0 = Disable
1 = Enable
Transmit 2 Enable (SYN=1 only)
0 = Disable
1 = Enable
FSL0
0
0
TX
Word
RX
Word
0
1
1
0
Bit
Bit
Word
Bit
1
1
Word
Bit
Shift Direction
0 = MSB First
Clock Source Direction
0 = External Clock 1 = Internal Clock
1 = Network
Sync/Async Control
(Tx & Rx transfer together or not)
0 = Asynchronous
1 = Synchronous
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
RIE
TIE
1 = LSB First
Serial Control Direction Bits (see Table 8-4)
Mode Select
0 = Normal
REIE TEIE RLIE TLIE
Frame Sync
Length
FSL1
RE
TE0
TE1
ESSI Control Register B (CRBx)
Reset = $000000
Pin
SC0
SCDx = 0 (Input)
Rx Clk
SCDx = 1 (Output)
Flag 0
SC1
SC2
Rx Frame Sync
Tx Frame Sync
Flag 1
Tx, Rx Frame Sync
Output Flag x
If SYN = 1 and SCD1 = 1
OFx → SCx Pin
8
7
6
5
4
3
2
1
0
TE2 MOD SYN CKP FSP FSR FSL1 FSL0 SHFD SCKD SCD2 SCD1 SCD0 OF1 OF0
ESSI0—X:$FFFFB6 Read/Write
ESSI1—X:$FFFFA6 Read/Write
Figure B-11. ESSI Control Register B (CRB)
DSP56321 Reference Manual, Rev. 1
B-24
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 3 of 3
ESSI
23
SSI Transmit Slot Mask
0 = IgnoreTime Slot
1 = Active Time Slot
16 15 14 13 12 11 10
*0 *0
ESSI Transmit Slot Mask A (TSMA[0–1])
Reset = $FFFF
23
SSI Transmit Slot Mask
0 = IgnoreTime Slot
1 = Active Time Slot
SSI Receive Slot Mask
0 = IgnoreTime Slot
1 = Active Time Slot
SSI Receive Slot Mask
0 = Ignore Time Slot
1 = Active Time Slot
5
4
3
2
1
0
TS5
TS4
TS3
TS2
TS1
TS0
4
3
2
1
0
8
7
6
5
9
8
7
6
5
4
RS8
RS7
RS6
RS5
RS4
3
2
RS3 RS2
1
0
RS1
RS0
1
0
ESSI0—X:$FFFFB2 Read/Write
ESSI1—X:$FFFFA2 Read/Write
16 15 14 13 12 11 10
*0 *0
9
RS15 RS14 RS13 RS12 RS11 RS10 RS9
ESSI Receive Slot Mask A (RSMA[0–1]
Reset = $FFFF
23
6
TS6
ESSI0—X:$FFFFB3 Read/Write
ESSI1—X:$FFFFA3 Read/Write
16 15 14 13 12 11 10
*0 *0
7
TS7
TS31 TS30 TS29 TS28 TS27 TS26 TS25 TS24 TS23 TS22 TS21 TS20 TS19 TS18 TS17 TS16
ESSI Transmit Slot Mask B (TSMB[0–1])
Reset = $FFFF
23
8
TS8
ESSI0—X:$FFFFB4 Read/Write
ESSI1—X:$FFFFA4 Read/Write
16 15 14 13 12 11 10
*0 *0
9
TS15 TS14 TS13 TS12 TS11 TS10 TS9
9
8
7
6
5
4
3
2
RS31 RS30 RS29 RS28 RS27 RS26 RS25 RS24 RS23 RS22 RS21 RS20 RS19 RS18 RS17 RS16
ESSI Receive Slot Mask B (RSMB[0–1])
Reset = $FFFF
ESSI0—X:$FFFFB1 Read/Write
ESSI1—X:$FFFFA1 Read/Write
* = Reserved, Program as 0
Figure B-12. ESSI Transmit and Receive Slot Mask Registers (TSM, RSM)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-25
Programming Reference
Date:
Application:
Programmer:
Sheet 1 of 2
SCI
Word Select Bits
0 0 0 = 8-bit Synchronous Data (Shift Register Mode)
0 0 1 = Reserved
0 1 0 = 10-bit Asynchronous (1 Start, 8 Data, 1 Stop)
0 1 1 = Reserved
1 0 0 = 11-bit Asynchronous (1 Start, 8 Data, Even Parity, 1 Stop)
1 0 1 = 11-bit Asynchronous (1 Start, 8 Data, Odd Parity, 1 Stop)
1 1 0 = 11-bit Multidrop (1 Start, 8 Data, Data Type, 1 Stop)
1 1 1 = Reserved
Transmitter Enable
0 = Transmitter Disable
1 = Transmitter Enable
Idle Line Interrupt Enable
0 = Idle Line Interrupt Disabled
1 = Idle Line Interrupt Enabled
Receive Interrupt Enable
0 = Receive Interrupt Disabled
1 = Idle Line Interrupt Enabled
SCI Shift Direction
0 = LSB First
1 = MSB First
Receiver Wakeup Enable
0 = receiver has awakened
1 = Wakeup function enabled
Transmit Interrupt Enable
0 = Transmit Interrupts Disabled
1 = Transmit Interrupts Enabled
Wired-Or Mode Select
1 = Multidrop
0 = Point to Point
Timer Interrupt Enable
0 = Timer Interrupts Disabled
1 = Timer Interrupts Enabled
Send Break
0 = Send break, then revert
1 = Continually send breaks
Receiver Enable
0 = Receiver Disabled
1 = Receiver Enabled
SCI Timer Interrupt Rate
0 = ÷ 32, 1 = ÷ 1
Wakeup Mode Select
0 = Idle Line Wakeup
1 = Address Bit Wakeup
SCI Clock Polarity
0 = Clock Polarity is Positive
1 = Clock Polarity is Negative
SCI Receive Exception Inerrupt
0 = Receive Interrupt Disable
1 = Receive Interrupt Enable
23
*0
16 15 14 13 12 11 10 9
REIE SCKP STIR TMIE
TIE
RIE
SCI Control Register (SCR)
Reset $000000
ILIE
TE
8
RE
7
6
5
4
3
2
1
0
WOMS RWU WAKE SBK SSFTD WDS2 WDS1 WDS0
X:$FFFF9C Read/Write
* = Reserved, Program as 0
Figure B-13. SCI Control Register (SCR)
DSP56321 Reference Manual, Rev. 1
B-26
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 2 of 2
SCI
Clock Divider Bits (CD11–CD0)
TCM
RCM
TX Clock
RX Clock
SCLK Pin
Mode
0
0
0
1
Internal
Internal
Internal
External
Output
Input
Synchronous/Asynchronous
Asynchronous only
CD11–CD0
$000
Icyc Rate
Icyc /1
1
1
0
1
External
External
Internal
External
Input
Input
Asynchronous only
Synchronous/Asynchronous
$001
$002
Icyc /2
Icyc /3
•
•
•
•
•
$FFE
•
Icyc/4095
$FFF
Icyc/4096
Transmitter Clock Mode/Source
0 = Internal clock for Transmitter
1 = External clock from SCLK
Receiver Clock Mode/Source
0 = Internal clock for Receiver
1 = External clock from SCLK
Clock Out Divider
0 = Divide clock by 16 before feed to SCLK
1 = Feed clock to directly to SCLK
SCI Clock Prescaler
0 = ÷1 1 = ÷ 8
23
15 14 13 12 11 10
*0
TCM RCM
SCP
9
COD CD11 CD10 CD9
8
7
6
5
4
3
2
1
0
CD8
CD7
CD6
CD5
CD4
CD3
CD2
CD1
CD0
SCI Clock Control Register (SCCR)
Reset = $000000
Address X:$FFFF9B Read/Write
*= Reserved, Program as 0
Figure B-14. SCI Clock Control Registers (SCCR)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-27
Programming Reference
Date:
Application:
Programmer:
Sheet 1 of 3
Timers
PS (1–0)
Prescaler Clock Source
00
01
Internal CLK/2
TIO0
10
11
TIO1
TIO2
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
*0
PS1
8
7
6
5
4
3
2
1
0
PS0
Prescaler Preload Value (PL [20–0])
Timer Prescaler Load Register (TPLR)
Reset = $000000
X:$FFFF83 Read/Write
*= Reserved, Program as 0
Figure B-15. Timer Prescaler Load Register (TPLR)
DSP56321 Reference Manual, Rev. 1
B-28
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 2 of 3
Inverter Bit 8
0 = 0- to-1 transitions on TIO input increment the counter,
or high pulse width measured, or high pulse output on TIO
Timers
1 = 1-to-0 transitions on TIO input increment the counter,
or low pulse width measured, or low pulse output on TIO
Timer Reload Mode Bit 9
0 = Timer operates as a free
running counter
1 = Timer is reloaded when
selected condition occurs
Timer Control Bits 4–7 (TC[3–0])
TIO
Clock
Mode
TC (3:0)
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Direction Bit 11
0 = TIO pin is input
1 = TIO pin is output
Data Input Bit 12
0 = Zero read on TIO pin
1 = One read on TIO pin
Data Output Bit 13
0 = Zero written to TIO pin
1 = One written to TIO pin
GPIO
Output
Output
Input
Input
Input
Input
Output
–
Output
Output
–
–
–
–
–
Internal
Internal
Internal
External
Internal
Internal
Internal
Internal
–
Internal
Internal
–
–
–
–
–
Timer
Timer Pulse
Timer Toggle
Event Counter
Input Width
Input Period
Capture
Pulse Width Modulation
Reserved
Watchdog Pulse
Watchdog Toggle
Reserved
Reserved
Reserved
Reserved
Reserved
Timer Enable Bit 0
0 = Timer Disabled
1 = Timer Enabled
Prescaled Clock Enable Bit 15
0 = Clock source is CLK/2 or TIO
1 = Clock source is prescaler output
Timer Overflow Interrupt Enable Bit 1
0 = Overflow Interrupts Disabled
1 = Overflow Interrupts Enabled
Timer Compare Flag Bit 21
0 = “1” has been written to TCSR(TCF),
or timer compare interrupt serviced
Timer Compare Interrupt Enable Bit 2
0 = Compare Interrupts Disabled
1 = Compare Interrupts Enabled
1 = Timer Compare has occurred
Timer Overflow Flag Bit 20
0 = “1” has been written to TCSR(TOF),
or timer Overflow interrupt serviced
1 = Counter wraparound has occurred
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
*0 *0
TCF
TOF
*0 *0 *0 *0
PCE
*0
DO
DI
DIR
*0
8
TRM INV
7
6
5
4
3
TC3
TC2
TC1
TC0
*0
2
1
TCIE TQIE
0
TE
Timer Control/Status Register TCSR0:$FFFF8F Read/Write
Reset = $000000
TCSR1:$FFFF8B Read/Write
TCSR2:$FFFF87 Read/Write
*= Reserved, Program as 0
Figure B-16. Timer Control/Status Register (TCSR)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-29
Programming Reference
Date:
Application:
Programmer:
Sheet 3 of 3
Timers
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
Timer Reload Value
Timer Load Register (TLR[0–2])
Reset = $xxxxxx, value is indeterminate after reset
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
TLR0—X:$FFFF8E Write Only
TLR1—X:$FFFF8A Write Only
TLR2—X:$FFFF86 Write Only
8
7
6
5
4
3
2
1
0
Value Compared to Counter Value
TCPR0—X:$FFFF8D Read/Write
TCPR1—X:$FFFF89 Read/Write
TCPR2—X:$FFFF85 Read/Write
Timer Compare Register (TCPR[0–2])
Reset = $xxxxxx, value is indeterminate after reset
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
Timer Count Value
Timer Count Register (TCR[0–2])
Reset = $000000
TCR0—X:$FFFF8C Read Only
TCR1—X:$FFFF88 Read Only
TCR2—X:$FFFF84 Read Only
Figure B-22. Timer Load, Compare, and Count Registers (TLR, TCPR, TCR)
DSP56321 Reference Manual, Rev. 1
B-30
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 1 of 4
GPIO
Port B (HI08)
DRx = 1 → HIx is Output
DRx = 0 → HIx is Input
15
DR15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
DR14
DR13
DR12
DR11
DR10
DR9
DR8
DR7
DR6
DR5
DR4
DR3
DR2
DR1
DR0
Host Data Direction Register (HDDR)
Reset = $00
X:$FFFFC8 Write
DRx holds value of corresponding HI08 GPIO pin.
