PIC16F72 Data Sheet 28-Pin, 8-Bit CMOS FLASH Microcontoller with A/D Converter

PIC16F72 Data Sheet 28-Pin, 8-Bit CMOS FLASH Microcontoller with A/D Converter
PIC16F72
Data Sheet
28-Pin, 8-Bit CMOS FLASH
Microcontoller with A/D Converter
© 2007 Microchip Technology Inc.
DS39597C
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DS39597C-page ii
© 2007 Microchip Technology Inc.
PIC16F72
28-Pin, 8-Bit CMOS FLASH MCU with A/D Converter
• PIC16F72
High Performance RISC CPU:
PDIP, SOIC, SSOP
•1
2
3
4
5
6
7
8
9
10
11
12
13
14
MCLR/VPP
RA0/AN0
RA1/AN1
RA2/AN2
RA3/AN3/VREF
RA4/T0CKI
RA5/AN4/SS
VSS
OSC1/CLKI
OSC2/CLKO
RC0/T1OSO/T1CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
QFN
Peripheral Features:
CMOS Technology:
•
•
•
•
•
Low power, high speed CMOS FLASH technology
Fully static design
Wide operating voltage range: 2.0V to 5.5V
Industrial temperature range
Low power consumption:
- < 0.6 mA typical @ 3V, 4 MHz
- 20 μA typical @ 3V, 32 kHz
- < 1 μA typical standby current
© 2007 Microchip Technology Inc.
RA2/AN2
RA3/AN3/VREF
RA4/T0CKI
RA5/AN4/SS
VSS
OSC1/CLKI
OSC2/CLKO
28
27
26
25
24
23
22
21
20
19
18
17
16
15
RB7/PGD
RB6/PGC
RB5
RB4
RB3
RB2
RB1
RB0/INT
VDD
VSS
RC7
RC6
RC5/SDO
RC4/SDI/SDA
1
2
3
4
5
6
7
28 27 26 25 24 23 22
21
20
19
18
PIC16F72
17
16
15
8 9 10 11 12 13 14
RB3
RB2
RB1
RB0/INT
VDD
VSS
RC7
RC0/T1OSO/T1CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6
• High Sink/Source Current: 25 mA
• Timer0: 8-bit timer/counter with 8-bit prescaler
• Timer1: 16-bit timer/counter with prescaler,
can be incremented during SLEEP via external
crystal/clock
• Timer2: 8-bit timer/counter with 8-bit period
register, prescaler and postscaler
• Capture, Compare, PWM (CCP) module
- Capture is 16-bit, max. resolution is 12.5 ns
- Compare is 16-bit, max. resolution is 200 ns
- PWM max. resolution is 10-bit
• 8-bit, 5-channel analog-to-digital converter
• Synchronous Serial Port (SSP) with
SPI™ (Master/Slave) and I2C™ (Slave)
• Brown-out detection circuitry for
Brown-out Reset (BOR)
PIC16F72
• Only 35 single word instructions to learn
• All single cycle instructions except for program
branches, which are two-cycle
• Operating speed: DC - 20 MHz clock input
DC - 200 ns instruction cycle
• 2K x 14 words of Program Memory,
128 x 8 bytes of Data Memory (RAM)
• Pinout compatible to PIC16C72/72A and
PIC16F872
• Interrupt capability
• Eight-level deep hardware stack
• Direct, Indirect and Relative Addressing modes
Pin Diagrams
RA1/AN1
RA0/AN0
MCLR/VPP
RB7/PGD
RB6/PGC
RB5
RB4
Device Included:
Special Microcontroller Features:
• 1,000 erase/write cycle FLASH program memory
typical
• Power-on Reset (POR), Power-up Timer (PWRT)
and Oscillator Start-up Timer (OST)
• Watchdog Timer (WDT) with its own on-chip
RC oscillator for reliable operation
• Programmable code protection
• Power saving SLEEP mode
• Selectable oscillator options
• In-Circuit Serial Programming™ (ICSP™) via 2 pins
• Processor read access to program memory
DS39597C-page 1
PIC16F72
Key Reference Manual Features
PIC16F72
Operating Frequency
RESETS and (Delays)
FLASH Program Memory - (14-bit words, 1000 E/W cycles)
Data Memory - RAM (8-bit bytes)
Interrupts
I/O Ports
Timers
Capture/Compare/PWM Modules
Serial Communications
8-bit A/D Converter
Instruction Set (No. of Instructions)
DC - 20 MHz
POR, BOR, (PWRT, OST)
2K
128
8
PORTA, PORTB, PORTC
Timer0, Timer1, Timer2
1
SSP
5 channels
35
DS39597C-page 2
© 2007 Microchip Technology Inc.
PIC16F72
Table of Contents
1.0 Device Overview .......................................................................................................................................................................... 5
2.0 Memory Organization ................................................................................................................................................................... 7
3.0 I/O Ports ..................................................................................................................................................................................... 21
4.0 Reading Program Memory ......................................................................................................................................................... 27
5.0 Timer0 Module ........................................................................................................................................................................... 29
6.0 Timer1 Module ........................................................................................................................................................................... 31
7.0 Timer2 Module ........................................................................................................................................................................... 35
8.0 Capture/Compare/PWM (CCP) Module ..................................................................................................................................... 37
9.0 Synchronous Serial Port (SSP) Module ..................................................................................................................................... 43
10.0 Analog-to-Digital Converter (A/D) Module.................................................................................................................................. 53
11.0 Special Features of the CPU...................................................................................................................................................... 59
12.0 Instruction Set Summary ............................................................................................................................................................ 73
13.0 Development Support................................................................................................................................................................. 81
14.0 Electrical Characteristics ............................................................................................................................................................ 87
15.0 DC and AC Characteristics Graphs and Tables....................................................................................................................... 107
16.0 Package Marking Information................................................................................................................................................... 117
Appendix A: Revision History ........................................................................................................................................................ 123
Appendix B: Conversion Considerations........................................................................................................................................ 123
Index .................................................................................................................................................................................................. 125
On-Line Support................................................................................................................................................................................. 131
Reader Response .............................................................................................................................................................................. 132
Product Identification System ............................................................................................................................................................ 133
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© 2007 Microchip Technology Inc.
DS39597C-page 3
PIC16F72
NOTES:
DS39597C-page 4
© 2007 Microchip Technology Inc.
PIC16F72
1.0
DEVICE OVERVIEW
The program memory contains 2K words, which translate to 2048 instructions, since each 14-bit program
memory word is the same width as each device
instruction. The data memory (RAM) contains 128 bytes.
This document contains device specific information for
the operation of the PIC16F72 device. Additional information may be found in the PIC™ Mid-Range MCU
Reference Manual (DS33023), which may be downloaded from the Microchip website. The Reference
Manual should be considered a complementary document to this data sheet, and is highly recommended
reading for a better understanding of the device architecture and operation of the peripheral modules.
There are 22 I/O pins that are user configurable on a
pin-to-pin basis. Some pins are multiplexed with other
device functions. These functions include:
• External interrupt
• Change on PORTB interrupt
• Timer0 clock input
• Timer1 clock/oscillator
• Capture/Compare/PWM
• A/D converter
• SPI/I2C
Table 1-1 details the pinout of the device with
descriptions and details for each pin.
The PIC16F72 belongs to the Mid-Range family of the
PIC devices. A block diagram of the device is shown in
Figure 1-1.
FIGURE 1-1:
PIC16F72 BLOCK DIAGRAM
13
FLASH
Program
Memory
2K x 14
Program
Bus
PORTA
RA0/AN0
RA1/AN1
RA2/AN2
RA3/AN3/VREF
RA4/T0CKI
RA5/AN4/SS
RAM
File
Registers
128 x 8
8-Level Stack
(13-bit)
14
8
Data Bus
Program Counter
RAM Addr(1)
PORTB
9
Addr MUX
Instruction reg
7
Direct Addr
8
Indirect
Addr
FSR reg
STATUS reg
8
3
Power-up
Timer
Instruction
Decode &
Control
Oscillator
Start-up Timer
Timing
Generation
Watchdog
Timer
Brown-out
Reset
Power-on
Reset
OSC1/CLKI
OSC2/CLKO
MCLR
MUX
ALU
RB0/INT
RB1
RB2
RB3
RB4
RB5
RB6/PGC
RB7/PGD
PORTC
RC0/T1OSO/T1CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6
RC7
8
W reg
VDD, VSS
Timer0
Timer1
Timer2
A/D
Synchronous
Serial Port
CCP1
Note 1: Higher order bits are from the STATUS register.
© 2007 Microchip Technology Inc.
DS39597C-page 5
PIC16F72
TABLE 1-1:
PIC16F72 PINOUT DESCRIPTION
PDIP,
SOIC,
SSOP
Pin#
MLF
Pin#
I/O/P
Type
OSC1/CLKI
9
6
I
OSC2/CLKO
10
7
O
—
Oscillator crystal output. Connects to crystal or resonator in Crystal
Oscillator mode. In RC mode, the OSC2 pin outputs CLKO, which has
1/4 the frequency of OSC1, and denotes the instruction cycle rate.
MCLR/VPP
1
26
I/P
ST
Master Clear (Reset) input or programming voltage input. This pin is
an active low RESET to the device.
RA0/AN0
2
27
I/O
TTL
RA1/AN1
3
28
I/O
TTL
RA1 can also be analog input1.
RA2/AN2
4
1
I/O
TTL
RA2 can also be analog input2.
Pin Name
Buffer
Type
Description
ST/CMOS(3) Oscillator crystal input/external clock source input.
PORTA is a bi-directional I/O port.
RA0 can also be analog input0.
RA3/AN3/VREF
5
2
I/O
TTL
RA3 can also be analog input3 or analog reference voltage.
RA4/T0CKI
6
3
I/O
ST
RA4 can also be the clock input to the Timer0 module. Output is
open drain type.
RA5/AN4/SS
7
4
I/O
TTL
RA5 can also be analog input4 or the slave select for the
synchronous serial port.
PORTB is a bi-directional I/O port. PORTB can be software
programmed for internal weak pull-up on all inputs.
RB0/INT
21
18
I/O
TTL/ST(1)
RB1
22
19
I/O
TTL
RB2
23
20
I/O
TTL
RB3
24
21
I/O
TTL
RB4
25
22
I/O
TTL
Interrupt-on-change pin.
RB5
26
23
I/O
TTL
Interrupt-on-change pin.
RB6/PGC
27
24
I/O
TTL/ST(2)
RB7/PGD
28
25
I/O
TTL/ST(2)
RB0 can also be the external interrupt pin.
Interrupt-on-change pin. Serial programming clock.
Interrupt-on-change pin. Serial programming data.
PORTC is a bi-directional I/O port.
RC0/T1OSO/
T1CKI
11
8
I/O
ST
RC0 can also be the Timer1 oscillator output or Timer1 clock input.
RC1/T1OSI
12
9
I/O
ST
RC1 can also be the Timer1 oscillator input.
RC2/CCP1
13
10
I/O
ST
RC2 can also be the Capture1 input/Compare1 output/
PWM1 output.
RC3/SCK/SCL
14
11
I/O
ST
RC3 can also be the synchronous serial clock input/output for both
SPI and I2C modes.
RC4/SDI/SDA
15
12
I/O
ST
RC4 can also be the SPI Data In (SPI mode) or
Data I/O (I2C mode).
RC5/SDO
16
13
I/O
ST
RC5 can also be the SPI Data Out (SPI mode).
RC6
17
14
I/O
ST
RC7
18
15
I/O
ST
VSS
8, 19
5, 16
P
—
Ground reference for logic and I/O pins.
VDD
20
17
P
—
Positive supply for logic and I/O pins.
Legend: I = input
O = output
I/O = input/output
P = power
— = Not used
TTL = TTL input
ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt.
2: This buffer is a Schmitt Trigger input when used in Serial Programming mode.
3: This buffer is a Schmitt Trigger input when configured in RC Oscillator mode and a CMOS input otherwise.
DS39597C-page 6
© 2007 Microchip Technology Inc.
PIC16F72
2.0
MEMORY ORGANIZATION
There are two memory blocks in the PIC16F72 device.
These are the program memory and the data memory.
Each block has separate buses so that concurrent
access can occur. Program memory and data memory
are explained in this section. Program memory can be
read internally by the user code (see Section 7.0).
The data memory can further be broken down into the
general purpose RAM and the Special Function
Registers (SFRs). The operation of the SFRs that
control the “core” are described here. The SFRs used
to control the peripheral modules are described in the
section discussing each individual peripheral module.
Additional information on device memory may be found
in the PIC™ Mid-Range Reference Manual,
(DS33023).
2.1
Program Memory Organization
PIC16F72 devices have a 13-bit program counter capable of addressing a 8K x 14 program memory space.
The address range for this program memory is 0000h 07FFh. Accessing a location above the physically
implemented address will cause a wraparound.
The RESET Vector is at 0000h and the Interrupt Vector
is at 0004h.
FIGURE 2-1:
PROGRAM MEMORY MAP
AND STACK
2.2
Data Memory Organization
The Data Memory is partitioned into multiple banks that
contain the General Purpose Registers and the Special
Function Registers. Bits RP1 (STATUS<6>) and RP0
(STATUS<5>) are the bank select bits.
RP1:RP0
Bank
00
0
01
1
10
2
11
3
Each bank extends up to 7Fh (128 bytes). The lower
locations of each bank are reserved for the Special
Function Registers. Above the Special Function Registers are General Purpose Registers, implemented as
static RAM.
All implemented banks contain SFRs. Some “high use”
SFRs from one bank may be mirrored in another bank,
for code reduction and quicker access (e.g., the
STATUS register is in Banks 0 - 3).
2.2.1
GENERAL PURPOSE REGISTER
FILE
The register file can be accessed either directly, or indirectly, through the File Select Register FSR (see
Section 2.5).
PC<12:0>
CALL, RETURN
RETFIE, RETLW
13
Stack Level 1
User Memory
Space
Stack Level 8
RESET Vector
0000h
Interrupt Vector
0004h
0005h
On-chip Program
Memory
07FFh
0800h
1FFFh
© 2007 Microchip Technology Inc.
DS39597C-page 7
PIC16F72
FIGURE 2-2:
PIC16F72 REGISTER FILE MAP
File
Address
Indirect addr.(*)
TMR0
PCL
STATUS
FSR
PORTA
PORTB
PORTC
PCLATH
INTCON
PIR1
TMR1L
TMR1H
T1CON
TMR2
T2CON
SSPBUF
SSPCON
CCPR1L
CCPR1H
CCP1CON
ADRES
ADCON0
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
1Bh
1Ch
1Dh
1Eh
1Fh
20h
General
Purpose
Register
File
Address
Indirect addr.(*) 80h
OPTION
81h
PCL
82h
STATUS
83h
FSR
84h
TRISA
85h
TRISB
86h
TRISC
87h
88h
89h
PCLATH
8Ah
INTCON
8Bh
PIE1
8Ch
8Dh
PCON
8Eh
8Fh
90h
91h
PR2
92h
SSPADD
93h
SSPSTAT
94h
95h
96h
97h
98h
99h
9Ah
9Bh
9Ch
9Dh
9Eh
9Fh
ADCON1
General
A0h
Purpose
Register
BFh
32 Bytes
C0h
7Fh
Bank 0
Indirect addr.(*) 100h
101h
TMR0
102h
PCL
103h
STATUS
104h
FSR
105h
106h
PORTB
107h
108h
109h
10Ah
PCLATH
10Bh
INTCON
10Ch
PMDATL
PMADRL
10Dh
10Eh
PMDATH
10Fh
PMADRH
110h
accesses
40h-7Fh
96 Bytes
File
Address
File
Address
TRISB
PCLATH
INTCON
PMCON1
11Fh
120h
accesses
A0h -BFh
180h
181h
182h
183h
184h
185h
186h
187h
188h
189h
18Ah
18Bh
18Ch
18Dh
18Eh
18Fh
190h
19Fh
1A0h
1BFh
1C0h
accesses
20h-7Fh
accesses
40h -7Fh
17Fh
FFh
Bank 1
Indirect addr.(*)
OPTION
PCL
STATUS
FSR
Bank 2
1FFh
Bank 3
Unimplemented data memory locations, read as ‘0’.
* Not a physical register.
DS39597C-page 8
© 2007 Microchip Technology Inc.
PIC16F72
2.2.2
SPECIAL FUNCTION REGISTERS
The Special Function Registers can be classified into
two sets: core (CPU) and peripheral. Those registers
associated with the core functions are described in
detail in this section. Those related to the operation of
the peripheral features are described in detail in the
peripheral feature section.
The Special Function Registers are registers used by
the CPU and peripheral modules for controlling the
desired operation of the device. These registers are
implemented as static RAM. A list of these registers is
given in Table 2-1.
TABLE 2-1:
Address
Name
SPECIAL FUNCTION REGISTER SUMMARY
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on Details on
POR, BOR
page:
Bank 0
00h(1)
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000
01h
TMR0
Timer0 Module’s Register
02h(1)
PCL
Program Counter's (PC) Least Significant Byte
03h(1)
STATUS
04h(1)
FSR
05h
PORTA
06h
PORTB
07h
PORTC
19
xxxx xxxx
27,13
0000 0000
18
0001 1xxx
12
xxxx xxxx
19
--0x 0000
21
PORTB Data Latch when written: PORTB pins when read
xxxx xxxx
23
PORTC Data Latch when written: PORTC pins when read
xxxx xxxx
25
—
IRP
RP1
RP0
TO
PD
Z
DC
C
Indirect Data Memory Address Pointer
—
—
PORTA Data Latch when written: PORTA pins when read
08h
—
Unimplemented
—
09h
—
Unimplemented
—
—
---0 0000
18
0Ah(1,2) PCLATH
0Bh(1)
INTCON
0Ch
PIR1
—
—
—
Write Buffer for the upper 5 bits of the Program Counter
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x
14
—
ADIF
—
—
SSPIF
CCP1IF
TMR2IF
TMR1IF
-0-- 0000
16
0Dh
—
0Eh
TMR1L
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
0Fh
TMR1H
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
10h
T1CON
11h
TMR2
12h
T2CON
13h
SSPBUF
Unimplemented
—
—
T1CKPS1
T1CKPS0 T1OSCEN T1SYNC
—
SSPCON
CCPR1L
Capture/Compare/PWM Register (LSB)
16h
CCPR1H
Capture/Compare/PWM Register (MSB)
17h
CCP1CON
—
SSPOV
—
ADRES
A/D Result Register
1Fh
ADCON0
ADCS1
Note
1:
2:
3:
0000 0000
33
SSPEN
CCP1X
CKP
CCP1Y
SSPM3
CCP1M3
xxxx xxxx
SSPM2
CCP1M2
SSPM1
CCP1M1
SSPM0
CCP1M0
Unimplemented
1Eh
Legend:
29
29
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000
15h
—
29
xxxx xxxx
Synchronous Serial Port Receive Buffer/Transmit Register
WCOL
—
xxxx xxxx
TMR1ON --00 0000
Timer2 Module’s Register
14h
18h-1Dh
TMR1CS
—
ADCS0
CHS2
CHS1
CHS0
GO/DONE
—
ADON
34
43,48
0000 0000
45
xxxx xxxx
38,39,41
xxxx xxxx
38,39,41
--00 0000
37
—
—
xxxx xxxx
53
0000 00-0
53
x = unknown, u = unchanged, q = value depends on condition, - = unimplemented, read as ‘0’, r = reserved.
Shaded locations are unimplemented, read as ‘0’.
These registers can be addressed from any bank.
The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose
contents are transferred to the upper byte of the program counter.
This bit always reads as a ‘1’.
© 2007 Microchip Technology Inc.
DS39597C-page 9
PIC16F72
TABLE 2-1:
Address
Name
SPECIAL FUNCTION REGISTER SUMMARY (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on Details on
POR, BOR
page:
Bank 1
80h(1)
INDF
81h
OPTION
82h(1)
PCL
83h(1)
STATUS
84h(1)
FSR
Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000
RBPU
INTEDG
T0CS
T0SE
PS2
PS1
PS0
1111 1111
0000 0000
18
PD
Z
DC
C
0001 1xxx
12
xxxx xxxx
19
Program Counter's (PC) Least Significant Byte
IRP
RP1
RP0
TO
Indirect Data Memory Address Pointer
—
—
19
PSA
PORTA Data Direction Register
13
85h
TRISA
--11 1111
21
86h
TRISB
PORTB Data Direction Register
1111 1111
23
87h
TRISC
PORTC Data Direction Register
1111 1111
25
88h
—
Unimplemented
—
—
89h
—
Unimplemented
—
—
8Ah(1,2)
PCLATH
—
—
—
---0 0000
18
8Bh(1)
INTCON
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x
14
8Ch
PIE1
—
ADIE
—
—
SSPIE
CCP1IE
TMR2IE
TMR1IE
-0-- 0000
15
—
—
—
—
—
—
POR
BOR
---- --qq
17
Write Buffer for the upper 5 bits of the PC
8Dh
—
8Eh
PCON
Unimplemented
8Fh
—
Unimplemented
—
—
90h
—
Unimplemented
—
—
91h
—
Unimplemented
—
—
—
—
92h
PR2
Timer2 Period Register
1111 1111
41
93h
SSPADD
Synchronous Serial Port (I2C mode) Address Register
0000 0000
43,48
94h
SSPSTAT
0000 0000
44
SMP
CKE
D/A
P
S
R/W
UA
BF
95h
—
Unimplemented
—
—
96h
—
Unimplemented
—
—
97h
—
Unimplemented
—
—
98h
—
Unimplemented
—
—
99h
—
Unimplemented
—
—
9Ah
—
Unimplemented
—
—
9Bh
—
Unimplemented
—
—
9Ch
—
Unimplemented
—
—
9Dh
—
Unimplemented
—
—
9Eh
—
Unimplemented
—
—
---- -000
54
9Fh
ADCON1
Legend:
Note
1:
2:
3:
—
—
—
—
—
PCFG2
PCFG1
PCFG0
x = unknown, u = unchanged, q = value depends on condition, - = unimplemented, read as ‘0’, r = reserved.
Shaded locations are unimplemented, read as ‘0’.
These registers can be addressed from any bank.
The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose
contents are transferred to the upper byte of the program counter.
This bit always reads as a ‘1’.
DS39597C-page 10
© 2007 Microchip Technology Inc.
PIC16F72
TABLE 2-1:
Address
Name
SPECIAL FUNCTION REGISTER SUMMARY (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on Details on
POR, BOR
page:
Bank 2
100h(1)
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000
101h
TMR0
Timer0 Module’s Register
xxxx xxxx
27
102h(1
PCL
Program Counter's (PC) Least Significant Byte
0000 0000
18
103h(1)
STATUS
0001 1xxx
12
104h(1)
FSR
xxxx xxxx
19
105h
—
106h
IRP
RP1
RP0
TO
PD
Z
DC
C
Indirect Data Memory Address Pointer
PORTB
Unimplemented
PORTB Data Latch when written: PORTB pins when read
19
—
—
xxxx xxxx
23
107h
—
Unimplemented
—
—
108h
—
Unimplemented
—
—
109h
—
Unimplemented
—
—
---0 0000
18
10Ah(1,2) PCLATH
—
—
—
GIE
PEIE
TMR0IE
Write Buffer for the upper 5 bits of the Program Counter
10Bh(1)
INTCON
0000 000x
14
10Ch
PMDATL
Data Register Low Byte
xxxx xxxx
35
10Dh
PMADRL
Address Register Low Byte
xxxx xxxx
35
10Eh
PMDATH
—
—
10Fh
PMADRH
—
—
INTE
RBIE
TMR0IF
INTF
RBIF
Data Register High Byte
--xx xxxx
35
---x xxxx
35
Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000
19
—
Address Register High Byte
Bank 3
180h(1)
INDF
181h
OPTION
182h(1)
PCL
183h(1)
STATUS
184h(1)
FSR
—
186h
TRISB
187h
—
188h
—
189h
—
18Ah
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
IRP
RP1
RP0
TO
PD
Z
DC
C
Indirect Data Memory Address Pointer
185h
(1,2)
RBPU
Program Counter's (PC) Least Significant Byte
PCLATH
Unimplemented
1111 1111
13
0000 0000
18
0001 1xxx
12
xxxx xxxx
19
—
—
1111 1111
23
Unimplemented
—
—
Unimplemented
—
—
Unimplemented
—
—
---0 0000
18
PORTB Data Direction Register
—
—
—
Write Buffer for the upper 5 bits of the Program Counter
18Bh(1)
INTCON
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x
14
18Ch
PMCON1
— (3)
—
—
—
—
—
—
RD
1--- ---0
35
18Dh
—
Unimplemented
—
—
18Eh
—
Reserved, maintain clear
0000 0000
—
18Fh
—
Reserved, maintain clear
0000 0000
—
Legend:
Note
1:
2:
3:
x = unknown, u = unchanged, q = value depends on condition, - = unimplemented, read as ‘0’, r = reserved.
Shaded locations are unimplemented, read as ‘0’.
These registers can be addressed from any bank.
The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose
contents are transferred to the upper byte of the program counter.
This bit always reads as a ‘1’.
© 2007 Microchip Technology Inc.
DS39597C-page 11
PIC16F72
2.2.2.1
STATUS Register
The STATUS register, shown in Register 2-1, contains
the arithmetic status of the ALU, the RESET status and
the bank select bits for data memory.
The STATUS register can be the destination for any
instruction, as with any other register. If the STATUS
register is the destination for an instruction that affects
the Z, DC or C bits, then the write to these three bits is
disabled. These bits are set or cleared according to the
device logic. Furthermore, the TO and PD bits are not
writable. Therefore, the result of an instruction with the
STATUS register as destination may be different than
intended.
REGISTER 2-1:
For example, CLRF STATUS will clear the upper three
bits and set the Z bit. This leaves the STATUS register
as ‘000u u1uu’ (where u = unchanged).
It is recommended, therefore, that only BCF, BSF,
SWAPF and MOVWF instructions are used to alter the
STATUS register, because these instructions do not
affect the Z, C or DC bits from the STATUS register. For
other instructions, not affecting any status bits, see
Section 12.0, Instruction Set Summary.
Note 1: The C and DC bits operate as a borrow
and digit borrow bit, respectively, in subtraction. See the SUBLW and SUBWF
instructions for examples.
STATUS REGISTER (ADDRESS 03h, 83h, 103h, 183h)
R/W-0
R/W-0
R/W-0
R-1
R-1
R/W-x
R/W-x
R/W-x
IRP
RP1
RP0
TO
PD
Z
DC
C
bit 7
bit 0
bit 7
IRP: Register Bank Select bit (used for indirect addressing)
1 = Bank 2, 3 (100h - 1FFh)
0 = Bank 0, 1 (00h - FFh)
bit 6-5
RP<1:0>: Register Bank Select bits (used for direct addressing)
11 = Bank 3 (180h - 1FFh)
10 = Bank 2 (100h - 17Fh)
01 = Bank 1 (80h - FFh)
00 = Bank 0 (00h - 7Fh)
Each bank is 128 bytes
bit 4
TO: Time-out bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction
0 = A WDT time-out occurred
bit 3
PD: Power-down bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction
bit 2
Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero
bit 1
DC: Digit carry/borrow bit (ADDWF, ADDLW, SUBLW and SUBWF instructions)(1)
1 = A carry-out from the 4th low order bit of the result occurred
0 = No carry-out from the 4th low order bit of the result
bit 0
C: Carry/borrow bit (ADDWF, ADDLW, SUBLW and SUBWF instructions)(1,2)
1 = A carry-out from the Most Significant bit of the result occurred
0 = No carry-out from the Most Significant bit of the result occurred
Note 1: For borrow, the polarity is reversed. A subtraction is executed by adding the two’s
complement of the second operand.
2: For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low order
bit of the source register.
Legend:
DS39597C-page 12
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
© 2007 Microchip Technology Inc.
PIC16F72
2.2.2.2
OPTION Register
Note:
The OPTION register is a readable and writable register that contains various control bits to configure the
TMR0 prescaler/WDT postscaler (single assignable
register known also as the prescaler), the External INT
Interrupt, TMR0, and the weak pull-ups on PORTB.
REGISTER 2-2:
To achieve a 1:1 prescaler assignment for
the TMR0 register, assign the prescaler to
the Watchdog Timer.
OPTION REGISTER (ADDRESS 81h, 181h)
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
bit 7
bit 0
bit 7
RBPU: PORTB Pull-up Enable bit
1 = PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual port latch values
bit 6
INTEDG: Interrupt Edge Select bit
1 = Interrupt on rising edge of RB0/INT pin
0 = Interrupt on falling edge of RB0/INT pin
bit 5
T0CS: TMR0 Clock Source Select bit
1 = Transition on RA4/T0CKI pin
0 = Internal instruction cycle clock (CLKO)
bit 4
T0SE: TMR0 Source Edge Select bit
1 = Increment on high-to-low transition on RA4/T0CKI pin
0 = Increment on low-to-high transition on RA4/T0CKI pin
bit 3
PSA: Prescaler Assignment bit
1 = Prescaler is assigned to the WDT
0 = Prescaler is assigned to the Timer0 module
bit 2-0
PS2:PS0: Prescaler Rate Select bits
Bit Value TMR0 Rate WDT Rate
000
001
010
011
100
101
110
111
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
1:1
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
x = Bit is unknown
DS39597C-page 13
PIC16F72
2.2.2.3
INTCON Register
Note:
The INTCON Register is a readable and writable register that contains various enable and flag bits for the
TMR0 register overflow, RB Port change and External
RB0/INT pin interrupts.
REGISTER 2-3:
Interrupt flag bits get set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit or the global
enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to enabling an
interrupt.
INTCON: INTERRUPT CONTROL REGISTER (ADDRESS 0Bh, 8Bh, 10Bh, 18Bh)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-x
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
bit 7
bit 0
bit 7
GIE: Global Interrupt Enable bit
1 = Enables all unmasked interrupts
0 = Disables all interrupts
bit 6
PEIE: Peripheral Interrupt Enable bit
1 = Enables all unmasked peripheral interrupts
0 = Disables all peripheral interrupts
bit 5
TMR0IE: TMR0 Overflow Interrupt Enable bit
1 = Enables the TMR0 interrupt
0 = Disables the TMR0 interrupt
bit 4
INTE: RB0/INT External Interrupt Enable bit
1 = Enables the RB0/INT external interrupt
0 = Disables the RB0/INT external interrupt
bit 3
RBIE: RB Port Change Interrupt Enable bit
1 = Enables the RB port change interrupt
0 = Disables the RB port change interrupt
bit 2
TMR0IF: TMR0 Overflow Interrupt Flag bit
1 = TMR0 register has overflowed (must be cleared in software)
0 = TMR0 register did not overflow
bit 1
INTF: RB0/INT External Interrupt Flag bit
1 = The RB0/INT external interrupt occurred (must be cleared in software)
0 = The RB0/INT external interrupt did not occur
bit 0
RBIF: RB Port Change Interrupt Flag bit
A mismatch condition will continue to set flag bit RBIF. Reading PORTB will end the mismatch
condition and allow flag bit RBIF to be cleared.
1 = At least one of the RB7:RB4 pins changed state (must be cleared in software)
0 = None of the RB7:RB4 pins have changed state
Legend:
DS39597C-page 14
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
© 2007 Microchip Technology Inc.
PIC16F72
2.2.2.4
PIE1 Register
This register contains the individual enable bits for the
peripheral interrupts.
Note:
Bit PEIE (INTCON<6>) must be set to
enable any peripheral interrupt.
