ADSP-21061 EZ-KIT Lite™ Evaluation System

ADSP-21061 EZ-KIT Lite™ Evaluation System

Figure 2-2 Hardware Connections to the ADSP-21061 EZ-KIT Lite

2.6.1. Serial Port (RS-232) Connector

P1 is female 9-pin D-Sub connector used to communicate with a host computer using RS-

232 signal levels and asynchronous serial protocols. The supplied cable provides a straightthrough connection from the DCE port on the EZ-KIT Lite to the DTE port on your PC.

The DCD, DTR, and DSR signals are connected on the EZ-KIT Lite board.

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Table 2-3 Serial Port Pin Descriptions

Pin No.

7

8

9

5

6

3

4

1

2

Signal Name

DCD

Transmit Data (output)

Receive Data (input)

DTR

Signal Ground

DSR

Request to Send (input)

Clear to Send (output)

Not Connected

2.6.2. Stereo Audio Output

The Stereo Audio Output Jack connects to the left (L) and right (R) LINE OUTPUT pins of the AD1847 codec. Use standard audio cables with 1/8 inch (3.5mm) stereo plugs to connect these signals to a set of amplified speakers.

2.6.3. Stereo Audio Input

The Stereo Audio Input jack connects directly to the left (L) and right (R) LINE 1 INPUT pins of the AD1847 codec. Use standard audio cables with 1/8 inch (3.5mm) stereo plugs to supply these inputs with line-level signals. You can also connect a microphone-level signal by changing the Input Source Selector Jumpers. (See section 5.3.1)

2.6.4. DC Power Supply Connector

The power supply connector is used to supply DC voltages to the ADSP-21061 EZ-KIT

Lite board. The DC power supply included with your board mates directly to this connector.

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3. USING THE EZ-KIT LITE SOFTWARE

3.1. Overview

The combination of the EZ-KIT Lite board and the monitor software operate as a target for the

VisualDSP++ IDDE. The IDDE allows you to view the processor registers and memory and perform several debugging activities, such as setting breakpoints, stepping through code, and plotting a range of memory.

If VisualDSP++ is not installed, install it from the VisualDSP++ CD-ROM that came with this product. For more information, refer to Chapter 2, section “VisualDSP++”.

This chapter provides monitor level software information on how the EZ-KIT Lite board operates with the installed software. This chapter also provides information to help you run your own programs on the ADSP-21061 EZ-KIT Lite board. This information appears in the following sections:

• “Standard Operation” – Describes the operation of the EZ-KIT Lite board

• “Running You Own Programs” – Provides information about writing and running your own

DSP executables that link with the monitor program to run on the EZ-KIT Lite board

3.2. Standard Operation

This section covers the standard operation of the EZ-KIT Lite board. It describes the I/O capabilities of the on-board components, board power-up, and the on-board monitor program.

3.2.1. I/O Devices

This section describes the different I/O devices on the ADSP-21061 EZ-KIT Lite. These are flags, external interrupts, and serial ports.

3.2.1.1. Flags

The ADSP-21061 SHARC processor has four I/O flags that you can program as inputs or outputs. Bits in the MODE2 register control the direction. At reset, all of the flags are configured as inputs. Bits in the ASTAT register contain the value of each of the flag pins.

FLAG0 controls the pin on the AD1847 codec. Clearing FLAG0 (=0) holds the AD1847 in reset. Setting FLAG0 (=1) releases RESET and restarts the AD1847. The programmer should configure FLAG0 as an output and set high during program initialization. FLAG0 is also connected to LED D2 on the ADSP-21061 EZ-KIT Lite. LED D2 is lit when FLAG0 is cleared.

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FLAG1 is connected to the pushbutton switch labeled “FLAG1” (S1) and to LED D3. The programmer should configure FLAG1 as an input during program initialization. The DSP’s

FLAG1 input value is “0” (and LED D3 will light) when the pushbutton is depressed and the value is “1” when the pushbutton is released.

FLAG2 is connected to LED D4. The programmer should configure FLAG2 as an output during program initialization. The LED D4 lights while FLAG2 is zero.

FLAG3 is connected to LED D6. The programmer should configure FLAG3 as an output during program initialization. The LED D6 lights while FLAG3 is zero.

Table 3-1 Flag Summary

FLAG

FLAG1

FLAG0, 2, and 3

USE

Pushbutton Input

LED Feedback

3.2.1.2. External Interrupts

The ADSP-21061 SHARC DSP has three external interrupt pins. They are prioritized, individually maskable (IMASK register), and can be configured to be edge sensitive or level sensitive (bits in the MODE2 register). At reset, all external interrupts are levelsensitive and masked. Other relevant ADSP-21061 SHARC DSP registers are MODE1

(NESTM and IRPTEN bits), IRPTL, and IMASKP.

Two of the ADSP-21061 SHARC DSP’s three external interrupt inputs are allocated on the

ADSP-21061 EZ-KIT Lite.

IRQ0 is not connected to any devices on the ADSP-21061 EZ-KIT Lite; however, it is connected to one of the expansion connectors.

IRQ1 is connected to a pushbutton switch on the ADSP-21061 EZ-KIT Lite board.

Pressing the pushbutton generates the interrupt.

IRQ2 is connected to the 16550 UART, which can be programmed to generate an interrupt when it requires attention.