Function depends on HDDR.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Host Data Register (HDR)
Reset = Undefined
X:$FFFFC9 Write
Figure B-17. Host Data Direction and Host Data Registers (HDDR, HDR)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-31
Programming Reference
Date:
Application:
Programmer:
Sheet 2 of 4
GPIO
Port C (ESSI0)
PCn = 1 → Port Pin configured as ESSI
PCn = 0 → Port Pin configured as GPIO
23 6
5
4
3
2
1
0
*0 *0
PCC5
PCC4
PCC3
PCC2
PCC1
Port C Control Register (PCRC)
Reset = $000000
PDCn = 1 → Port Pin is Output
PDCn = 0 → Port Pin is Input
23 6
5
4
3
2
1
*0 *0
PRC5
PRC4
PRC3
PRC2
PRC1
Port C Direction Register (PRRC)
Reset = $000000
PCC0
X:$FFFFBF Read/Write
0
PRC0
X:$FFFFBE Read/Write
if port pin n is GPIO input, then PDn reflects the
value on port pin n
if port pin n is GPIO output, then value written to
PDn is reflected on port pin n
23
6
*0 *0
5
4
PDC5
PDC4
3
PDC3
2
PDC2
1
PDC1
0
PDC0
Port C GPIO Data Register (PDRC) X:$FFFFBD Read/Write
Reset = $000000
*= Reserved, Program as 0
Figure B-18. Port C Registers (PCRC, PRRC, PDRC)
DSP56321 Reference Manual, Rev. 1
B-32
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 3 of 4
GPIO
Port D (ESSI1)
PCn = 1 → Port Pin configured as ESSI
PCn = 0 → Port Pin configured as GPIO
23 6
5
4
3
2
1
0
*0 *0
PCD5
PCD4
PCD3
PCD2
PCD1
Port D Control Register (PCRD)
Reset = $000000
PDCn = 1 → Port Pin is Output
PDCn = 0 → Port Pin is Input
23 6
5
4
3
2
1
*0 *0
PRD5
PRD4
PRD3
PRD2
PRD1
Port D Direction Register (PRRD)
Reset = $000000
PCD0
X:$FFFFAF Read/Write
0
PRD0
X:$FFFFAE Read/Write
if port pin n is GPIO input, then PDn reflects the
value on port pin n
if port pin n is GPIO output, then value written to
PDn is reflected on port pin n
23
6
*0 *0
5
4
PDD5
PDD4
3
PDD3
2
PDD2
1
PDD1
0
PDD0
Port D GPIO Data Register (PDRD) X:$FFFFAD Read/Write
Reset = $000000
*= Reserved, Program as 0
Figure B-19. Port D Registers (PCRD, PRRD, PDRD)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-33
Programming Reference
Date:
Application:
Programmer:
Sheet 4 of 4
GPIO
Port E (SCI)
PCn = 1 → Port Pin configured as ESSI
PCn = 0 → Port Pin configured as GPIO
23 6
5
4
3
2
1
0
*0 *0 *0 *0 *0
PCE2
PCE1
Port E Control Register (PCRE)
Reset = $000000
PDCn = 1 → Port Pin is Output
PDCn = 0 → Port Pin is Input
23 6
5
4
3
2
1
*0 *0 *0 *0 *0
PRE2
PRE1
Port E Direction Register (PRRE)
Reset = $000000
PCE0
X:$FFFF9F Read/Write
0
PRE0
X:$FFFF9E Read/Write
if port pin n is GPIO input, then PDn reflects the
value on port pin n
if port pin n is GPIO output, then value written to
PDn is reflected on port pin n
23
6
5
4
3
*0 *0 *0 *0 *0
2
PDE2
1
PDE1
Port E GPIO Data Register (PDRE)
Reset = $000000
0
PDE0
X:$FFFF9D Read/Write
*= Reserved, Program as 0
Figure B-20. Port E Registers (PCRE, PRRE, PDRE)
DSP56321 Reference Manual, Rev. 1
B-34
Freescale Semiconductor
Programming Sheets
Date:
Application:
Programmer:
Sheet 1 of 2
EFCOP
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
*0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0
7
6
5
4
3
2
1
0
Filter Count Value
Filter Count Register (FCNT) Y:$FFFFB3 Read/Write
Reset = $000000
Filter Enable Bit 0
0 = EFCOP Disabled
1 = EFCOP Enabled
FilterData Input Interrupt Enable Bit 10
(Read/write control bit)
0 = Interrupt disabled
1 = Interrupt enabled
Filter Type Bit 1
0 = FIR
1 = IIR
FilterData Output Interrupt Enable Bit 11
(Read/write control bit)
0 = Interrupt disabled
1 = Interrupt enabled
FilterSaturation Bit 12
(Read only status bit)
0 = No FMAC underflow/overflow
1 = FMAC underflow/overflow occurred
FilterContention Bit 13
(Read only status bit)
0 = No dual access occurred
1 = Core and EFCOP tried to access
the same bank in FDM or FCM
Adaptive Mode Enable Bit 2
0 = Adaptive Mode Disabled
1 = Adaptive Mode Enabled
Update Mode Enable Bit 3
0 = Update Mode Disabled
1 = Update Mode Enabled
Filter Operating ModeBits 5–4
00 = Real
10 = Alt. Complex
01 = Complex 11 = Magnitude
Channels Bit 6
0 = Single channel
1 = Multichannel
Initialization Bit 7
0 = Preprocess initialization
1 = No initialization
Filter Data Input Buffer Empty Bit 14
(Read only status bit)
0 = FDIR is not empty
1 = FDIR is empty
Coefficients Bit 8
0 = Not shared
1 = Shared
Filter Data Output Buffer Full Bit 15
(Read only status bit)
0 = FDOR is not full
1 = FDOR is full
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
*0 *0 *0 *0 *0 *0 *0 *0
FD
FD
F
FSAT FDOE FDIE
OBF IBE CONT
*0
8
7
6
5
4
3
2
1
FSCO FPCR FMLC FOM1FOM0 FUPD FADP FLT
0
FEN
EFCOP Control Status Register (FCSR)Y:$FFFFB4 Read/Write
Reset = $000000
* = Reserved, Program as 0
Figure B-21. EFCOP Counter and Control Status Registers (FCNT and FCSR)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
B-35
Programming Reference
Date:
Application:
Programmer:
Sheet 2 of 2
EFCOP
Saturation Mode Bit 4
0 = Disabled 1 = Enabled
Sixteen-bit Arithmetic Mode Bit 5
0 = Disabled 1 = Enabled
Filter Rounding Mode Bits 3–2
00 = Convergent
01 = Two’s complement
10 = Truncation
11 = Reserved
Filter Scaling Bits 1–0
00 = × 1 10 = × 16
01 = × 8 11 = Reserved
Filter Input Scaling Bit 6
0 = Not used 1 = Used
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
6
*0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0 *0
EFCOP ALU Control Register (FACR)
Reset = $000000
5
4
FISL FSA FSM
3
2
Rounding
Mode
1
0
Filter
Scaling
Y:$FFFFB5 Read/Write
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
Data Base Address (FDM Pointer)
EFCOP Data Base Address (FDBA)
Reset = $000000
15 14 13 12 11 10 9
8
7
Y:$FFFFB6 Read/Write
6
5
4
3
2
1
0
Coefficient Base Address (FDM Pointer)
EFCOP Coefficient Base Address (FCBA)
Reset = $000000
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8
Filter Deci0 0 0 0 0 0 0 0 0 0 0 0 mation Value
************
EFCOP Decimation/Channel Count Register (FDCH)
Reset = $000000
7
6
*0 *0
Y:$FFFFB7 Read/Write
5
4
3
2
1
0
Filter Channels Value
Y:$FFFFB8 Read/Write
* = Reserved, Program as 0
Figure B-22. EFCOP FACR, FDBA, FCBA, and FDCH Registers
DSP56321 Reference Manual, Rev. 1
B-36
Freescale Semiconductor
Index
A
adder
modulo 1-7
offset 1-7
reverse-carry 1-7
Address Arithmetic Logic Unit (Address ALU) 1-7
Address Attribute Priority Disable (APD) bit 4-11
Address Attribute Registers (AAR) 4-18, 4-20
Bus Access Type (BAT) 4-22
Bus Address Attribute Polarity (BAAP) 4-22
Bus Address to Compare (BAC) 4-20
Bus Number of Address Bits to Compare (BNC) 4-21
Bus Packing Enable (BPAC) 4-21
Bus Program Memory Enable (BPEN) 4-21
Bus X Data Memory Enable (BXEN) 4-21
Bus Y Data Memory Enable (BYEN) 4-21
programming sheet B-18
Address Generation Unit (AGU) 1-7
Address Mode Wakeup 9-3
Address Trace Enable (ATE) bit 4-10
addressing modes 1-7
Alignment Control (ALC) bit 8-14
applications 1-5
Arithmetic Saturation Mode (SM) bit 4-5
Asynchronous Bus Arbitration Enable (ABE) bit 4-11
asynchronous data transfer 9-2
Asynchronous mode 8-9, 9-2, 9-13, 9-15, 9-16
Asynchronous Multidrop mode 9-15
B
barrel shifter 1-6
Binary Rate Modulation Order (BRMO) bit 5-8
bit-oriented instructions (BCHG, BCLR, BSET, BTST,
BRCLR, BRSET, BSCLR, BSSET, JCLR, JSET, JSCLR,
AND JSSET) 6-1
bootstrap 3-1, 3-2, 4-3
code 9-7
mode 4-3
program 4-3
program options, invoking 4-3
bootstrap ROM 1-4