REGISTER 2-4:
PIE1: PERIPHERAL INTERRUPT ENABLE REGISTER 1 (ADDRESS 8Ch)
U-0
R/W-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIE
—
—
SSPIE
CCP1IE
TMR2IE
TMR1IE
bit 7
bit 0
bit 7
Unimplemented: Read as ‘0’
bit 6
ADIE: A/D Converter Interrupt Enable bit
1 = Enables the A/D converter interrupt
0 = Disables the A/D converter interrupt
bit 5-4
Unimplemented: Read as ‘0’
bit 3
SSPIE: Synchronous Serial Port Interrupt Enable bit
1 = Enables the SSP interrupt
0 = Disables the SSP interrupt
bit 2
CCP1IE: CCP1 Interrupt Enable bit
1 = Enables the CCP1 interrupt
0 = Disables the CCP1 interrupt
bit 1
TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
1 = Enables the TMR2 to PR2 match interrupt
0 = Disables the TMR2 to PR2 match interrupt
bit 0
TMR1IE: TMR1 Overflow Interrupt Enable bit
1 = Enables the TMR1 overflow interrupt
0 = Disables the TMR1 overflow interrupt
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
x = Bit is unknown
DS39597C-page 15
PIC16F72
2.2.2.5
PIR1 Register
This register contains the individual flag bits for the
Peripheral interrupts.
REGISTER 2-5:
PIR1: PERIPHERAL INTERRUPT FLAG REGISTER 1 (ADDRESS 0Ch)
U-0
R/W-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIF
—
—
SSPIF
CCP1IF
TMR2IF
TMR1IF
bit 7
bit 0
bit 7
Unimplemented: Read as ‘0’
bit 6
ADIF: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed
0 = The A/D conversion is not complete
bit 5-4
Unimplemented: Read as ‘0’
bit 3
SSPIF: Synchronous Serial Port (SSP) Interrupt Flag bit
1 = The SSP interrupt condition has occurred, and must be cleared in software before returning
from the Interrupt Service Routine.
The conditions that will set this bit are a transmission/reception has taken place.
0 = No SSP interrupt condition has occurred
bit 2
CCP1IF: CCP1 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode
bit 1
TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
1 = TMR2 to PR2 match occurred (must be cleared in software)
0 = No TMR2 to PR2 match occurred
bit 0
TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed (must be cleared in software)
0 = TMR1 register did not overflow
Legend:
DS39597C-page 16
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
© 2007 Microchip Technology Inc.
PIC16F72
2.2.2.6
Note:
PCON Register
Note:
Interrupt flag bits get set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit or the global
enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to enabling an
interrupt.
BOR is unknown on Power-on Reset. It
must then be set by the user and checked
on subsequent RESETS to see if BOR is
clear, indicating a brown-out has occurred.
The BOR status bit is a ‘don't care’ and is
not necessarily predictable if the brown-out
circuit is disabled (by clearing the BOREN
bit in the Configuration word).
The Power Control (PCON) register contains a flag bit
to allow differentiation between a Power-on Reset
(POR), a Brown-out Reset, an external MCLR Reset
and WDT Reset.
REGISTER 2-6:
PCON: POWER CONTROL REGISTER (ADDRESS 8Eh)
U-0
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-x
—
—
—
—
—
—
POR
BOR
bit 7
bit 0
bit 7-2
Unimplemented: Read as ‘0’
bit 1
POR: Power-on Reset Status bit
1 = No Power-on Reset occurred
0 = A Power-on Reset occurred (must be set in software after a Power-on Reset occurs)
bit 0
BOR: Brown-out Reset Status bit
1 = No Brown-out Reset occurred
0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs)
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
x = Bit is unknown
DS39597C-page 17
PIC16F72
2.3
PCL and PCLATH
Figure 2-3 shows the four situations for the loading of
the PC.
The program counter (PC) specifies the address of the
instruction to fetch for execution. The PC is 13-bits
wide. The low byte is called the PCL register. This register is readable and writable. The high byte is called
the PCH register. This register contains the PC<12:8>
bits and is not directly readable or writable. All updates
to the PCH register go through the PCLATH register.
FIGURE 2-3:
• Example 1 shows how the PC is loaded on a write
to PCL (PCLATH<4:0> → PCH).
• Example 2 shows how the PC is loaded during a
GOTO instruction (PCLATH<4:3> → PCH).
• Example 3 shows how the PC is loaded during a
CALL instruction (PCLATH<4:3> → PCH), with
the PC loaded (PUSH’d) onto the Top-of-Stack.
• Example 4 shows how the PC is loaded during
one of the return instructions, where the PC is
loaded (POP’d) from the Top-of-Stack.
LOADING OF PC IN DIFFERENT SITUATIONS
Example 1 - Instruction with PCL as destination
PCH
Top-of-Stack
PCL
12
8
Stack (13-bits x 8)
7
0
PC
5
8
PCLATH<4:0>
ALU result
PCLATH
Stack (13-bits x 8)
Example 2 - GOTO Instruction
PCH
12
11 10
Top-of-Stack
PCL
8
0
7
PC
2
11
PCLATH<4:3>
Opcode <10:0>
PCLATH
Example 3 - CALL Instruction
Stack (13-bits x 8)
13
Top-of-Stack
PCH
12
11 10
PCL
8
0
7
PC
2
PCLATH<4:3>
11
Opcode <10:0>
PCLATH
Example 4 - RETURN, RETFIE, or RETLW Instruction
13
Stack (13-bits x 8)
Top-of-Stack
PCH
12
11 10
PCL
8
7
0
PC
11
Opcode <10:0>
PCLATH
Note: PCLATH is not updated with the contents of PCH.
DS39597C-page 18
© 2007 Microchip Technology Inc.
PIC16F72
2.3.1
COMPUTED GOTO
2.4
A computed GOTO is accomplished by adding an offset
to the program counter (ADDWF PCL). When doing a
table read using a computed GOTO method, care
should be exercised if the table location crosses a PCL
memory boundary (each 256-byte block). Refer to the
Application Note, “Implementing a Table Read"
(AN556).
2.3.2
STACK
The stack allows a combination of up to eight program
calls and interrupts to occur. The stack contains the
return address from this branch in program execution.
Mid-range devices have an 8-level deep x 13-bit wide
hardware stack. The stack space is not part of either
program or data space and the stack pointer is not
readable or writable. The PC is PUSH’d onto the stack
when a CALL instruction is executed, or an interrupt
causes a branch. The stack is POP’d in the event of a
RETURN, RETLW or a RETFIE instruction execution.
PCLATH is not modified when the stack is PUSH’d or
POP’d.
After the stack has been PUSH’d eight times, the ninth
push overwrites the value that was stored from the first
push. The tenth push overwrites the second push (and
so on). An example of the overwriting of the stack is
shown in Figure 2-4.
FIGURE 2-4:
STACK MODIFICATION
The CALL and GOTO instructions provide 11 bits of
address to allow branching within any 2K program
memory page. When doing a CALL or GOTO instruction,
the upper two bits of the address are provided by
PCLATH<4:3>. When doing a CALL or GOTO instruction, the user must ensure that the page select bits are
programmed so that the desired program memory
page is addressed. If a return from a CALL instruction
(or interrupt) is executed, the entire 13-bit PC is pushed
onto the stack. Therefore, manipulation of the
PCLATH<4:3> bits is not required for the return
instructions (which POPs the address from the stack).
Note:
2.5
The PIC16F72 device ignores the paging
bit
PCLATH<4:3>.
The
use
of
PCLATH<4:3> as a general purpose read/
write bit is not recommended, since this
may affect upward compatibility with future
products.
Indirect Addressing, INDF and
FSR Registers
The INDF register is not a physical register. Addressing INDF actually addresses the register whose
address is contained in the FSR register (FSR is a
pointer). This is indirect addressing.
A simple program to clear RAM locations 20h-2Fh
using indirect addressing is shown in Example 2-1.
EXAMPLE 2-1:
Stack
Push1 Push9
Push2 Push10
Push3
Push4
Push5
Push6
Push7
Push8
Program Memory Paging
Top-of-Stack
NEXT
movlw
movwf
clrf
incf
btfss
goto
INDIRECT ADDRESSING
0x20
FSR
INDF
FSR
FSR,4
NEXT
;initialize pointer
;to RAM
;clear INDF register
;inc pointer
;all done?
;NO, clear next
CONTINUE
:
;YES, continue
An effective 9-bit address is obtained by concatenating
the 8-bit FSR register and the IRP bit (STATUS<7>), as
shown in Figure 2-5.
Note 1: There are no status bits to indicate stack
overflow or stack underflow conditions.
2: There are no instructions/mnemonics
called PUSH or POP. These are actions
that occur from the execution of the
CALL, RETURN, RETLW and RETFIE
instructions, or the vectoring to an
interrupt address.
© 2007 Microchip Technology Inc.
DS39597C-page 19
PIC16F72
FIGURE 2-5:
DIRECT/INDIRECT ADDRESSING
Direct Addressing
RP1:RP0
6
Indirect Addressing
From Opcode
0
IRP
7
Bank Select
Bank Select Location Select
00
01
10
FSR Register
0
Location Select
11
00h
80h
100h
180h
7Fh
FFh
17Fh
1FFh
Data
Memory(1)
Bank 0
Bank 1
Bank 2
Bank 3
Note 1: For register file map detail, see Figure 2-2.
DS39597C-page 20
© 2007 Microchip Technology Inc.
PIC16F72
3.0
I/O PORTS
FIGURE 3-1:
Some pins for these I/O ports are multiplexed with an
alternate function for the peripheral features on the
device. In general, when a peripheral is enabled, that
pin may not be used as a general purpose I/O pin.
Additional information on I/O ports may be found in the
PIC™ Mid-Range
MCU
Reference Manual,
(DS33023).
3.1
Data
Bus
D
Q
VDD
WR
Port
VDD
Q
CK
P
Data Latch
PORTA and the TRISA Register
PORTA is a 6-bit wide, bi-directional port. The corresponding data direction register is TRISA. Setting a
TRISA bit (= 1) will make the corresponding PORTA pin
an input (i.e., put the corresponding output driver in a
Hi-Impedance mode). Clearing a TRISA bit (= 0) will
make the corresponding PORTA pin an output (i.e., put
the contents of the output latch on the selected pin).
BLOCK DIAGRAM OF
RA3:RA0 AND RA5 PINS
D
WR
TRIS
CK
Q
N
Q
VSS
Other PORTA pins are multiplexed with analog inputs
and analog VREF input. The operation of each pin is
selected by clearing/setting the control bits in the
ADCON1 register (A/D Control Register1).
Note:
On a Power-on Reset, these pins are configured as analog inputs and read as ‘0’.
The TRISA register controls the direction of the RA
pins, even when they are being used as analog inputs.
The user must ensure the bits in the TRISA register are
maintained set when using them as analog inputs.
EXAMPLE 3-1:
BANKSEL
CLRF
BANKSEL
MOVLW
MOVWF
MOVLW
MOVWF
PORTA
PORTA
INITIALIZING PORTA
;
;
;
;
ADCON1 ;
0x06
;
ADCON1 ;
0xCF
;
;
;
TRISA
;
;
;
;
select bank for PORTA
Initialize PORTA by
clearing output
data latches
Select Bank for ADCON1
Configure all pins
as digital inputs
Value used to
initialize data
direction
Set RA<3:0> as inputs
RA<5:4> as outputs
TRISA<7:6> are always
read as ‘0’.
© 2007 Microchip Technology Inc.
VSS
Analog
Input
Mode
TRIS Latch
RD TRIS
Reading the PORTA register, reads the status of the
pins, whereas writing to it will write to the port latch. All
write operations are read-modify-write operations.
Therefore, a write to a port implies that the port pins are
read, this value is modified and then written to the port
data latch.
Pin RA4 is multiplexed with the Timer0 module clock
input to become the RA4/T0CKI pin. The RA4/T0CKI
pin is a Schmitt Trigger input and an open drain output.
All other RA port pins have TTL input levels and full
CMOS output drivers.
I/O pin
TTL
Input
Buffer
Q
D
EN
RD Port
To A/D Converter
FIGURE 3-2:
Data
Bus
WR
Port
BLOCK DIAGRAM OF
RA4/T0CKI PIN
D
Q
CK
Q
D
WR
TRIS
I/O pin
N
Data Latch
VSS
Q
VSS
CK
Q
Schmitt
Trigger
Input
Buffer
TRIS Latch
RD TRIS
Q
D
ENEN
RD Port
TMR0 Clock Input
DS39597C-page 21
PIC16F72
TABLE 3-1:
PORTA FUNCTIONS
Name
Bit#
Buffer Function
RA0/AN0
bit 0
TTL
Input/output or analog input.
RA1/AN1
bit 1
TTL
Input/output or analog input.
RA2/AN2
bit 2
TTL
Input/output or analog input.
RA3/AN3/VREF
bit 3
TTL
Input/output or analog input or VREF.
RA4/T0CKI
bit 4
ST
Input/output or external clock input for Timer0. Output is open drain type.
RA5/AN4/SS
bit 5
TTL
Input/output or analog input or slave select input for synchronous serial port.
Legend: TTL = TTL input, ST = Schmitt Trigger input
TABLE 3-2:
Address
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Name
Bit 7
Bit 6
05h
PORTA
—
—
85h
TRISA
—
—
9Fh
ADCON1
—
—
Value on
all other
RESETS
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
RA5
RA4
RA3
RA2
RA1
RA0
--0x 0000 --0u 0000
PORTA Data Direction Register
—
—
—
--11 1111 --11 1111
PCFG2 PCFG1 PCFG0 ---- -000 ---- -000
Legend: x = unknown, u = unchanged, - = unimplemented locations read as ‘0’.
Shaded cells are not used by PORTA.
Note:
When using the SSP module in SPI Slave mode and SS enabled, the A/D Port Configuration Control bits
(PCFG2:PCFG0) in the A/D Control Register (ADCON1) must be set to one of the following configurations:
100, 101, 11x.
DS39597C-page 22
© 2007 Microchip Technology Inc.
PIC16F72
3.2
PORTB and the TRISB Register
PORTB is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISB. Setting a
TRISB bit (= 1) will make the corresponding PORTB
pin an input (i.e., put the corresponding output driver in
a Hi-Impedance mode). Clearing a TRISB bit (= 0) will
make the corresponding PORTB pin an output (i.e., put
the contents of the output latch on the selected pin).
EXAMPLE 3-2:
BANKSEL
CLRF
PORTB
PORTB
BANKSEL
MOVLW
TRISB
0xCF
MOVWF
TRISB
INITIALIZING PORTB
;
;
;
;
;
;
;
;
;
;
;
Select bank for PORTB
Initialize PORTB by
clearing output
data latches
Select Bank for TRISB
Value used to
initialize data
direction
Set RB<3:0> as inputs
RB<5:4> as outputs
RB<7:6> as inputs
Each of the PORTB pins has a weak internal pull-up. A
single control bit can turn on all the pull-ups. This is performed by clearing bit RBPU (OPTION<7>). The weak
pull-up is automatically turned off when the port pin is
configured as an output. The pull-ups are disabled on a
Power-on Reset.
FIGURE 3-3:
BLOCK DIAGRAM OF
RB3:RB0 PINS
are compared with the old value latched on the last
read of PORTB. The “mismatch” outputs of RB7:RB4
are OR’d together to generate the RB Port Change
Interrupt with flag bit RBIF (INTCON<0>).
This interrupt can wake the device from SLEEP. The
user, in the Interrupt Service Routine, can clear the
interrupt in the following manner:
a)
b)
Any read or write of PORTB. This will end the
mismatch condition.
Clear flag bit RBIF.
A mismatch condition will continue to set flag bit RBIF.
Reading PORTB will end the mismatch condition and
allow flag bit RBIF to be cleared.
The interrupt-on-change feature is recommended for
wake-up on key depression operation and operations
where PORTB is only used for the interrupt-on-change
feature. Polling of PORTB is not recommended while
using the interrupt-on-change feature.
This interrupt-on-mismatch feature, together with software configurable pull-ups on these four pins, allow
easy interface to a keypad and make it possible for
wake-up on key depression. Refer to the Embedded
Control Handbook, “Implementing Wake-Up on Key
Stroke” (AN552).
RB0/INT is an external interrupt input pin and is
configured using the INTEDG bit (OPTION<6>).
FIGURE 3-4:
BLOCK DIAGRAM OF
RB7:RB4 PINS
VDD
RBPU(1)
Data
Bus
Data Latch
D
WR
Port
VDD
RBPU(1)
VDD
P Weak
Pull-up
Data
Bus
Q
I/O pin
CK
TRIS Latch
D
Q
WR
TRIS
WR
Port
CK
WR
TRIS
RD TRIS
D
Q
I/O pin
CK
VSS
TTL
Input
Buffer
CK
RD TRIS
Q
RD Port
Data Latch
TRIS Latch
D
Q
VSS
TTL
Input
Buffer
VDD
P Weak
Pull-up
D
Q
EN
Set RBIF
Latch
D
EN
RD Port
ST
Buffer
Q1
RB0/INT
Schmitt Trigger
Buffer
RD Port
Note 1: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU bit (OPTION<7>).
Q
From Other
RB7:RB4 Pins
D
RD Port
EN
Q3
RB7:RB6 in Serial Programming Mode
Four of PORTB’s pins, RB7:RB4, have an interrupt-onchange feature. Only pins configured as inputs can
cause this interrupt to occur (i.e., any RB7:RB4 pin
configured as an output is excluded from the interrupt
on change comparison). The input pins (of RB7:RB4)
© 2007 Microchip Technology Inc.
Note 1: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU bit (OPTION<7>).
DS39597C-page 23
PIC16F72
TABLE 3-3:
PORTB FUNCTIONS
Name
Bit#
Buffer
Function
RB0/INT
bit 0
TTL/ST(1)
RB1
bit 1
TTL
Input/output pin. Internal software programmable weak pull-up.
RB2
bit 2
TTL
Input/output pin. Internal software programmable weak pull-up.
RB3
bit 3
TTL
Input/output pin. Internal software programmable weak pull-up.
RB4
bit 4
TTL
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up.
RB5
bit 5
TTL
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up.
RB6
bit 6
TTL/ST(2)
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up. Serial programming clock.
RB7
bit 7
TTL/ST(2)
Input/output pin (with interrupt-on-change). Internal software programmable
weak pull-up. Serial programming data.
Input/output pin or external interrupt input. Internal software
programmable weak pull-up.
Legend: TTL = TTL input, ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt.
2: This buffer is a Schmitt Trigger input when used in Serial Programming mode.
TABLE 3-4:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3 Bit 2 Bit 1 Bit 0
Value on
POR, BOR
Value on
all other
RESETS
06h, 106h
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
uuuu uuuu
1111 1111
1111 1111
PSA
PS2
PS1
PS0
1111 1111
1111 1111
86h, 186h
TRISB
PORTB Data Direction Register
81h, 181h
OPTION
RBPU
INTEDG
T0CS T0SE
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTB.
DS39597C-page 24
© 2007 Microchip Technology Inc.
PIC16F72
3.3
PORTC and the TRISC Register
PORTC is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISC. Setting a
TRISC bit (= 1) will make the corresponding PORTC
pin an input (i.e., put the corresponding output driver in
a Hi-Impedance mode). Clearing a TRISC bit (= 0) will
make the corresponding PORTC pin an output (i.e., put
the contents of the output latch on the selected pin).
PORTC is multiplexed with several peripheral functions
(Table 3-5). PORTC pins have Schmitt Trigger input
buffers.
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTC pin. Some
peripherals override the TRIS bit to make a pin an output, while other peripherals override the TRIS bit to
make a pin an input. Since the TRIS bit override is in
effect while the peripheral is enabled, read-modifywrite instructions (BSF, BCF, XORWF) with TRISC as
destination should be avoided. The user should refer to
the corresponding peripheral section for the correct
TRIS bit settings.
EXAMPLE 3-3:
BANKSEL
CLRF
PORTC
PORTC
BANKSEL
MOVLW
TRISC
0xCF
MOVWF
TRISC
INITIALIZING PORTC
;
;
;
;
;
;
;
;
;
;
;
Select Bank for PORTC
Initialize PORTC by
clearing output
data latches
Select Bank for TRISC
Value used to
initialize data
direction
Set RC<3:0> as inputs
RC<5:4> as outputs
RC<7:6> as inputs
© 2007 Microchip Technology Inc.
FIGURE 3-5:
PORTC BLOCK DIAGRAM
(PERIPHERAL OUTPUT
OVERRIDE)
Port/Peripheral Select(1)
Peripheral Data Out
Data
Bus
WR
Port
0
D
CK
VDD
Q
Q
P
VDD
1
Data Latch
WR
TRIS
D
CK
I/O
pin
Q
Q
N
VSS
TRIS Latch
VSS
Schmitt
Trigger
RD TRIS
Peripheral
OE(2)
Q
RD
Port
D
EN
Peripheral Input
Note 1: Port/Peripheral select signal selects
between port data and peripheral output.
2: Peripheral OE (output enable) is only
activated if peripheral select is active.
DS39597C-page 25
PIC16F72
TABLE 3-5:
PORTC FUNCTIONS
Name
Bit#
Buffer Type
Function
RC0/T1OSO/T1CKI
bit 0
ST
Input/output port pin or Timer1 oscillator output/Timer1 clock input.
RC1/T1OSI
bit 1
ST
Input/output port pin or Timer1 oscillator input.
RC2/CCP1
bit 2
ST
Input/output port pin or Capture1 input/Compare1 output/PWM1
output.
RC3/SCK/SCL
bit 3
ST
RC3 can also be the synchronous serial clock for both SPI and I2C
modes.
RC4/SDI/SDA
bit 4
ST
RC4 can also be the SPI Data In (SPI mode) or data I/O (I2C mode).
RC5/SDO
bit 5
ST
Input/output port pin or Synchronous Serial Port data output.
RC6
bit 6
ST
Input/output port pin.
RC7
bit 7
ST
Input/output port pin.
Legend: ST = Schmitt Trigger input
TABLE 3-6:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
Value on
all other
RESETS
Address Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
07h
PORTC
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
xxxx xxxx uuuu uuuu
87h
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
Legend: x = unknown, u = unchanged
DS39597C-page 26
© 2007 Microchip Technology Inc.
PIC16F72
4.0
TIMER0 MODULE
Counter mode is selected by setting bit T0CS
(OPTION<5>). In Counter mode, Timer0 will increment, either on every rising or falling edge of pin RA4/
T0CKI. The incrementing edge is determined by the
Timer0 Source Edge Select bit T0SE (OPTION<4>).
Clearing bit T0SE selects the rising edge. Restrictions
on the external clock input are discussed in detail in
Section 4.3.
The Timer0 module timer/counter has the following
features:
•
•
•
•
•
•
8-bit timer/counter
Readable and writable
8-bit software programmable prescaler
Internal or external clock select
Interrupt on overflow from FFh to 00h
Edge select for external clock
The prescaler is mutually exclusively shared between
the Timer0 module and the Watchdog Timer. The prescaler is not readable or writable. Section 4.4 details the
operation of the prescaler.
Figure 4-1 is a block diagram of the Timer0 module and
the prescaler shared with the WDT.
4.2
Additional information on the Timer0 module is
available in the PIC™ Mid-Range MCU Family
Reference Manual (DS33023).
4.1
The TMR0 interrupt is generated when the TMR0 register overflows from FFh to 00h. This overflow sets bit
TMR0IF (INTCON<2>). The interrupt can be masked
by clearing bit TMR0IE (INTCON<5>). Bit TMR0IF
must be cleared in software by the Timer0 module
Interrupt Service Routine, before re-enabling this interrupt. The TMR0 interrupt cannot awaken the processor
from SLEEP, since the timer is shut-off during SLEEP.
Timer0 Operation
Timer mode is selected by clearing bit T0CS
(OPTION<5>). In Timer mode, the Timer0 module will
increment every instruction cycle (without prescaler). If
the TMR0 register is written, the increment is inhibited
for the following two instruction cycles. The user can
work around this by writing an adjusted value to the
TMR0 register.
FIGURE 4-1:
Timer0 Interrupt
BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER
CLKO (= FOSC/4)
Data Bus
0
8
M
U
X
1
0
1
RA4/T0CKI
pin
T0SE
M
U
X
T0CS
SYNC
2
Cycles
TMR0 reg
Set Flag bit TMR0IF
on Overflow
PSA
PRESCALER
0
Watchdog
Timer
1
M
U
X
8-bit Prescaler
8
8 - to - 1MUX
PS2:PS0
PSA
WDT Enable bit
1
0
MUX
PSA
WDT
Time-out
Note: T0CS, T0SE, PSA, PS2:PS0 are (OPTION<5:0>).
© 2007 Microchip Technology Inc.
DS39597C-page 27
PIC16F72
4.3
Using Timer0 with an External
Clock
Timer0 module means that there is no prescaler for the
Watchdog Timer, and vice-versa. This prescaler is not
readable or writable (see Figure 4-1).
When no prescaler is used, the external clock input is
the same as the prescaler output. The synchronization
of T0CKI, with the internal phase clocks, is accomplished by sampling the prescaler output on the Q2 and
Q4 cycles of the internal phase clocks. Therefore, it is
necessary for T0CKI to be high for at least 2 TOSC (and
a small RC delay of 20 ns) and low for at least 2 TOSC
(and a small RC delay of 20 ns). Refer to the electrical
specification of the desired device.
4.4
The PSA and PS2:PS0 bits (OPTION<3:0>) determine
the prescaler assignment and prescale ratio.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g., CLRF 1, MOVWF 1,
BSF
1,x....etc.) will clear the prescaler. When
assigned to WDT, a CLRWDT instruction will clear the
prescaler along with the Watchdog Timer. The
prescaler is not readable or writable.
Note:
Prescaler
There is only one prescaler available, which is mutually
exclusively shared between the Timer0 module and the
Watchdog Timer. A prescaler assignment for the
TABLE 4-1:
Address
01h,101h
REGISTERS ASSOCIATED WITH TIMER0
Name
TMR0
0Bh,8Bh, INTCON
10Bh,18Bh
81h,181h
Writing to TMR0 when the prescaler is
assigned to Timer0, will clear the prescaler
count but will not change the prescaler
assignment.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Timer0 Module Register
GIE
PEIE
OPTION RBPU INTEDG
Value on
all other
RESETS
xxxx xxxx uuuu uuuu
TMR0IE INTE
T0CS
Value on
POR, BOR
T0SE
RBIE TMR0IF INTF
RBIF 0000 000x 0000 000u
PSA
PS0
PS2
PS1
1111 1111 1111 1111
Legend: x = unknown, u = unchanged, - = unimplemented locations read as ‘0’. Shaded cells are not used by Timer0.
DS39597C-page 28
© 2007 Microchip Technology Inc.
PIC16F72
5.0
TIMER1 MODULE
5.1
The Timer1 module timer/counter has the following
features:
• 16-bit timer/counter
(Two 8-bit registers; TMR1H and TMR1L)
• Readable and writable (both registers)
• Internal or external clock select
• Interrupt on overflow from FFFFh to 0000h
• RESET from CCP module trigger
Timer1 Operation
Timer1 can operate in one of these modes:
• As a timer
• As a synchronous counter
• As an asynchronous counter
The Operating mode is determined by the clock select
bit, TMR1CS (T1CON<1>).
Timer1 has a control register, shown in Register 5-1.
Timer1 can be enabled/disabled by setting/clearing
control bit TMR1ON (T1CON<0>).
In Timer mode, Timer1 increments every instruction
cycle. In Counter mode, it increments on every rising
edge of the external clock input.
Figure 5-2 is a simplified block diagram of the Timer1
module.
When the Timer1 oscillator is enabled (T1OSCEN is
set), the RC1/T1OSI and RC0/T1OSO/T1CKI pins
become inputs. That is, the TRISC<1:0> value is
ignored.
Additional information on timer modules is available in
the PIC™ Mid-Range MCU Reference Manual,
(DS33023).
Timer1 also has an internal “RESET input”. This
RESET can be generated by the CCP module
(Section 8.0).
REGISTER 5-1:
T1CON: TIMER1 CONTROL REGISTER (ADDRESS 10h)
U-0
U-0
R/W-0
R/W-0
—
—
T1CKPS1
T1CKPS0
R/W-0
R/W-0
R/W-0
T1OSCEN T1SYNC TMR1CS
R/W-0
TMR1ON
bit 7
bit 0
bit 7-6
Unimplemented: Read as ‘0’
bit 5-4
T1CKPS1:T1CKPS0: Timer1 Input Clock Prescale Select bits
11 = 1:8 Prescale value
10 = 1:4 Prescale value
01 = 1:2 Prescale value
00 = 1:1 Prescale value
bit 3
T1OSCEN: Timer1 Oscillator Enable Control bit
1 = Oscillator is enabled
0 = Oscillator is shut-off (The oscillator inverter is turned off to eliminate power drain.)
bit 2
T1SYNC: Timer1 External Clock Input Synchronization Control bit
TMR1CS = 1:
1 = Do not synchronize external clock input
0 = Synchronize external clock input
TMR1CS = 0:
This bit is ignored. Timer1 uses the internal clock when TMR1CS = ‘0’.
bit 1
TMR1CS: Timer1 Clock Source Select bit
1 = External clock from pin RC0/T1OSO/T1CKI (on the rising edge)
0 = Internal clock (FOSC/4)
bit 0
TMR1ON: Timer1 On bit
1 = Enables Timer1
0 = Stops Timer1
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
x = Bit is unknown
DS39597C-page 29
PIC16F72
5.2
Timer1 Operation in Timer Mode
5.4
Timer mode is selected by clearing the TMR1CS
(T1CON<1>) bit. In this mode, the input clock to the
timer is FOSC/4. The synchronize control bit T1SYNC
(T1CON<2>) has no effect, since the internal clock is
always in sync.
5.3
Counter mode is selected by setting bit TMR1CS. In
this mode, the timer increments on every rising edge of
clock input on pin RC1/T1OSI when bit T1OSCEN is
set, or on pin RC0/T1OSO/T1CKI when bit T1OSCEN
is cleared.
Timer1 Counter Operation
If T1SYNC is cleared, then the external clock input is
synchronized with internal phase clocks. The synchronization is done after the prescaler stage. The
prescaler stage is an asynchronous ripple counter.
Timer1 may operate in Asynchronous or Synchronous
mode, depending on the setting of the TMR1CS bit.
When Timer1 is being incremented via an external
source, increments occur on a rising edge. After Timer1
is enabled in Counter mode, the module must first have
a falling edge before the counter begins to increment.
FIGURE 5-1:
Timer1 Operation in Synchronized
Counter Mode
In this configuration, during SLEEP mode, Timer1 will
not increment even if the external clock is present,
since the synchronization circuit is shut-off. The
prescaler, however, will continue to increment.
TIMER1 INCREMENTING EDGE
T1CKI
(Default High)
T1CKI
(Default Low)
Note: Arrows indicate counter increments.
FIGURE 5-2:
TIMER1 BLOCK DIAGRAM
Set Flag bit
TMR1IF on
Overflow
TMR1H
Synchronized
Clock Input
0
TMR1
TMR1L
1
TMR1ON
On/Off
T1OSC
RC0/T1OSO/T1CKI
RC1/T1OSI
T1SYNC
(2)
1
T1OSCEN FOSC/4
Enable
Internal
Oscillator(1) Clock
Synchronize
Prescaler
1, 2, 4, 8
det
0
2
T1CKPS1:T1CKPS0
TMR1CS
Q Clock
Note 1: When the T1OSCEN bit is cleared, the inverter is turned off. This eliminates power drain.
DS39597C-page 30
© 2007 Microchip Technology Inc.