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3.2.1.3. Serial Ports

The ADSP-21061 SHARC processor has two high-speed, synchronous serial ports

(SPORTs). They can operate in point-to-point connection in full-duplex mode with independent transmit and receive data lines and clocks, or they can be wired together with multiple SPORTs to operate in a time division multiplexed (TDM) mode.

SPORT0 is connected to the serial port on the AD1847 SoundPort codec. This port is configured for multi-channel TDM operation.

SPORT1 is not connected to any devices on the ADSP-21061 EZ-KIT Lite; however, it is connected to one of the expansion connectors.

3.2.2. POST Routines

POST (Power On Self-Test) routines are a series of standard tests and initializations that the EZ-KIT Lite performs on a power-on reset.

3.2.2.1. UART Check/Initialization

The UART check is performed in three stages. Two of these stages are implemented in the

POST. The third is controlled by the host (PC), when it attempts to connect to the EZ-KIT

Lite. These stages are:

• Register Write

This test confirms that the ADSP-21061 SHARC processor is capable of writing to (and reading from) a register in the UART. Three patterns are written to and then read from a register in the UART, and tested. All three patterns must be read back correctly to pass this test.

• Internal Loop Back

In this test, 256 bytes are sent to and read from the UART. This test checks the functionality of the UART connections from the ADSP-21061 SHARC processor, up to and through the UART chip.

• Transmitted Loop Back

The last UART test is performed by the host after the POST is complete. In this test, the host sends the UART test protocol. This protocol specifies the number of bytes that are transmitted to the EZ-KIT Lite board, and instructs the board to echo the byte stream back to the host. This test determines whether the EZ-KIT Lite board is set to the correct baud rate and verifies the external connections between the board and the host.

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On power up, the EZ-KIT Lite board defaults to a baud rate of 115200 with 8 data bits, 1 stop bit, and no parity. If you want to change this rate, change it after the POST is complete by using the

Settings -> Baud Rate

command from the menu bar. Note that setting the baud rate to a lower number can significantly slow the board’s response to all debug activities.

3.2.3. Monitor Program Operation

The Monitor runs on the EZ-KIT Lite board as part of the DSP executable, and provides the ability to download, debug, and run user programs. The Monitor uses VisualDSP++ as the interface. Using the EZ-KIT Lite as a target allows you to operate the board remotely.

On initial power-up of the EZ-KIT Lite board, the original monitor is booted from the

EPROM to the target board. Once you start the EZ-KIT Lite debug session using

VisualDSP++, this monitor downloads a new monitor from your PC onto the target board.

The new monitor communicates to the target dll through the serial port.

There are three main components of the new monitor program:

• Halt loop

• UART ISR

• Command Processing Kernel

The monitor program idles in the Halt loop when it is not running user code. While there, you can read/write memory, read/write registers, download programs, set breakpoints, change the UART’s baud rate, and single-step through code.

To enter the halt loop from your code, you must halt user code—either with a breakpoint or a halt instruction. At this point, the halt loop polls the UART. With every character received from the UART, the command-processing kernel verifies whether a full command has been received. If a command has been received, the kernel processes the command; otherwise control is returned to the halt loop to wait for more characters. The only method of executing your code once the halt loop has been entered is to send a Run or Single Step command in the IDDE.

The UART ISR is entered when user code is running, but the host is still interacting with the board. As the host sends bytes, the UART ISR takes the data stream from the UART and builds the command. Similar to the halt loop, each character received is passed to the command-processing kernel. Unlike the halt loop, the monitor returns to the user code immediately after the interrupt is serviced.

Be aware of the following restrictions to ensure correct board operation.

• If the user program disables the UART interrupt or changes the UART interrupt vector the host loses contact with the monitor while the user program is running.

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• When nesting is turned off the host loses contact with the monitor while the program is running and in an ISR.

• The host loses contact with the monitor while the program is running and in the timer

ISR, provided the highest priority timer vector is used.

• The host cannot halt with the IDDE’s Debug, Halt command if global IRQ enable is disabled (IRPTEN bit); however, breakpoints work.

Command processing, initiated from either the UART ISR or the Halt Loop, is done in the command-processing kernel. This kernel parses the commands and executes the instructions. If the instruction requires that data be sent back to the host, the kernel initiates the response.

3.3. Running Your Own Programs

This section provides basic information needed to run your own programs on the ADSP-21061

EZ-KIT Lite board. Build these programs using the ADSP-21061 SHARC processor tools. This information includes rules for using processor memory.

Although there are many ways to develop programs in VisualDSP++, all program evaluation within the environment include the following steps:

1. Create a new project file

2. Set the target processor under “Project Options”

3. Add and edit project source files

4. Customize project build options

5. Build a debug version of the project

6. Debug the project

7. Build a release version of the project

By following these steps, DSP projects build consistently and accurately with minimal project management. The ADSP-2106x SHARC User’s Manual provides detailed information on programming the processor, and the VisualDSP++ manuals provide information on code development with the ADSP-21061 SHARC processor tools.

• Do not run more than one ADSP-21061 EZ-KIT Lite session at any one time. You may run an EZ-KIT Lite debug session and a simulator, or you can run a JTAG ICE session and a simulator session at the same time.

• If you are creating a C/C++ program use the 060_hdr.asm file supplied with the demo programs. This file reserves the IRQ2 interrupt vector table for the UART.

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