Boundary Scan Register (BSR) 4-28
Burst Mode Enable (BE) bit 4-11
bus
address 2-2
data 2-2
external address 2-4
external data 2-4
internal 1-10
multiplexed 2-2
non-multiplexed 2-2
Bus Access Type (BAT) bits 4-22
Bus Address Attribute Polarity (BAAP) bit 4-22
Bus Address to Compare (BAC) bits 4-20
Bus Area 0 Wait State Control (BA0W) bits 4-20
Bus Area 1 Wait State Control (BA1W) bits 4-20
Bus Area 2 Wait State Control (BA2W) bits 4-19
Bus Area 3 Wait State Control (BA3W) bits 4-19
Bus Control Register (BCR) 4-18
bit definitions 4-19
Bus Area 0 Wait State Control (BA0W) 4-20
Bus Area 1 Wait State Control (BA1W) 4-20
Bus Area 2 Wait State Control (BA2W) 4-19
Bus Area 3 Wait State Control (BA3W) 4-19
Bus Default Area Wait State Control (BDFW) 4-19
Bus Lock Hold (BLH) bit 4-19
Bus Request Hold (BRH) 4-19
Bus State (BBS) bit 4-19
programming sheet B-17
Bus Default Area Wait State Control (BDFW) bits 4-19
Bus Interface Unit (BIU)
Address Attribute Registers (AAR) 4-18
Bus Control Register (BCR) 4-18
DRAM Control Register (DCR) 4-18
Bus Number of Address Bits to Compare (BNC) bits 4-21
Bus Packing Enable (BPAC) bit 4-21
Bus Program Memory Enable (BPEN) bit 4-21
Bus Release Timing (BRT) bit 4-11
Bus Request Hold (BRH) bit 4-19
Bus X Data Memory Enable (BXEN) bit 4-21
Bus Y Data Memory Enable (BYEN) bit 4-21
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-1
Index
C
Cache Burst Mode Enable (BE) bit 4-11
Cache Enable (CE) bit 4-5, 4-6
Carry (C) bit 4-9
cellular base station 11-1
Central Processing Unit (CPU) 1-1
Chip Operating Mode (MD–MA) bits 4-12
chip-select
logic 7-16
signal 7-3
CLKGEN 5-3
Clock
acronyms 5-2
configuration 5-1
external pins 5-3
generation diagram 5-1
Global Clock Generator 5-6
clock 2-4
Clock Divider (CD) bits 9-17
clock generator 8-10, 8-16
Clock Generator (CLKGEN) 5-1
programming model 5-6
Clock Out Divider (COD) bit 9-17
Clock Polarity (CKP) bit 8-20
Clock Prescaler (SCP) 9-17
Clock Source Direction (SCKD) bit 8-21
codec 8-3, 8-9, 8-11
COM byte 4-9
Command Vector Register (CVR) 7-21, 7-24
Host Command (HC) 7-25
Host Vector (HV) 7-25
programming sheet B-23
Condition Code Register (CCR) 4-5
Carry (C) 4-9
Extension (E) 4-8
Limit (L) 4-8
Negative (N) 4-8
Overflow (V) 4-9
Scaling (S) 4-8
Unnormalized (U) 4-8
Zero (Z) 4-9
Control Register A (CRA)
Alignment Control (ALC) 8-14
Frame Rate Divider Control (DC) 8-15
Prescale Modulus Select (PM) 8-15
Prescaler Range (PSR) 8-15
programming sheet B-25
Select SC1 (SSC1) 8-13
Word Length Control (WL) 8-14
Control Register B (CRB)
Clock Polarity (CKP) 8-20
Clock Source Direction (SCKD) 8-21
Frame Sync Length (FSL) 8-20
Frame Sync Polarity (FSP) 8-20
Frame Sync Relative Timing (FSR) 8-20
Mode Select (MOD) 8-20
programming sheet B-26
Receive Enable (RE) 8-19
Receive Exception Interrupt Enable (REIE) 8-18
Receive Interrupt Enable (RIE) 8-18
Receive Last Slot Interrupt Enable (RLIE) 8-18
Serial Control Direction 0 (SCD0) 8-21
Serial Control Direction 1 (SCD1) 8-21
Serial Control Direction 2 (SCD2) 8-21
Serial Output Flag 0 (OF0) 8-21
Serial Output Flag 1 (OF1) 8-21
Shift Directions (SHFD) 8-20
Synchronous/Asynchronous (SYN) 8-20
Transmit 0 Enable (TE0) 8-19
Transmit 1 Enable (TE1) 8-19
Transmit 2 Enable (TE2) 8-19
Transmit Exception Interrupt Enable (TEIE) 8-18
Transmit Interrupt Enable (TIE) 8-18
Transmit Last Slot Interrupt Enable (TLIE) 8-18
Core Priority (CP) bits 4-5
Core-DMA Priority (CDP) bits 4-12
cross-correlation filtering 11-1
Crystal Disable (XTLD) bit 5-6
crystal frequency 9-6
D
data and control host processor registers 7-12
Data Arithmetic Logic Unit (Data ALU) 1-6
Multiplier-Accumulator (MAC) 1-6
registers 1-6
Data Input (DI) bit 10-25
data memory expansion 1-5
Data Output (DO) bit 10-25
data strobe 7-3
data transfer methods 6-2
interrupts 6-2
polling 6-2
data/coefficient transfer contention bit 11-2
DE signal 2-16
Debug Event signal (DE signal) 2-16
Debug mode
entering 2-16
external indication 2-16
warning 3-6
Debug support 1-4
decimation 11-4, 11-35, 11-41, 11-42
example (sequence of even real numbers) 11-23
Decimation/Channel Count Register (FDCH) 11-41, 11-42
Filter Channels (FCHL) 11-42
Filter Decimation (FDCM) 11-42
Digital Phase-Lock Loop (DPLL) 5-1
description 5-4
Direct Memory Access (DMA) 7-6, 7-8
DSP56321 Reference Manual, Rev. 1
Index-2
Freescale Semiconductor
Index
EFCOP 11-2
EFCOP restrictions 11-5
Request Source bits 4-22
transfers and host bus 7-8
triggered by timer 10-21
Direction (DIR) bit 10-25
DMA Address Mode (DAM) bit 4-27
DMA Channel Enable (DE) bit 4-22
DMA Channel Priority (DPR) bit 4-24
DMA Continuous Mode Enable (DCON) bit 4-25
DMA Control Registers (DCRs) 4-22
bit definitions 4-22
DMA Address Mode (DAM) 4-27
DMA Channel Enable (DE) 4-22
DMA Channel Priority (DPR) 4-24
DMA Continuous Mode Enable (DCON) 4-25
DMA Destination Space (DDS) 4-27
DMA Interrupt Enable (DIE) 4-23
DMA Request Source (DRS) 4-26
DMA Source Space (DSS) 4-27
DMA Three-Dimensional Mode (D3D) 4-27
DMA Transfer Mode (DTM) 4-23
programming sheet B-19
DMA Destination Space (DDS) bit 4-27
DMA Interrupt Enable (DIE) bit 4-23
DMA Request Source (DRS) bit 4-26
DMA Source Space (DSS) bit 4-27
DMA Three-Dimensional Mode (D3D) bit 4-27
DMA Transfer Mode (DTM) bit 4-23
DO FOREVER (FV) Flag bit 4-6
DO loop 1-8
Do Loop Flag (LF) bit 4-6
Double Host Request (HDRQ) bit 7-8, 7-23
Double-Precision Multiply Mode (DM) bit 4-6
DPLL Clock Control (PCTL) Register
Crystal Disable (XTLD) bit 5-6
DPLL Stop State Control (PSTP) bit 5-6
DPLL Static Control Register (DSCR)
Binary Rate Modulation Order (BRMO) bit 5-8
Multiplication Factor Denominator (MFD) bits 5-9
Multiplication Factor Integer (MFI) bits 5-10
Multiplication Factor Numerator (MFN) bits 5-9
Phase Lock Mode (PLM) bit 5-8
Pre-Division Factor (PDF) bits 5-8
DPLL Stop State Control (PSTP) bit 5-6
DRAM Control Register (DCR) 4-18
DSP core
programming model 7-12
DSP56300 core 1-1
DSP56300 Family Manual 1-1, 7-8
DSP56L307 Technical Data 1-1
DSP-to-host
data word 7-2
handshaking protocols 7-2
interrupts 7-2
mapping 7-2
transfer modes 7-2
transfers 7-4, 7-19
dynamic memory configuration switching 3-5
E
echo cancellation 11-1
EFCOP ALU Control Register (FACR)
programming sheet B-38
EFCOP Coefficient Base Address (FCBA) register
programming sheet B-38
EFCOP Control Status Register (FCSR)
programming sheet B-37
EFCOP Counter (FCNT)
programming sheet B-37
EFCOP Data Base Address (FDBA) register
programming sheet B-38
EFCOP Decimation Channel (FDCH) Count Register
programming sheet B-38
Enhanced Filter Coprocessor (EFCOP) 1-2, 1-14, 11-1
control and status registers 11-3
core transfers 11-2
Decimation/Channel Count Register (FDCH) 11-41
Decimation/Channel Counter Register (FDCH) 11-42
Filter Channels (FCHL) 11-42
Filter Decimation (FDCM) 11-42
DMA restrictions 11-4
DMA transfers 11-2
features 11-1
Filter ALU Control Register (FACR) 11-39, 11-40
Filter Input Scale (FISL) 11-40
Filter Rounding Mode (FRM) 11-40
Filter Saturation Mode (FSM) 11-40
Filter Scaling (FSCL) 11-40
Filter Sixteen-bit Arithmetic Mode (FSA) 11-40
Filter Coefficient Base Address (FCBA) register 11-41
Filter Coefficient Memory (FCM)
bank 11-2
Filter Coefficient Memory (FCM) bank 11-2
Filter Control Status Register (FCSR) 11-37