PIC16F72
5.5
Timer1 Operation in
Asynchronous Counter Mode
If control bit T1SYNC (T1CON<2>) is set, the external
clock input is not synchronized. The timer continues to
increment asynchronous to the internal phase clocks.
The timer will continue to run during SLEEP and can
generate an interrupt on overflow, that will wake-up the
processor. However, special precautions in software
are needed to read/write the timer (Section 5.5.1).
In Asynchronous Counter mode, Timer1 cannot be
used as a time base for capture or compare operations.
5.5.1
For writes, it is recommended that the user simply stop
the timer and write the desired values. A write contention may occur by writing to the timer registers, while
the register is incrementing. This may produce an
unpredictable value in the timer register. Data in the
Timer1 register (TMR1) may become corrupted. Corruption occurs when the timer enable is turned off at the
same instant that a ripple carry occurs in the timer
module.
Reading the 16-bit value requires some care. Examples 12-2 and 12-3 in the PIC™ Mid-Range MCU
Family Reference Manual (DS33023) show how to
read and write Timer1 when it is running in
Asynchronous mode.
Timer1 Oscillator
A crystal oscillator circuit is built between pins T1OSI
(input) and T1OSO (amplifier output). It is enabled by
setting control bit T1OSCEN (T1CON<3>). The oscillator is a low power oscillator rated up to 200 kHz. It will
continue to run during SLEEP. It is primarily intended
for a 32 kHz crystal. Table 5-1 shows the capacitor
selection for the Timer1 oscillator.
The Timer1 oscillator is identical to the LP oscillator.
The user must provide a software time delay to ensure
proper oscillator start-up.
© 2007 Microchip Technology Inc.
CAPACITOR SELECTION FOR
THE TIMER1 OSCILLATOR
Osc Type
Freq
C1
C2
LP
32 kHz
33 pF
33 pF
100 kHz
15 pF
15 pF
200 kHz
15 pF
15 pF
These values are for design guidance only.
Note 1: Higher capacitance increases the stability
of oscillator, but also increases the start-up
time.
2: Since each resonator/crystal has its own
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate
values
of
external
components.
READING AND WRITING TIMER1 IN
ASYNCHRONOUS COUNTER
MODE
Reading TMR1H or TMR1L while the timer is running
from an external asynchronous clock will ensure a valid
read (taken care of in hardware). However, the user
should keep in mind that reading the 16-bit timer in two
8-bit values itself, poses certain problems, since the
timer may overflow between the reads.
5.6
TABLE 5-1:
5.7
Timer1 Interrupt
The TMR1 register pair (TMR1H:TMR1L) increments
from 0000h to FFFFh and rolls over to 0000h. The
TMR1 interrupt, if enabled, is generated on overflow,
which is latched in interrupt flag bit TMR1IF (PIR1<0>).
This interrupt can be enabled/disabled by setting/
clearing TMR1 interrupt enable bit TMR1IE (PIE1<0>).
5.8
Resetting Timer1 Using a CCP
Trigger Output
If the CCP module is configured in Compare mode to
generate
a
“special
event
trigger"
signal
(CCP1M3:CCP1M0 = 1011), the signal will reset
Timer1 and start an A/D conversion (if the A/D module
is enabled).
Note:
The special event triggers from the CCP1
module will not set interrupt flag bit
TMR1IF (PIR1<0>).
Timer1 must be configured for either Timer or Synchronized Counter mode to take advantage of this feature.
If Timer1 is running in Asynchronous Counter mode,
this RESET operation may not work.
In the event that a write to Timer1 coincides with a
special event trigger from CCP1, the write will take
precedence.
In this mode of operation, the CCPR1H:CCPR1L registers pair effectively becomes the period register for
Timer1.
DS39597C-page 31
PIC16F72
5.9
Resetting Timer1 Register Pair
(TMR1H, TMR1L)
5.10
Timer1 Prescaler
The prescaler counter is cleared on writes to the
TMR1H or TMR1L registers.
TMR1H and TMR1L registers are not reset to 00h on a
POR, or any other RESET, except by the CCP1 special
event triggers.
T1CON register is reset to 00h on a Power-on Reset or
a Brown-out Reset, which shuts off the timer and
leaves a 1:1 prescale. In all other RESETS, the register
is unaffected.
TABLE 5-2:
Address
REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Name
0Bh,8Bh, INTCON
10Bh,18Bh
0Ch
PIR1
Value on
all other
RESETS
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x 0000 000u
—
ADIF
—
—
SSPIF
CCP1IF
TMR2IF
TMR1IF 0000 0000 0000 0000
—
ADIE
—
—
SSPIE
CCP1IE
TMR2IE
TMR1IE 0000 0000 0000 0000
8Ch
PIE1
0Eh
TMR1L
Holding register for the Least Significant Byte of the 16-bit TMR1 Register
xxxx xxxx uuuu uuuu
0Fh
TMR1H
Holding register for the Most Significant Byte of the 16-bit TMR1 Register
xxxx xxxx uuuu uuuu
10h
T1CON
Legend:
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
x = unknown, u = unchanged, - = unimplemented, read as ‘0’. Shaded cells are not used by the Timer1 module.
DS39597C-page 32
© 2007 Microchip Technology Inc.
PIC16F72
6.0
TIMER2 MODULE
The Timer2 module timer has the following features:
•
•
•
•
•
•
•
8-bit timer (TMR2 register)
8-bit period register (PR2)
Readable and writable (both registers)
Software programmable prescaler (1:1, 1:4, 1:16)
Software programmable postscaler (1:1 to 1:16)
Interrupt on TMR2 match of PR2
SSP module optional use of TMR2 output to
generate clock shift
Timer2 has a control register, shown in Register 6-1.
Timer2 can be shut-off by clearing control bit TMR2ON
(T2CON<2>) to minimize power consumption.
Figure 6-1 is a simplified block diagram of the Timer2
module.
Additional information on timer modules is available in
the PIC™ Mid-Range MCU Reference Manual,
(DS33023).
6.1
Timer2 Operation
Timer2 can be used as the PWM time-base for PWM
mode of the CCP module.
The TMR2 register is readable and writable, and is
cleared on any device RESET.
The input clock (FOSC/4) has a prescale option of 1:1,
1:4
or
1:16,
selected
by
control
bits
T2CKPS1:T2CKPS0 (T2CON<1:0>).
The match output of TMR2 goes through a 4-bit
postscaler (which gives a 1:1 to 1:16 scaling inclusive)
to generate a TMR2 interrupt (latched in flag bit
TMR2IF, (PIR1<1>)).
6.2
Timer2 Prescaler and Postscaler
The prescaler and postscaler counters are cleared
when any of the following occurs:
• A write to the TMR2 register
• A write to the T2CON register
• Any device RESET (Power-on Reset, MCLR ,
WDT Reset, or Brown-out Reset)
TMR2 is not cleared when T2CON is written.
6.3
Timer2 Interrupt
The Timer2 module has an 8-bit period register, PR2.
Timer2 increments from 00h until it matches PR2 and
then resets to 00h on the next increment cycle. PR2 is
a readable and writable register. The PR2 register is
initialized to FFh upon RESET.
6.4
Output of TMR2
The output of TMR2 (before the postscaler) is fed to the
Synchronous Serial Port module, which optionally uses
it to generate a shift clock.
FIGURE 6-1:
Sets Flag
bit TMR2IF
TIMER2 BLOCK DIAGRAM
TMR2 (1)
Output
RESET
Postscaler
1:1 to 1:16
4
EQ
TMR2 reg
Comparator
Prescaler
1:1, 1:4, 1:16
FOSC/4
2
PR2 reg
Note 1: TMR2 register output can be software
selected by the SSP module as a baud clock.
© 2007 Microchip Technology Inc.
DS39597C-page 33
PIC16F72
REGISTER 6-1:
T2CON: TIMER2 CONTROL REGISTER (ADDRESS 12h)
U-0
—
R/W-0
R/W-0
TOUTPS3 TOUTPS2
R/W-0
R/W-0
TOUTPS1
R/W-0
R/W-0
R/W-0
TOUTPS0 TMR2ON T2CKPS1 T2CKPS0
bit 7
bit 0
bit 7
Unimplemented: Read as ‘0’
bit 6-3
TOUTPS3:TOUTPS0: Timer2 Output Postscale Select bits
0000 = 1:1 Postscale
0001 = 1:2 Postscale
0010 = 1:3 Postscale
•
•
•
1111 = 1:16 Postscale
bit 2
TMR2ON: Timer2 On bit
1 = Timer2 is on
0 = Timer2 is off
bit 1-0
T2CKPS1:T2CKPS0: Timer2 Clock Prescale Select bits
00 = Prescaler is 1
01 = Prescaler is 4
1x = Prescaler is 16
Legend:
TABLE 6-1:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER
Value on
all other
RESETS
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
0Bh,8Bh,
INTCON GIE
10Bh, 18Bh
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x 0000 000u
Address
Name
0Ch
PIR1
—
ADIF
—
—
SSPIF
CCP1IF
TMR2IF
TMR1IF -0-- 0000 0000 0000
8Ch
PIE1
—
ADIE
—
—
SSPIE
CCP1IE
TMR2IE
TMR1IE -0-- 0000 0000 0000
11h
TMR2
12h
T2CON
92h
PR2
Legend:
Timer2 Module Register
—
0000 0000 0000 0000
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
Timer2 Period Register
1111 1111 1111 1111
x = unknown, u = unchanged, - = unimplemented, read as ‘0’. Shaded cells are not used by the Timer2 module.
DS39597C-page 34
© 2007 Microchip Technology Inc.
PIC16F72
7.0
READING PROGRAM MEMORY
7.1
The FLASH Program Memory is readable during normal operation over the entire VDD range. It is indirectly
addressed through Special Function Registers (SFR).
Up to 14-bit wide numbers can be stored in memory for
use as calibration parameters, serial numbers, packed
7-bit ASCII, etc. Executing a program memory location
containing data that forms an invalid instruction results
in a NOP.
There are five SFRs used to read the program and
memory:
•
•
•
•
•
PMADR
The address registers can address up to a maximum of
8K words of program FLASH.
When selecting a program address value, the MSByte
of the address is written to the PMADRH register and
the LSByte is written to the PMADRL register. The
upper MSbits of PMADRH must always be clear.
7.2
PMCON1 Register
PMCON1 is the control register for memory accesses.
The control bit RD initiates read operations. This bit
cannot be cleared, only set, in software. It is cleared in
hardware at the completion of the read operation.
PMCON1
PMDATL
PMDATH
PMADRL
PMADRH
The program memory allows word reads. Program
memory access allows for checksum calculation and
reading calibration tables.
When interfacing to the program memory block, the
PMDATH:PMDATL registers form a two-byte word,
which holds the 14-bit data for reads. The
PMADRH:PMADRL registers form a two-byte word,
which holds the 13-bit address of the FLASH location
being accessed. This device has up to 2K words of
program FLASH, with an address range from 0h to
07FFh. The unused upper bits PMDATH<7:6> and
PMADRH<7:5> are not implemented and read as
zeros.
REGISTER 7-1:
PMCON1: PROGRAM MEMORY CONTROL REGISTER 1 (ADDRESS 18Ch)
R-1
U-0
U-0
U-0
U-0
U-0
U-0
R/S-0
reserved
—
—
—
—
—
—
RD
bit 7
bit 0
bit 7
Reserved: Read as ‘1’
bit 6-1
Unimplemented: Read as ‘0’
bit 0
RD: Read Control bit
1 = Initiates a FLASH read, RD is cleared in hardware. The RD bit can only be set (not cleared)
in software.
0 = Does not initiate a FLASH read
Legend:
W = Writable bit
U = Unimplemented bit, read as ‘0’
R = Readable bit
S = Settable bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
© 2007 Microchip Technology Inc.
DS39597C-page 35
PIC16F72
7.3
Reading the FLASH Program
Memory
7.4
To read a program memory location, the user must
write two bytes of the address to the PMADRL and
PMADRH registers and then set control bit, RD
(PMCON1<0>). Once the read control bit is set, the
program memory FLASH controller will use the second
instruction cycle after to read the data. This causes the
second instruction immediately following the “BSF
PMCON1,RD” instruction to be ignored. The data is
available in the very next cycle in the PMDATL and
PMDATH registers; therefore, it can be read as two
bytes in the following instructions. PMDATL and
PMDATH registers will hold this value until another
read, or until it is written to by the user (during a write
operation).
EXAMPLE 7-1:
BANKSEL
MOVLW
MOVWF
MOVLW
MOVWF
BANKSEL
BSF
NOP
NOP
BANKSEL PMDATL
MOVF
PMDATL, W
MOVF
PMDATH, W
Address
The FLASH program memory control can read anywhere within the program memory, whether or not the
program memory is code protected.
This does not compromise the code, because there is
no way to rewrite a portion of the program memory, or
leave contents of a program memory read in a register
while changing modes.
FLASH PROGRAM READ
PMADRH
MS_PROG_EE_ADDR
PMADRH
LS_PROG_EE_ADDR
PMADRL
PMCON1
PMCON1, RD
TABLE 7-1:
Operation During Code Protect
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Select Bank for PMADRH
MS Byte of Program Address to read
LS Byte of Program Address to read
Select Bank for PMCON1
EE Read
Any instructions here are ignored as program
memory is read in second cycle after BSF PMCON1,RD
First instruction after BSF PMCON1,RD executes normally
Select Bank for PMDATL
W = LS Byte of Program PMDATL
W = MS Byte of Program PMDATL
REGISTERS ASSOCIATED WITH PROGRAM FLASH
Name
Bit 7
Bit 6
10Dh
PMADRL
10Fh
PMADRH
10Ch
PMDATL
10Eh
PMDATH
—
—
18Ch
PMCON1
—(1)
—
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Address Register Low Byte
—
—
—
Value on
all other
RESETS
xxxx xxxx uuuu uuuu
Address Register High Byte
xxxx xxxx uuuu uuuu
Data Register Low Byte
xxxx xxxx uuuu uuuu
Data Register High Byte
—
Value on
POR, BOR
—
—
xxxx xxxx uuuu uuuu
—
—
RD
1--- ---0 1--- ---0
Legend: x = unknown, u = unchanged, r = reserved, - = unimplemented, read as '0'.
Shaded cells are not used during FLASH access.
Note 1: This bit always reads as a ‘1’.
DS39597C-page 36
© 2007 Microchip Technology Inc.
PIC16F72
8.0
CAPTURE/COMPARE/PWM
(CCP) MODULE
Additional information on the CCP module is available
in the PIC™ Mid-Range MCU Reference Manual,
(DS33023).
The CCP (Capture/Compare/PWM) module contains a
16-bit register that can operate as a:
TABLE 8-1:
• 16-bit capture register
• 16-bit compare register
• PWM master/slave duty cycle register.
Table 8-1 shows the timer resources of the CCP
Module modes.
CCP MODE - TIMER
RESOURCE
CCP Mode
Timer Resource
Capture
Compare
PWM
Timer1
Timer1
Timer2
Capture/Compare/PWM Register1 (CCPR1) is comprised of two 8-bit registers: CCPR1L (low byte) and
CCPR1H (high byte). The CCP1CON register controls
the operation of CCP1. All are readable and writable.
REGISTER 8-1:
CCPCON1: CAPTURE/COMPARE/PWM CONTROL REGISTER 1 (ADDRESS 17h)
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
CCPxX
CCPxY
CCPxM3
CCPxM2
CCPxM1
CCPxM0
bit 7
bit 0
bit 7-6
Unimplemented: Read as '0'
bit 5-4
CCPxX:CCPxY: PWM Least Significant bits
Capture mode:
Unused
Compare mode:
Unused
PWM mode:
These bits are the two LSbs of the PWM duty cycle. The eight MSbs are found in CCPRxL.
bit 3-0
CCPxM3:CCPxM0: CCPx Mode Select bits
0000 = Capture/Compare/PWM disabled (resets CCPx module)
0100 = Capture mode, every falling edge
0101 = Capture mode, every rising edge
0110 = Capture mode, every 4th rising edge
0111 = Capture mode, every 16th rising edge
1000 = Compare mode, set output on match (CCPxIF bit is set)
1001 = Compare mode, clear output on match (CCPxIF bit is set)
1010 = Compare mode, generate software interrupt on match (CCPxIF bit is set,
CCPx pin is unaffected)
1011 = Compare mode, trigger special event (CCPxIF bit is set, CCPx pin is unaffected);
CCP1 resets TMR1 and starts an A/D conversion (if A/D module is enabled)
11xx = PWM mode
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
x = Bit is unknown
DS39597C-page 37
PIC16F72
8.1
8.1.2
Capture Mode
In Capture mode, CCPR1H:CCPR1L captures the
16-bit value of the TMR1 register when an event occurs
on pin RC2/CCP1. An event is defined as:
•
•
•
•
Every falling edge
Every rising edge
Every 4th rising edge
Every 16th rising edge
8.1.1
CCP PIN CONFIGURATION
In Capture mode, the RC2/CCP1 pin should be
configured as an input by setting the TRISC<2> bit.
Note:
If the RC2/CCP1 is configured as an output, a write to the port can cause a capture
condition.
FIGURE 8-1:
CAPTURE MODE
OPERATION BLOCK
DIAGRAM
Prescaler
÷ 1, 4, 16
CCPR1H
and
edge detect
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep bit
CCP1IE (PIE1<2>) clear to avoid false interrupts and
should clear the flag bit CCP1IF, following any such
change in Operating mode.
8.1.4
CCP PRESCALER
There are four prescaler settings, specified by bits
CCP1M3:CCP1M0. Whenever the CCP module is
turned off, or the CCP module is not in Capture mode,
the prescaler counter is cleared. This means that any
RESET will clear the prescaler counter.
Switching from one capture prescaler to another may
generate an interrupt. Also, the prescaler counter will
not be cleared, therefore, the first capture may be from
a non-zero prescaler. Example 8-1 shows the recommended method for switching between capture prescalers. This example also clears the prescaler counter
and will not generate the “false” interrupt.
CCPR1L
CLRF
MOVLW
Capture
Enable
MOVWF
TMR1H
SOFTWARE INTERRUPT
EXAMPLE 8-1:
Set Flag bit CCP1IF
(PIR1<2>)
RC2/CCP1
pin
Timer1 must be running in Timer mode or Synchronized Counter mode for the CCP module to use the
capture feature. In Asynchronous Counter mode, the
capture operation may not work.
8.1.3
An event is selected by control bits CCP1M3:CCP1M0
(CCP1CON<3:0>). When a capture is made, the interrupt request flag bit CCP1IF (PIR1<2>) is set. It must
be cleared in software. If another capture occurs before
the value in register CCPR1 is read, the old captured
value is overwritten by the new captured value.
TIMER1 MODE SELECTION
TMR1L
CHANGING BETWEEN
CAPTURE PRESCALERS
CCP1CON
; Turn CCP module off
NEW_CAPT_PS ; Load the W reg with
; the new prescaler
; mode value and CCP ON
CCP1CON
; Load CCP1CON with
; this value
CCP1CON<3:0>
Q’s
DS39597C-page 38
© 2007 Microchip Technology Inc.
PIC16F72
8.2
8.2.1
Compare Mode
In Compare mode, the 16-bit CCPR1 register value is
constantly compared against the TMR1 register pair
value. When a match occurs, the RC2/CCP1 pin is:
• Driven High
• Driven Low
• Remains Unchanged
The action on the pin is based on the value of control
bits CCP1M3:CCP1M0 (CCP1CON<3:0>). At the
same time, interrupt flag bit CCP1IF is set.
The output may become inverted when the mode of the
module is changed from Compare/Clear on Match
(CCPxM<3:0> = ‘1001’) to Compare/Set on Match
(CCPxM<3:0> = ‘1000’). This may occur as a result of
any operation that selectively clears bit CCPxM0, such
as a BCF instruction.
When this condition occurs, the output becomes
inverted when the instruction is executed. It will remain
inverted for all following Compare operations, until the
module is reset.
FIGURE 8-2:
COMPARE MODE
OPERATION BLOCK
DIAGRAM
CCP PIN CONFIGURATION
The user must configure the RC2/CCP1 pin as an
output by clearing the TRISC<2> bit.
Note:
8.2.2
Clearing the CCP1CON register will force
the RC2/CCP1 compare output latch to the
default low level. This is not the data latch.
TIMER1 MODE SELECTION
Timer1 must be running in Timer mode or Synchronized Counter mode, if the CCP module is using the
compare feature. In Asynchronous Counter mode, the
compare operation may not work.
8.2.3
SOFTWARE INTERRUPT MODE
When generate software interrupt is chosen, the CCP1
pin is not affected. Only a CCP interrupt is generated (if
enabled).
8.2.4
SPECIAL EVENT TRIGGER
In this mode, an internal hardware trigger is generated
that may be used to initiate an action.
Special event trigger will:
The special event trigger output of CCP1 resets the
TMR1 register pair. This allows the CCPR1 register to
effectively be a 16-bit programmable period register for
Timer1.
• RESET Timer1, but not set interrupt flag bit TMR1IF
(PIR1<0>)
• Set bit GO/DONE (ADCON0<2>) bit, which starts an A/D
conversion
The special trigger output of CCP1 resets the TMR1
register pair, and starts an A/D conversion (if the A/D
module is enabled).
Note:
Special Event Trigger
Set Flag bit CCP1IF
(PIR1<2>)
The special event trigger from the CCP1
module will not set interrupt flag bit
TMR1IF (PIR1<0>).
CCPR1H CCPR1L
Q S Output
Logic
Match
RC2/CCP1
R
pin
TRISC<2>
Output Enable CCP1CON<3:0>
Mode Select
© 2007 Microchip Technology Inc.
Comparator
TMR1H
TMR1L
DS39597C-page 39
PIC16F72
TABLE 8-2:
REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, AND TIMER1
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
0Bh,8Bh
INTCON
10Bh,18Bh
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x 0000 000u
—
ADIF
—
—
SSPIF
CCP1IF
TMR2IF
TMR1IF -0-- 0000 0000 0000
—
ADIE
—
—
SSPIE
CCP1IE
TMR2IE
TMR1IE -0-- 0000 0000 0000
Address
0Ch
PIR1
8Ch
PIE1
87h
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
0Eh
TMR1L
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
xxxx xxxx uuuu uuuu
0Fh
TMR1H
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
xxxx xxxx uuuu uuuu
10h
T1CON
15h
CCPR1L
Capture/Compare/PWM Register1 (LSB)
xxxx xxxx uuuu uuuu
16h
CCPR1H
Capture/Compare/PWM Register1 (MSB)
xxxx xxxx uuuu uuuu
17h
CCP1CON
Legend:
—
—
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
CCP1X
CCP1Y
CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
x = unknown, u = unchanged, - = unimplemented, read as ‘0’. Shaded cells are not used by Capture and Timer1.
DS39597C-page 40
© 2007 Microchip Technology Inc.
PIC16F72
8.3
8.3.1
PWM Mode
In Pulse Width Modulation (PWM) mode, the CCP1 pin
produces up to a 10-bit resolution PWM output. Since
the CCP1 pin is multiplexed with the PORTC data latch,
the TRISC<2> bit must be cleared to make the CCP1
pin an output.
Note:
Clearing the CCP1CON register will force
the CCP1 PWM output latch to the default
low level. This is not the PORTC I/O data
latch.
PWM PERIOD
The PWM period is specified by writing to the PR2 register. The PWM period can be calculated using the
formula in Equation 8-1.
EQUATION 8-1:
PWM PERIOD
PWM period = [(PR2) + 1] • 4 • TOSC •
(TMR2 prescale value)
PWM frequency is defined as 1 / [PWM period].
Figure 8-3 shows a simplified block diagram of the
CCP module in PWM mode.
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
For a step by step procedure on how to set up the CCP
module for PWM operation, see Section 8.3.3.
• TMR2 is cleared
• The CCP1 pin is set (exception: if PWM duty
cycle = 0%, the CCP1 pin will not be set)
• The PWM duty cycle is latched from CCPR1L into
CCPR1H
FIGURE 8-3:
SIMPLIFIED PWM BLOCK
DIAGRAM
CCP1CON<5:4>
Duty Cycle Registers
Note:
CCPR1L
The Timer2 postscaler (see Section 6.0) is
not used in the determination of the PWM
frequency. The postscaler could be used to
have a servo update rate at a different
frequency than the PWM output.
CCPR1H (Slave)
8.3.2
R
Comparator
Q
RC2/CCP1
TMR2
(Note 1)
S
TRISC<2>
Comparator
Clear Timer,
CCP1 pin and
latch D.C.
PR2
PWM DUTY CYCLE
The PWM duty cycle is specified by writing to the
CCPR1L register and to the CCP1CON<5:4> bits. Up
to 10-bit resolution is available: the CCPR1L contains
the eight MSbs and the CCP1CON<5:4> contains the
two LSbs. This 10-bit value is represented by
CCPR1L:CCP1CON<5:4>. Equation 8-2 is used to
calculate the PWM duty cycle in time.
EQUATION 8-2:
PWM DUTY CYCLE
Note 1: 8-bit timer is concatenated with 2-bit internal Q clock
or 2 bits of the prescaler to create 10-bit time-base.
PWM duty cycle = (CCPR1L:CCP1CON<5:4>) •
TOSC • (TMR2 prescale value)
A PWM output (Figure 8-4) has a time-base (period)
and a time that the output stays high (duty cycle). The
frequency of the PWM is the inverse of the period
(1/period).
CCPR1L and CCP1CON<5:4> can be written to at any
time, but the duty cycle value is not latched into
CCPR1H until after a match between PR2 and TMR2
occurs (i.e., the period is complete). In PWM mode,
CCPR1H is a read only register.
FIGURE 8-4:
PWM OUTPUT
Period
The CCPR1H register and a 2-bit internal latch are
used to double buffer the PWM duty cycle. This double
buffering is essential for glitchless PWM operation.
When the CCPR1H and 2-bit latch match TMR2,
concatenated with an internal 2-bit Q clock or 2 bits of
the TMR2 prescaler, the CCP1 pin is cleared.
Duty Cycle
TMR2 = PR2
TMR2 = Duty Cycle
TMR2 = PR2
© 2007 Microchip Technology Inc.
DS39597C-page 41
PIC16F72
Maximum PWM resolution (bits) for a given PWM
frequency is calculated using Equation 8-3.
EQUATION 8-3:
PWM MAX RESOLUTION
PWM Maximum Resolution =
FOSC
log ( FPWM )
log(2)
8.3.3
The following steps should be taken when configuring
the CCP module for PWM operation:
1.
2.
bits
3.
Note:
If the PWM duty cycle value is longer than
the PWM period, the CCP1 pin will not be
cleared.
For a sample PWM period and duty cycle calculation,
see the PIC™ Mid-Range MCU Reference Manual
(DS33023).
TABLE 8-3:
SET-UP FOR PWM OPERATION
4.
5.
Set the PWM period by writing to the PR2 register.
Set the PWM duty cycle by writing to the
CCPR1L register and CCP1CON<5:4> bits.
Make the CCP1 pin an output by clearing the
TRISC<2> bit.
Set the TMR2 prescale value and enable Timer2
by writing to T2CON.
Configure the CCP1 module for PWM operation.
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 20 MHz
PWM Frequency
1.22 kHz 4.88 kHz 19.53 kHz 78.12 kHz 156.3 kHz 208.3 kHz
Timer Prescaler (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
TABLE 8-4:
16
0xFF
10
4
0xFF
10
1
0xFF
10
1
0x3F
8
1
0x1F
7
1
0x17
5.5
REGISTERS ASSOCIATED WITH PWM AND TIMER2
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
0Bh,8Bh
INTCON
10Bh,18Bh
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x 0000 000u
—
ADIF
—
—
SSPIF
CCP1IF
TMR2IF
TMR1IF -0-- 0000 0000 0000
—
ADIE
—
—
SSPIE
CCP1IE
TMR2IE
TMR1IE -0-- 0000 0000 0000
Address
0Ch
PIR1
8Ch
PIE1
87h
TRISC
11h
92h
12h
T2CON
15h
CCPR1L
Capture/Compare/PWM Register1 (LSB)
16h
CCPR1H
Capture/Compare/PWM Register1 (MSB)
17h
CCP1CON
Legend:
PORTC Data Direction Register
1111 1111 1111 1111
TMR2
Timer2 Module Register
0000 0000 0000 0000
PR2
Timer2 Module Period Register
1111 1111 1111 1111
—
—
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
—
CCP1X
CCP1Y
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
x = unknown, u = unchanged, - = unimplemented, read as ‘0’. Shaded cells are not used by PWM and Timer2.
DS39597C-page 42
© 2007 Microchip Technology Inc.
PIC16F72
9.0
9.1
SYNCHRONOUS SERIAL PORT
(SSP) MODULE
SSP Module Overview
The Synchronous Serial Port (SSP) module is a serial
interface useful for communicating with other peripheral or microcontroller devices. These peripheral
devices may be Serial EEPROMs, shift registers, display drivers, A/D converters, etc. The SSP module can
operate in one of two modes:
9.2
SPI Mode
This section contains register definitions
operational characteristics of the SPI module.
and
SPI mode allows 8 bits of data to be synchronously
transmitted and received simultaneously. To accomplish
communication, typically three pins are used:
• Serial Data Out (SDO)
• Serial Data In (SDI)
• Serial Clock (SCK)
RC5/SDO
RC4/SDI/SDA
RC3/SCK/SCL
• Serial Peripheral Interface (SPI)
• Inter-Integrated Circuit (I2C)
Additionally, a fourth pin may be used when in a Slave
mode of operation:
An overview of I2C operations and additional information on the SSP module can be found in the PIC™
Mid-Range
MCU
Family
Reference Manual
(DS33023).
• Slave Select (SS)
Refer to Application Note AN578, “Use of the SSP
Module in the I 2C Multi-Master Environment.”
RA5/AN4/SS
When initializing the SPI, several options need to be
specified. This is done by programming the appropriate
control bits in the SSPCON register (SSPCON<5:0>)
and SSPSTAT<7:6>. These control bits allow the
following to be specified:
•
•
•
•
Master mode (SCK is the clock output)
Slave mode (SCK is the clock input)
Clock Polarity (IDLE state of SCK)
Clock edge (output data on rising/falling edge of
SCK)
• Clock Rate (Master mode only)
• Slave Select mode (Slave mode only)
© 2007 Microchip Technology Inc.
DS39597C-page 43
PIC16F72
REGISTER 9-1:
SSPSTAT: SYNCHRONOUS SERIAL PORT STATUS REGISTER (ADDRESS 94h)
R/W-0
R/W-0
R-0
R-0
R-0
R-0
R-0
R-0
SMP
CKE
D/A
P
S
R/W
UA
BF
bit 7
bit 0
bit 7
SMP: SPI Data Input Sample Phase bits
SPI Master mode:
1 = Input data sampled at end of data output time
0 = Input data sampled at middle of data output time (Microwire®)
SPI Slave mode:
SMP must be cleared when SPI is used in Slave mode
I2 C mode:
This bit must be maintained clear
bit 6
CKE: SPI Clock Edge Select bits (Figure 9-2, Figure 9-3, and Figure 9-4)
SPI mode, CKP = 0:
1 = Data transmitted on rising edge of SCK (Microwire alternate)
0 = Data transmitted on falling edge of SCK
SPI mode, CKP = 1:
1 = Data transmitted on falling edge of SCK (Microwire default)
0 = Data transmitted on rising edge of SCK
I2 C mode:
This bit must be maintained clear
bit 5
D/A: Data/Address bit (I2C mode only)
1 = Indicates that the last byte received or transmitted was data
0 = Indicates that the last byte received or transmitted was address
bit 4
P: STOP bit (I2C mode only) – This bit is cleared when the SSP module is disabled, or when
the START bit is detected last. SSPEN is cleared.