Filter 11-37
Filter Adaptive Mode (FADP) 11-39
Filter Contention (FCONT) 11-37
Filter Data Input Buffer Empty (FDIBE) 11-37
Filter Data Input Interrupt Enable (FDIIE) 11-38
Filter Data Output Interrupt Enable (FDOIE) 11-38
Filter Enable (FEN) 11-39
Filter Multichannel Mode (FMLC) 11-38
Filter Operation Mode (FOM) 11-39
Filter Processing State Initialization Mode (FPRC)
11-38
Filter Saturation (FSAT) 11-37
Filter Shared Coefficients Mode (FSCO) 11-38
Filter Type (FLT) 11-39
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-3
Index
Filter Update (FUPD) 11-39
Filter Count Register (FCNT) 11-36
Filter Data Base Address (FDBA) register 11-41
Filter Data Input Register (FDIR) 11-35
Filter Data Memory (FDM) 11-2, 11-4
Filter Data Memory (FDM) bank 11-2
Filter Data Output Register (FDOR) 11-35
Filter K-Constant Input Register (FKIR) 11-36
Filter Multiplier Accumulator (FMAC) 11-2
Filter Multiplier and Accumulator (FMAC) 11-5
FIR 11-1
IIR 11-1
initialization 11-1
input data buffer 11-2
interrupt vector table 11-35
memory bank base address pointers 11-2
memory banks 11-4
memory organization 11-4
Peripheral Module Bus (PMB) 11-3
programming model 11-35
Saturation mode 11-5
Sixteen-bit Arithmetic mode 11-5
Enhanced Synchronous Serial Interface (ESSI) 1-5, 1-12,
2-2, 2-12, 8-1
24-bit fractional data 8-14
after reset 8-6
Asynchronous mode 8-3, 8-4, 8-10, 8-19
byte format 8-11
clock generator 8-10, 8-16
Clock Sources 8-3
codec 8-11
control and time slot registers 8-6
control direction of SC2 I/O signal 8-21
Control Register A (CRA)
Alignment Control (ALC) 8-14
Frame Rate Divider Control (DC) 8-15
Prescale Modulus Select (PM) 8-15
Prescaler Range (PSR) 8-15
programming sheet B-25
Select SC1 (SSC1) 8-13
Word Length Control (WL) 8-14
Control Register B (CRB)
Clock Polarity (CKP) 8-20
Clock Source Directions (SCKD) 8-21
Frame Sync Length (FSL) 8-20
Frame Sync Polarity (FSP) 8-20
Frame Sync Relative Timing (FSR) 8-20
Mode Select (MOD) 8-20
programming sheet B-26
Receive Enable (RE) 8-19
Receive Exception Interrupt Enable (REIE) 8-18
Receive Interrupt Enable (RIE) 8-18
Receive Last Slot Interrupt Enable 8-18
Serial Control Direction 0 (SCD0) 8-21
Serial Control Direction 1 (SCD1) 8-21
Serial Control Direction 2 (SCD2) 8-21
Serial Output Flag 0 (OF0) 8-21
Serial Output Flag 1 (OF1) 8-21
Shift Direction (SHFD) 8-20
Synchronous/Asynchronous (SYN) 8-20
Transmit 0 Enable (TE0) 8-19
Transmit 1 Enable (TE1) 8-19
Transmit 2 Enable (TE2) 8-19
Transmit Exception Interrupt Enable (TEIE) 8-18
Transmit Interrupt Enable (TIE) 8-18
Transmit Last Slot Interrupt Enable (TLIE) 8-18
control registers 8-12
data and control signals 8-2
DMA 8-6
exception configuration 8-8
exceptions 8-7
receive last slot interrupt 8-7
transmit data 8-8
transmit data with exception status 8-7
transmit last slot interrupt 8-7
flags 8-12
frame rate divider 8-9
frame sync
generator 8-16
length 8-10
polarity 8-11
selection 8-10
signal 8-7, 8-9, 8-17
word length 8-11
initialization 8-6
initialization example 8-6
internally generated clock and frame sync 8-7
interrupt 8-7
Interrupt Service Routine (ISR) 8-8
interrupt trigger event 8-9
multiple serial device selection 8-4
Network mode 8-2, 8-7, 8-9, 8-19, 8-20
Normal mode 8-2, 8-9, 8-19
On-Demand mode 8-9, 8-14, 8-19
operating mode 8-5, 8-9, 8-20
polling 8-7
Port Control Register (PCR) 8-6, 8-33
Port Control Register C (PCRC) 8-33
Port Control Register D (PCRD) 8-33
Port Data Register (PDR) 8-35
Port Data Register C (PDRC) 8-35
Port Data Register D (PDRD) 8-35
Port Direction Register (PRR) 8-34
Port Direction Register C (PRRC) 8-34
Port Direction Register D (PRRD) 8-34
prescale divider 8-15
programming model 8-12
receive data interrupt request 8-26
Receive Data Register (RX) 8-12, 8-28
Receive Shift Register 8-27
DSP56321 Reference Manual, Rev. 1
Index-4
Freescale Semiconductor
Index
receive shift register clock output 8-3
Receive Slot Mask Register (RSM)
programming sheet B-27
Receive Slot Mask Registers (RSMA and RSMB) 8-12,
8-32
reset 8-6
RX clock 8-10
RX frame sync 8-10
RX frame sync pulses active 8-10
select source of clock signal 8-21
Serial Clock (SCK), ESSI 8-2
Serial Control 0 (SC00 and SC10) 8-3
Serial Control 1 (SC01 and SC11) 8-4
Serial Control 2 (SC02 and SC12) 8-5
Serial Input Flag (IF0) 8-3
Serial Output Flag 0 (OF0) 8-17
Serial Output Flag 0 (OF0) bit 8-3
Serial Output Flag 1 (OF1) 8-17
Serial Receive Data (SRD) 8-2
Serial Transmit Data (STD) 8-2
SPI protocol 8-2
Synchronous mode 8-3, 8-4, 8-10, 8-12
Synchronous Serial Interface Status Register (SSISR)
8-12, 8-26
bit definitions 8-26
Receive Data Register Full (RDF) 8-26
Receiver Frame Sync Flag (RFS) 8-27
Receiver Overrun Error Flag (ROE) 8-26
Serial Input Flag 0 (IF0) 8-27
Serial Input Flag 1 (IF1) 8-27
Transmit Data Register Empty (TDE) 8-26
Transmit Frame Sync Flag (TFS) 8-27
Transmitter Underrun Error Flag (TUE) 8-26
Synchronous/Asynchronous (SYN) bit 8-10
Time Slot Register (TSR) 8-8, 8-31
Transmit Data Registers (TX0–TX2) 8-12, 8-31
Transmit Enable (TE) 8-17
Transmit Shift Registers 8-28
Transmit Slot Mask Register (TSM)
programming sheet B-27
Transmit Slot Mask Registers (TSMA and TSMB)
8-12, 8-31
TX clock 8-10
variable prescaler 8-15
word length frame sync 8-11
word length frame sync timing 8-11
Enhanced Synchronous Serial Interface 0 (ESSI0)
GPIO 6-7
Enhanced Synchronous Serial Interface 1 (ESSI1)
GPIO 6-7
EOM byte 4-9
equalization 11-1
ESSI0 Interrupt Priority Level (S0L) bits 4-14
ESSI1 Interrupt Priority Level (S1L) bits 4-14
expansion memory 3-1
Extended Mode Register (EMR) 4-5
Arithmetic Saturation Mode (SM) 4-5
Cache Enable (CE) 4-6
Core Priority (CP) 4-5
DO FOREVER (FV) Flag 4-6
Rounding Mode (RM) 4-5
Sixteen-Bit Arithmetic Mode (SA) 4-6
Extension (E) bit 4-8
external address bus 2-4
external bus control 2-4, 2-5, 2-6
External Bus Disable (EBD) bit 4-12
external data bus 2-4
external memory expansion port 2-4
external Y I/O space 3-4
F
filter
cross-correlation 11-1
FIR 11-1
IIR 11-1
Filter Adaptive Mode (FADP) bit 11-39
Filter ALU Control Register (FACR) 11-39, 11-40
Filter Input Scale (FISL) 11-40
Filter Rounding Mode (FRM) 11-40
Filter Saturation Mode (FSM) 11-40
Filter Scaling (FSCL) 11-40
Filter Sixteen-bit Arithmetic Mode (FSA) 11-40
Filter Channels (FCHL) bits 11-42
Filter Coefficient Base Address (FCBA) register 11-41
Filter Coefficient Memory (FCM) 11-2
Filter Coefficient Memory (FCM) bank 11-2
Filter Contention (FCONT) bit 11-37
Filter Control Status Register (FCSR) 11-37
Filter Adaptive Mode (FADP) 11-39
Filter Contention (FCONT) 11-37
Filter Data Input Buffer Empty (FDIBE) 11-37
Filter Data Input Interrupt Enable (FDIIE) 11-38
Filter Data Output Buffer Full (FDOBF) 11-37
Filter Data Output Interrupt Enable (FDOIE) 11-38
Filter Enable (FEN) 11-39
Filter Multichannel Mode (FMLC) 11-38
Filter Operation Mode (FOM) 11-39
Filter Processing State Initialization Mode (FPRC)
11-38
Filter Saturation (FSAT) 11-37
Filter Shared Coefficients Mode (FSCO) 11-38
Filter Type (FLT) 11-39
Filter Update (FUPD) 11-39
Filter Count Register (FCNT) 11-36
Filter Data Base Address (FDBA) register 11-41
Filter Data Input Buffer Empty (FDIBE) bit 11-37
Filter Data Input Interrupt Enable (FDIIE) bit 11-38
Filter Data Input Register (FDIR) 11-35
Filter Data Memory (FDM)
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-5
Index
bank 11-2
Filter Data Memory (FDM) bank 11-2
Filter Data Output Buffer Full (FDOBF) bit 11-37
Filter Data Output Interrupt Enable (FDOIE) bit 11-38
Filter Data Output Register (FDOR) 11-35
Filter Decimation (FDCM) bits 11-42
Filter Enable (FEN) bit 11-39
Filter Input Scale (FISL) bit 11-40
Filter K-Constant Input Register (FKIR) 11-36
Filter Multichannel Mode (FMLC) bit 11-38
Filter Multiplier Accumulator (FMAC) 11-2
Filter Operation Mode (FOM) bits 11-39
Filter Processing State Initialization Mode (FPRC) bit 11-38
Filter Rounding Mode (FRM) bit 11-40
Filter Saturation (FSAT) bit 11-37
Filter Saturation Mode (FSM) bit 11-40
Filter Scaling (FSCL) bits 11-40
Filter Shared Coefficients Mode (FSCO) bit 11-38
Filter Sixteen-bit Arithmetic Mode (FSA) bit 11-40
Filter Type (FLT) bit 11-39
Filter Update (FUPD) bit 11-39
Finite Impulse Response (FIR) filter 11-1, 11-14, 11-17,
11-23, 11-24, 11-26, 11-27
frame rate divider 8-9
Frame Rate Divider Control (DC) bits 8-15
frame sync
generator 8-16
length 8-10
selection 8-10
signal 8-7, 8-9, 8-17
Frame Sync Length (FSL) bits 8-20
Frame Sync Polarity (FSP) bit 8-20
Frame Sync Relative Timing (FSR) bit 8-20
Framing Error Flag (FE) bit 9-15
G
general-purpose flags for host-DSP communication 7-6
General-Purpose Input/Output (GPIO) 1-5, 2-2, 6-6
ESSI0 6-7
ESSI1 6-7
functionality 1-12
functions 7-4
HI08 6-6
Host Data Direction Register (HDDR) 7-12, 7-31
Host Data Register (HDR) 7-12, 7-31
Port C 6-7
Port D 6-7
Port E 6-7
timer 2-2
Global Data Bus (GDB) 1-10
Ground 2-3
H
HACK signal 7-18
handshaking mechanisms
HI08 7-4
hardware stack 1-8
HI08
Host Port Control Register (HPCR) B-4
HI08 Interrupt Priority Level (HPL) bits 4-14
Host Acknowledge Enable (HAEN) bit 7-18
Host Acknowledge Polarity (HAP) bit 7-16
Host Address Line 8 Enable (HA8EN) 7-18
Host Address Line 9 Enable (HA9EN) 7-18, 8-19
Host Address Strobe Polarity (HASP) bit 7-17
Host Base Address Register (HBAR) 7-12, 7-31
programming sheet B-21
Host Chip Select Enable (HCSEN) bit 7-18
Host Chip Select Polarity (HSCP) bit 7-17
Host Command (HC) bit 7-25
Host Command Interrupt Enable (HCIE) bit 7-13
Host Command Pending (HCP) bit 7-14
Host Control Register (HCR) 7-12, 7-29
Host Command Interrupt Enable (HCIE) 7-13
Host Flag 2 (HF2) 7-13
Host Flag 3 (HF3) 7-13
Host Receive Interrupt Enable (HRIE) 7-13
Host Transmit Interrupt Enable (HTIE) 7-13
programming sheet B-22
Host Data Direction Register (HDDR) 7-4, 7-12,
7-14,
7-31
programming sheet B-33
Host Data Register (HDR) 7-12, 7-15, 7-31
programming sheet B-33
Host Data Strobe Polarity (HDSP) bit 7-17
Host Dual Data Strobe (HDDS) bit 7-17
Host Enable (HEN) bit 7-17
Host Flag 0 (HF0) bit 7-14, 7-23
Host Flag 1 (HF1) bit 7-14, 7-23
Host Flag 2 (HF2) bit 7-13, 7-26
Host Flag 3 (HF3) bit 7-13, 7-26
Host GPIO Port Enable (HGEN) bit 7-18
Host Interface (HI08) 1-5, 1-12, 2-2, 2-8, 2-9, 2-10, 6-2,
7-1
chip-select logic 7-16
Command Vector Register (CVR) 7-8, 7-21
Host Command (HC) 7-25
Host Vector (HV) 7-25
programming sheet B-23
configuring host request mode 7-8
control operating mode 7-16
core communication with HI08 registers 7-12
core interrupts
host command 7-7
receive data register full 7-7
transmit data empty 7-7
data registers 7-21
data strobe 7-3
Direct Memory Access (DMA) 7-8
DSP56321 Reference Manual, Rev. 1
Index-6
Freescale Semiconductor
Index
DMA transfers and host bus 7-8
double-buffered mechanism 7-4
DSP core 7-4
DSP core interrupts 7-7
DSP interrupt routines 7-21
DSP56300 core
programming model 7-12
DSP-side
control registers 7-12
data registers 7-12
registers after reset 7-20
DSP-to-host
data word 7-2
handshaking protocols 7-2
interrupts 7-2
mapping 7-2
transfer modes 7-2
transfers 7-4, 7-19
dual host request enabled 7-9
dual-strobe mode 7-19
enabling host requests 7-8
external host address inputs 7-28
external host programmer’s model 7-20
four kinds of reset 7-28
four reset types 7-20
general-purpose flags for host-DSP communication 7-6
GPIO 6-6
GPIO configuration options 7-14
GPIO functions 7-4
HACK signal 7-18
HACK/HRRQ handshake flags 7-21
handshaking mechanisms 7-4
handshaking protocols 7-4
choosing 7-6
Core DMA access 7-6
host request 7-6
interrupts 7-6
pros and cons of polling 7-6
software polling 7-6
hardware reset 7-20, 7-28
HI08-to-DSP core interface 7-1
HI08-to-host interface 7-1
Host Base Address Register (HBAR) 7-12, 7-15, 7-31
programming sheet B-21
host command 7-7, 7-21
Host Control Register (HCR) 7-12, 7-29
Host Command Interrupt Enable (HCIE) 7-13
Host Flag 2 (HF2) 7-13
Host Flag 3 (HF3) 7-13
Host Receive Interrupt Enable (HRIE) 7-13
Host Transmit Interrupt Enable (HTIE) 7-13
programming sheet B-22
Host Data Direction Register (HDDR) 7-4, 7-12, 7-14,
7-31
programming sheet B-33
Host Data Register (HDR) 7-12, 7-15, 7-31
programming sheet B-33
host interrupt request pins (IRQx) 7-8
Host Port Control Register (HPCR) 7-4, 7-12, 7-16,
7-20, 7-30
Host Acknowledge Enable (HAEN) 7-18
Host Acknowledge Polarity (HAP) 7-16
Host Address Line 8 Enable (HA8EN) 7-18
Host Address Line 9 Enable (HA9EN) 7-18, 8-19
Host Address Strobe Polarity (HASP) 7-17
Host Chip Select Enable (HCSEN) 7-18
Host Chip Select Polarity (HCSP) 7-17
Host Data Strobe Polarity (HDSP) 7-17
Host Dual Data Strobe (HDDS) 7-17
Host Enable (HEN) 7-17
Host GPIO Port Enable (HGEN) 7-18
Host Multiplexed Bus (HMUX) 7-17
Host Request Enable (HREN) 7-18
Host Request Open Drain (HROD) 7-17
Host Request Polarity (HRP) 7-16
programming sheet B-21
host processor registers 7-12
Host Receive (HRX) register 7-4, 7-19, 7-31
Host Receive Request (HRRQ) 7-8
host request line 7-3
host request pins 7-9
host side
Command Vector Register (CVR) 7-24
Interface Control Register (ICR) 7-22
Interface Status Register (ISR) 7-25
Interface Vector Register (IVR) 7-27
Receive Byte Registers (RXH, RXM, RXL) 7-27
register map 7-22
Transmit Byte Registers (TXH, TXM, TXL) 7-28
host side registers after reset 7-28
Host Status Register (HSR) 7-12, 7-13, 7-14, 7-31
Host Command Pending (HCP) 7-14
Host Flag 0 (HF0) 7-14
Host Flag 1 (HF1) 7-14
Host Receive Data Full (HRDF) 7-14
Host Transmit Data Empty (HTDE) 7-14
Host Transmit (HTX) register 7-6, 7-19, 7-27, 7-31
programming sheet B-20, B-24
host-to-DSP
data transfers 7-4, 7-19
data word 7-1
handshaking protocols 7-1
instructions 7-1
mapping 7-1
HREQ/HTRQ handshake flags 7-21
instructions and addressing modes. 7-4
Interface Control Register (ICR) 7-21, 7-22
Double Host Request (HDRQ) 7-8, 7-23
Host Flag 0 (HF0) 7-23
Host Flag 1 (HF1) 7-23
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-7
Index
Host Little Endian (HLEND) 7-23
Initialize (INIT) 7-23
Receive Request Enable (RREQ) 7-24
Transmit Request Enable (TREQ) 7-24
Interface Status Register (ISR) 7-21
Host Flag 2 (HF2) 7-26
Host Flag 3 (HF3) 7-26
Host Request (HREQ) 7-26
Receive Data Full (RDF) 7-6
Receive Data Register Full (RXDF) 7-27
Transmit Data Empty (TDE) 7-6
Transmit Data Register Empty (TXDE) 7-26
Transmitter Ready (TRDY) 7-26
Interrupt Control Register (ICR)
programming sheet B-23
interrupt routines 7-7
Interrupt Vector Register (IVR) 7-21, 7-27