1 = Indicates that a STOP bit has been detected last (this bit is ‘0’ on RESET)
0 = STOP bit was not detected last
bit 3
S: START bit (I2C mode only) – This bit is cleared when the SSP module is disabled, or when
the STOP bit is detected last. SSPEN is cleared.
1 = Indicates that a START bit has been detected last (this bit is ‘0’ on RESET)
0 = START bit was not detected last
bit 2
R/W: Read/Write Information bit (I2C mode only) – This bit holds the R/W bit information following the last address match. This bit is only valid from the address match to the next START bit,
STOP bit, or ACK bit.
1 = Read
0 = Write
bit 1
UA: Update Address bit (10-bit I2C mode only)
1 = Indicates that the user needs to update the address in the SSPADD register
0 = Address does not need to be updated
bit 0
BF: Buffer Full Status bit
Receive (SPI and I2 C modes):
1 = Receive complete, SSPBUF is full
0 = Receive not complete, SSPBUF is empty
Transmit (I2 C mode only):
1 = Transmit in progress, SSPBUF is full
0 = Transmit complete, SSPBUF is empty
Legend:
R = Readable bit
- n = Value at POR
DS39597C-page 44
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
© 2007 Microchip Technology Inc.
PIC16F72
REGISTER 9-2:
SSPCON: SYNC SERIAL PORT CONTROL REGISTER (ADDRESS 14h)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
bit 7
bit 0
bit 7
WCOL: Write Collision Detect bit
1 = The SSPBUF register is written while it is still transmitting the previous word (must be
cleared in software)
0 = No collision
bit 6
SSPOV: Receive Overflow Indicator bit
In SPI mode:
1 = A new byte is received while the SSPBUF register is still holding the previous data. In case
of overflow, the data in SSPSR is lost. Overflow can only occur in Slave mode. The user
must read the SSPBUF, even if only transmitting data, to avoid setting overflow. In Master
mode, the overflow bit is not set since each new reception (and transmission) is initiated
by writing to the SSPBUF register.
0 = No overflow
In I2 C mode:
1 = A byte is received while the SSPBUF register is still holding the previous byte. SSPOV
is a "don’t care" in Transmit mode. SSPOV must be cleared in software in either mode.
0 = No overflow
bit 5
SSPEN: Synchronous Serial Port Enable bit
In SPI mode:
1 = Enables serial port and configures SCK, SDO, and SDI as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
In I2 C mode:
1 = Enables the serial port and configures the SDA and SCL pins as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
In both modes, when enabled, these pins must be properly configured as input or output.
bit 4
CKP: Clock Polarity Select bit
In SPI mode:
1 = IDLE state for clock is a high level (Microwire® default)
0 = IDLE state for clock is a low level (Microwire alternate)
In I2 C mode:
SCK release control
1 = Enable clock
0 = Holds clock low (clock stretch - used to ensure data setup time)
bit 3-0
SSPM<3:0>: Synchronous Serial Port Mode Select bits
0000 = SPI Master mode, clock = FOSC/4
0001 = SPI Master mode, clock = FOSC/16
0010 = SPI Master mode, clock = FOSC/64
0011 = SPI Master mode, clock = TMR2 output/2
0100 = SPI Slave mode, clock = SCK pin. SS pin control enabled.
0101 = SPI Slave mode, clock = SCK pin. SS pin control disabled. SS can be used as I/O pin.
0110 = I2C Slave mode, 7-bit address
0111 = I2C Slave mode, 10-bit address
1011 = I2C firmware controlled Master mode (Slave IDLE)
1110 = I2C Slave mode, 7-bit address with START and STOP bit interrupts enabled
1111 = I2C Slave mode, 10-bit address with START and STOP bit interrupts enabled
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
x = Bit is unknown
DS39597C-page 45
PIC16F72
FIGURE 9-1:
SSP BLOCK DIAGRAM
(SPI MODE)
To enable the serial port, SSP enable bit, SSPEN
(SSPCON<5>) must be set. To reset or reconfigure SPI
mode, clear bit SSPEN, re-initialize the SSPCON register, and then set bit SSPEN. This configures the SDI,
SDO, SCK, and SS pins as serial port pins. For the pins
to behave as the serial port function, they must have
their data direction bits (in the TRISC register)
appropriately programmed. That is:
Internal
Data Bus
Read
Write
SSPBUF reg
• SDI must have TRISC<4> set
• SDO must have TRISC<5> cleared
• SCK (Master mode) must have TRISC<3>
cleared
• SCK (Slave mode) must have TRISC<3> set
• SS must have TRISA<5> set and ADCON must
be configured such that RA5 is a digital I/O
SSPSR reg
RC4/SDI/SDA
Shift
Clock
bit0
RC5/SDO
.
SS Control
Enable
RA5/AN4/SS
Note 1: When the SPI is in Slave mode with SS pin
control enabled (SSPCON<3:0> = 0100),
the SPI module will reset if the SS pin is
set to VDD.
Edge
Select
2
Clock Select
SSPM3:SSPM0
4
Edge
Select
RC3/SCK/
SCL
2: If the SPI is used in Slave mode with
CKE = ‘1’, then the SS pin control must be
enabled.
TMR2 Output
2
Prescaler TCY
4, 16, 64
TRISC<3>
TABLE 9-1:
REGISTERS ASSOCIATED WITH SPI OPERATION
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
0Bh,8Bh
INTCON
10Bh,18Bh
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x 0000 000u
Address
0Ch
PIR1
—
ADIF
—
—
SSPIF
CCP1IF TMR2IF TMR1IF -0-- 0000 0000 0000
8Ch
PIE1
—
ADIE
—
—
SSPIE
CCP1IE TMR2IE TMR1IE -0-- 0000 0000 0000
87h
TRISC
PORTC Data Direction Register
1111 1111 1111 1111
13h
SSPBUF
Synchronous Serial Port Receive Buffer/Transmit Register
xxxx xxxx uuuu uuuu
14h
SSPCON
WCOL SSPOV SSPEN
85h
TRISA
—
—
94h
SSPSTAT
—
—
CKP
SSPM3 SSPM2
SSPM1
SSPM0 0000 0000 0000 0000
PORTA Data Direction Register
D/A
P
S
R/W
--11 1111 --11 1111
UA
BF
--00 0000 --00 0000
Legend: x = unknown, u = unchanged, - = unimplemented, read as ‘0’. Shaded cells are not used by the SSP in SPI mode.
DS39597C-page 46
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 9-2:
SPI MODE TIMING, MASTER MODE
SCK (CKP = 0,
CKE = 0)
SCK (CKP = 0,
CKE = 1)
SCK (CKP = 1,
CKE = 0)
SCK (CKP = 1,
CKE = 1)
bit6
bit7
SDO
bit5
bit2
bit3
bit4
bit1
bit0
SDI (SMP = 0)
bit7
bit0
SDI (SMP = 1)
bit7
bit0
SSPIF
FIGURE 9-3:
SPI MODE TIMING (SLAVE MODE WITH CKE = 0)
SS (optional)
SCK (CKP = 0)
SCK (CKP = 1)
bit7
SDO
bit6
bit5
bit2
bit3
bit4
bit1
bit0
SDI (SMP = 0)
bit7
bit0
SSPIF
FIGURE 9-4:
SPI MODE TIMING (SLAVE MODE WITH CKE = 1)
SS
SCK (CKP = 0)
SCK (CKP = 1)
SDO
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
SDI (SMP = 0)
bit7
bit0
SSPIF
© 2007 Microchip Technology Inc.
DS39597C-page 47
PIC16F72
9.3
SSP I 2C Mode Operation
The SSP module in I 2C mode fully implements all slave
functions, except general call support and provides
interrupts on START and STOP bits in hardware to
facilitate firmware implementations of the master functions. The SSP module implements the Standard mode
specifications, as well as 7-bit and 10-bit addressing.
Two pins are used for data transfer. These are the RC3/
SCK/SCL pin, which is the clock (SCL), and the RC4/
SDI/SDA pin, which is the data (SDA). The user must
configure these pins as inputs or outputs through the
TRISC<4:3> bits.
The SSP module functions are enabled by setting SSP
Enable bit SSPEN (SSPCON<5>).
FIGURE 9-5:
SSP BLOCK DIAGRAM
(I2C MODE)
Internal
Data Bus
Read
Write
Selection of any I 2C mode, with the SSPEN bit set,
forces the SCL and SDA pins to be open drain, provided these pins are programmed to inputs by setting
the appropriate TRISC bits.
Additional information on SSP I2C operation may be
found in the PIC™ Mid-Range MCU Reference Manual
(DS33023).
9.3.1
In Slave mode, the SCL and SDA pins must be configured as inputs (TRISC<4:3> set). The SSP module will
override the input state with the output data when
required (slave-transmitter).
When an address is matched or the data transfer after
an address match is received, the hardware automatically will generate the Acknowledge (ACK) pulse, and
then load the SSPBUF register with the received value
currently in the SSPSR register.
Either or both of the following conditions will cause the
SSP module not to give this ACK pulse.
a)
SSPBUF Reg
RC3/SCK/SCL
b)
Shift
Clock
SSPSR Reg
RC4/
SDI/
SDA
MSb
LSb
Match Detect
Addr Match
SSPADD Reg
START and
STOP Bit Detect
Set, RESET
S, P Bits
(SSPSTAT Reg)
The SSP module has five registers for I2C operation:
•
•
•
•
SSP Control Register (SSPCON)
SSP Status Register (SSPSTAT)
Serial Receive/Transmit Buffer (SSPBUF)
SSP Shift Register (SSPSR) - Not directly
accessible
• SSP Address Register (SSPADD)
The SSPCON register allows control of the I 2C operation. Four mode selection bits (SSPCON<3:0>) allow
one of the following I 2C modes to be selected:
• I 2C Slave mode (7-bit address)
• I 2C Slave mode (10-bit address)
• I 2C Slave mode (7-bit address), with START and
STOP bit interrupts enabled
• I 2C Slave mode (10-bit address), with START and
STOP bit interrupts enabled
• I 2C Firmware controlled Master operation, Slave
is IDLE
DS39597C-page 48
SLAVE MODE
The buffer full bit BF (SSPSTAT<0>) was set
before the transfer was received.
The overflow bit SSPOV (SSPCON<6>) was set
before the transfer was received.
In this case, the SSPSR register value is not loaded
into the SSPBUF, but bit SSPIF (PIR1<3>) is set.
Table 9-2 shows what happens when a data transfer
byte is received, given the status of bits BF and
SSPOV. The shaded cells show the condition where
user software did not properly clear the overflow condition. Flag bit BF is cleared by reading the SSPBUF
register while bit SSPOV is cleared through software.
The SCL clock input must have a minimum high and
low for proper operation. The high and low times of the
I2C specification, as well as the requirement of the SSP
module are shown in timing parameter #100 and
parameter #101.
9.3.1.1
Addressing
Once the SSP module has been enabled, it waits for a
START condition to occur. Following the START condition, the eight bits are shifted into the SSPSR register.
All incoming bits are sampled with the rising edge of the
clock (SCL) line. The value of register SSPSR<7:1> is
compared to the value of the SSPADD register. The
address is compared on the falling edge of the eighth
clock (SCL) pulse. If the addresses match, and the BF
and SSPOV bits are clear, the following events occur:
a)
b)
c)
d)
The SSPSR register value is loaded into the
SSPBUF register.
The buffer full bit, BF is set.
An ACK pulse is generated.
SSP interrupt flag bit, SSPIF (PIR1<3>) is set
(interrupt is generated, if enabled) - on the falling
edge of the ninth SCL pulse.
© 2007 Microchip Technology Inc.
PIC16F72
In 10-bit Address mode, two address bytes need to be
received by the slave device. The five Most Significant
bits (MSbs) of the first address byte specify if this is a
10-bit address. Bit R/W (SSPSTAT<2>) must specify a
write so the slave device will receive the second
address byte. For a 10-bit address the first byte would
equal ‘1111 0 A9 A8 0’, where A9 and A8 are the
two MSbs of the address.
The sequence of events for 10-bit address is as
follows, with steps 7- 9 for slave-transmitter:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Receive first (high) byte of address (bits SSPIF,
BF, and bit UA (SSPSTAT<1>) are set).
Update the SSPADD register with second (low)
byte of address (clears bit UA and releases the
SCL line).
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
Receive second (low) byte of address (bits
SSPIF, BF, and UA are set).
Update the SSPADD register with the first (high)
byte of Address, if match releases SCL line, this
will clear bit UA.
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
Receive Repeated START condition.
Receive first (high) byte of address (bits SSPIF
and BF are set).
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
9.3.1.2
9.3.1.3
Transmission
When the R/W bit of the incoming address byte is set
and an address match occurs, the R/W bit of the
SSPSTAT register is set. The received address is
loaded into the SSPBUF register. The ACK pulse will
be sent on the ninth bit, and pin RC3/SCK/SCL is held
low. The transmit data must be loaded into the
SSPBUF register, which also loads the SSPSR register. Then pin RC3/SCK/SCL should be enabled by setting bit CKP (SSPCON<4>). The master device must
monitor the SCL pin prior to asserting another clock
pulse. The slave devices may be holding off the master
device by stretching the clock. The eight data bits are
shifted out on the falling edge of the SCL input. This
ensures that the SDA signal is valid during the SCL
high time (Figure 9-7).
An SSP interrupt is generated for each data transfer
byte. Flag bit SSPIF must be cleared in software and
the SSPSTAT register is used to determine the status
of the byte. Flag bit SSPIF is set on the falling edge of
the ninth clock pulse.
As a slave-transmitter, the ACK pulse from the masterreceiver is latched on the rising edge of the ninth SCL
input pulse. If the SDA line was high (not ACK), then
the data transfer is complete. When the ACK is latched
by the slave device, the slave logic is reset (resets
SSPSTAT register) and the slave device then monitors
for another occurrence of the START bit. If the SDA line
was low (ACK), the transmit data must be loaded into
the SSPBUF register, which also loads the SSPSR register. Then, pin RC3/SCK/SCL should be enabled by
setting bit CKP.
Reception
When the R/W bit of the address byte is clear and an
address match occurs, the R/W bit of the SSPSTAT
register is cleared. The received address is loaded into
the SSPBUF register.
When the address byte overflow condition exists, then
a no Acknowledge (ACK) pulse is given. An overflow
condition is indicated if either bit BF (SSPSTAT<0>) is
set, or bit SSPOV (SSPCON<6>) is set.
An SSP interrupt is generated for each data transfer
byte. Flag bit SSPIF (PIR1<3>) must be cleared in software. The SSPSTAT register is used to determine the
status of the byte.
TABLE 9-2:
DATA TRANSFER RECEIVED BYTE ACTIONS
Status Bits as Data
Transfer is Received
Generate ACK Pulse
Set bit SSPIF
(SSP Interrupt occurs if enabled)
BF
SSPOV
SSPSR → SSPBUF
0
0
Yes
Yes
Yes
1
0
No
No
Yes
1
1
No
No
Yes
0
1
No
No
Yes
Note 1: Shaded cells show the conditions where the user software did not properly clear the overflow condition.
© 2007 Microchip Technology Inc.
DS39597C-page 49
PIC16F72
I 2C WAVEFORMS FOR RECEPTION (7-BIT ADDRESS)
FIGURE 9-6:
Receiving Address R/W = 0
Receiving Data
Receiving Data
ACK
ACK
ACK
A7 A6 A5 A4 A3 A2 A1
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
SDA
SCL
1
S
2
3
4
5
6
7
9
8
1
2
SSPIF (PIR1<3>)
3
4
5
6
7
8
9
1
2
3
5
4
8
7
6
9
Cleared in software
BF (SSPSTAT<0>)
P
Bus Master
terminates
transfer
SSPBUF register is read
SSPOV (SSPCON<6>)
Bit SSPOV is set because the SSPBUF register is still full.
ACK is not sent.
I 2C WAVEFORMS FOR TRANSMISSION (7-BIT ADDRESS)
FIGURE 9-7:
Receiving Address
SDA
SCL
A7
S
A6
1
2
Data is
sampled
SSPIF (PIR1<3>)
R/W = 1
A5
A4
A3
A2
A1
3
4
5
6
7
8
9
ACK
Transmitting Data
ACK
D7
1
SCL held low
while CPU
responds to SSPIF
D6
D5
D4
D3
D2
D1
D0
2
3
4
5
6
7
8
9
P
Cleared in software
BF (SSPSTAT<0>)
SSPBUF is written in software
From SSP Interrupt
Service Routine
CKP (SSPCON<4>)
Set bit after writing to SSPBUF
(the SSPBUF must be written to
before the CKP bit can be set)
DS39597C-page 50
© 2007 Microchip Technology Inc.
PIC16F72
9.3.2
MASTER MODE OPERATION
9.3.3
Master mode operation is supported in firmware using
interrupt generation on the detection of the START and
STOP conditions. The STOP (P) and START (S) bits
are cleared from a RESET or when the SSP module is
disabled. The STOP (P) and START (S) bits will toggle,
based on the START and STOP conditions. Control of
the I 2C bus may be taken when the P bit is set, or the
bus is IDLE and both the S and P bits are clear.
MULTI-MASTER MODE OPERATION
In Multi-Master mode operation, the interrupt generation on the detection of the START and STOP conditions allows the determination of when the bus is free.
The STOP (P) and START (S) bits are cleared from a
RESET or when the SSP module is disabled. The
STOP (P) and START (S) bits will toggle, based on the
START and STOP conditions. Control of the I 2C bus
may be taken when bit P (SSPSTAT<4>) is set, or the
bus is IDLE and both the S and P bits clear. When the
bus is busy, enabling the SSP interrupt will generate
the interrupt when the STOP condition occurs.
In Master mode operation, the SCL and SDA lines are
manipulated in firmware by clearing the corresponding
TRISC<4:3> bit(s). The output level is always low, irrespective of the value(s) in PORTC<4:3>. So, when
transmitting data, a ‘1’ data bit must have the
TRISC<4> bit set (input) and a ‘0’ data bit must have
the TRISC<4> bit cleared (output). The same scenario
is true for the SCL line with the TRISC<3> bit.
In Multi-Master mode operation, the SDA line must be
monitored to see if the signal level is the expected output level. This check only needs to be done when a
high level is output. If a high level is expected and a low
level is present, the device needs to release the SDA
and SCL lines (set TRISC<4:3>). There are two stages
where this arbitration can be lost:
The following events will cause the SSP Interrupt Flag
bit, SSPIF, to be set (SSP Interrupt if enabled):
• Address Transfer
• Data Transfer
• START condition
• STOP condition
• Data transfer byte transmitted/received
When the slave logic is enabled, the Slave device continues to receive. If arbitration was lost during the
address transfer stage, communication to the device
may be in progress. If addressed, an ACK pulse will be
generated. If arbitration was lost during the data transfer stage, the device will need to retransfer the data at
a later time.
Master mode operation can be done with either the
Slave mode IDLE (SSPM3:SSPM0 = 1011), or with the
Slave mode active. When both Master mode operation
and Slave modes are used, the software needs to
differentiate the source(s) of the interrupt.
For more information on Master mode operation, see
AN554 - Software Implementation of I2C Bus Master.
For more information on Multi-Master mode operation,
see AN578 - Use of the SSP Module in the I2C
Multi-Master Environment.
REGISTERS ASSOCIATED WITH I2C OPERATION
TABLE 9-3:
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
RESETS
0Bh, 8Bh,
10Bh,18Bh
INTCON
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x
0000 000u
0Ch
PIR1
—
ADIF
—
—
SSPIF CCP1IF TMR2IF TMR1IF
-0-- 0000
0000 0000
8Ch
PIE1
—
ADIE
—
—
SSPIE CCP1IE TMR2IE TMR1IE
-0-- 0000
0000 0000
13h
SSPBUF Synchronous Serial Port Receive Buffer/Transmit Register
xxxx xxxx
uuuu uuuu
93h
SSPADD Synchronous Serial Port (I2C mode) Address Register
0000 0000
0000 0000
14h
SSPCON
WCOL
SSPOV
SSPEN
CKP
0000 0000
0000 0000
94h
SSPSTAT
SMP(1)
CKE(1)
D/A
P
0000 0000
0000 0000
87h
TRISC
1111 1111
1111 1111
SSPM3 SSPM2 SSPM1 SSPM0
S
R/W
PORTC Data Direction Register
UA
BF
Legend: x = unknown, u = unchanged, - = unimplemented locations read as ‘0’.
Shaded cells are not used by SSP module in SPI mode.
Note 1: Maintain these bits clear in I2C mode.
© 2007 Microchip Technology Inc.
DS39597C-page 51
PIC16F72
NOTES:
DS39597C-page 52
© 2007 Microchip Technology Inc.
PIC16F72
10.0
ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
The A/D module has three registers:
• A/D Result Register
• A/D Control Register 0
• A/D Control Register 1
The analog-to-digital (A/D) converter module has five
inputs for the PIC16F72.
A device RESET forces all registers to their RESET
state. This forces the A/D module to be turned off and
any conversion is aborted.
The A/D allows conversion of an analog input signal to
a corresponding 8-bit digital number. The output of the
sample and hold is the input into the converter, which
generates the result via successive approximation. The
analog reference voltage is software selectable to
either the device’s positive supply voltage (VDD) or the
voltage level on the RA3/AN3/VREF pin.
The ADCON0 register, shown in Register 10-1, controls the operation of the A/D module. The ADCON1
register, shown in Register 10-2, configures the functions of the port pins. The port pins can be configured
as analog inputs (RA3 can also be a voltage reference)
or a digital I/O.
The A/D converter has a unique feature of being able
to operate while the device is in SLEEP mode. To operate in SLEEP, the A/D conversion clock must be
derived from the A/D’s internal RC oscillator.
REGISTER 10-1:
ADRES
ADCON0
ADCON1
For more information on use of the A/D Converter, see
AN546 - Use of A/D Converter, or refer to the PIC™
Mid-Range
MCU Family
Reference Manual
(DS33023).
ADCON0: A/D CONTROL REGISTER 0 (ADDRESS 1Fh)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
U-0
R/W-0
ADCS1
ADCS0
CHS2
CHS1
CHS0
GO/DONE
—
ADON
bit 7
bit 0
bit 7-6
ADCS<1:0>: A/D Conversion Clock Select bits
00 = FOSC/2
01 = FOSC/8
10 = FOSC/32
11 = FRC (clock derived from the internal A/D module RC oscillator)
bit 5-3
CHS<2:0>: Analog Channel Select bits
000 = Channel 0, (RA0/AN0)
001 = Channel 1, (RA1/AN1)
010 = Channel 2, (RA2/AN2)
011 = Channel 3, (RA3/AN3)
100 = Channel 4, (RA5/AN4)
bit 2
GO/DONE: A/D Conversion Status bit
If ADON = 1:
1 = A/D conversion in progress (setting this bit starts the A/D conversion)
0 = A/D conversion not in progress (this bit is automatically cleared by hardware when the A/D
conversion is complete)
bit 1
Unimplemented: Read as ‘0’
bit 0
ADON: A/D On bit
1 = A/D converter module is operating
0 = A/D converter module is shut-off and consumes no operating current
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
x = Bit is unknown
DS39597C-page 53
PIC16F72
REGISTER 10-2:
ADCON1: A/D CONTROL REGISTER 1 (ADDRESS 9Fh)
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
—
—
—
—
—
PCFG2
PCFG1
PCFG0
bit 7
bit 0
bit 7-3
Unimplemented: Read as ‘0’
bit 2-0
PCFG<2:0>: A/D Port Configuration Control bits
PCFG2:PCFG0
RA0
RA1
RA2
RA5
RA3
VREF
000
001
010
011
100
101
11x
A
A
A
A
A
A
D
A
A
A
A
A
A
D
A
A
A
A
D
D
D
A
A
A
A
D
D
D
A
VREF
A
VREF
A
VREF
D
VDD
RA3
VDD
RA3
VDD
RA3
VDD
A = Analog input
D = Digital I/O
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
The ADRES register contains the result of the A/D conversion. When the A/D conversion is complete, the
result is loaded into the ADRES register, the GO/DONE
bit (ADCON0<2>) is cleared, and A/D interrupt flag bit
ADIF is set. The block diagram of the A/D module is
shown in Figure 10-1.
The following steps should be followed for doing an
A/D conversion:
1.
The value in the ADRES register is not modified for a
Power-on Reset. The ADRES register will contain
unknown data after a Power-on Reset.
After the A/D module has been configured as desired,
the selected channel must be acquired before the conversion is started. The analog input channels must
have their corresponding TRIS bits selected as an
input. To determine acquisition time, see Section 10.1.
After this acquisition time has elapsed, the A/D
conversion can be started.
x = Bit is unknown
2.
3.
4.
5.
Configure the A/D module:
• Configure analog pins/voltage reference and
digital I/O (ADCON1)
• Select A/D input channel (ADCON0)
• Select A/D conversion clock (ADCON0)
• Turn on A/D module (ADCON0)
Configure A/D interrupt (if desired):
• Clear ADIF bit
• Set ADIE bit
• Set GIE bit
Wait the required acquisition time.
Start conversion:
• Set GO/DONE bit (ADCON0)
Wait for A/D conversion to complete, by either:
• Polling for the GO/DONE bit to be cleared
OR
6.
7.
DS39597C-page 54
• Waiting for the A/D interrupt
Read A/D Result register (ADRES), clear bit
ADIF if required.
For next conversion, go to step 1 or step 2 as
required. The A/D conversion time per bit is
defined as TAD. A minimum wait of 2 TAD is
required before the next acquisition starts.
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 10-1:
A/D BLOCK DIAGRAM
CHS2:CHS0
100
RA5/AN4
VAIN
011
(Input Voltage)
RA3/AN3/VREF
010
RA2/AN2
A/D
Converter
001
RA1/AN1
000
VDD
RA0/AN0
000 or
010 or
100
VREF
(Reference
Voltage)
001 or
011 or
101
PCFG2:PCFG0
FIGURE 10-2:
ANALOG INPUT MODEL
VDD
Rs
ANx
VA
CPIN
5 pF
Sampling
Switch
VT = 0.6 V
VT = 0.6 V
RIC ≤ 1 k
SS
RSS
CHOLD
= DAC capacitance
= 51.2 pF
I leakage
± 500 nA
VSS
Legend: CPIN
= input capacitance
= threshold voltage
VT
I leakage = leakage current at the pin due to
various junctions
= interconnect resistance
RIC
SS
= sampling switch
CHOLD
= sample/hold capacitance (from DAC)
© 2007 Microchip Technology Inc.
6V
5V
VDD 4V
3V
2V
5 6 7 8 9 10 11
Sampling Switch
( kΩ )
DS39597C-page 55
PIC16F72
10.1
A/D Acquisition Requirements
10.3
For the A/D converter to meet its specified accuracy,
the charge holding capacitor (CHOLD) must be allowed
to fully charge to the input channel voltage level. The
analog input model is shown in Figure 10-2. The
source impedance (RS) and the internal sampling
switch (RSS) impedance directly affect the time
required to charge the capacitor CHOLD. The sampling
switch (RSS) impedance varies over the device voltage
(VDD). The source impedance affects the offset voltage
at the analog input (due to pin leakage current).
The ADCON1, and TRISA registers control the operation of the A/D port pins. The port pins that are desired
as analog inputs must have their corresponding TRIS
bits set (input). If the TRIS bit is cleared (output), the
digital output level (VOH or VOL) will be converted.
The A/D operation is independent of the state of the
CHS<2:0> bits and the TRIS bits.
Note 1: When reading the port register, all pins
configured as analog input channels will
read as cleared (a low level). Pins configured as digital inputs, will convert an
analog input. Analog levels on a digitally
configured input will not affect the
conversion accuracy.
The maximum recommended impedance for analog sources is 10 kΩ. After the analog input channel is
selected (changed), this acquisition must be done
before the conversion can be started.
To calculate the minimum acquisition time, TACQ, see
the PIC™ Mid-Range MCU Reference Manual,
(DS33023). In general, however, given a max of 10 kΩ
and at a temperature of 100°C, TACQ will be no more
than 16 μs.
10.2
2: Analog levels on any pin that is defined as
a digital input (including the AN4:AN0
pins), may cause the input buffer to
consume current out of the device
specification.
Selecting the A/D Conversion
Clock
10.4
The A/D conversion time per bit is defined as TAD. The
A/D conversion requires 9.0 TAD per 8-bit conversion.
The source of the A/D conversion clock is software
selectable. The four possible options for TAD are:
•
•
•
•
Note:
A/D Conversions
The GO/DONE bit should NOT be set in
the same instruction that turns on the A/D.
Clearing the GO/DONE bit during a conversion will
abort the current conversion. The ADRES register will
NOT be updated with the partially completed A/D conversion sample. That is, the ADRES register will continue to contain the value of the last completed
conversion (or the last value written to the ADRES register). After the A/D conversion is aborted, a 2 TAD wait
is required before the next acquisition is started. After
this 2 TAD wait, an acquisition is automatically started
on the selected channel. The GO/DONE bit can then
be set to start the conversion.
2 TOSC
8 TOSC
32 TOSC
Internal RC oscillator (2 - 6 μs)
For correct A/D conversions, the A/D conversion clock
(TAD) must be selected to ensure a minimum TAD time
as small as possible, but no less than 1.6 μs and not
greater than 6.4 μs.
Table 10-1 shows the resultant TAD times derived from
the device operating frequencies and the A/D clock
source selected.
TABLE 10-1:
Configuring Analog Port Pins
TAD vs. MAXIMUM DEVICE OPERATING FREQUENCIES (STANDARD DEVICES (C))
AD Clock Source (TAD)
Maximum Device Frequency
Operation
ADCS<1:0>
Max.
2 TOSC
00
1.25 MHz
TOSC
01
5 MHz
32 TOSC
10
20 MHz
RC(1, 2)
11
(Note 1)
8
Note 1: The RC source has a typical TAD time of 4 μs, but can vary between 2-6 μs.
2: When the device frequencies are greater than 1 MHz, the RC A/D conversion clock source is only
recommended for SLEEP operation.
DS39597C-page 56
© 2007 Microchip Technology Inc.
PIC16F72
10.5
A/D Operation During SLEEP
10.6
The A/D module can operate during SLEEP mode. This
requires that the A/D clock source be set to RC
(ADCS1:ADCS0 = 11). When the RC clock source is
selected, the A/D module waits one instruction cycle
before starting the conversion. This allows the SLEEP
instruction to be executed, which eliminates all digital
switching noise from the conversion. When the conversion is completed, the GO/DONE bit will be cleared,
and the result loaded into the ADRES register. If the
A/D interrupt is enabled, the device will wake-up from
SLEEP. If the A/D interrupt is not enabled, the A/D module will then be turned off, although the ADON bit will
remain set.
A device RESET forces all registers to their RESET
state. The A/D module is disabled and any conversion
in progress is aborted. All A/D input pins are configured
as analog inputs.
The ADRES register will contain unknown data after a
Power-on Reset.
10.7
Turning off the A/D places the A/D module in its lowest
current consumption state.
For the A/D module to operate in SLEEP,
the A/D clock source must be set to RC
(ADCS1:ADCS0 = 11). To perform an A/D
conversion in SLEEP, ensure the SLEEP
instruction immediately follows the
instruction that sets the GO/DONE bit.