programming sheet B-24
interrupt-based techniques 7-20
masking interrupts 7-7
MOVEP instruction 7-12
multiplexed bus mode 7-3, 7-15, 7-18
non-multiplexed bus mode 7-3, 7-18
pipeline 7-4
polling techniques 7-20, 7-27
programming model
DSP side 7-12
host side 7-20
quick reference 7-29
Receive Byte Registers (RXH, RXM, RXL) 7-4, 7-6,
7-27
register banks 7-4
request service from host 7-8
resets
hardware and software 7-4, 7-12
single-strobe mode 7-19
software polling 7-6
software reset 7-28
STOP instruction 7-21, 7-28
Stop mode 7-21
timing requirements 7-6
Transmit Byte Registers (TXH, TXM, TXL) 7-4, 7-6,
7-28
vector registers 7-21
Host Little Endian (HLEND) bit 7-23
Host Multiplexed Bus (HMUX) bit 7-17
Host Port Control Register (HPCR) 7-4, 7-12, 7-16, 7-20,
7-30, B-4
Host Acknowledge Enable (HAEN) 7-18
Host Acknowledge Polarity (HAP) 7-16
Host Address Line 8 Enable (HA8EN) 7-18
Host Address Line 9 Enable (HA9EN) 7-18, 8-19
Host Address Strobe Polarity (HASP) 7-17
Host Chip Select Enable (HCSEN) 7-18
Host Chip Select Polarity (HCSP) 7-17
Host Data Strobe Polarity (HDSP) 7-17
Host Dual Data Strobe (HDDS) 7-17
Host Enable (HEN) 7-17
Host GPIO Port Enable (HGEN) 7-18
Host Multiplexed Bus (HMUX) 7-17
Host Request Enable (HREN) 7-18
Host Request Open Drain (HROD) 7-17
Host Request Polarity (HRP) 7-16
programming sheet B-21
host processor address space 7-21
Host Receive (HRX) register 7-4, 7-12, 7-19, 7-31
Host Receive Data Full (HRDF) bit 7-6, 7-14
Host Receive Interrupt Enable (HRIE) bit 7-13
Host Receive Request (HRRQ) 7-8
Host Request 7-6
Double 2-2
enabling 7-8
line 7-3
pins 7-9
Single 2-2
Host Request (HREQ) bit 7-26
Host Request Enable (HREN) bit 7-18
Host Request Open Drain (HROD) bit 7-17
Host Request Polarity (HRP) bit 7-16
Host Status Register (HSR) 7-12, 7-13, 7-14, 7-31
Host Command Pending (HCP) 7-14
Host Flag 0 (HF0) 7-14
Host Flag 1 (HF1) 7-14
Host Receive Data Full (HRDF) 7-14
Host Transmit Data Empty (HTDE) 7-14
Host Transmit (HTX) register 7-6, 7-12, 7-19, 7-31
programming sheet B-20, B-24
Host Transmit Data Empty (HTDE) bit 7-6, 7-14
Host Transmit Interrupt Enable (HTIE) bit 7-13
Host Vector (HV) bits 7-25
host-to-DSP transfers 7-4
I
I/O space
external Y data Memory 3-4
X data Memory 3-3
Y data Memory 3-4
Idle Line Flag (IDLE) bit 9-15
Idle Line Interrupt Enable (ILIE) bit 9-12
Idle Line Wakeup mode 9-3
Infinite Impulse Response (IIR) filter 11-1
initialization
EFCOP 11-1
Initialize (INIT) bit 7-23
initializing the timer 10-3
instruction cache 1-4, 3-1
Interface Control Register (ICR) 7-22
Double Host Request (HDRQ) 7-8, 7-23
Host Flag 0 (HF0) 7-23
DSP56321 Reference Manual, Rev. 1
Index-8
Freescale Semiconductor
Index
Host Flag 1 (HF1) 7-23
Host Little Endian (HLEND) 7-23
Initialize (INIT) 7-23
Receive Request Enable (RREQ) 7-24
Transmit Request Enable (TREQ) 7-24
Interface Status Register (ISR) 7-25
Host Flag 2 (HF2) 7-26
Host Flag 3 (HF3) 7-26
Host Request (HREQ) 7-26
Receive Data Full (RDF) 7-6
Receive Data Register Full (RXDF) 7-27
Transmit Data Empty (TDE) 7-6
Transmit Data Register Empty (TXDE) 7-26
Transmitter Ready (TRDY) 7-26
Interface Vector Register (IVR) 7-27
internal buses 1-10
internal program memory 3-1
internal X data Memory 3-2
internal X I/O space 3-3
internal Y data Memory 3-3
Internal Y I/O space 3-4
interrupt 1-8
configuring 4-13
Host Interface (HI08) 7-6, 7-7
source priorities 4-16
sources 4-13, 4-14
table 4-13
table, memory map 4-14
trigger mode 4-14
vector 4-14
interrupt and mode control 2-7
interrupt conditions 6-2
interrupt control 2-7
Interrupt Control Register (ICR)
programming sheet B-23
Interrupt Mask (I) bits 4-8
Interrupt Priority Register Core (IPRC) 4-13
IRQD–IRQA Priority and Mode (IDL–IAL) 4-13
programming sheet B-13
Interrupt Priority Register Peripherals (IPRP) 4-13, 4-14
ESSI0 Interrupt Priority Level (S0L) 4-14
ESSI1 Interrupt Priority Level (S1L) 4-14
HI08 Interrupt Priority Level (HPL) 4-14
programming sheet B-14
SCI Interrupt Priority Level (SCL) 4-14
Timer Interrupt Priority Level (TOL) 4-14
interrupt routines
Host Interface (HI08) 7-7
Interrupt Service Routine (ISR) 8-8, 10-4
interrupt trigger event 8-9
Interrupt Vector Register (IVR) 7-21
programming sheet B-24
interrupts 6-2
Inverter (INV) bit 10-26, 10-28
IRQD–IRQA Priority and Mode (IDL–IAL) bits 4-13
J
Joint Test Action Group (JTAG) 1-8
BSR 4-28
interface 2-15
JTAG 1-4
L
Limit (L) bit 4-8
Loop Address (LA) register 1-8
Loop Counter (LC) register 1-8
Low-Power Divider (LPD) 5-6
M
M68HC11 SCI interface 9-14
Manual Conventions 1-3
mapping control registers 6-1
MC68000 family 7-27
MC68681 DUART 9-14
memory
allocation switching 3-2
configuration 3-5
dynamic switching 3-5
expansion 1-10, 3-1
external expansion port 1-10
maps 3-6
off-chip 1-10
on-chip 1-9
shared 11-2
memory expansion port 1-4
memory maps 3-6, 3-7, 3-8, 3-9, 3-10, 3-11, 3-12,
3-13, 3-14, 3-15, 3-16, 3-17, 3-18, 3-19, 3-20, 3-21,
3-22, 3-23, 3-24, 3-25, 3-26, 3-27, 3-28, 3-29, 3-30,
3-31, 3-32, 3-33, 3-34, 3-35, 3-36, 3-37, 3-38
Memory Switch mode 3-2
X data Memory 3-3
Y data Memory 3-4
Memory Switch Mode (MS) bit 4-12
mobile switching center 11-1
MODD, MODC, MODB, and MODA 9-7
mode control 2-7
Mode Register (MR) 4-5
Do Loop Flag (LF) 4-6
Double-Precision Multiply Mode (DM) 4-6
Interrupt Mask (I) 4-8
Scaling (S) Mode 4-7
Sixteen-Bit Compatibility (SC) mode 4-7
Mode Select (MOD) bit 8-20
modulo adder 1-7
move instruction
MOVE 6-1
MOVEP 6-1, 7-12
Multidrop mode 9-2
multiplexed bus 2-2
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-9
Index
multiplexed bus mode 7-3, 7-15, 7-18
Multiplication Factor Denominator (MFD) bits 5-9
Multiplication Factor Integer (MFI) bits 5-10
Multiplication Factor Numerator (MFN) bits 5-9
Multiplier-Accumulator (MAC) 1-6
N
Negative (N) bit 4-8
Network mode 8-7
non-multiplexed bus 2-2
non-multiplexed bus mode 7-3
O
off-chip memory 1-4
off-chip memory expansion 3-1
offset adder 1-7
OnCE module 1-4
On-Chip Emulation (OnCE) Interface
Debug Event signal (DE signal) 2-16
On-Chip Emulation (OnCE) module 1-9
interface 2-15
On-Chip Emulation module 1-4
on-chip memory 1-4, 1-9
On-Demand mode 8-9, 8-14
Operating 4-1
operating mode 4-1, 4-2
Host Interface (HI08) 7-16
Operating Mode Register (OMR) 1-8, 4-9
Address Attribute Priority Disable (APD) 4-11
Address Trace Enable (ATE) 4-10
Asynchronous Bus Arbitration Enable (ABE) 4-11
Bus Release Timing (BRT) 4-11
Cache Burst Mode Enable (BE) 4-11
Chip Operating Mode (MD–MA) 4-12
COM byte 4-9
Core-DMA Priority (CDP) 4-12
EOM byte 4-9
External Bus Disable (EBD) 4-12
Memory Switch Mode (MS) 4-12
programming sheet B-12
SCS byte 4-9
Stack Extension Enable (SEN) 4-10
Stack Extension Overflow Flag (EOV) 4-10
Stack Extension Underflow Flag (EUN) 4-10
Stack Extension Wrap Flag (WRP) 4-10
Stack Extension XY Select (XYS) 4-10
Stop Delay Mode (SD) 4-12
TA Synchronize Select (TAS) 4-11
Overflow (V) bit 4-9
Overrun Error Flag (OR) bit 9-15
P
Parity Error (PE) bit 9-15
Peripheral I/O Expansion Bus 1-10
Peripheral Module Bus (PMB) 11-3
peripherals programming
bit-oriented instructions 6-1
data transfer methods 6-2
individual reset state 6-1
initialization steps 6-1
interrupts 6-2
mapping control registers 6-1
move (MOVE, MOVEP) instructions 6-1
polling 6-2
reading status registers 6-2
peripherals programming, guidelines 6-1
Phase Lock Loop (PLL) 2-4
Phase Lock Mode (PLM) bit 5-8
PLL Control (PCTL) register
programming sheet B-15, B-16
pointers
EFCOP memory bank base address 11-2
polling 6-2
Port A 2-4, 4-18
Port B 2-2, 6-6
HI08 6-6
programming sheet B-33
Port C 2-12, 6-7
control registers 8-33
Port C Control Register (PCRC) 8-33
programming sheet B-34
Port C Data Register (PDRC) 8-35
programming sheet B-34
Port C Direction Register (PRRC) 8-34
programming sheet B-34
Port D 2-12, 6-7
control registers 8-33
Port D Control Register (PCRD) 8-33
programming sheet B-35
Port D Data Register (PDRD) 8-35
programming sheet B-35
Port D Direction Register (PRRD) 8-34
programming sheet B-35
Port E 6-7
Port E Control Register (PCRE) 9-22
programming sheet B-36
Port E Data Register (PDRE) 9-23
programming sheet B-36
Port E Direction Register (PRRE) 9-22
programming sheet B-36
position independent code 1-7
power management 1-5
Pre-Division Factor (PDF) bits 5-8
prescale divider for ESSI 8-15
Prescale Modulus Select (PM) bits 8-15
Prescaler Clock Enable (PCE) bit 10-25
prescaler counter 10-21
Prescaler Counter Value (PC) bits 10-24
DSP56321 Reference Manual, Rev. 1
Index-10
Freescale Semiconductor
Index
Prescaler Preload Value (PL) bits 10-23
Prescaler Range (PSR) bit 8-15
Prescaler Source (PS) bits 10-23
Program Address Bus (PAB) 1-10
Program Address Generator (PAG) 1-7
Program Control Unit (PCU) 1-7
Program Counter (PC) register 1-8
Program Data Bus (PDB) 1-10
Program Decode Controller (PDC) 1-7
Program Interrupt Controller (PIC) 1-7
program memory expansion 1-5
Program Memory Expansion Bus 1-10
Program RAM 3-1
program RAM 1-4
Program ROM
bootstrap 3-1
programming model
DSP core 7-12
EFCOP 11-35
ESSI 8-12
HI08 7-12
DSP side 7-12
host side 7-20
HI08 quick reference 7-29
SCI 9-8
timer 10-21
RESET 2-7
reset
bus signals 2-4, 2-5
clock signals 2-4
interrupt signals 2-7
JTAG signals 2-16
mode control 2-7
OnCE signals 2-16
PLL signals 2-4
resets
hardware and software 7-4
reverse-carry adder 1-7
ROM
bootstrap 3-1, 3-2
ROM, bootstrap 1-4
Rounding Mode (RM) bit 4-5
RX clock 8-10
S
R
RAM
Program 3-1
reading status registers 6-2
Receive Byte Registers (RXH, RXM, RXL) 7-4, 7-27
Receive Clock Mode Source (RCM) 9-17
Receive Data (RXD) signal 9-4
Receive Data Full (RDF) bit 7-6
Receive Data Register (RX) 8-28
Receive Data Register Full (RDF) bit 8-26
Receive Data Register Full (RDRF) bit 9-15
Receive Data Register Full (RXDF) bit 7-27
Receive Enable (RE) bit 8-19
Receive Exception Interrupt Enable (REIE) bit 8-18
Receive Frame Sync Flag (RFS) 8-27
Receive Interrupt Enable (RIE) bit 8-18
Receive Last Slot Interrupt Enable (RLIE) bit 8-18
Receive Request Enable (RREQ) bit 7-24
Receive Shift Register 8-27
Receive Slot Mask Registers (RSMA and RSMB) 8-12,
8-32
Receive with Exception Interrupt Enable (REIE) bit 9-11
Received Bit 8 (R8) bit 9-15
Receiver Enable (RE) bit 9-13
Receiver Overrun Error Flag (ROE) 8-26
Receiver Wakeup Enable (RWU) bit 9-13
register banks 7-4
saturation status bit 11-2
Scaling (S) bit 4-8
Scaling (S) Mode bits 4-7
SCI 2-14
SCI Clock Control Register (SCCR) 9-8, 9-16
bit definitions 9-17
Clock Divider (CD) 9-17
Clock Out Divider (COD) 9-17
Clock Prescaler (SCP) 9-17
programming sheet B-29
Receive Clock Mode Source (RCM) 9-17
Transmit Clock Source (TCM) 9-17
SCI Clock Polarity (SCKP) bit 9-11
SCI Control Register (SCR) 9-8, 9-11
bit definitions 9-11
Idle Line Interrupt Enable (ILIE) 9-12
programming sheet B-28
Receive with Exception Interrupt Enable (REIE) 9-11
Receiver Enable (RE) 9-13
Receiver Wakeup Enable (RWU) 9-13
SCI Clock Polarity (SCKP) 9-11
SCI Receive Interrupt Enable (RIE) 9-12
SCI Shift Direction (SSFTD) 9-14
SCI Transmit Interrupt Enable (TIE) 9-12
Send Break (SBK) 9-13
Timer Interrupt Enable (TMIE) 9-11
Timer Interrupt Rate (STIR) 9-11
Transmitter Enable (TE) 9-12
Wakeup Mode Select (WAKE) 9-13
Wired-OR Mode Select (WOMS) 9-13
Word Select (WDS) 9-14
SCI Interrupt Priority Level (SCL) bits 4-14
SCI Receive Data Register (SRX) 9-8, 9-20
SCI Receive Interrupt Enable (RIE) bit 9-12
SCI Serial Clock signal (SCLK) 9-4
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-11
Index
SCI Shift Direction (SSFTD) 9-14
SCI Status Register (SSR) 9-8, 9-14
bit definitions 9-15
Framing Error Flag (FE) 9-15
Idle Line Flag (IDLE) 9-15
Overrun Error Flag (OR) 9-15
Parity Error (PE) 9-15
Receive Data Register Full (RDRF) 9-15
Received Bit 8 (R8) 9-15
Transmit Data Register Empty (TDRE) 9-16
Transmitter Empty (TRNE) 9-16
SCI Transmit Data Address Register (STXA) 9-9
SCI Transmit Data Register (STX or STXA) 9-19
SCI Transmit Data Register (STX) 9-9, 9-21
SCI Transmit Interrupt Enable (TIE) bit 9-12
SCLK 9-2, 9-6
SCS byte 4-9
Select SC1 (SSC1) bit 8-13
Send Break (SBK) bit 9-13
Serial Clock (SCK) 8-2
Serial Clock (SCLK), SCI 9-2
Serial Communication Interface (SCI) 1-5
Serial Communications Interface (SCI) 1-13, 2-2, 2-14,
6-2, 9-1
Address Mode Wakeup 9-3
Asynchronous mode 9-2
bootstrap loading 9-7
crystal frequency 9-6
data registers 9-19
Data Word Formats 9-9
enable wakeup function 9-13
enable/disable SCI receive data with exception interrupt
9-11
exceptions 9-8
Idle Line 9-8
Receive Data 9-8
Receive Data with Exception Status 9-8
Timer 9-8
Transmit Data 9-8
General-Purpose Input/Output (GPIO)
SCI 6-7
GPIO functionality 9-22
I/O signals 9-3
Idle Line Wakeup mode 9-3
individual reset state (PCR = $0) 9-6
initialization 9-6
Inter-processor messages 9-2
interrupts 9-6
Multidrop mode 9-2
operating mode 9-1
Asynchronous 9-1
Synchronous 9-1
programming model 9-8
data registers 9-20
Receive Data (RXD) 9-4
recover synchronization 9-2
reset 9-4
SCI Clock Control Register (SCCR) 9-6, 9-7, 9-8,
9-16
bit definitions 9-17
Clock Divider (CD) 9-17
Clock Out Divider (COD) 9-17
Clock Prescaler (SCP) 9-17
programming sheet B-29
Receive Clock Mode Source (RCM) 9-17
Transmit Clock Source (TCM) 9-17
SCI Control Register (SCR) 9-6, 9-7, 9-8, 9-11
bit definitions 9-11
Idle Line Interrupt Enable (ILIE) 9-12
programming sheet B-28
Receive with Exception Interrupt Enable (REIE)
9-11
Receiver Enable (RE) 9-13
Receiver Wakeup Enable (RWU) 9-13
SCI Clock Polarity (SCKP) 9-11
SCI Receive Interrupt Enable (RIE) 9-12
SCI Shift Direction (SSFTD) 9-14
SCI Transmit Interrupt Enable (TIE) 9-12
Send Break (SBK) 9-13
Timer Interrupt Enable (TMIE) 9-11
Timer Interrupt Rate (STIR) 9-11
Transmitter Enable (TE) 9-12
Wakeup Mode Select (WAKE) 9-13
Wired-OR Mode Select (WOMS) 9-13
Word Select (WDS) 9-14
SCI Receive Data Register (SRX) 9-8, 9-20
SCI Status Register (SSR) 9-8, 9-14
bit definitions 9-15
Framing Error Flag (FE) 9-15
Idle Line Flag (IDLE) 9-15
Overrun Error Flag (OR) 9-15
Parity Error (PE) 9-15
Receive Data Register Full (RDRF) 9-15
Received Bit 8 (R8) 9-15
Transmit Data Register Empty (TDRE) 9-16
Transmitter Empty (TRNE) 9-16
SCI Transmit Data Address Register (STXA) 9-9
SCI Transmit Data Register (STX) 9-9
select wakeup on idle line mode 9-13
Serial Clock (SCLK) 9-4, 9-19
state after reset 9-5
Synchronous mode 9-2
transmission priority
preamble, break, and data 9-7
transmit and receive shift registers 9-2
Transmit Data (TXD) 9-4