TABLE 10-2:
Use of the CCP Trigger
An A/D conversion can be started by the “special event
trigger” of the CCP1 module. This requires that the
CCP1M3:CCP1M0 bits (CCP1CON<3:0>) be programmed as 1011 and that the A/D module is enabled
(ADON bit is set). When the trigger occurs, the
GO/DONE bit will be set, starting the A/D conversion,
and the Timer1 counter will be reset to zero. Timer1 is
reset to automatically repeat the A/D acquisition period
with minimal software overhead (moving the ADRES to
the desired location). The appropriate analog input
channel must be selected and the minimum acquisition
done before the “special event trigger” sets the
GO/DONE bit (starts a conversion).
When the A/D clock source is another clock option (not
RC), a SLEEP instruction will cause the present conversion to be aborted and the A/D module to be turned off,
though the ADON bit will remain set.
Note:
Effects of a RESET
If the A/D module is not enabled (ADON is cleared),
then the “special event trigger” will be ignored by the
A/D module, but will still reset the Timer1 counter.
REGISTERS/BITS ASSOCIATED WITH A/D
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
RESETS
INTCON
0Bh,8Bh
10Bh,18Bh
GIE
PEIE
TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF
0000 000x
0000 000u
Address
0Ch
PIR1
—
ADIF
—
—
SSPIF
CCP1IF
TMR2IF TMR1IF -0-- 0000
-0-- 0000
8Ch
PIE1
—
ADIE
—
—
SSPIE
CCP1IE
TMR2IE TMR1IE -0-- 0000
-0-- 0000
1Eh
ADRES
xxxx xxxx
uuuu uuuu
1Fh
ADCON0 ADCS1 ADCS0
0000 00-0
0000 00-0
9Fh
ADCON1
A/D Result Register
—
—
05h
PORTA
—
—
85h
TRISA
—
—
CHS2
CHS1
—
—
RA5
RA4
CHS0 GO/DONE
—
RA3
PCFG2
RA2
PORTA Data Direction Register
—
ADON
PCFG1
PCFG0
---- -000
---- -000
RA0
--0x 0000
--0u 0000
--11 1111
--11 1111
RA1
Legend: x = unknown, u = unchanged, - = unimplemented, read as ‘0’. Shaded cells are not used for A/D conversion.
© 2007 Microchip Technology Inc.
DS39597C-page 57
PIC16F72
NOTES:
DS39597C-page 58
© 2007 Microchip Technology Inc.
PIC16F72
11.0
SPECIAL FEATURES OF THE
CPU
These devices have a host of features intended to maximize system reliability, minimize cost through elimination of external components, provide power saving
Operating modes and offer code protection:
• Oscillator Selection
• RESET
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
• Watchdog Timer (WDT)
• SLEEP
• Code Protection
• ID Locations
• In-Circuit Serial Programming
SLEEP mode is designed to offer a very low current
Power-down mode. The user can wake-up from
SLEEP through external RESET, Watchdog Timer
Wake-up, or through an interrupt.
Several oscillator options are also made available to
allow the part to fit the application. The RC oscillator
option saves system cost while the LP crystal option
saves power. Configuration bits are used to select the
desired oscillator mode.
Additional information on special features is available
in the PIC™ Mid-Range Reference Manual (DS33023).
11.1
Configuration Bits
The configuration bits can be programmed (read as
‘0’), or left unprogrammed (read as ‘1’), to select various device configurations. These bits are mapped in
program memory location 2007h.
The user will note that address 2007h is beyond the
user program memory space, which can be accessed
only during programming.
These devices have a Watchdog Timer, which can be
enabled or disabled using a configuration bit. It runs off
its own RC oscillator for added reliability.
There are two timers that offer necessary delays on
power-up. One is the Oscillator Start-up Timer (OST),
intended to keep the chip in RESET until the crystal
oscillator is stable. The other is the Power-up Timer
(PWRT), which provides a fixed delay of 72 ms (nominal) on power-up only. It is designed to keep the part in
RESET while the power supply stabilizes, and is
enabled or disabled using a configuration bit. With
these two timers on-chip, most applications need no
external RESET circuitry.
© 2007 Microchip Technology Inc.
DS39597C-page 59
PIC16F72
REGISTER 11-1:
CONFIGURATION WORD (ADDRESS 2007h)(1)
U-1
U-1
U-1
U-1
U-1
U-1
U-1
u-1
U-1
u-1
—
—
—
—
—
—
—
BOREN
—
CP
u-1
u-1
u-1
u-1
PWRTEN WDTEN F0SC1 F0SC0
bit13
bit0
bit 13-7
Unimplemented: Read as ‘1’
bit 6
BOREN: Brown-out Reset Enable bit(2)
1 = BOR enabled
0 = BOR disabled
bit 5
Unimplemented: Read as ‘1’
bit 4
CP: FLASH Program Memory Code Protection bit
1 = Code protection off
0 = All memory locations code protected
bit 3
PWRTEN: Power-up Timer Enable bit
1 = PWRT disabled
0 = PWRT enabled
bit 2
WDTEN: Watchdog Timer Enable bit
1 = WDT enabled
0 = WDT disabled
bit 1-0
FOSC1:FOSC0: Oscillator Selection bits
11 = RC oscillator
10 = HS oscillator
01 = XT oscillator
00 = LP oscillator
Note 1: The erased (unprogrammed) value of the configuration word is 3FFFh.
2: Enabling Brown-out Reset automatically enables Power-up Timer (PWRT), regardless of
the value of bit PWRTEN. Ensure the Power-up Timer is enabled any time Brown-out
Reset is enabled.
Legend:
R = Readable bit
P = Programmable bit
- n = Value when device is unprogrammed
DS39597C-page 60
U = Unimplemented bit, read as ‘1’
u = Unchanged from programmed state
© 2007 Microchip Technology Inc.
PIC16F72
11.2
FIGURE 11-2:
Oscillator Configurations
11.2.1
OSCILLATOR TYPES
The PIC16F72 can be operated in four different Oscillator modes. The user can program two configuration
bits (FOSC1 and FOSC0) to select one of these four
modes:
•
•
•
•
LP
XT
HS
RC
EXTERNAL CLOCK INPUT
OPERATION (HS OSC
CONFIGURATION)
Low Power Crystal
Crystal/Resonator
High Speed Crystal/Resonator
Resistor/Capacitor
11.2.2
OSC1
Clock from
Ext. System
PIC16F72
(HS Mode)
Open
CRYSTAL OSCILLATOR/CERAMIC
RESONATORS
In XT, LP or HS modes, a crystal or ceramic resonator
is connected to the OSC1/CLKI and OSC2/CLKO pins
to establish oscillation (Figure 11-1). The PIC16F72
oscillator design requires the use of a parallel cut crystal. Use of a series cut crystal may give a frequency out
of the crystal manufacturers specifications. When in HS
mode, the device can accept an external clock source
to drive the OSC1/CLKI pin (Figure 11-2). See
Figure 14-1 or Figure 14-2 (depending on the part
number and VDD range) for valid external clock
frequencies.
TABLE 11-1:
OSC2
CERAMIC RESONATORS
(FOR DESIGN
GUIDANCE ONLY)
Typical Capacitor Values Used:
Mode
Freq
OSC1
OSC2
XT
455 kHz
2.0 MHz
4.0 MHz
56 pF
47 pF
33 pF
56 pF
47 pF
33 pF
HS
8.0 MHz
16.0 MHz
27 pF
22 pF
27 pF
22 pF
Capacitor values are for design guidance only.
FIGURE 11-1:
C1(1)
CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS, XT OR LP
OSC CONFIGURATION)
OSC1
XTAL
To
internal
logic
RF(3)
OSC2
RS(2)
C2(1)
These capacitors were tested with the resonators
listed below for basic start-up and operation. These
values were not optimized.
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
VDD and temperature range for the application.
See the notes at the bottom of page 62 for additional
information.
SLEEP
PIC16F72
Note 1: See Table 11-1 and Table 11-2 for typical
values of C1 and C2.
2: A series resistor (RS) may be required for
AT strip cut crystals.
3: RF varies with the crystal chosen.
© 2007 Microchip Technology Inc.
DS39597C-page 61
PIC16F72
TABLE 11-2:
Osc Type
LP
XT
HS
CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR (FOR
DESIGN GUIDANCE ONLY)
Crystal
Freq
Typical Capacitor Values
Tested:
C1
C2
32 kHz
33 pF
33 pF
200 kHz
15 pF
15 pF
200 kHz
56 pF
56 pF
1 MHz
15 pF
15 pF
4 MHz
15 pF
15 pF
4 MHz
15 pF
15 pF
8 MHz
15 pF
15 pF
20 MHz
15 pF
15 pF
11.2.3
For timing insensitive applications, the “RC” device
option offers additional cost savings. The RC oscillator
frequency is a function of the supply voltage, the resistor (REXT) and capacitor (CEXT) values, and the operating temperature. In addition to this, the oscillator
frequency will vary from unit to unit due to normal process parameter variation. Furthermore, the difference
in lead frame capacitance between package types will
also affect the oscillation frequency, especially for low
CEXT values. The user also needs to take into account
variation due to tolerance of external R and C components used. Figure 11-3 shows how the R/C
combination is connected to the PIC16F72.
FIGURE 11-3:
These capacitors were tested with the crystals listed
below for basic start-up and operation. These values
were not optimized.
REXT
CEXT
4: Always verify oscillator performance over
the VDD and temperature range that is
expected for the application.
PIC16F72
VSS
FOSC/4
See the notes following this table for additional
information.
3: Rs may be required in HS mode, as well
as XT mode, to avoid overdriving crystals
with low drive level specification.
Internal
Clock
OSC1
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
VDD and temperature range for the application.
2: Since each resonator/crystal has its own
characteristics, the user should consult the
resonator/crystal manufacturer for appropriate values of external components.
RC OSCILLATOR MODE
VDD
Capacitor values are for design guidance only.
Note 1: Higher capacitance increases the stability
of oscillator, but also increases the
start-up time.
RC OSCILLATOR
Recommended values:
11.3
OSC2/CLKO
3 kΩ ≤ REXT ≤ 100 kΩ
CEXT > 20 pF
RESET
The PIC16F72 differentiates between various kinds of
RESET:
•
•
•
•
•
•
Power-on Reset (POR)
MCLR Reset during normal operation
MCLR Reset during SLEEP
WDT Reset (during normal operation)
WDT Wake-up (during SLEEP)
Brown-out Reset (BOR)
Some registers are not affected in any RESET condition. Their status is unknown on POR and unchanged
in any other RESET. Most other registers are reset to a
“RESET state” on Power-on Reset (POR), on the
MCLR and WDT Reset, on MCLR Reset during
SLEEP, and Brown-out Reset (BOR). They are not
affected by a WDT Wake-up, which is viewed as the
resumption of normal operation. The TO and PD bits
are set or cleared differently in different RESET situations, as indicated in Table 11-4. These bits are used in
software to determine the nature of the RESET. See
Table 11-6 for a full description of RESET states of all
registers.
A simplified block diagram of the on-chip RESET circuit
is shown in Figure 11-4.
DS39597C-page 62
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 11-4:
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
External
RESET
MCLR
SLEEP
WDT
Module
WDT
Time-out
Reset
VDD Rise
Detect
Power-on Reset
VDD
Brown-out
Reset
S
BOREN
OST/PWRT
OST
Chip_Reset
10-bit Ripple Counter
R
Q
OSC1
(1)
On-chip
RC OSC
PWRT
10-bit Ripple Counter
Enable PWRT
Enable OST
Note
11.4
1:
This is a separate oscillator from the RC oscillator of the CLKI pin.
MCLR
PIC16F72 device has a noise filter in the MCLR Reset
path. The filter will detect and ignore small pulses.
It should be noted that a WDT Reset does not drive
MCLR pin low.
The behavior of the ESD protection on the MCLR pin
has been altered from previous devices of this family.
Voltages applied to the pin that exceed its specification
can result in both MCLR and excessive current beyond
the device specification during the ESD event. For this
reason, Microchip recommends that the MCLR pin no
longer be tied directly to VDD. The use of an
RC network, as shown in Figure 11-5, is suggested.
© 2007 Microchip Technology Inc.
FIGURE 11-5:
RECOMMENDED MCLR
CIRCUIT
VDD
PIC16F72
R1
1 kΩ (or greater)
MCLR
C1
0.1 μF
(optional, not critical)
DS39597C-page 63
PIC16F72
11.5
Power-on Reset (POR)
A Power-on Reset pulse is generated on-chip when
VDD rise is detected (in the range of 1.2V - 1.7V). To
take advantage of the POR, tie the MCLR pin to VDD,
as described in Section 11.4. A maximum rise time for
VDD is specified. See Section 14.0, Electrical
Characteristics for details.
When the device starts normal operation (exits the
RESET condition), device operating parameters (voltage, frequency, temperature,...) must be met to ensure
operation. If these conditions are not met, the device
must be held in RESET until the operating conditions
are met. For more information, see Application Note,
AN607- Power-up Trouble Shooting (DS00607).
11.6
Power-up Timer (PWRT)
The Power-up Timer provides a fixed 72 ms nominal
time-out on power-up only from the POR. The Powerup Timer operates on an internal RC oscillator. The
chip is kept in RESET as long as the PWRT is active.
The PWRT’s time delay allows VDD to rise to an acceptable level. A configuration bit is provided to enable/
disable the PWRT.
The power-up time delay will vary from chip to chip due
to VDD, temperature and process variation. See DC
parameters for details (TPWRT, parameter #33).
11.7
Oscillator Start-up Timer (OST)
11.9
Time-out Sequence
On power-up, the time-out sequence is as follows: the
PWRT delay starts (if enabled) when a POR occurs.
Then, OST starts counting 1024 oscillator cycles when
PWRT ends (LP, XT, HS). When the OST ends, the
device comes out of RESET.
If MCLR is kept low long enough, all delays will expire.
Bringing MCLR high will begin execution immediately.
This is useful for testing purposes or to synchronize
more than one PIC16F72 device operating in parallel.
Table 11-5 shows the RESET conditions for the
STATUS, PCON and PC registers, while Table 11-6
shows the RESET conditions for all the registers.
11.10 Power Control/Status Register
(PCON)
The Power Control/Status Register, PCON, has two
bits to indicate the type of RESET that last occurred.
Bit0 is Brown-out Reset Status bit, BOR. Bit BOR is
unknown on a Power-on Reset. It must then be set by
the user and checked on subsequent RESETS to see
if bit BOR cleared, indicating a Brown-out Reset
occurred. When the Brown-out Reset is disabled, the
state of the BOR bit is unpredictable.
Bit1 is POR (Power-on Reset Status bit). It is cleared on
a Power-on Reset and unaffected otherwise. The user
must set this bit following a Power-on Reset.
The Oscillator Start-up Timer (OST) provides 1024
oscillator cycles (from OSC1 input) delay after the
PWRT delay is over (if enabled). This helps to ensure
that the crystal oscillator or resonator has started and
stabilized.
The OST time-out is invoked only for XT, LP and HS
modes and only on Power-on Reset or wake-up from
SLEEP.
11.8
Brown-out Reset (BOR)
The configuration bit, BOREN, can enable or disable
the Brown-out Reset circuit. If VDD falls below VBOR
(parameter D005, about 4V) for longer than TBOR
(parameter #35, about 100 μs), the brown-out situation
will reset the device. If VDD falls below VBOR for less
than TBOR, a RESET may not occur.
Once the brown-out occurs, the device will remain in
Brown-out Reset until VDD rises above VBOR. The
Power-up Timer then keeps the device in RESET for
TPWRT (parameter #33, about 72 ms). If VDD should fall
below VBOR during TPWRT, the Brown-out Reset process will restart when VDD rises above VBOR, with the
Power-up Timer Reset. The Power-up Timer is always
enabled when the Brown-out Reset circuit is enabled,
regardless of the state of the PWRT configuration bit.
DS39597C-page 64
© 2007 Microchip Technology Inc.
PIC16F72
TABLE 11-3:
TIME-OUT IN VARIOUS SITUATIONS
Power-up
Oscillator Configuration
Brown-out
Wake-up from
SLEEP
PWRTEN = 0
PWRTEN = 1
XT, HS, LP
72 ms + 1024 TOSC
1024 TOSC
72 ms + 1024 TOSC
1024 TOSC
RC
72 ms
—
72 ms
—
TABLE 11-4:
STATUS BITS AND THEIR SIGNIFICANCE
BOR
TO
PD
POR
(PCON<1>) (PCON<0>) (STATUS<4>) (STATUS<3>)
Significance
0
x
1
1
Power-on Reset
0
x
0
x
Illegal, TO is set on POR
0
x
x
0
Illegal, PD is set on POR
u
0
1
1
Brown-out Reset
u
u
0
1
WDT Reset
u
u
0
0
WDT Wake-up
u
u
u
u
MCLR Reset during normal operation
u
u
1
0
MCLR Reset during SLEEP or interrupt wake-up from
SLEEP
TABLE 11-5:
RESET CONDITION FOR SPECIAL REGISTERS
Program
Counter
STATUS
Register
PCON
Register
Power-on Reset
000h
0001 1xxx
---- --0x
MCLR Reset during normal operation
000h
000u uuuu
---- --uu
MCLR Reset during SLEEP
000h
0001 0uuu
---- --uu
WDT Reset
000h
0000 1uuu
---- --uu
PC + 1
uuu0 0uuu
---- --uu
000h
0001 1uuu
---- --u0
uuu1 0uuu
---- --uu
Condition
WDT Wake-up
Brown-out Reset
Interrupt Wake-up from SLEEP
(1)
PC + 1
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0'.
Note 1: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector
(0004h).
© 2007 Microchip Technology Inc.
DS39597C-page 65
PIC16F72
TABLE 11-6:
Register
W
INITIALIZATION CONDITIONS FOR ALL REGISTERS
Power-on Reset,
Brown-out Reset
xxxx xxxx
MCLR Reset,
WDT Reset
uuuu uuuu
INDF
N/A
N/A
TMR0
xxxx xxxx
uuuu uuuu
0000h
0000h
PCL
Wake-up via WDT or
Interrupt
uuuu uuuu
N/A
uuuu uuuu
PC + 1(2)
(3)
STATUS
0001 1xxx
000q quuu
uuuq quuu(3)
FSR
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTA
--0x 0000
--0u 0000
--uu uuuu
PORTB
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTC
xxxx xxxx
uuuu uuuu
uuuu uuuu
PCLATH
---0 0000
---0 0000
---u uuuu
INTCON
0000 000x
0000 000u
uuuu uuuu(1)
PIR1
-0-- 0000
-0-- 0000
-u-- uuuu(1)
TMR1L
xxxx xxxx
uuuu uuuu
uuuu uuuu
TMR1H
xxxx xxxx
uuuu uuuu
uuuu uuuu
T1CON
--00 0000
--uu uuuu
--uu uuuu
TMR2
0000 0000
0000 0000
uuuu uuuu
T2CON
-000 0000
-000 0000
-uuu uuuu
SSPBUF
xxxx xxxx
uuuu uuuu
uuuu uuuu
SSPCON
0000 0000
0000 0000
uuuu uuuu
CCPR1L
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCPR1H
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCP1CON
--00 0000
--00 0000
--uu uuuu
ADRES
xxxx xxxx
uuuu uuuu
uuuu uuuu
ADCON0
0000 00-0
0000 00-0
uuuu uu-u
OPTION
1111 1111
1111 1111
uuuu uuuu
TRISA
--11 1111
--11 1111
--uu uuuu
TRISB
1111 1111
1111 1111
uuuu uuuu
TRISC
1111 1111
1111 1111
uuuu uuuu
PIE1
-0-- 0000
-0-- 0000
-u-- uuuu
PCON
---- --qq
---- --uu
---- --uu
PR2
1111 1111
1111 1111
1111 1111
SSPADD
0000 0000
0000 0000
uuuu uuuu
SSPSTAT
--00 0000
--00 0000
--uu uuuu
ADCON1
---- -000
---- -000
---- -uuu
PMDATL
0--- 0000
0--- 0000
u--- uuuu
PMADRL
xxxx xxxx
uuuu uuuu
uuuu uuuu
PMDATH
xxxx xxxx
uuuu uuuu
uuuu uuuu
PMADRH
xxxx xxxx
uuuu uuuu
uuuu uuuu
PMCON1
1--- ---0
1--- ---0
1--- ---u
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', q = value depends on condition,
r = reserved, maintain clear.
Note 1: One or more bits in INTCON, PIR1 will be affected (to cause wake-up).
2: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector
(0004h).
3: See Table 11-5 for RESET value for specific condition.
DS39597C-page 66
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 11-6:
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD THROUGH
PULL-UP RESISTOR)
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
FIGURE 11-7:
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD THROUGH
RC NETWORK): CASE 1
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
FIGURE 11-8:
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD THROUGH
RC NETWORK): CASE 2
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
© 2007 Microchip Technology Inc.
DS39597C-page 67
PIC16F72
FIGURE 11-9:
SLOW RISE TIME (MCLR TIED TO VDD THROUGH RC NETWORK)
5V
VDD
1V
0V
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
11.11 Interrupts
The RB0/INT pin interrupt, the RB port change interrupt
and the TMR0 overflow interrupt flags are contained in
the INTCON register.
The PIC16F72 has up to eight sources of interrupt. The
interrupt control register (INTCON) records individual
interrupt requests in flag bits. It also has individual and
global interrupt enable bits.
Note:
The peripheral interrupt flags are contained in the
Special Function Register, PIR1. The corresponding
interrupt enable bits are contained in Special Function
Register, PIE1, and the peripheral interrupt enable bit
is contained in Special Function Register INTCON.
Individual interrupt flag bits are set, regardless of the status of their corresponding
mask bit, or the GIE bit.
When an interrupt is serviced, the GIE bit is cleared to
disable any further interrupt, the return address is
pushed onto the stack, and the PC is loaded with
0004h. Once in the Interrupt Service Routine, the
source(s) of the interrupt can be determined by polling
the interrupt flag bits. The interrupt flag bit(s) must be
cleared in software before re-enabling interrupts to
avoid recursive interrupts.
A global interrupt enable bit, GIE (INTCON<7>)
enables (if set) all unmasked interrupts, or disables (if
cleared) all interrupts. When bit GIE is enabled, and an
interrupt’s flag bit and mask bit are set, the interrupt will
vector immediately. Individual interrupts can be disabled through their corresponding enable bits in various registers. Individual interrupt bits are set,
regardless of the status of the GIE bit. The GIE bit is
cleared on RESET.
For external interrupt events, such as the INT pin or
PORTB change interrupt, the interrupt latency will be
three or four instruction cycles. The exact latency
depends when the interrupt event occurs, relative to
the current Q cycle. The latency is the same for one or
two cycle instructions. Individual interrupt flag bits are
set, regardless of the status of their corresponding
mask bit, PEIE bit, or the GIE bit.
The “return from interrupt” instruction, RETFIE, exits
the interrupt routine, as well as sets the GIE bit, which
re-enables interrupts.
FIGURE 11-10:
INTERRUPT LOGIC
TMR0IF
TMR0IE
INTF
INTE
ADIF
ADIE
SSPIF
SSPIE
CCP1IF
CCP1IE
TMR1IF
TMR1IE
Wake-up (If in SLEEP mode)
Interrupt to CPU
RBIF
RBIE
PEIE
GIE
TMR2IF
TMR2IE
DS39597C-page 68
© 2007 Microchip Technology Inc.
PIC16F72
11.11.1
INT INTERRUPT
11.11.3
External interrupt on the RB0/INT pin is edge triggered,
either rising, if bit INTEDG (OPTION<6>) is set, or falling, if the INTEDG bit is clear. When a valid edge
appears on the RB0/INT pin, flag bit INTF
(INTCON<1>) is set. This interrupt can be disabled by
clearing enable bit INTE (INTCON<4>). Flag bit INTF
must be cleared in software in the Interrupt Service
Routine before re-enabling this interrupt. The INT interrupt can wake-up the processor from SLEEP, if bit INTE
was set prior to going into SLEEP. The status of global
interrupt enable bit GIE decides whether or not the
processor branches to the interrupt vector following
wake-up. See Section 11.14 for details on SLEEP
mode.
11.11.2
TMR0 INTERRUPT
An overflow (FFh → 00h) in the TMR0 register will set
flag bit TMR0IF (INTCON<2>). The interrupt can be
enabled/disabled by setting/clearing enable bit
TMR0IE (INTCON<5>) (see Section 4.0).
EXAMPLE 11-1:
PORTB INTCON CHANGE
An input change on PORTB<7:4> sets flag bit RBIF
(INTCON<0>). The interrupt can be enabled/disabled
by setting/clearing enable bit RBIE (INTCON<4>) (see
Section 3.2).
11.12 Context Saving During Interrupts
During an interrupt, only the return PC value is saved
on the stack. Typically, users may wish to save key registers during an interrupt (i.e., W, STATUS registers).
This will have to be implemented in software, as shown
in Example 11-1.
For the PIC16F72 device, the register W_TEMP must
be defined in both banks 0 and 1 and must be defined
at the same offset from the bank base address (i.e., if
W_TEMP is defined at 20h in bank 0, it must also be
defined at A0h in bank 1). The register STATUS_TEMP
is only defined in bank 0.
SAVING STATUS, W AND PCLATH REGISTERS IN RAM
MOVWF
SWAPF
CLRF
MOVWF
:
:(ISR)
:
SWAPF
W_TEMP
STATUS,W
STATUS
STATUS_TEMP
MOVWF
SWAPF
SWAPF
STATUS
W_TEMP,F
W_TEMP,W
;Copy
;Swap
;bank
;Save
W to TEMP register
status to be saved into W
0, regardless of current bank, Clears IRP,RP1,RP0
status to bank zero STATUS_TEMP register
;Insert user code here
STATUS_TEMP,W
© 2007 Microchip Technology Inc.
;Swap STATUS_TEMP register into W
;(sets bank to original state)
;Move W into STATUS register
;Swap W_TEMP
;Swap W_TEMP into W
DS39597C-page 69
PIC16F72
11.13 Watchdog Timer (WDT)
The Watchdog Timer is a free running, on-chip RC
oscillator that does not require any external components. This RC oscillator is separate from the RC oscillator of the OSC1/CLKI pin. That means that the WDT
will run, even if the clock on the OSC1/CLKI and OSC2/
CLKO pins of the device has been stopped, for
example, by execution of a SLEEP instruction.
WDT time-out period values may be found in the Electrical Specifications section under parameter #31. Values for the WDT prescaler (actually a postscaler, but
shared with the Timer0 prescaler) may be assigned
using the OPTION register.
Note 1: The CLRWDT and SLEEP instructions
clear the WDT and the postscaler, if
assigned to the WDT, and prevent it from
timing out and generating a device
RESET condition.
During normal operation, a WDT time-out generates a
device RESET (Watchdog Timer Reset). If the device is
in SLEEP mode, a WDT time-out causes the device to
wake-up and continue with normal operation (Watchdog
Timer Wake-up). The TO bit in the STATUS register will
be cleared upon a Watchdog Timer time-out.
2: When a CLRWDT instruction is executed
and the prescaler is assigned to the WDT,
the prescaler count will be cleared, but
the prescaler assignment is not changed.
The WDT can be permanently disabled by clearing
configuration bit WDTEN (see Section 11.1).
FIGURE 11-11:
WATCHDOG TIMER BLOCK DIAGRAM
From TMR0 Clock Source
(Figure 4-1)
0
WDT Timer
1
Postscaler
M
U
X
8
8 - to - 1 MUX
PS2:PS0
PSA
WDT
Enable Bit
To TMR0 (Figure 4-1)
0
1
MUX
PSA
WDT
Time-out
Note: PSA and PS2:PS0 are bits in the OPTION register.
TABLE 11-7:
Address
SUMMARY OF WATCHDOG TIMER REGISTERS
Name
2007h
Config. bits
81h,181h
OPTION
Bit 7
Bit 6
Bit 5
Bit 4
(1)
BOREN(1)
—
CP
RBPU
INTEDG
T0CS
T0SE
Bit 3
Bit 2
PWRTEN(1) WDTEN
PSA
PS2
Bit 1
Bit 0
FOSC1
FOSC0
PS1
PS0
Legend: Shaded cells are not used by the Watchdog Timer.
Note 1: See Register 11-1 for operation of these bits.
DS39597C-page 70
© 2007 Microchip Technology Inc.
PIC16F72
11.14 Power-down Mode (SLEEP)
Power-down mode is entered by executing a SLEEP
instruction.
If enabled, the Watchdog Timer will be cleared but
keeps running, the PD bit (STATUS<3>) is cleared, the
TO (STATUS<4>) bit is set, and the oscillator driver is
turned off. The I/O ports maintain the status they had
before the SLEEP instruction was executed (driving
high, low, or hi-impedance).
For lowest current consumption in this mode, place all
I/O pins at either VDD or VSS, ensure no external circuitry is drawing current from the I/O pin, power-down
the A/D and disable external clocks. Pull all I/O pins
that are hi-impedance inputs, high or low externally, to
avoid switching currents caused by floating inputs. The
T0CKI input should also be at VDD or VSS for lowest
current consumption. The contribution from on-chip
pull-ups on PORTB should also be considered.
The MCLR pin must be at a logic high level (VIHMC).
11.14.1
WAKE-UP FROM SLEEP
The device can wake-up from SLEEP through one of
the following events:
1.
2.
3.
External RESET input on MCLR pin.
Watchdog Timer wake-up (if WDT was
enabled).
Interrupt from INT pin, RB port change or a
peripheral interrupt.
External MCLR Reset will cause a device RESET. All
other events are considered a continuation of program
execution and cause a "wake-up". The TO and PD bits
in the STATUS register can be used to determine the
cause of the device RESET. The PD bit, which is set on
power-up, is cleared when SLEEP is invoked. The TO
bit is cleared if a WDT time-out occurred and caused
wake-up.
The following peripheral interrupts can wake the device
from SLEEP:
1.
2.
3.
4.
5.
6.
Other peripherals cannot generate interrupts since
during SLEEP, no on-chip clocks are present.
When the SLEEP instruction is being executed, the next
instruction (PC + 1) is pre-fetched. For the device to
wake-up through an interrupt event, the corresponding
interrupt enable bit must be set (enabled). Wake-up
occurs regardless of the state of the GIE bit. If the GIE
bit is clear (disabled), the device continues execution at
the instruction after the SLEEP instruction. If the GIE bit
is set (enabled), the device executes the instruction
after the SLEEP instruction and then branches to the
interrupt address (0004h). In cases where the execution of the instruction following SLEEP is not desirable,
the user should have a NOP after the SLEEP instruction.
11.14.2
WAKE-UP USING INTERRUPTS
When global interrupts are disabled (GIE cleared) and
any interrupt source has both its interrupt enable bit
and interrupt flag bit set, one of the following will occur:
• If the interrupt occurs before the execution of a
SLEEP instruction, the SLEEP instruction will complete as a NOP. Therefore, the WDT and WDT
postscaler will not be cleared, the TO bit will not
be set and PD bits will not be cleared.
• If the interrupt occurs during or after the execution of a SLEEP instruction, the device will immediately wake-up from SLEEP. The SLEEP
instruction will be completely executed before the
wake-up. Therefore, the WDT and WDT
postscaler will be cleared, the TO bit will be set
and the PD bit will be cleared.
Even if the flag bits were checked before executing a
SLEEP instruction, it may be possible for flag bits to
become set before the SLEEP instruction completes. To
determine whether a SLEEP instruction executed, test
the PD bit. If the PD bit is set, the SLEEP instruction
was executed as a NOP.
To ensure that the WDT is cleared, a CLRWDT instruction
should be executed before a SLEEP instruction.
TMR1 interrupt. Timer1 must be operating as an
asynchronous counter.
CCP Capture mode interrupt.
Special event trigger (Timer1 in Asynchronous
mode using an external clock).
SSP (START/STOP) bit detect interrupt.
SSP transmit or receive in Slave mode
(SPI/I2C).
A/D conversion (when A/D clock source is RC).
© 2007 Microchip Technology Inc.
DS39597C-page 71
PIC16F72
FIGURE 11-12:
WAKE-UP FROM SLEEP THROUGH INTERRUPT
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
TOST(2)
CLKO(4)
INT pin
INTF Flag
(INTCON<1>)
Interrupt Latency
(Note 2)
GIE bit
(INTCON<7>)
Processor in
SLEEP
INSTRUCTION FLOW
PC
Instruction
Fetched
Instruction
Executed
Note
1:
2:
3:
4:
PC
PC+1
Inst(PC) = SLEEP
Inst(PC + 1)
PC+2
Inst(PC + 2)
PC+2
Inst(PC - 1)
SLEEP
Inst(PC + 1)
PC + 2
Dummy cycle
0004h
0005h
Inst(0004h)
Inst(0005h)
Dummy cycle
Inst(0004h)
XT, HS or LP Oscillator mode assumed.
TOST = 1024 TOSC (drawing not to scale) This delay will not be there for RC Osc mode.
GIE = ‘1' assumed. In this case, after wake-up, the processor jumps to the interrupt routine.
If GIE = ‘0', execution will continue in-line.
CLKO is not available in these Osc modes, but shown here for timing reference.
11.15 Program Verification/
Code Protection
FIGURE 11-13:
TYPICAL IN-CIRCUIT
SERIAL PROGRAMMING
CONNECTION
If the code protection bit(s) have not been programmed, the on-chip program memory can be read
out for verification purposes.
11.16 ID Locations
Four memory locations (2000h - 2003h) are designated
as ID locations, where the user can store checksum or
other code identification numbers. These locations are
not accessible during normal execution, but are readable and writable during program/verify. It is recommended that only the four Least Significant bits of the
ID location are used.
11.17 In-Circuit Serial Programming
PIC16F72 microcontrollers can be serially programmed
while in the end application circuit. This is simply done
with two lines for clock and data and three other lines for
power, ground, and the programming voltage (see
Figure 11-13 for an example). This allows customers to
manufacture boards with unprogrammed devices, and
then program the microcontroller just before shipping
the product. This also allows the most recent firmware
or a custom firmware to be programmed.
To Normal
Connections
External
Connector
Signals
*
PIC16F72
+5V
VDD
0V
VSS
VPP
MCLR/VPP
CLK
RB6
Data I/O
RB7
*
*
*
VDD
To Normal
Connections
* Isolation devices (as required).
For general information of serial programming, please
refer to the In-Circuit Serial Programming™ (ICSP™)
Guide (DS30277). For specific details on programming
commands and operations for the PIC16F72 devices,
please refer to the latest version of the PIC16F72
FLASH Program Memory Programming Specification
(DS39588).
DS39597C-page 72
© 2007 Microchip Technology Inc.
PIC16F72
12.0
INSTRUCTION SET SUMMARY
Each PIC16F72 instruction is a 14-bit word divided into
an OPCODE that specifies the instruction type and one
or more operands that further specify the operation of
the instruction. The PIC16F72 instruction set summary
in Table 12-2 lists byte-oriented, bit-oriented, and literal and control operations. Table 12-1 shows the
opcode field descriptions.
For byte-oriented instructions, ‘f’ represents a file register designator and ‘d’ represents a destination designator. The file register designator specifies which file
register is to be used by the instruction.
The destination designator specifies where the result of
the operation is to be placed. If ‘d’ is zero, the result is
placed in the W register. If ‘d’ is one, the result is placed
in the file register specified in the instruction.
For bit-oriented instructions, ‘b’ represents a bit field
designator which selects the number of the bit affected
by the operation, while ‘f’ represents the number of the
file in which the bit is located.
For literal and control operations, ‘k’ represents an
eight or eleven-bit constant or literal value.
TABLE 12-1:
OPCODE FIELD
DESCRIPTIONS
Field
Figure 12-1 shows the general formats that the
instructions can have.
All examples use the following format to represent a
hexadecimal number:
0xhh
where h signifies a hexadecimal digit.
FIGURE 12-1:
GENERAL FORMAT FOR
INSTRUCTIONS
Byte-oriented file register operations
13
8 7 6
OPCODE
d
f (FILE #)
0
d = 0 for destination W
d = 1 for destination f
f = 7-bit file register address
Bit-oriented file register operations
13
10 9
7 6
OPCODE
b (BIT #)
f (FILE #)
0
b = 3-bit bit address
f = 7-bit file register address
Literal and control operations
Description
f
Register file address (0x00 to 0x7F)
W
Working register (accumulator)
b
Bit address within an 8-bit file register
k
Literal field, constant data or label
x
Don't care location (= 0 or 1).
The assembler will generate code with x = 0. It is the
recommended form of use for compatibility with all
Microchip software tools.
d
Table 12-2 lists the instructions recognized by the
MPASMTM assembler.
Destination select; d = 0: store result in W,
d = 1: store result in file register f.
Default is d = 1.
PC
Program Counter
TO
Time-out bit
PD
Power-down bit
General
13
8
7
OPCODE
0
k (literal)
k = 8-bit immediate value
CALL and GOTO instructions only
13
11
OPCODE
10
0
k (literal)
k = 11-bit immediate value
A description of each instruction is available in the
PIC™ Mid-Range MCU Family Reference Manual
(DS33023).
The instruction set is highly orthogonal and is grouped
into three basic categories:
• Byte-oriented operations
• Bit-oriented operations
• Literal and control operations
All instructions are executed within one single instruction cycle, unless a conditional test is true or the program counter is changed as a result of an instruction.
In this case, the execution takes two instruction cycles,
with the second cycle executed as a NOP. One instruction cycle consists of four oscillator periods. Thus, for
an oscillator frequency of 4 MHz, the normal instruction
execution time is 1 μs. If a conditional test is true, or the
program counter is changed as a result of an
instruction, the instruction execution time is 2 μs.
© 2007 Microchip Technology Inc.
DS39597C-page 73
PIC16F72
TABLE 12-2:
Mnemonic,
Operands
PIC16F72 INSTRUCTION SET
Description
Cycles
14-Bit Opcode
MSb
LSb
Status
Affected
Notes
BYTE-ORIENTED FILE REGISTER OPERATIONS
ADDWF
ANDWF
CLRF
CLRW
COMF
DECF
DECFSZ
INCF
INCFSZ
IORWF
MOVF
MOVWF
NOP
RLF
RRF
SUBWF
SWAPF
XORWF
f, d
f, d
f
f, d
f, d
f, d
f, d
f, d
f, d
f, d
f
f, d
f, d
f, d
f, d
f, d
Add W and f
AND W with f
Clear f
Clear W
Complement f
Decrement f
Decrement f, Skip if 0
Increment f
Increment f, Skip if 0
Inclusive OR W with f
Move f
Move W to f
No Operation
Rotate Left f through Carry
Rotate Right f through Carry
Subtract W from f
Swap nibbles in f
Exclusive OR W with f
1
1
1
1
1
1
1(2)
1
1(2)
1
1
1
1
1
1
1
1
1
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
0111
0101
0001
0001
1001
0011
1011
1010
1111
0100
1000
0000
0000
1101
1100
0010
1110
0110
dfff
dfff
lfff
0xxx
dfff
dfff
dfff
dfff
dfff
dfff
dfff
lfff
0xx0
dfff
dfff
dfff
dfff
dfff
ffff
ffff
ffff
xxxx
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
0000
ffff
ffff
ffff
ffff
ffff
00bb
01bb
10bb
11bb
bfff
bfff
bfff
bfff
ffff
ffff
ffff
ffff
111x
1001
0kkk
0000
1kkk
1000
00xx
0000
01xx
0000
0000
110x
1010
kkkk
kkkk
kkkk
0110
kkkk
kkkk
kkkk
0000
kkkk
0000
0110
kkkk
kkkk
kkkk
kkkk
kkkk
0100
kkkk
kkkk
kkkk
1001
kkkk
1000
0011
kkkk
kkkk
C,DC,Z
Z
Z
Z
Z
Z
Z
Z
Z
C
C
C,DC,Z
Z
1,2
1,2
2
1,2
1,2
1,2,3
1,2
1,2,3
1,2
1,2
1,2
1,2
1,2
1,2
1,2
BIT-ORIENTED FILE REGISTER OPERATIONS
BCF
BSF
BTFSC
BTFSS
f, b
f, b
f, b
f, b
Bit Clear f
Bit Set f
Bit Test f, Skip if Clear
Bit Test f, Skip if Set
1
1
1 (2)
1 (2)
ADDLW
ANDLW
CALL
CLRWDT
GOTO
IORLW
MOVLW
RETFIE
RETLW
RETURN
SLEEP
SUBLW
XORLW
k
k
k
k
k
k
k
k
k
Add literal and W
AND literal with W
Call subroutine
Clear Watchdog Timer
Go to address
Inclusive OR literal with W
Move literal to W
Return from interrupt
Return with literal in W
Return from Subroutine
Go into Standby mode
Subtract W from literal
Exclusive OR literal with W
01
01
01
01
1,2
1,2
3
3
LITERAL AND CONTROL OPERATIONS
1
1
2
1
2
1
1
2
2
2
1
1
1
11
11
10
00
10
11
11
00
11
00
00
11
11
C,DC,Z
Z
TO,PD
Z
TO,PD
C,DC,Z
Z
Note 1:
When an I/O register is modified as a function of itself (e.g., MOVF PORTB, 1), the value used will be that value present on
the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is driven low by an external
device, the data will be written back with a ‘0’.
2: If this instruction is executed on the TMR0 register (and where applicable, d = 1), the prescaler will be cleared if assigned
to the Timer0 module.
3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is
executed as a NOP.
Note:
Additional information on the mid-range instruction set is available in the PIC™ Mid-Range MCU Family Reference
Manual (DS33023).
DS39597C-page 74
© 2007 Microchip Technology Inc.
PIC16F72
12.1
Instruction Descriptions
ADDLW
Add Literal and W
ANDWF
AND W with f
Syntax:
[ label ] ADDLW
Syntax:
[ label ] ANDWF
Operands:
0 ≤ k ≤ 255
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(W) + k → (W)
Status Affected:
C, DC, Z
Operation:
(W) .AND. (f) → (destination)
The contents of the W register
are added to the eight-bit literal ‘k’
and the result is placed in the W
register.
Status Affected:
Z
Description:
AND the W register with register
‘f’. If ‘d’ = ‘0’, the result is stored in
the W register. If ‘d’ = ‘1’, the
result is stored back in register ‘f’.
ADDWF
Add W and f
BCF
Bit Clear f
Syntax:
[ label ] ADDWF
Syntax:
[ label ] BCF
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
0≤b≤7
Operation:
(W) + (f) → (destination)
Operation:
0 → (f<b>)
Status Affected:
C, DC, Z
Status Affected:
None
Description:
Add the contents of the W register
with register ‘f’. If ‘d’ = ‘0’, the
result is stored in the W register. If
‘d’ = ‘1’, the result is stored back
in register ‘f’.
Description:
Bit ‘b’ in register ‘f’ is cleared.
ANDLW
AND Literal with W
BSF
Bit Set f
Syntax:
[ label ] ANDLW
Syntax:
[ label ] BSF
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
(W) .AND. (k) → (W)
0 ≤ f ≤ 127
0≤b≤7
Status Affected:
Z
Description:
Description:
k
f,d
k
The contents of W register are
AND’ed with the eight-bit literal
‘k’. The result is placed in the W
register.
© 2007 Microchip Technology Inc.
f,d
f,b
f,b
Operation:
1 → (f<b>)
Status Affected:
None
Description:
Bit ‘b’ in register ‘f’ is set.
DS39597C-page 75
PIC16F72
BTFSS
Bit Test f, Skip if Set
CLRF
Clear f
Syntax:
[ label ] BTFSS f,b
Syntax:
[ label ] CLRF
Operands:
0 ≤ f ≤ 127
0≤b<7
Operands:
0 ≤ f ≤ 127
Operation:
Operation:
skip if (f<b>) = 1
00h → (f)
1→Z
Status Affected:
None
Status Affected:
Z
Description:
If bit ‘b’ in register ‘f’ = ‘0’, the next
instruction is executed.
If bit ‘b’ = ‘1’, then the next instruction is discarded and a NOP is executed instead, making this a 2 TCY
instruction.
Description:
The contents of register ‘f’ are
cleared and the Z bit is set.
BTFSC
Bit Test, Skip if Clear
CLRW
Clear W
Syntax:
[ label ] BTFSC f,b
Syntax:
[ label ] CLRW
Operands:
0 ≤ f ≤ 127
0≤b≤7
Operands:
None
Operation:
Operation:
skip if (f<b>) = 0
00h → (W)
1→Z
Status Affected:
None
Status Affected:
Z
Description:
If bit ‘b’ in register ‘f’ = ‘1’, the next
instruction is executed.
If bit ‘b’ in register ‘f’ = ‘0’, the next
instruction is discarded, and a NOP
is executed instead, making this a
2 TCY instruction.
Description:
W register is cleared. Zero bit (Z)
is set.
CALL
Call Subroutine
CLRWDT
Clear Watchdog Timer
Syntax:
[ label ] CALL k
Syntax:
[ label ] CLRWDT
Operands:
0 ≤ k ≤ 2047
Operands:
None
Operation:
(PC) + 1 → TOS,
k → PC<10:0>,
(PCLATH<4:3>) → PC<12:11>
Operation:
Status Affected:
None
00h → WDT
0 → WDT prescaler,
1 → TO
1 → PD
Description:
Call Subroutine. First, return
address (PC+1) is pushed onto
the stack. The eleven-bit immediate address is loaded into PC bits
<10:0>. The upper bits of the PC
are loaded from PCLATH. CALL is
a two-cycle instruction.
Status Affected:
TO, PD
Description:
CLRWDT instruction resets the
Watchdog Timer. It also resets the
prescaler of the WDT. Status bits
TO and PD are set.
DS39597C-page 76
f
© 2007 Microchip Technology Inc.
PIC16F72
COMF
Complement f
Syntax:
[ label ] COMF
GOTO
Unconditional Branch
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ k ≤ 2047
Operation:
(f) → (destination)
Operation:
k → PC<10:0>
PCLATH<4:3> → PC<12:11>
Status Affected:
Z
Status Affected:
None
Description:
The contents of register ‘f’ are
complemented. If ‘d’ = ‘0’, the
result is stored in W. If ‘d’ = ‘1’, the
result is stored back in register ‘f’.
Description:
GOTO is an unconditional branch.
The eleven-bit immediate value is
loaded into PC bits <10:0>. The
upper bits of PC are loaded from
PCLATH<4:3>. GOTO is a
two-cycle instruction.
DECF
Decrement f
INCF
Increment f
Syntax:
[ label ] DECF f,d
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) - 1 → (destination)
Operation:
(f) + 1 → (destination)
Status Affected:
Z
Status Affected:
Z
Description:
Decrement register ‘f’. If ‘d’ = ‘0’,
the result is stored in the W
register. If ‘d’ = ‘1’, the result is
stored back in register ‘f’.
Description:
The contents of register ‘f’ are
incremented. If ‘d’ = ‘0’, the result
is placed in the W register. If
‘d’ = ‘1’, the result is placed back
in register ‘f’.
DECFSZ
Decrement f, Skip if 0
INCFSZ
Increment f, Skip if 0
Syntax:
[ label ] DECFSZ f,d
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) - 1 → (destination);
skip if result = 0
Operation:
(f) + 1 → (destination),
skip if result = 0
Status Affected:
None
Status Affected:
None
Description:
The contents of register ‘f’ are
decremented. If ‘d’ = ‘0’, the result
is placed in the W register. If
‘d’ = ‘1’, the result is placed back
in register ‘f’.
If the result is ‘1’, the next instruction is executed. If the result is ‘0’,
then a NOP is executed instead,
making it a 2 TCY instruction.
Description:
The contents of register ‘f’ are
incremented. If ‘d’ = ‘0’, the result
is placed in the W register. If
‘d’ = ‘1’, the result is placed back
in register ‘f’.
If the result is ‘1’, the next instruction is executed. If the result is ‘0’,
a NOP is executed instead, making
it a 2 TCY instruction.
© 2007 Microchip Technology Inc.
f,d
GOTO k
INCF f,d
INCFSZ f,d
DS39597C-page 77
PIC16F72
IORLW
Inclusive OR Literal with W
MOVLW
Move Literal to W
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operands:
0 ≤ k ≤ 255
Operation:
(W) .OR. k → (W)
Operation:
k → (W)
Status Affected:
Z
Status Affected:
None
Description:
The contents of the W register are
OR’d with the eight-bit literal ‘k’.
The result is placed in the W
register.
Description:
The eight-bit literal ‘k’ is loaded
into W register. The don’t cares
will assemble as ‘0’s.
IORWF
Inclusive OR W with f
MOVWF
Move W to f
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
Operation:
(W) .OR. (f) → (destination)
(W) → (f)
Operation:
Status Affected:
None
Status Affected:
Z
Description:
Description:
Inclusive OR the W register with
register ‘f’. If ‘d’ = ‘0’, the result is
placed in the W register. If ‘d’ = ‘1’,
the result is placed back in
register ‘f’.
Move data from W register to
register ‘f’.
MOVF
Move f
NOP
No Operation
IORLW k
IORWF
f,d
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) → (destination)
Status Affected:
Z
Description:
The contents of register ‘f’ are
moved to a destination dependant
upon the status of ‘d’. If ‘d’ = ‘0’,
the destination is W register. If
‘d’ = ‘1’, the destination is file register ‘f’ itself. ‘d’ = ‘1’ is useful to
test a file register, since status
flag Z is affected.
DS39597C-page 78
MOVF f,d
MOVLW k
MOVWF
Syntax:
[ label ]
Operands:
None
Operation:
No operation
Status Affected:
None
Description:
No operation.
f
NOP
© 2007 Microchip Technology Inc.
PIC16F72
RETFIE
Return from Interrupt
RLF
Rotate Left f through Carry
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
None
Operands:
Operation:
TOS → PC,
1 → GIE
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
See description below
Status Affected:
None
Status Affected:
C
Description:
The contents of register ‘f’ are
rotated one bit to the left through
the Carry Flag. If ‘d’ = ‘0’, the
result is placed in the W register.
If ‘d’ = ‘1’, the result is stored
back in register ‘f’.
RETFIE
RLF
C
f,d
Register f
RETLW
Return with Literal in W
RRF
Rotate Right f through Carry
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
k → (W);
TOS → PC
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
See description below
Status Affected:
None
Status Affected:
C
Description:
The W register is loaded with the
eight-bit literal ‘k’. The program
counter is loaded from the top of
the stack (the return address).
This is a two-cycle instruction.
Description:
The contents of register ‘f’ are
rotated one bit to the right through
the Carry Flag. If ‘d’ = ‘0’, the
result is placed in the W register.
If ‘d’ = ‘1’, the result is placed back
in register ‘f’.
RETLW k
RRF f,d
C
Register f
RETURN
Return from Subroutine
SLEEP
Syntax:
[ label ]
Syntax:
Operands:
None
Operands:
None
Operation:
TOS → PC
Operation:
00h → WDT,
0 → WDT prescaler,
1 → TO,
0 → PD
Status Affected:
TO, PD
Description:
The power-down status bit, PD is
cleared. Time-out status bit, TO
is set. Watchdog Timer and its
prescaler are cleared.
The processor is put into SLEEP
mode with the oscillator stopped.
RETURN
Status Affected:
None
Description:
Return from subroutine. The stack
is POPed and the top of the stack
(TOS) is loaded into the program
counter. This is a two-cycle
instruction.
© 2007 Microchip Technology Inc.
[ label ]
SLEEP
DS39597C-page 79
PIC16F72
SUBLW
Syntax:
Subtract W from Literal
[ label ]
SUBLW k
XORLW
Exclusive OR Literal with W
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operands:
0 ≤ k ≤ 255
Operation:
k - (W) → (W)
XORLW k
Operation:
(W) .XOR. k → (W)
Status Affected: C, DC, Z
Status Affected:
Z
Description:
The W register is subtracted (2’s
complement method) from the
eight-bit literal ‘k’. The result is
placed in the W register.
Description:
The contents of the W register
are XOR’ed with the eight-bit
literal ‘k’. The result is placed in
the W register.
SUBWF
Syntax:
Subtract W from f
[ label ]
SUBWF f,d
XORWF
Syntax:
[ label ] XORWF
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) - (W) → (destination)
Operation:
(W) .XOR. (f) → (destination)
Status Affected: C, DC, Z
Status Affected:
Z
Description:
Description:
Exclusive OR the contents of the
W register with register ‘f’. If
‘d’ = ‘0’, the result is stored in the
W register. If ‘d’ = ‘1’, the result is
stored back in register ‘f’.
Subtract (2’s complement method)
W register from register ‘f’. If
‘d’ = ‘0’, the result is stored in the W
register. If ‘d’ = ‘1’, the result is
stored back in register ‘f’.
SWAPF
Swap Nibbles in f
Syntax:
[ label ] SWAPF f,d
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f<3:0>) → (destination<7:4>),
(f<7:4>) → (destination<3:0>)
Status Affected:
None
Description:
The upper and lower nibbles of
register ‘f’ are exchanged. If
‘d’ = ‘0’, the result is placed in W
register. If ‘d’ = ‘1’, the result is
placed in register ‘f’.
DS39597C-page 80
Exclusive OR W with f
f,d
© 2007 Microchip Technology Inc.
PIC16F72
13.0
DEVELOPMENT SUPPORT
The PIC® microcontrollers are supported with a full
range of hardware and software development tools:
• Integrated Development Environment
- MPLAB® IDE Software
• Assemblers/Compilers/Linkers
- MPASMTM Assembler
- MPLAB C17 and MPLAB C18 C Compilers
- MPLINKTM Object Linker/
MPLIBTM Object Librarian
• Simulators
- MPLAB SIM Software Simulator
• Emulators
- MPLAB ICE 2000 In-Circuit Emulator
- ICEPIC™ In-Circuit Emulator
• In-Circuit Debugger
- MPLAB ICD
• Device Programmers
- PRO MATE® II Universal Device Programmer
- PICSTART® Plus Entry-Level Development
Programmer
• Low Cost Demonstration Boards
- PICDEMTM 1 Demonstration Board
- PICDEM 2 Demonstration Board
- PICDEM 3 Demonstration Board
- PICDEM 17 Demonstration Board
- KEELOQ® Demonstration Board
13.1
MPLAB Integrated Development
Environment Software
The MPLAB IDE software brings an ease of software
development previously unseen in the 8-bit microcontroller market. The MPLAB IDE is a Windows®-based
application that contains:
• An interface to debugging tools
- simulator
- programmer (sold separately)
- emulator (sold separately)
- in-circuit debugger (sold separately)
• A full-featured editor
• A project manager
• Customizable toolbar and key mapping
• A status bar
• On-line help
© 2007 Microchip Technology Inc.
The MPLAB IDE allows you to:
• Edit your source files (either assembly or ‘C’)
• One touch assemble (or compile) and download
to PIC emulator and simulator tools (automatically
updates all project information)
• Debug using:
- source files
- absolute listing file
- machine code
The ability to use MPLAB IDE with multiple debugging
tools allows users to easily switch from the costeffective simulator to a full-featured emulator with
minimal retraining.
13.2
MPASM Assembler
The MPASM assembler is a full-featured universal
macro assembler for all PIC MCU’s.
The MPASM assembler has a command line interface
and a Windows shell. It can be used as a stand-alone
application on a Windows 3.x or greater system, or it
can be used through MPLAB IDE. The MPASM assembler generates relocatable object files for the MPLINK
object linker, Intel® standard HEX files, MAP files to
detail memory usage and symbol reference, an absolute LST file that contains source lines and generated
machine code, and a COD file for debugging.
The MPASM assembler features include:
• Integration into MPLAB IDE projects.
• User-defined macros to streamline assembly
code.
• Conditional assembly for multi-purpose source
files.
• Directives that allow complete control over the
assembly process.
13.3
MPLAB C17 and MPLAB C18
C Compilers
The MPLAB C17 and MPLAB C18 Code Development
Systems are complete ANSI ‘C’ compilers for
Microchip’s PIC17CXXX and PIC18CXXX family of
microcontrollers, respectively. These compilers provide
powerful integration capabilities and ease of use not
found with other compilers.
For easier source level debugging, the compilers provide symbol information that is compatible with the
MPLAB IDE memory display.
DS39597C-page 81
PIC16F72
13.4
MPLINK Object Linker/
MPLIB Object Librarian
The MPLINK object linker combines relocatable
objects created by the MPASM assembler and the
MPLAB C17 and MPLAB C18 C compilers. It can also
link relocatable objects from pre-compiled libraries,
using directives from a linker script.
The MPLIB object librarian is a librarian for precompiled code to be used with the MPLINK object
linker. When a routine from a library is called from
another source file, only the modules that contain that
routine will be linked in with the application. This allows
large libraries to be used efficiently in many different
applications. The MPLIB object librarian manages the
creation and modification of library files.
The MPLINK object linker features include:
• Integration with MPASM assembler and MPLAB
C17 and MPLAB C18 C compilers.
• Allows all memory areas to be defined as sections
to provide link-time flexibility.
The MPLIB object librarian features include:
• Easier linking because single libraries can be
included instead of many smaller files.
• Helps keep code maintainable by grouping
related modules together.
• Allows libraries to be created and modules to be
added, listed, replaced, deleted or extracted.
13.5
MPLAB SIM Software Simulator
The MPLAB SIM software simulator allows code development in a PC-hosted environment by simulating the
PIC series microcontrollers on an instruction level. On
any given instruction, the data areas can be examined
or modified and stimuli can be applied from a file, or
user-defined key press, to any of the pins. The execution can be performed in single step, execute until
break, or trace mode.
13.6
MPLAB ICE High Performance
Universal In-Circuit Emulator with
MPLAB IDE
The MPLAB ICE universal in-circuit emulator is intended
to provide the product development engineer with a
complete microcontroller design tool set for PIC microcontrollers (MCUs). Software control of the MPLAB ICE
in-circuit emulator is provided by the MPLAB Integrated
Development Environment (IDE), which allows editing,
building, downloading and source debugging from a
single environment.
The MPLAB ICE 2000 is a full-featured emulator system with enhanced trace, trigger and data monitoring
features. Interchangeable processor modules allow the
system to be easily reconfigured for emulation of different processors. The universal architecture of the
MPLAB ICE in-circuit emulator allows expansion to
support new PIC microcontrollers.
The MPLAB ICE in-circuit emulator system has been
designed as a real-time emulation system, with
advanced features that are generally found on more
expensive development tools. The PC platform and
Microsoft® Windows environment were chosen to best
make these features available to you, the end user.
13.7
ICEPIC In-Circuit Emulator
The ICEPIC low cost, in-circuit emulator is a solution
for the Microchip Technology PIC16C5X, PIC16C6X,
PIC16C7X and PIC16CXXX families of 8-bit OneTime-Programmable (OTP) microcontrollers. The modular system can support different subsets of PIC16C5X
or PIC16CXXX products through the use of interchangeable personality modules, or daughter boards.
The emulator is capable of emulating without target
application circuitry being present.
The MPLAB SIM simulator fully supports symbolic debugging using the MPLAB C17 and the MPLAB C18 C compilers and the MPASM assembler. The software simulator
offers the flexibility to develop and debug code outside of
the laboratory environment, making it an excellent multiproject software development tool.
DS39597C-page 82
© 2007 Microchip Technology Inc.
PIC16F72
13.8
MPLAB ICD In-Circuit Debugger
Microchip's In-Circuit Debugger, MPLAB ICD, is a powerful, low cost, run-time development tool. This tool is
based on the FLASH PIC MCUs and can be used to
develop for this and other PIC microcontrollers. The
MPLAB ICD utilizes the in-circuit debugging capability
built into the FLASH devices. This feature, along with
Microchip's In-Circuit Serial ProgrammingTM protocol,
offers cost-effective in-circuit FLASH debugging from
the graphical user interface of the MPLAB Integrated
Development Environment. This enables a designer to
develop and debug source code by watching variables,
single-stepping and setting break points. Running at
full speed enables testing hardware in real-time.
13.9
PRO MATE II Universal Device
Programmer
The PRO MATE II universal device programmer is a
full-featured programmer, capable of operating in
stand-alone mode, as well as PC-hosted mode. The
PRO MATE II device programmer is CE compliant.
The PRO MATE II device programmer has programmable VDD and VPP supplies, which allow it to verify
programmed memory at VDD min and VDD max for maximum reliability. It has an LCD display for instructions
and error messages, keys to enter commands and a
modular detachable socket assembly to support various
package types. In stand-alone mode, the PRO MATE II
device programmer can read, verify, or program PIC
devices. It can also set code protection in this mode.
13.10 PICSTART Plus Entry Level
Development Programmer
The PICSTART Plus development programmer is an
easy-to-use, low cost, prototype programmer. It connects to the PC via a COM (RS-232) port. MPLAB
Integrated Development Environment software makes
using the programmer simple and efficient.
The PICSTART Plus development programmer supports all PIC devices with up to 40 pins. Larger pin
count devices, such as the PIC16C92X and
PIC17C76X, may be supported with an adapter socket.
The PICSTART Plus development programmer is CE
compliant.
© 2007 Microchip Technology Inc.
13.11 PICDEM 1 Low Cost PIC
Demonstration Board
The PICDEM 1 demonstration board is a simple board
which demonstrates the capabilities of several of
Microchip’s microcontrollers. The microcontrollers supported are: PIC16C5X (PIC16C54 to PIC16C58A),
PIC16C61, PIC16C62X, PIC16C71, PIC16C8X,
PIC17C42, PIC17C43 and PIC17C44. All necessary
hardware and software is included to run basic demo
programs. The user can program the sample microcontrollers provided with the PICDEM 1 demonstration
board on a PRO MATE II device programmer, or a
PICSTART Plus development programmer, and easily
test firmware. The user can also connect the
PICDEM 1 demonstration board to the MPLAB ICE incircuit emulator and download the firmware to the emulator for testing. A prototype area is available for the
user to build some additional hardware and connect it
to the microcontroller socket(s). Some of the features
include an RS-232 interface, a potentiometer for simulated analog input, push button switches and eight
LEDs connected to PORTB.
13.12 PICDEM 2 Low Cost PIC16CXX
Demonstration Board
The PICDEM 2 demonstration board is a simple demonstration board that supports the PIC16C62,
PIC16C64, PIC16C65, PIC16C73 and PIC16C74
microcontrollers. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample
microcontrollers provided with the PICDEM 2 demonstration board on a PRO MATE II device programmer,
or a PICSTART Plus development programmer, and
easily test firmware. The MPLAB ICE in-circuit emulator may also be used with the PICDEM 2 demonstration
board to test firmware. A prototype area has been provided to the user for adding additional hardware and
connecting it to the microcontroller socket(s). Some of
the features include a RS-232 interface, push button
switches, a potentiometer for simulated analog input, a
serial EEPROM to demonstrate usage of the I2CTM bus
and separate headers for connection to an LCD
module and a keypad.