Transmit Data Register (STX or STXA) 9-19
Transmit Data Register (STX) 9-21
Wired-OR mode 9-3
Serial Control 0 (SC00 and SC10) signals 8-3
DSP56321 Reference Manual, Rev. 1
Index-12
Freescale Semiconductor
Index
Serial Control 1 (SC01 and SC11) signals 8-4
Serial Control 2 (SC02 and SC12) signals 8-5
Serial Control Direction 0 (SCD0) bit 8-21
Serial Control Direction 1 (SCD1) bit 8-21
Serial Control Direction 2 (SCD2) bit 8-21
Serial Input Flag 0 (IF0) bit 8-3, 8-27
Serial Input Flag 1 (IF1) bit 8-27
Serial Output Flag 0 (OF0) bit 8-3, 8-17, 8-21
Serial Output Flag 1 (OF1) bit 8-17, 8-21
Serial Receive Data (SRD) signal 8-2
Serial Transmit Data (STD) signal 8-2
setting timer operating mode 10-3
shared memory 11-2
Shift Direction (SHFD) bit 8-20
signals
functional grouping 2-2
Sixteen-Bit Arithmetic Mode (SA) bit 4-6
Sixteen-Bit Compatibility (SC) mode bit 4-7
Sixteen-bit Compatibility mode 3-6
Size (SZ) register 1-8
software polling 7-6
SRAM
interfacing 1-10
support 1-5
Stack Counter (SC) register 1-8
Stack Extension Enable (SEN) bit 4-10
Stack Extension Overflow Flag (EOV) bit 4-10
Stack Extension Underflow Flag (EUN) bit 4-10
Stack Extension Wrap Flag (WRP) bit 4-10
Stack Extension XY Select (XYS) bit 4-10
Stack Pointer (SP) 1-8
Status Register (SR) 1-8, 4-5
bit definitions 4-5
Condition Code Register (CCR) 4-5
Carry (C) 4-9
Extension (E) 4-8
Limit (L) 4-8
Negative (N) 4-8
Overflow (V) 4-9
Scaling (S) 4-8
Unnormalized (U) 4-8
Zero (Z) 4-9
Extended Mode Register (EMR) 4-5
Arithmetic Saturation Mode (SM) 4-5
Cache Enable (CE) 4-6
Core Priority (CP) 4-5
DO FOREVER (FV) Flag 4-6
Instruction Cache Enable (CE) 4-5
Rounding Mode (RM) 4-5
Sixteen-Bit Arithmetic Mode (SA) 4-6
Mode Register (MR) 4-5
Do Loop Flag (LF) 4-6
Double-Precision Multiply Mode (DM) 4-6
Interrupt Mask (I) 4-8
Scaling (S) Mode 4-7
Sixteen-Bit Compatibility (SC) Mode 4-7
programming sheet B-11
status registers, reading 6-2
Stop Delay Mode (SD) bit 4-12
STOP instruction 7-20, 9-6
Stop mode 1-5
Stop state 5-6
Switch mode 1-4
switching memory configuration dynamically 3-5
switching memory sizes 3-2
Synchronous mode 8-9, 8-10, 8-12, 9-2, 9-16
Synchronous Serial Interface Status Register (SSISR) 8-12,
8-26
Receive Data Register Full (RDF) 8-26
Receiver Frame Sync Flag (RFS) 8-27
Receiver Overrun Error Flag (ROE) 8-26
Serial Input Flag 0 (IF0) 8-27
Serial Input Flag 1 (IF1) 8-27
Transmit Data Register Empty (TDE) 8-26
Transmit Frame Sync Flag (TFS) 8-27
Transmitter Underrun Error Flag (TUE) 8-26
Synchronous/Asynchronous (SYN) bit 8-20
T
TA Synchronize Select (TAS) bit 4-11
target applications 1-5
Test Access Port (TAP) 1-4, 1-8
Time Slot Register (TSR) 8-31
timer 2-15
after Reset 10-3
enabling 10-3
exception 10-4
Compare 10-4
Overflow 10-4
initialization 10-3
module 1-13
timer block diagram 10-2
operating modes 10-5
Capture (mode 6) 10-5, 10-11, 10-15
Event Counter (mode 3) 10-5, 10-10
GPIO (mode 0) 10-5
Input Period (mode 5) 10-5, 10-11, 10-13
Input Width (mode 4) 10-5, 10-11
overview 10-5
Pulse (mode 1) 10-5, 10-7
Pulse Width Modulation (PWM) (mode 7) 10-5,
10-11, 10-16
reserved 10-20
setting 10-3
signal measurement modes 10-11
Toggle (mode 2) 10-5, 10-8
watchdog modes 10-18
Watchdog Pulse (mode 9) 10-5, 10-18
Watchdog Toggle (mode 10) 10-5,
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-13
Index
10-18
prescaler counter 10-21
programming model 10-21
special cases 10-21
timer compare interrupts 10-28
Timer Compare Register (TCPR) 10-30
Timer Control/Status Register (TCSR) 10-24
Data Input (DI) 10-25
Data Output (DO) 10-25
Direction (DIR) 10-25
Inverter (INV) 10-26, 10-28
Prescaler Clock Enable (PCE) 10-25
Timer Compare Flag (TCF) 10-25
Timer Compare Interrupt Enable (TCIE) 10-28
Timer Control (TC) 10-27
Timer Enable (TE) 10-28
Timer Overflow Flag (TOF) 10-25
Timer Overflow Interrupt Enable (TOIE) 10-28
Timer Reload Mode (TRM) 10-26
Timer Count Register (TCR) 10-30
Timer Load Registers (TLR) 10-29
Timer Prescaler Count Register (TPCR) 10-24
Prescaler Counter Value (PC) 10-24
Timer Prescaler Load Register (TPLR) 10-23
bit definitions 10-23
Prescaler Preload Value (PL) 10-23
Prescaler Source (PS) 10-23
Timer Compare Flag (TCF) bit 10-25
Timer Compare Interrupt Enable (TCIE) bit 10-28
Timer Compare Register (TCPR) 10-3, 10-4, 10-30
Timer Control (TC) bits 10-27
Timer Control/Status Register (TCSR) 10-3, 10-24
bit definitions 10-24
Data Input (DI) 10-25
Data Output (DO) 10-25
Direction (DIR) 10-25
Inverter (INV) 10-26, 10-28
Prescaler Clock Enable (PCE) 10-25
programming sheet B-31
Timer Compare Flag (TCF) 10-25
Timer Compare Interrupt Enable (TCIE) 10-28
Timer Control (TC) 10-27
Timer Enable (TE) 10-28
Timer Overflow Flag (TOF) 10-25
Timer Overflow Interrupt Enable (TOIE) 10-28
Timer Reload Mode (TRM) 10-26
Timer Count Register (TCR) 10-30
Timer Enable (TE) bit 10-28
Timer Interrupt Enable (TMIE) bit 9-11
Timer Interrupt Priority Level (TOL) bits 4-14
Timer Interrupt Rate (STIR) bit 9-11
Timer Load Registers (TLR) 10-3, 10-29
programming sheet B-32
Timer module
architecture 10-1
Timer Overflow Flag (TOF) bit 10-25
Timer Overflow Interrupt Enable (TOIE) bit 10-28
Timer Prescaler Count Register (TPCR) 10-24
bit definitions 10-24
Prescaler Counter Value (PC) 10-24
Timer Prescaler Load Register (TPLR) 10-3, 10-23
bit definitions 10-23
Prescaler Preload Value (PL) 10-23
Prescaler Source (PS) 10-23
programming sheet B-30
Timer Reload Mode (TRM) bit 10-26
transcoder basestation 11-1
Transmit 0 Enable (TE0) bit 8-19
Transmit 1 Enable (TE1) bit 8-19
Transmit 2 Enable (TE2) bit 8-19
Transmit Byte Registers (TXH, TXM, TXL) 7-4, 7-28
Transmit Clock Source (TDM) bit 9-17
Transmit Data Empty (TDE) bit 7-6
Transmit Data Register Empty (TDE) bit 8-26
Transmit Data Register Empty (TDRE) bit 9-16
Transmit Data Register Empty (TXDE) bit 7-26
Transmit Data Registers (TX0–TX2) 8-12, 8-31
Transmit Data signal (TXD) 9-4
Transmit Enable (TE) bits 8-17
Transmit Exception Interrupt Enable (TEIE) bit 8-18
Transmit Frame Sync Flag (TFS) 8-27
Transmit Interrupt Enable (TIE) bit 8-18
Transmit Last Slot Interrupt Enable (TLIE) bit 8-18
Transmit Request Enable (TREQ) bit 7-24
Transmit Shift Registers 8-28
Transmit Slot Mask Registers (TSMA and TSMB) 8-12,
8-31
Transmitter Empty (TRNE) bit 9-16
Transmitter Enable (TE) bit 9-12
Transmitter Ready (TRDY) bit 7-26
Transmitter Underrun Error Flag (TUE) 8-26
triple timer 6-2
triple timer module 1-13
TX clock 8-10
TXD signal 9-4
U
Unnormalized (U) bit 4-8
V
Vector Base Address (VBA) register 1-8
vocoder 11-1
W
Wait mode 1-5
Wakeup Mode Select (WAKE) bit 9-13
Wired-OR Mode Select (WOMS) bit 9-13
Word Length Control (WL) bits 8-14
DSP56321 Reference Manual, Rev. 1
Index-14
Freescale Semiconductor
Index
Word Select (WDS) bits 9-14
X
X data Memory
internal 3-2
X data memory 3-2
X I/O space 3-3
internal 3-3
X Memory Address Bus (XAB) 1-10
X Memory Data Bus (XDB) 1-10
X Memory Expansion Bus 1-10
X-data RAM 1-4
Y
Y data Memory 3-3
internal 3-3
Y I/O space 3-4
Y Memory Address Bus (YAB) 1-10
Y Memory Data Bus (YDB) 1-10
Y Memory Expansion Bus 1-10
Y-data RAM 1-4
Z
Zero (Z) bit 4-9
DSP56321 Reference Manual, Rev. 1
Freescale Semiconductor
Index-15
Index
DSP56321 Reference Manual, Rev. 1
Index-16
Freescale Semiconductor