DS39597C-page 83
PIC16F72
13.13 PICDEM 3 Low Cost PIC16CXXX
Demonstration Board
The PICDEM 3 demonstration board is a simple demonstration board that supports the PIC16C923 and
PIC16C924 in the PLCC package. It will also support
future 44-pin PLCC microcontrollers with an LCD Module. All the necessary hardware and software is
included to run the basic demonstration programs. The
user can program the sample microcontrollers provided with the PICDEM 3 demonstration board on a
PRO MATE II device programmer, or a PICSTART Plus
development programmer with an adapter socket, and
easily test firmware. The MPLAB ICE in-circuit emulator may also be used with the PICDEM 3 demonstration
board to test firmware. A prototype area has been provided to the user for adding hardware and connecting it
to the microcontroller socket(s). Some of the features
include a RS-232 interface, push button switches, a
potentiometer for simulated analog input, a thermistor
and separate headers for connection to an external
LCD module and a keypad. Also provided on the
PICDEM 3 demonstration board is a LCD panel, with 4
commons and 12 segments, that is capable of displaying time, temperature and day of the week. The
PICDEM 3 demonstration board provides an additional
RS-232 interface and Windows software for showing
the demultiplexed LCD signals on a PC. A simple serial
interface allows the user to construct a hardware
demultiplexer for the LCD signals.
DS39597C-page 84
13.14 PICDEM 17 Demonstration Board
The PICDEM 17 demonstration board is an evaluation
board that demonstrates the capabilities of several
Microchip microcontrollers, including PIC17C752,
PIC17C756A, PIC17C762 and PIC17C766. All necessary hardware is included to run basic demo programs,
which are supplied on a 3.5-inch disk. A programmed
sample is included and the user may erase it and
program it with the other sample programs using the
PRO MATE II device programmer, or the PICSTART
Plus development programmer, and easily debug and
test the sample code. In addition, the PICDEM 17 demonstration board supports downloading of programs to
and executing out of external FLASH memory on board.
The PICDEM 17 demonstration board is also usable
with the MPLAB ICE in-circuit emulator, or the
PICMASTER emulator and all of the sample programs
can be run and modified using either emulator. Additionally, a generous prototype area is available for user
hardware.
13.15 KEELOQ Evaluation and
Programming Tools
KEELOQ evaluation and programming tools support
Microchip’s HCS Secure Data Products. The HCS evaluation kit includes a LCD display to show changing
codes, a decoder to decode transmissions and a programming interface to program test transmitters.
© 2007 Microchip Technology Inc.
Software Tools
Programmers Debugger Emulators
PIC12CXXX
PIC14000
PIC16C5X
PIC16C6X
PIC16CXXX
PIC16F62X
PIC16C7X
9
9
9
9
9
9
© 2007 Microchip Technology Inc.
9
9
9
†
†
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
9
MCP2510
* Contact the Microchip Technology Inc. web site at www.microchip.com for information on how to use the MPLAB® ICD In-Circuit Debugger (DV164001) with PIC16C62, 63, 64, 65, 72, 73, 74, 76, 77.
** Contact Microchip Technology Inc. for availability date.
† Development tool is available on select devices.
MCP2510 CAN Developer’s Kit
9
13.56 MHz Anticollision
microIDTM Developer’s Kit
9
125 kHz Anticollision microIDTM
Developer’s Kit
9
125 kHz microIDTM
Developer’s Kit
MCRFXXX
microIDTM Programmer’s Kit
9
†
9**
9
9*
9
9
9
9
9
9
9
9
9**
9**
PIC18FXXX
9
24CXX/
25CXX/
93CXX
KEELOQ® Transponder Kit
9
9
9
9
9
9
9
9
9
HCSXXX
KEELOQ® Evaluation Kit
PICDEMTM 17 Demonstration
Board
PICDEMTM 14A Demonstration
Board
PICDEMTM 3 Demonstration
Board
PICDEMTM 2 Demonstration
Board
PICDEMTM 1 Demonstration
Board
9
9
PRO MATE® II
Universal Device Programmer
9
9
9
9
PICSTART® Plus Entry Level
Development Programmer
9
9
9*
9
9
MPLAB® ICD In-Circuit
Debugger
9
9
9
9
9
9
9
9
ICEPICTM In-Circuit Emulator
9
9
PIC16C7XX
9
9
9
PIC16C8X/
PIC16F8X
9
9
9
PIC16F8XX
9
9
9
PIC16C9XX
MPLAB® ICE In-Circuit Emulator
9
9
PIC17C4X
9
9
9
PIC17C7XX
MPASMTM Assembler/
MPLINKTM Object Linker
9
PIC18CXX2
MPLAB® C18 C Compiler
MPLAB® C17 C Compiler
TABLE 13-1:
Demo Boards and Eval Kits
MPLAB® Integrated
Development Environment
PIC16F72
DEVELOPMENT TOOLS FROM MICROCHIP
DS39597C-page 85
PIC16F72
NOTES:
DS39597C-page 86
© 2007 Microchip Technology Inc.
PIC16F72
14.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings †
Ambient temperature under bias................................................................................................................ -55 to +125°C
Storage temperature .............................................................................................................................. -65°C to +150°C
Voltage on any pin with respect to VSS (except VDD, MCLR. and RA4) ......................................... -0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS ............................................................................................................ -0.3 to +6.5V
Voltage on MCLR with respect to VSS (Note 2) ..............................................................................................0 to +13.5V
Voltage on RA4 with respect to Vss ...................................................................................................................0 to +12V
Total power dissipation (Note 1) ...............................................................................................................................1.0W
Maximum current out of VSS pin ...........................................................................................................................300 mA
Maximum current into VDD pin ..............................................................................................................................250 mA
Input clamp current, IIK (VI < 0 or VI > VDD)..................................................................................................................... ± 20 mA
Output clamp current, IOK (VO < 0 or VO > VDD) ............................................................................................................. ± 20 mA
Maximum output current sunk by any I/O pin..........................................................................................................25 mA
Maximum output current sourced by any I/O pin ....................................................................................................25 mA
Maximum current sunk by PORTA, PORTB..........................................................................................................200 mA
Maximum current sourced by PORTA, PORTB ....................................................................................................200 mA
Maximum current sunk by PORTC .......................................................................................................................200 mA
Maximum current sourced by PORTC ..................................................................................................................200 mA
Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - ∑ IOH} + ∑ {(VDD - VOH) x IOH} + ∑(VOl x IOL)
2: Voltage spikes at the MCLR pin may cause unpredictable results. A series resistor of greater than 1 kΩ
should be used to pull MCLR to VDD, rather than tying the pin directly to VDD.
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
© 2007 Microchip Technology Inc.
DS39597C-page 87
PIC16F72
FIGURE 14-1:
PIC16F72 (INDUSTRIAL, EXTENDED) VOLTAGE-FREQUENCY GRAPH
6.0V
5.5V
5.0V
Voltage
4.5V
4.0V
3.5V
3.0V
2.5V
2.0V
16 MHz
20 MHz
Frequency
FIGURE 14-2:
PIC16LF72 (INDUSTRIAL) VOLTAGE-FREQUENCY GRAPH
6.0V
5.5V
Voltage
5.0V
4.5V
4.0V
3.5V
3.0V
2.5V
2.0V
4 MHz
10 MHz
Frequency
FMAX = (12 MHz/V) (VDDAPPMIN - 2.5V) + 4 MHz
Note 1: VDDAPPMIN is the minimum voltage of the PIC® device in the application.
Note 2: FMAX has a maximum frequency of 10 MHz.
DS39597C-page 88
© 2007 Microchip Technology Inc.
PIC16F72
14.1
DC Characteristics: PIC16F72 (Industrial, Extended)
PIC16LF72 (Industrial)
PIC16LF72
(Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
PIC16F72
(Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Param
No.
Sym
VDD
Characteristic
Min
Typ† Max Units
Supply Voltage
D001
D001
D001A
PIC16LF72
2.0
2.5
2.2
—
—
—
5.5
5.5
5.5
V
V
V
A/D not used, -40°C to +85°C
A/D in use, -40°C to +85°C
A/D in use, 0°C to +85°C
PIC16F72
4.0
VBOR*
—
—
5.5
5.5
V
V
All configurations
BOR enabled (Note 7)
D002*
VDR
RAM Data Retention
Voltage (Note 1)
—
1.5
—
V
D003
VPOR
VDD Start Voltage to
ensure internal Power-on
Reset signal
—
VSS
—
V
D004*
SVDD
VDD Rise Rate to ensure
internal Power-on Reset
signal
0.05
—
—
D005
VBOR
Brown-out Reset Voltage
3.65
4.0
4.35
*
†
Note 1:
2:
3:
4:
5:
6:
7:
Conditions
See section on Power-on Reset for details
V/ms See section on Power-on Reset for details
V
BOREN bit in configuration word enabled
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
This is the limit to which VDD can be lowered without losing RAM data.
The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an
impact on the current consumption. The test conditions for all IDD measurements in active Operation mode
are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
For RC osc configuration, current through REXT is not included. The current through the resistor can be
estimated by the formula Ir = VDD/2REXT (mA) with REXT in kΩ.
Timer1 oscillator (when enabled) adds approximately 20 μA to the specification. This value is from
characterization and is for design guidance only. This is not tested.
The Δ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
When BOR is enabled, the device will operate correctly until the VBOR voltage trip point is reached.
© 2007 Microchip Technology Inc.
DS39597C-page 89
PIC16F72
14.1
DC Characteristics: PIC16F72 (Industrial, Extended)
PIC16LF72 (Industrial) (Continued)
PIC16LF72
(Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
PIC16F72
(Industrial, Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Param
No.
Sym
IDD
Characteristic
PIC16LF72
D010A
D010
PIC16F72
D013
ΔIBOR Brown-out Reset Current
(Note 6)
IPD
Typ† Max Units
Conditions
Supply Current (Notes 2, 5)
D010
D015*
Min
—
0.4
2.0
mA
XT, RC osc configuration
FOSC = 4 MHz, VDD = 3.0V (Note 4)
LP osc configuration
FOSC = 32 kHz, VDD = 3.0V, WDT disabled
—
25
48
μA
-
0.9
4
mA
—
5.2
15
mA
—
25
200
μA
BOR enabled, VDD = 5.0V
XT, RC osc configuration
FOSC = 4 MHz, VDD = 5.5V (Note 4)
HS osc configuration
FOSC = 20 MHz, VDD = 5.5V
Power-down Current (Notes 3, 5)
D020
D021
PIC16LF72
—
—
2.0
0.1
30
5
μA
μA
VDD = 3.0V, WDT enabled, -40°C to +85°C
VDD = 3.0V, WDT disabled, -40°C to +85°C
D020
D021
PIC16F72
—
5.0
0.1
42
19
μA
μA
VDD = 4.0V, WDT enabled, -40°C to +85°C
VDD = 4.0V, WDT disabled, -40°C to +85°C
ΔIBOR Brown-out Reset Current
(Note 6)
—
25
200
μA
BOR enabled, VDD = 5.0V
D023*
*
†
Note 1:
2:
3:
4:
5:
6:
7:
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
This is the limit to which VDD can be lowered without losing RAM data.
The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin
loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an
impact on the current consumption. The test conditions for all IDD measurements in active Operation mode
are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD
MCLR = VDD; WDT enabled/disabled as specified.
The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is
measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD and VSS.
For RC osc configuration, current through REXT is not included. The current through the resistor can be
estimated by the formula Ir = VDD/2REXT (mA) with REXT in kΩ.
Timer1 oscillator (when enabled) adds approximately 20 μA to the specification. This value is from
characterization and is for design guidance only. This is not tested.
The Δ current is the additional current consumed when this peripheral is enabled. This current should be
added to the base IDD or IPD measurement.
When BOR is enabled, the device will operate correctly until the VBOR voltage trip point is reached.
DS39597C-page 90
© 2007 Microchip Technology Inc.
PIC16F72
14.2
DC Characteristics: PIC16F72 (Industrial, Extended)
PIC16LF72 (Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Operating voltage VDD range as described in DC Specification,
Section 14.1.
DC CHARACTERISTICS
Param
No.
Sym
VIL
D030
D030A
D031
Characteristic
Input Low Voltage
I/O ports
with TTL buffer
with Schmitt Trigger buffer
D032
D033
VIH
D040
D040A
D041
MCLR, OSC1 (in RC mode)
OSC1 (in XT and LP mode)
OSC1 (in HS mode)
Input High Voltage
I/O ports
with TTL buffer
with Schmitt Trigger buffer
D042
D042A
Min
Typ†
Max
Units
VSS
VSS
VSS
—
—
—
0.15 VDD
0.8V
0.2 VDD
V
V
V
VSS
VSS
VSS
—
—
—
0.2 VDD
0.3V
0.3 VDD
V
V
V
(Note 1)
(Note 1)
2.0
0.25 VDD + 0.8V
0.8 VDD
—
—
—
VDD
VDD
VDD
V
V
V
4.5V ≤ VDD ≤ 5.5V
For entire VDD range
For entire VDD range
—
—
—
—
250
VDD
VDD
VDD
VDD
400
V
V
V
V
μA
—
±1
μA
Vss ≤ VPIN ≤ VDD, Pin at
hi-impedance
—
—
±5
±5
μA
μA
Vss ≤ VPIN ≤ VDD
Vss ≤ VPIN ≤ VDD, XT, HS
and LP osc configuration
D060
MCLR
0.8 VDD
OSC1 (in XT and LP mode)
1.6V
OSC1 (in HS mode)
0.7 VDD
OSC1 (in RC mode)
0.9 VDD
PORTB Weak Pull-up Current
50
Input Leakage Current (Notes 2, 3)
I/O ports
—
D061
D063
MCLR, RA4/T0CKI
OSC1
D043
D070
IPURB
IIL
—
—
Conditions
For entire VDD range
4.5V ≤ VDD ≤ 5.5V
(Note 1)
(Note 1)
VDD = 5V, VPIN = VSS
*
†
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKI pin is a Schmitt Trigger input. It is not recommended that the
PIC16F72 be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
© 2007 Microchip Technology Inc.
DS39597C-page 91
PIC16F72
14.2
DC Characteristics: PIC16F72 (Industrial, Extended)
PIC16LF72 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Operating voltage VDD range as described in DC Specification,
Section 14.1.
DC CHARACTERISTICS
Param
No.
Sym
Min
Typ†
Max
Units
D080
Output Low Voltage
I/O ports
—
—
0.6
V
D083
OSC2/CLKO (RC osc config)
—
—
0.6
V
D090
Output High Voltage
I/O ports (Note 3)
VDD - 0.7
—
—
V
D092
OSC2/CLKO (RC osc config)
VDD - 0.7
—
—
V
—
12
V
—
15
pF
—
50
pF
VOL
VOH
D150*
VOD
D100
COSC2
D101
CIO
Characteristic
Open Drain High Voltage
—
Capacitive Loading Specs on Output Pins
OSC2 pin
—
All I/O pins and OSC2
(in RC mode)
—
Conditions
IOL = 8.5 mA, VDD = 4.5V,
-40°C to +85°C
IOL = 1.6 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -3.0 mA, VDD = 4.5V,
-40°C to +85°C
IOH = -1.3 mA, VDD = 4.5V,
-40°C to +85°C
RA4 pin
In XT, HS and LP modes
when external clock is used
to drive OSC1
—
—
400
pF
SCL, SDA in I2C mode
Program FLASH Memory
D130 EP
Endurance
100
1000
—
E/W 25°C at 5V
D131 VPR
VDD for read
2.0
—
5.5
V
* These parameters are characterized but not tested.
† Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In RC oscillator configuration, the OSC1/CLKI pin is a Schmitt Trigger input. It is not recommended that the
PIC16F72 be driven with external clock in RC mode.
2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as current sourced by the pin.
D102
CB
DS39597C-page 92
© 2007 Microchip Technology Inc.
PIC16F72
14.3
Timing Parameter Symbology
The timing parameter symbols have been created following one of the following formats:
1. TppS2ppS
3. TCC:ST
(I2C specifications only)
2. TppS
4. Ts
(I2C specifications only)
T
F
Frequency
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
ck
CLKO
cs
CS
di
SDI
do
SDO
dt
Data in
io
I/O port
mc
MCLR
Uppercase letters and their meanings:
S
F
Fall
H
High
I
Invalid (Hi-impedance)
L
Low
I2C only
AA
BUF
output access
Bus free
TCC:ST (I2C specifications only)
CC
HD
Hold
ST
DAT
DATA input hold
STA
START condition
FIGURE 14-3:
T
Time
osc
rd
rw
sc
ss
t0
t1
wr
OSC1
RD
RD or WR
SCK
SS
T0CKI
T1CKI
WR
P
R
V
Z
Period
Rise
Valid
Hi-impedance
High
Low
High
Low
SU
Setup
STO
STOP condition
LOAD CONDITIONS
Load Condition 1
Load Condition 2
VDD/2
RL
CL
Pin
VSS
CL
Pin
VSS
RL = 464Ω
CL = 50 pF
15 pF
for all pins except OSC2
for OSC2 output
© 2007 Microchip Technology Inc.
DS39597C-page 93
PIC16F72
FIGURE 14-4:
EXTERNAL CLOCK TIMING
Q4
Q1
Q2
Q3
Q4
Q1
OSC1
1
3
4
3
4
2
CLKO
TABLE 14-1:
Parameter
No.
EXTERNAL CLOCK TIMING REQUIREMENTS
Symbol
FOSC
Characteristic
External CLKI Frequency
(Note 1)
Oscillator Frequency
(Note 1)
1
TOSC
External CLKI Period
(Note 1)
Oscillator Period
(Note 1)
Min
Typ†
Max
Units
Conditions
DC
—
1
MHz XT Osc mode
DC
—
20
MHz HS Osc mode
DC
—
32
kHz
DC
—
4
MHz RC osc mode
LP Osc mode
0.1
—
4
MHz XT Osc mode
4
5
—
—
20
200
MHz HS Osc mode
kHz LP Osc mode
1000
—
—
ns
XT Osc mode
50
—
—
ns
HS Osc mode
5
—
—
ms
LP Osc mode
250
—
—
ns
RC Osc mode
250
—
10,000
ns
XT Osc mode
50
—
250
ns
HS Osc mode
5
—
—
ms
LP Osc mode
2
TCY
Instruction Cycle Time
(Note 1)
200
TCY
DC
ns
TCY = 4/FOSC
3
TosL,
TosH
External Clock in (OSC1)
High or Low Time
500
—
—
ns
XT oscillator
4
TosR,
TosF
External Clock in (OSC1)
Rise or Fall Time
2.5
—
—
ms
LP oscillator
15
—
—
ns
HS oscillator
—
—
25
ns
XT oscillator
—
—
50
ns
LP oscillator
—
—
15
ns
HS oscillator
†
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are
based on characterization data for that particular oscillator type under standard operating conditions with
the device executing code. Exceeding these specified limits may result in an unstable oscillator operation
and/or higher than expected current consumption. All devices are tested to operate at "min" values with an
external clock applied to the OSC1/CLKI pin. When an external clock input is used, the "max" cycle time
limit is "DC" (no clock) for all devices.
DS39597C-page 94
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 14-5:
CLKO AND I/O TIMING
Q1
Q4
Q2
Q3
OSC1
11
10
CLKO
13
14
19
12
18
16
I/O Pin
(Input)
15
17
I/O Pin
(Output)
New Value
Old Value
20, 21
Note: Refer to Figure 14-3 for load conditions.
TABLE 14-2:
CLKO AND I/O TIMING REQUIREMENTS
Param
No.
Symbol
10*
TosH2ckL
OSC1↑ to CLKO↓
—
75
200
ns
(Note 1)
11*
TosH2ckH OSC1↑ to CLKO↑
—
75
200
ns
(Note 1)
(Note 1)
Characteristic
Min
Typ†
Max
Units Conditions
12*
TckR
CLKO rise time
—
35
100
ns
13*
TckF
CLKO fall time
—
35
100
ns
(Note 1)
14*
TckL2ioV
CLKO↓ to Port out valid
—
—
0.5 TCY + 20
ns
(Note 1)
15*
TioV2ckH
Port in valid before CLKO↑
TOSC + 200
—
—
ns
(Note 1)
(Note 1)
16*
TckH2ioI
Port in hold after CLKO↑
0
—
—
ns
17*
TosH2ioV
OSC1↑ (Q1 cycle) to Port out valid
—
100
255
ns
18*
TosH2ioI
OSC1↑ (Q2 cycle) to
Port input invalid (I/O in
hold time)
Standard (F)
100
—
—
ns
Extended (LF)
200
—
—
ns
—
ns
ns
19*
TioV2osH
Port input valid to OSC1↑ (I/O in setup time)
0
—
20*
TioR
Port output rise time
21*
TioF
Port output fall time
Standard (F)
—
10
40
Extended (LF)
—
—
145
ns
Standard (F)
—
10
40
ns
Extended (LF)
—
—
145
ns
22††*
TINP
INT pin high or low time
TCY
—
—
ns
23††*
TRBP
RB7:RB4 change INT high or low time
TCY
—
—
ns
*
†
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.
†† These parameters are asynchronous events, not related to any internal clock edges.
Note 1: Measurements are taken in RC mode, where CLKO output is 4 x TOSC.
© 2007 Microchip Technology Inc.
DS39597C-page 95
PIC16F72
FIGURE 14-6:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP
TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Time-out
Internal
RESET
Watchdog
Timer
Reset
31
34
34
I/O Pins
Note: Refer to Figure 14-3 for load conditions.
FIGURE 14-7:
BROWN-OUT RESET TIMING
VBOR
VDD
35
TABLE 14-3:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER,
AND BROWN-OUT RESET REQUIREMENTS
Parameter No. Symbol
Characteristic
Min
Typ†
Max
Units
Conditions
30
TmcL
MCLR Pulse Width (low)
2
—
—
μs
VDD = 5V, -40°C to +85°C
31*
TWDT
Watchdog Timer Time-out Period
(No Prescaler)
7
18
33
ms
VDD = 5V, -40°C to +85°C
32
TOST
Oscillation Start-up Timer Period
—
1024 TOSC
—
—
TOSC = OSC1 period
33*
TPWRT
Power-up Timer Period
28
72
132
ms
VDD = 5V, -40°C to +85°C
34
TIOZ
I/O Hi-impedance from MCLR Low
or Watchdog Timer Reset
—
—
2.1
μs
35
TBOR
Brown-out Reset Pulse Width
100
—
—
μs
VDD ≤ VBOR (D005)
* These parameters are characterized but not tested.
† Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not tested.
DS39597C-page 96
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 14-8:
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
RA4/T0CKI
41
40
42
RC0/T1OSO/T1CKI
46
45
47
48
TMR0 or
TMR1
Note: Refer to Figure 14-3 for load conditions.
TABLE 14-4:
Param
No.
40*
TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Symbol
Tt0H
Characteristic
T0CKI High Pulse Width
No Prescaler
With Prescaler
41*
Tt0L
T0CKI Low Pulse Width
No Prescaler
With Prescaler
42*
Tt0P
T0CKI Period
No Prescaler
With Prescaler
45*
Tt1H
46*
Tt1L
47*
Tt1P
T1CKI Input
Period
48
Units
0.5 TCY + 20
—
—
ns
10
—
—
ns
0.5 TCY + 20
—
—
ns
10
—
—
ns
Must also meet
parameter 42
TCY + 40
—
—
ns
Greater of:
20 or TCY + 40
N
—
—
ns
N = prescale value
(2, 4, ..., 256)
Must also meet
parameter 47
—
—
ns
—
—
ns
25
—
—
ns
Asynchronous
Standard(F)
30
—
—
ns
Extended(LF)
50
—
—
ns
0.5 TCY + 20
—
—
ns
Synchronous,
Standard(F)
Prescaler = 2,4,8 Extended(LF)
15
—
—
ns
25
—
—
ns
Asynchronous
Standard(F)
30
—
—
ns
Extended(LF)
50
—
—
ns
Standard(F)
Greater of:
30 or TCY + 40
N
—
—
ns
Extended(LF)
Greater of:
50 or TCY + 40
N
Synchronous, Prescaler = 1
Synchronous
Must also meet
parameter 47
N = prescale value
(1, 2, 4, 8)
N = prescale value
(1, 2, 4, 8)
Standard(F)
60
—
—
Extended(LF)
100
—
—
ns
DC
—
200
kHz
2 TOSC
—
7 TOSC
—
Timer1 Oscillator Input Frequency Range
(oscillator enabled by setting bit T1OSCEN)
Conditions
Must also meet
parameter 42
15
TCKEZtmr1 Delay from External Clock Edge to Timer Increment
*
†
Max
0.5 TCY + 20
Asynchronous
Ft1
Typ†
Synchronous,
Standard(F)
Prescaler = 2,4,8 Extended(LF)
T1CKI High Time Synchronous, Prescaler = 1
T1CKI Low Time
Min
ns
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.
© 2007 Microchip Technology Inc.
DS39597C-page 97
PIC16F72
FIGURE 14-9:
CAPTURE/COMPARE/PWM TIMINGS (CCP1 )
RC2/CCP1
(Capture Mode)
50
51
52
RC2/CCP1
(Compare or PWM Mode)
53
54
Note: Refer to Figure 14-3 for load conditions.
TABLE 14-5:
CAPTURE/COMPARE/PWM REQUIREMENTS (CCP1)
Param
Symbol
No.
50*
TccL
Characteristic
Min
No Prescaler
0.5 TCY + 20
—
—
ns
Standard(F)
10
—
—
ns
Extended(LF)
20
—
—
ns
CCP1 input high No Prescaler
time
Standard(F)
With Prescaler
Extended(LF)
0.5 TCY + 20
—
—
ns
10
—
—
ns
20
—
—
ns
3 TCY + 40
N
—
—
ns
CCP1 input low
time
With Prescaler
51*
TccH
Typ† Max Units
52*
TccP
CCP1 input period
53*
TccR
CCP1 output rise time
Standard(F)
—
10
25
ns
Extended(LF)
—
25
50
ns
54*
TccF
CCP1 output fall time
Standard(F)
—
10
25
ns
Extended(LF)
—
25
45
ns
*
†
Conditions
N = prescale
value (1,4 or 16)
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
DS39597C-page 98
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 14-10:
SPI MASTER MODE TIMING (CKE = 0, SMP = 0)
SS
70
SCK
(CKP = 0)
71
72
78
79
79
78
SCK
(CKP = 1)
80
Bit6 - - - - - -1
MSb
SDO
LSb
75, 76
SDI
MSb In
Bit6 - - - -1
LSb In
74
73
Note: Refer to Figure 14-3 for load conditions.
FIGURE 14-11:
SPI MASTER MODE TIMING (CKE = 1, SMP = 1)
SS
81
SCK
(CKP = 0)
71
72
79
73
SCK
(CKP = 1)
80
78
SDO
MSb
Bit6 - - - - - -1
LSb
Bit6 - - - -1
LSb In
75, 76
SDI
MSb In
74
Note: Refer to Figure 14-3 for load conditions.
© 2007 Microchip Technology Inc.
DS39597C-page 99
PIC16F72
FIGURE 14-12:
SPI SLAVE MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
83
71
72
78
79
79
78
SCK
(CKP = 1)
80
MSb
SDO
LSb
Bit6 - - - - - -1
77
75, 76
SDI
MSb In
Bit6 - - - -1
LSb In
74
73
Note: Refer to Figure 14-3 for load conditions.
FIGURE 14-13:
SPI SLAVE MODE TIMING (CKE = 1)
82
SS
SCK
(CKP = 0)
70
83
71
72
SCK
(CKP = 1)
80
SDO
MSb
Bit6 - - - - - -1
LSb
75, 76
SDI
MSb In
77
Bit6 - - - -1
LSb In
74
Note: Refer to Figure 14-3 for load conditions.
DS39597C-page 100
© 2007 Microchip Technology Inc.
PIC16F72
TABLE 14-6:
Param
No.
SPI MODE REQUIREMENTS
Symbol
Characteristic
Min
Typ†
Max Units Conditions
TCY
—
—
ns
70*
TssL2scH,
TssL2scL
SS↓ to SCK↓ or SCK↑ input
71*
TscH
SCK input high time (Slave mode)
TCY + 20
—
—
ns
72*
TscL
SCK input low time (Slave mode)
TCY + 20
—
—
ns
73*
TdiV2scH,
TdiV2scL
Setup time of SDI data input to SCK edge
100
—
—
ns
74*
TscH2diL,
TscL2diL
Hold time of SDI data input to SCK edge
100
—
—
ns
75*
TdoR
SDO data output rise time
—
—
10
25
25
50
ns
ns
76*
TdoF
SDO data output fall time
—
10
25
ns
77*
TssH2doZ
SS↑ to SDO output hi-impedance
10
—
50
ns
78*
TscR
SCK output rise time
(Master mode)
—
—
10
25
25
50
ns
ns
79*
TscF
SCK output fall time (Master mode)
—
10
25
ns
80*
TscH2doV, SDO data output valid after
TscL2doV SCK edge
—
—
—
—
50
145
ns
ns
81*
TdoV2scH, SDO data output setup to SCK edge
TdoV2scL
TCY
—
—
ns
82*
TssL2doV
—
—
50
ns
83*
TscH2ssH, SS ↑ after SCK edge
TscL2ssH
1.5 TCY + 40
—
—
ns
*
†
Standard(F)
Extended(LF)
Standard(F)
Extended(LF)
Standard(F)
Extended(LF)
SDO data output valid after SS↓ edge
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
I2C BUS START/STOP BITS TIMING
FIGURE 14-14:
SCL
91
90
93
92
SDA
START
Condition
STOP
Condition
Note: Refer to Figure 14-3 for load conditions.
© 2007 Microchip Technology Inc.
DS39597C-page 101
PIC16F72
TABLE 14-7:
Param
No.
90*
I2C BUS START/STOP BITS REQUIREMENTS
Symbol
TSU:STA
91*
THD:STA
92*
TSU:STO
93
*
THD:STO
Characteristic
Min Typ Max Units
START condition
100 kHz mode
4700
—
—
Setup time
400 kHz mode
600
—
—
START condition
100 kHz mode
4000
—
—
Hold time
400 kHz mode
600
—
—
STOP condition
100 kHz mode
4700
—
—
Setup time
400 kHz mode
600
—
—
STOP condition
100 kHz mode
4000
—
—
Hold time
400 kHz mode
600
—
—
Conditions
ns
Only relevant for Repeated
START condition
ns
After this period, the first clock
pulse is generated
ns
ns
These parameters are characterized but not tested.
FIGURE 14-15:
I2C BUS DATA TIMING
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
Note: Refer to Figure 14-3 for load conditions.
DS39597C-page 102
© 2007 Microchip Technology Inc.
PIC16F72
TABLE 14-8:
Param
No.
100*
I2C BUS DATA REQUIREMENTS
Symbol
THIGH
Characteristic
Clock High Time
Min
Max
Units
100 kHz mode
4.0
—
μs
Device must operate at a
minimum of 1.5 MHz
400 kHz mode
0.6
—
μs
Device must operate at a
minimum of 10 MHz
1.5 TCY
—
100 kHz mode
4.7
—
μs
Device must operate at a
minimum of 1.5 MHz
400 kHz mode
1.3
—
μs
Device must operate at a
minimum of 10 MHz
SSP Module
101*
TLOW
Clock Low Time
1.5 TCY
—
—
1000
ns
20 + 0.1 CB
300
ns
100 kHz mode
—
300
ns
400 kHz mode
20 + 0.1 CB
300
ns
CB is specified to be from
10 - 400 pF
START Condition
Setup Time
100 kHz mode
4.7
—
μs
400 kHz mode
0.6
—
μs
Only relevant for
Repeated START
condition
START Condition
Hold Time
100 kHz mode
4.0
—
μs
400 kHz mode
0.6
—
μs
Data Input Hold
Time
100 kHz mode
0
—
ns
400 kHz mode
0
0.9
μs
Data Input Setup
Time
100 kHz mode
250
—
ns
400 kHz mode
100
—
ns
STOP Condition
Setup Time
100 kHz mode
4.7
—
μs
400 kHz mode
0.6
—
μs
Output Valid from
Clock
100 kHz mode
—
3500
ns
400 kHz mode
—
—
ns
100 kHz mode
4.7
—
μs
400 kHz mode
1.3
—
μs
—
400
pF
SSP Module
102*
103*
90*
91*
106*
107*
92*
109*
110*
TR
TF
TSU:STA
THD:STA
THD:DAT
TSU:DAT
TSU:STO
TAA
TBUF
CB
Conditions
SDA and SCL Rise 100 kHz mode
Time
400 kHz mode
SDA and SCL Fall
Time
Bus Free Time
Bus Capacitive Loading
CB is specified to be from
10 - 400 pF
After this period, the first
clock pulse is generated
(Note 2)
(Note 1)
Time the bus must be free
before a new transmission
can start
* These parameters are characterized but not tested.
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region
(min. 300 ns) of the falling edge of SCL to avoid unintended generation of START or STOP conditions.
2: A Fast mode (400 kHz) I2C bus device can be used in a Standard mode (100 kHz) I2C bus system, but the
requirement TSU:DAT ≥ 250 ns must then be met. This will automatically be the case if the device does not
stretch the LOW period of the SCL signal. If such a device does stretch the LOW period of the SCL signal,
it must output the next data bit to the SDA line TR max.+TSU:DAT = 1000 + 250 = 1250 ns (according to the
Standard mode I2C bus specification), before the SCL line is released.
© 2007 Microchip Technology Inc.
DS39597C-page 103
PIC16F72
TABLE 14-9:
Param
No.
A01
A/D CONVERTER CHARACTERISTICS: PIC16F72 (INDUSTRIAL)
PIC16LF72 (INDUSTRIAL)
Sym
NR
Characteristic
Resolution
Min
Typ†
Max
Units
Conditions
PIC16F72
—
—
8 bits
bit
VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
PIC16LF72
—
—
8 bits
bit
VREF = VDD = 2.2V
A02
EABS
Total Absolute Error
—
—
<±1
LSb VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A03
EIL
Integral Linearity Error
—
—
<±1
LSb VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A04
EDL
Differential Linearity Error
—
—
<±1
LSb VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A05
EFS
Full Scale Error
—
—
<±1
LSb VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A06
EOFF
Offset Error
—
—
<±1
LSb VREF = VDD = 5.12V,
VSS ≤ VAIN ≤ VREF
A10
—
Monotonicity (Note 3)
—
guaranteed
—
—
VSS ≤ VAIN ≤ VREF
A20
VREF
Reference Voltage
2.5
2.2
—
—
VDD+0.3
VDD+0.3
V
V
-40°C to +85°C
0°C to +85°C
A25
VAIN
Analog Input Voltage
VSS - 0.3
—
VREF + 0.3
V
A30
ZAIN
Recommended Impedance of
Analog Voltage Source
—
—
10.0
kΩ
A40
IAD
A/D Conversion PIC16F72
Current (VDD)
PIC16LF72
—
180
—
μA
—
90
—
μA
N/A
—
—
—
±5
500
μA
μA
A50
IREF
VREF input current (Note 2)
Average current
consumption when A/D
is on (Note 1).
During VAIN acquisition.
During A/D Conversion
cycle.
*
†
These parameters are characterized but not tested.
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: When A/D is off, it will not consume any current other than minor leakage current. The power-down current
spec includes any such leakage from the A/D module.
2: VREF current is from the RA3 pin or the VDD pin, whichever is selected as a reference input.
3: The A/D conversion result never decreases with an increase in the input voltage and has no missing codes.
DS39597C-page 104
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 14-16:
A/D CONVERSION TIMING
BSF ADCON0, GO
134
1 TCY
(TOSC/2)(1)
131
Q4
130
A/D CLK
132
7
A/D DATA
6
5
4
3
2
1
0
NEW_DATA
OLD_DATA
ADRES
ADIF
GO
DONE
SAMPLING STOPPED
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the
SLEEP instruction to be executed.
TABLE 14-10: A/D CONVERSION REQUIREMENTS
Param
Sym
No.
130
TAD
Characteristic
A/D Clock Period
TCNV
132
TACQ Acquisition Time
134
TGO
Q4 to A/D Clock Start
Typ† Max Units
Conditions
PIC16F72
1.6
—
—
μs
TOSC based, VREF ≥ 3.0V
PIC16LF72
2.0
—
—
μs
TOSC based,
2.0V ≤ VREF ≤ 5.5V
PIC16F72
2.0
4.0
6.0
μs
A/D RC mode
PIC16LF72
3.0
6.0
9.0
μs
A/D RC mode
9
—
9
TAD
5*
—
—
μs
The minimum time is the
amplifier settling time. This
may be used if the “new”
input voltage has not
changed by more than 1 LSb
(i.e., 20.0 mV @ 5.12V) from
the last sampled voltage (as
stated on CHOLD).
TOSC/2 —
—
If the A/D clock source is
selected as RC, a time of TCY
is added before the A/D
clock starts. This allows the
SLEEP instruction to be
executed.
Conversion Time (not including S/H time)
(Note 1)
131
Min
—
*
†
These parameters are characterized but not tested.
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: ADRES register may be read on the following TCY cycle.
© 2007 Microchip Technology Inc.
DS39597C-page 105
PIC16F72
NOTES:
DS39597C-page 106
© 2007 Microchip Technology Inc.
PIC16F72
15.0
DC AND AC CHARACTERISTICS GRAPHS AND TABLES
Note:
The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein are
not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power supply range) and therefore, outside the warranted range.
“Typical” represents the mean of the distribution at 25°C. “Maximum” or “minimum” represents (mean + 3σ) or (mean - 3σ)
respectively, where σ is a standard deviation, over the whole temperature range.
FIGURE 15-1:
TYPICAL IDD vs. FOSC OVER VDD (HS MODE)
6
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
5
5.5 V
5.0 V
4
IDD (mA)
4.5 V
4.0 V
3
2
3.5 V
3.0 V
1
2.5 V
2.0 V
0
4
6
8
10
12
14
16
18
20
F O S C (M H z )
MAXIMUM IDD vs. FOSC OVER VDD (HS MODE)
FIGURE 15-2:
8
7
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
6
5 .5 V
5 .0 V
IDD (mA)
5
4 .5 V
4
4 .0 V
3
2
3 .5 V
3 .0 V
1
2 .5 V
2 .0 V
0
4
6
8
10
12
14
16
18
20
F O S C (M H z )
© 2007 Microchip Technology Inc.
DS39597C-page 107
PIC16F72
FIGURE 15-3:
TYPICAL IDD vs. FOSC OVER VDD (XT MODE)
0.9
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
0.8
5.5V
0.7
5.0V
0.6
IDD (mA)
4.5V
0.5
4.0V
3.5V
0.4
3.0V
0.3
2.5V
2.0V
0.2
0.1
0.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
3.5
4.0
FOSC (MHz)
MAXIMUM IDD vs. FOSC OVER VDD (XT MODE)
FIGURE 15-4:
1.2
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
1.0
5.5V
5.0V
0.8
IDD (mA)
4.5V
0.6
4.0V
3.5V
3.0V
0.4
2.5V
2.0V
0.2
0.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
FOSC (MHz)
DS39597C-page 108
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 15-5:
TYPICAL IDD vs. FOSC OVER VDD (LP MODE)
55
IDD (μA)
50
45
5.5V
40
5.0V
35
4.5V
4.0V
30
3.5V
25
3.0V
20
2.5V
2.0V
15
10
30
40
50
60
70
80
90
80
90
100
FOSC (kHz)
FIGURE 15-6:
MAXIMUM IDD vs. FOSC OVER VDD (LP MODE)
100
90
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
5.5V
80
5.0V
70
IDD (μA)
4.5V
60
4.0V
50
3.5V
40
3.0V
2.5V
30
2.0V
20
30
40
50
60
70
100
FOSC (kHz)
© 2007 Microchip Technology Inc.
DS39597C-page 109
PIC16F72
FIGURE 15-7:
AVERAGE FOSC vs. VDD FOR VARIOUS VALUES OF R
(RC MODE, C = 20 pF, 25°C)
5.0
4.5
Operation above 4 MHz is not recomended
4.0
3.5
10 kΩ
Freq (MHz)
3.0
2.5
2.0
1.5
1.0
100 kΩ
0.5
0.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 15-8:
AVERAGE FOSC vs. VDD FOR VARIOUS VALUES OF R
(RC MODE, C = 100 pF, 25°C)
5.0
Operation above 4 MHz is not recomended
4.0
5.1 kΩ
Freq (MHz)
3.0
10 kΩ
2.0
1.0
100 kΩ
0.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
DS39597C-page 110
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 15-9:
AVERAGE FOSC vs. VDD FOR VARIOUS VALUES OF R
(RC MODE, C = 300 pF, 25°C)
300
250
3.3 kΩ
200
Freq (kHz)
5.1 kΩ
150
10 kΩ
100
50
100 kΩ
0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 15-10:
IPD vs. VDD (SLEEP MODE, ALL PERIPHERALS DISABLED)
100
Max 125°C
10
IPD (uA)
Max 85°C
1
Typ 25°C
0.1
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
0.01
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2007 Microchip Technology Inc.
DS39597C-page 111
PIC16F72
FIGURE 15-11:
ΔIBOR vs. VDD OVER TEMPERATURE
1,000
Max (125˚C)
Typ (25˚C)
Device in
SLEEP
Indeterminant
State
IDD (μA)
Device in
RESET
100
Note:
Device current in RESET
depends on Oscillator mode,
frequency and circuit.
Max (125˚C)
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
Typ (25˚C)
10
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
5.0
5.5
VDD (V)
FIGURE 15-12:
TYPICAL AND MAXIMUM ΔIWDT vs. VDD OVER TEMPERATURE
100
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
Max (125˚C)
ΔIWDT (μA)
10
Typ (25˚C)
1
0.1
2.0
2.5
3.0
3.5
4.0
4.5
VDD (V)
DS39597C-page 112
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 15-13:
TYPICAL, MINIMUM AND MAXIMUM WDT PERIOD vs. VDD (-40°C TO +125°C)
16F77
50
45
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
40
35
WDT Period (ms)
Max
(125°C)
30
25
Typ
(25°C)
20
Min
(-40°C)
15
10
5
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 15-14:
AVERAGE WDT PERIOD vs. VDD OVER TEMPERATURE (-40°C TO +125°C)
50
45
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
40
125°C
35
WDT Period (ms)
85°C
30
25°C
25
20
-40°C
15
10
5
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2007 Microchip Technology Inc.
DS39597C-page 113
PIC16F72
FIGURE 15-15:
TYPICAL, MINIMUM AND MAXIMUM VOH vs. IOH (VDD = 5V, -40°C TO +125°C)
5.5
5.0
4.5
4.0
Max
3.5
VOH (V)
Typ (25°C)
3.0
2.5
Min
2.0
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
1.5
1.0
0.5
0.0
0
5
10
15
20
25
IOH (-mA)
FIGURE 15-16:
TYPICAL, MINIMUM AND MAXIMUM VOH vs. IOH (VDD = 3V, -40°C TO +125°C)
3.5
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
3.0
2.5
Max
VOH (V)
2.0
Typ (25°C)
1.5
Min
1.0
0.5
0.0
0
5
10
15
20
25
IOH (-mA)
DS39597C-page 114
© 2007 Microchip Technology Inc.
PIC16F72
FIGURE 15-17:
TYPICAL, MINIMUM AND MAXIMUM VOL vs. IOL (VDD = 5V, -40°C TO +125°C)
1.0
0.9
Max (125°C)
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
0.8
0.7
Max (85°C)
VOL (V)
0.6
0.5
Typ (25°C)
0.4
0.3
Min (-40°C)
0.2
0.1
0.0
0
5
10
15
20
25
IOL (-mA)
FIGURE 15-18:
TYPICAL, MINIMUM AND MAXIMUM VOL vs. IOL (VDD = 3V, -40°C TO +125°C)
3.0
Max (125°C)
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
2.5
VOL (V)
2.0
1.5
Max (85°C)
1.0
Typ (25°C)
0.5
Min (-40°C)
0.0
0
5
10
15
20
25
IOL (-mA)
© 2007 Microchip Technology Inc.
DS39597C-page 115
PIC16F72
FIGURE 15-19:
MINIMUM AND MAXIMUM VIN vs. VDD, (TTL INPUT, -40°C TO +125°C)
1.5
1.4
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
1.3
VTH Max (-40°C)
1.2
1.1
VIN (V)
VTH Typ (25°C)
1.0
VTH Min (125°C)
0.9
0.8
0.7
0.6
0.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 15-20:
MINIMUM AND MAXIMUM VIN vs. VDD (ST INPUT, -40°C TO +125°C)
4.0
Typical: statistical mean @ 25°C
Maximum: mean + 3σ (-40°C to +125°C)
Minimum: mean – 3σ (-40°C to +125°C)
3.5
VIH Max (125°C)
3.0
VIN (V)
2.5
VIH Min (-40°C)
2.0
VIL Max (-40°C)
1.5
1.0
VIL Min (125°C)
0.5
0.0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
DS39597C-page 116
© 2007 Microchip Technology Inc.
PIC16F72
16.0
PACKAGE MARKING INFORMATION
28-Lead PDIP (Skinny DIP)
Example
PIC16F72-I/SP e3
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
28-Lead SOIC
Example
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
28-Lead SSOP
PIC16F72-I/SO e3
0710017
Example
XXXXXXXXXXXX
XXXXXXXXXXXX
YYWWNNN
28-Lead QFN
PIC16F72
-I/SS e3
0720017
Example
XXXXXXXX
XXXXXXXX
YYWWNNN
PIC16F72
-I/ML e3
0710017
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
0717017
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
© 2007 Microchip Technology Inc.
DS39597C-page 117
PIC16F72
28-Lead Skinny Plastic Dual In-Line (SP) – 300 mil Body [SPDIP]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
N
NOTE 1
E1
1
2
3
D
E
A2
A
L
c
b1
A1
b
e
eB
Units
Dimension Limits
Number of Pins
INCHES
MIN
N
NOM
MAX
28
Pitch
e
Top to Seating Plane
A
–
–
.200
Molded Package Thickness
A2
.120
.135
.150
Base to Seating Plane
A1
.015
–
–
Shoulder to Shoulder Width
E
.290
.310
.335
Molded Package Width
E1
.240
.285
.295
Overall Length
D
1.345
1.365
1.400
Tip to Seating Plane
L
.110
.130
.150
Lead Thickness
c
.008
.010
.015
b1
.040
.050
.070
b
.014
.018
.022
eB
–
–
Upper Lead Width
Lower Lead Width
Overall Row Spacing §
.100 BSC
.430
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. § Significant Characteristic.
3. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" per side.
4. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
Microchip Technology Drawing C04-070B
DS39597C-page 118
© 2007 Microchip Technology Inc.
PIC16F72
28-Lead Plastic Small Outline (SO) – Wide, 7.50 mm Body [SOIC]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
N
E
E1
NOTE 1
1 2 3
b
e
h
α
A2
A
h
c
φ
L
A1
Units
Dimension Limits
Number of Pins
β
L1
MILLMETERS
MIN
N
NOM
MAX
28
Pitch
e
Overall Height
A
–
1.27 BSC
–
Molded Package Thickness
A2
2.05
–
–
Standoff §
A1
0.10
–
0.30
Overall Width
E
Molded Package Width
E1
7.50 BSC
Overall Length
D
17.90 BSC
2.65
10.30 BSC
Chamfer (optional)
h
0.25
–
0.75
Foot Length
L
0.40
–
1.27
Footprint
L1
1.40 REF
Foot Angle Top
φ
0°
–
8°
Lead Thickness
c
0.18
–
0.33
Lead Width
b
0.31
–
0.51
Mold Draft Angle Top
α
5°
–
15°
Mold Draft Angle Bottom
β
5°
–
15°
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. § Significant Characteristic.
3. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.15 mm per side.
4. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-052B
© 2007 Microchip Technology Inc.
DS39597C-page 119
PIC16F72
28-Lead Plastic Shrink Small Outline (SS) – 5.30 mm Body [SSOP]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
N
E
E1
1 2
NOTE 1
b
e
c
A2
A
φ
A1
L
L1
Units
Dimension Limits
Number of Pins
MILLIMETERS
MIN
N
NOM
MAX
28
Pitch
e
Overall Height
A
–
0.65 BSC
–
2.00
Molded Package Thickness
A2
1.65
1.75
1.85
Standoff
A1
0.05
–
–
Overall Width
E
7.40
7.80
8.20
Molded Package Width
E1
5.00
5.30
5.60
Overall Length
D
9.90
10.20
10.50
Foot Length
L
0.55
0.75
0.95
Footprint
L1
1.25 REF
Lead Thickness
c
0.09
–
Foot Angle
φ
0°
4°
0.25
8°
Lead Width
b
0.22
–
0.38
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.20 mm per side.
3. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-073B
DS39597C-page 120
© 2007 Microchip Technology Inc.
PIC16F72
28-Lead Plastic Quad Flat, No Lead Package (ML) – 6x6 mm Body [QFN]
with 0.55 mm Contact Length
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
D2
EXPOSED
PAD
e
E
b
E2
2
2
1
1
N
K
N
NOTE 1
L
BOTTOM VIEW
TOP VIEW
A
A3
A1
Units
Dimension Limits
Number of Pins
MILLIMETERS
MIN
N
NOM
MAX
28
Pitch
e
Overall Height
A
0.80
0.65 BSC
0.90
1.00
Standoff
A1
0.00
0.02
0.05
Contact Thickness
A3
0.20 REF
Overall Width
E
Exposed Pad Width
E2
Overall Length
D
Exposed Pad Length
D2
3.65
3.70
4.20
b
0.23
0.30
0.35
Contact Length
L
0.50
0.55
0.70
Contact-to-Exposed Pad
K
0.20
–
–
Contact Width
6.00 BSC
3.65
3.70
4.20
6.00 BSC
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. Package is saw singulated.
3. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-105B
© 2007 Microchip Technology Inc.
DS39597C-page 121
PIC16F72
NOTES:
DS39597C-page 122
© 2007 Microchip Technology Inc.
PIC16F72
APPENDIX A:
REVISION HISTORY
Revision C (January 2007)
This revision includes updates to the packaging
diagrams.
Revision A (April 2002)
This is a new data sheet. However, this device is similar to the PIC16C72 device found in the PIC16C7X
Data Sheet (DS30390), the PIC16C72A Data Sheet
(DS35008) or the PIC16F872 device (DS30221).
Revision B (May 2002)
Final data sheet. Includes device characterization
data. Minor typographic revisions throughout.
APPENDIX B:
CONVERSION CONSIDERATIONS
Considerations for converting from previous versions of devices to the ones listed in this data sheet are listed in Table B-1.
TABLE B-1:
CONVERSION CONSIDERATIONS
Characteristic
PIC16C72/72A
PIC16F872
PIC16F72
Pins
28
28
28
Timers
3
3
3
Interrupts
8
10
8
Communication
Basic SSP/SSP
(SPI, I2C Slave)
MSSP
(SPI, I2C Master/Slave)
SSP
(SPI, I2C Slave)
Frequency
20 MHz
20 MHz
20 MHz
A/D
8-bit, 5 Channels
10-bit, 5 Channels
8-bit, 5 Channels
CCP
1
1
1
Program Memory
2K EPROM
2K FLASH
(1,000 E/W cycles)
2K FLASH
(1000 E/W cycles)
RAM
128 bytes
128 bytes
128 bytes
EEPROM Data
None
64 bytes
None
Other
—
In-Circuit Debugger,
Low Voltage Programming
—
© 2007 Microchip Technology Inc.
DS39597C-page 123
PIC16F72
NOTES:
DS39597C-page 124
© 2007 Microchip Technology Inc.
PIC16F72
INDEX
A
C
A/D
Capture/Compare/PWM ..................................................... 37
Associated Registers with PWM and Timer2.............. 42
Associated Registers, Capture, Compare
and Timer1............................................................. 40
Capture
CCP1IF............................................................... 38
CCPR1 ............................................................... 38
CCPR1H:CCPR1L.............................................. 38
Capture Mode............................................................. 38
CCP Mode Timer Resources...................................... 37
CCP Pin Configuration ......................................... 38, 39
CCP Prescaler............................................................ 38
CCPR1L Register ....................................................... 37
Compare Mode ........................................................... 39
PWM Mode................................................................. 41
PWM, Example Frequencies/Resolutions .................. 42
Software Interrupt ....................................................... 38
Software Interrupt Mode ............................................. 39
Special Event Trigger and A/D Conversions .............. 39
Special Event Trigger Output of CCP1 ....................... 39
Timer1 Mode Selection......................................... 38, 39
CCPR1H Register............................................................... 37
CCPxM0 bit......................................................................... 37
CCPxM1 bit......................................................................... 37
CCPxM2 bit......................................................................... 37
CCPxM3 bit......................................................................... 37
CCPxX bit ........................................................................... 37
CCPxY bit ........................................................................... 37
CKE .................................................................................... 44
CKP .................................................................................... 45
Clock Polarity Select bit, CKP............................................. 45
Code Examples
Changing Between Capture Prescalers ..................... 38
FLASH Program Read................................................ 28
Indirect Addressing..................................................... 19
Initializing PORTA....................................................... 21
Initializing PORTB ...................................................... 23
Initializing PORTC ...................................................... 25
Saving STATUS, W and PCLATH
Registers in RAM................................................... 69
Code Protection ............................................................ 59, 72
Configuration Bits ............................................................... 59
Configuration Word............................................................. 60
Conversion Considerations............................................... 123
Acquisition Requirements ........................................... 56
ADCON0 Register....................................................... 53
ADCON1 Register....................................................... 53
ADIF bit ....................................................................... 54
ADRES Register ......................................................... 53
Analog-to-Digital Converter......................................... 53
Associated Registers .................................................. 57
Configuring Analog Port Pins...................................... 56
Configuring the Interrupt ............................................. 54
Configuring the Module............................................... 54
Conversion Clock........................................................ 56
Conversions ................................................................ 56
Converter Characteristics ......................................... 104
Effects of a RESET ..................................................... 57
Internal Sampling Switch (Rss) Impedance ................ 56
Operation During SLEEP ............................................ 57
Source Impedance...................................................... 56
Use of the the CCP Trigger......................................... 57
Absolute Maximum Ratings ................................................ 87
ACK..................................................................................... 49
ADCON0
GO/DONE bit ...................................................... 54
ADRES Register ............................................................. 9, 54
Application Notes
AN546 (Using the Analog-to-Digital Converter) .......... 53
AN552 (Implementing Wake-up on
Key Strokes Using PIC16F7X) ............................... 23
AN556 (Implementing a Table Read).......................... 19
AN578 (Use of the SSP Module in the
I2C Multi-Master Environment)............................... 43
AN607 (Power-up Trouble Shooting) .......................... 64
Assembler
MPASM Assembler ..................................................... 81
B
BF ....................................................................................... 44
Block Diagrams
A/D .............................................................................. 55
Analog Input Model ..................................................... 55
Capture Mode Operation ............................................ 38
Compare Mode Operation .......................................... 39
In-Circuit Serial Programming Connections................ 72
Interrupt Logic ............................................................. 68
On-Chip Reset Circuit ................................................. 63
PIC16F72...................................................................... 5
PORTC ....................................................................... 25
PWM ........................................................................... 41
RA3:RA0 and RA5 Port Pins ...................................... 21
RA4/T0CKI Pin............................................................ 21
RB3:RB0 Port Pins ..................................................... 23
RB7:RB4 Port Pins ..................................................... 23
Recommended MCLR Circuit ..................................... 63
SSP in I2C Mode......................................................... 48
SSP in SPI Mode ........................................................ 46
Timer0/WDT Prescaler................................................ 29
Timer1 ......................................................................... 32
Timer2 ......................................................................... 35
Watchdog Timer (WDT) .............................................. 70
BOR. See Brown-out Reset
Brown-out Reset (BOR) .................................... 59, 62, 65, 66
Buffer Full Status bit, BF ..................................................... 44
© 2007 Microchip Technology Inc.
D
D/A...................................................................................... 44
Data Memory
General Purpose Register File ..................................... 7
Special Function Registers........................................... 9
Data/Address bit, D/A ......................................................... 44
DC and AC Characteristics
Graphs and Tables ................................................... 107
DC Characteristics.............................................................. 89
Development Support ......................................................... 81
Device Overview................................................................... 5
Direct Addressing ............................................................... 20
E
Electrical Characteristics .................................................... 87
Errata .................................................................................... 3
DS39597C-page 125
PIC16F72
F
FLASH Program Memory
Associated Registers .................................................. 28
Operation During Code Protect................................... 28
Reading....................................................................... 28
FSR Register................................................................... 9, 10
I
I/O Ports .............................................................................. 21
PORTA ........................................................................ 21
PORTB........................................................................ 23
PORTC........................................................................ 25
I2C
Associated Registers .................................................. 51
Master Mode ............................................................... 51
Mode Selection ........................................................... 48
Multi-Master Mode ...................................................... 51
SCL and SDA pins ...................................................... 48
Slave Mode ................................................................. 48
ICEPIC In-Circuit Emulator ................................................. 82
ID Locations ........................................................................ 72
In-Circuit Serial Programming (ICSP) ................................. 72
INDF Register ..................................................................... 10
Indirect Addressing ............................................................. 20
FSR Register .............................................................. 19
INDF Register ............................................................. 19
Instruction Format ............................................................... 73
Instruction Set ..................................................................... 73
ADDLW ....................................................................... 75
ADDWF ....................................................................... 75
ANDLW ....................................................................... 75
ANDWF ....................................................................... 75
BCF ............................................................................. 75
BSF ............................................................................. 75
BTFSC ........................................................................ 76
BTFSS ........................................................................ 76
CALL ........................................................................... 76
CLRF........................................................................... 76
CLRW.......................................................................... 76
CLRWDT..................................................................... 76
COMF ......................................................................... 77
DECF .......................................................................... 77
DECFSZ...................................................................... 77
GOTO.......................................................................... 77
INCF............................................................................ 77
INCFSZ ....................................................................... 77
IORLW......................................................................... 78
IORWF ........................................................................ 78
MOVF.......................................................................... 78
MOVLW....................................................................... 78
MOVWF ...................................................................... 78
NOP ............................................................................ 78
RETFIE ....................................................................... 79
RETLW........................................................................ 79
RETURN ..................................................................... 79
RLF ............................................................................. 79
RRF............................................................................. 79
SLEEP ........................................................................ 79
SUBLW........................................................................ 80
SUBWF ....................................................................... 80
Summary Table ........................................................... 74
SWAPF ....................................................................... 80
XORLW ....................................................................... 80
XORWF....................................................................... 80
DS39597C-page 126
INT Interrupt (RB0/INT). See Interrupt Sources
INTCON Register
GIE bit......................................................................... 14
INTE bit....................................................................... 14
INTF bit ....................................................................... 14
RBIF bit....................................................................... 14
TMR0IE bit.................................................................. 14
Internal Sampling Switch (Rss) Impedance........................ 56
Interrupt Sources .......................................................... 59, 68
RB0/INT Pin, External................................................. 69
TMR0 Overflow........................................................... 69
Interrupts
RB7:RB4 Port Change................................................ 23
Synchronous Serial Port Interrupt............................... 16
Interrupts, Context Saving During....................................... 69
Interrupts, Enable Bits
Global Interrupt Enable (GIE bit) .......................... 14, 68
Interrupt-on-Change (RB7:RB4)
Enable (RBIE bit) ................................................... 69
RB0/INT Enable (INTE bit) ......................................... 14
TMR0 Overflow Enable (TMR0IE bit) ......................... 14
Interrupts, Flag bits
Interrupt-on-Change (RB7:RB4) Flag
(RBIF bit) ............................................................... 14
Interrupt-on-Change (RB7:RB4) Flag
(RBIF bit) ......................................................... 14, 69
RB0/INT Flag (INTF bit).............................................. 14
TMR0 Overflow Flag (TMR0IF bit).............................. 69
K
KEELOQ Evaluation and Programming Tools ...................... 84
L
Loading of PC ..................................................................... 18
M
Master Clear (MCLR)
MCLR Reset, Normal Operation..................... 62, 65, 66
MCLR Reset, SLEEP...................................... 62, 65, 66
Operation and ESD Protection ................................... 63
Memory
Data Memory ................................................................ 7
Program Memory .......................................................... 7
MPLAB C17 and MPLAB C18 C Compilers ....................... 81
MPLAB ICD In-Circuit Debugger ........................................ 83
MPLAB ICE High Performance Universal
In-Circuit Emulator with MPLAB IDE ............................ 82
MPLAB Integrated Development
Environment Software .................................................. 81
MPLINK Object Linker/MPLIB Object Librarian .................. 82
O
On-Line Support ............................................................... 131
OPCODE Field Descriptions............................................... 73
OPTION_REG Register
INTEDG bit ................................................................. 13
PS2:PS0 bits............................................................... 13
PSA bit........................................................................ 13
RBPU bit ..................................................................... 13
T0CS bit...................................................................... 13
T0SE bit ...................................................................... 13
© 2007 Microchip Technology Inc.
PIC16F72
Oscillator Configuration................................................. 59, 61
Crystal Oscillator/Ceramic Resonators ....................... 61
HS ......................................................................... 61, 65
LP.......................................................................... 61, 65
RC................................................................... 61, 62, 65
XT ......................................................................... 61, 65
Oscillator, WDT ................................................................... 70
P
P.......................................................................................... 44
Package Marking Information ........................................... 117
PCFG0 bit ........................................................................... 54
PCFG1 bit ........................................................................... 54
PCFG2 bit ........................................................................... 54
PCL Register............................................................. 9, 10, 18
PCLATH Register ..................................................... 9, 10, 18
PCON Register ................................................................... 64
POR bit ....................................................................... 17
PICDEM 1 Low Cost PIC
Demonstration Board.................................................... 83
PICDEM 17 Demonstration Board ...................................... 84
PICDEM 2 Low Cost PIC16CXX
Demonstration Board.................................................... 83
PICDEM 3 Low Cost PIC16CXXX
Demonstration Board.................................................... 84
PICSTART Plus Entry Level
Development Programmer ........................................... 83
Pin Functions
MCLR/VPP..................................................................... 6
OSC1/CLKI ................................................................... 6
OSC2/CLKO ................................................................. 6
RA0/AN0 ....................................................................... 6
RA1/AN1 ....................................................................... 6
RA2/AN2 ....................................................................... 6
RA3/AN3/VREF .............................................................. 6
RA4/T0CKI.................................................................... 6
RA5/AN4/SS ................................................................. 6
RB0/INT ........................................................................ 6
RB1 ............................................................................... 6
RB2 ............................................................................... 6
RB3 ............................................................................... 6
RB4 ............................................................................... 6
RB5 ............................................................................... 6
RB6/PGC ...................................................................... 6
RB7/PGD ...................................................................... 6
RC0/T1OSO/T1CKI ...................................................... 6
RC1/T1OSI ................................................................... 6
RC2/CCP1 .................................................................... 6
RC3/SCK/SCL .............................................................. 6
RC4/SDI/SDA ............................................................... 6
RC5/SDO ...................................................................... 6
RC6............................................................................... 6
RC7............................................................................... 6
VDD ............................................................................... 6
VSS ................................................................................ 6
Pinout Descriptions
PIC16F72...................................................................... 6
POP .................................................................................... 19
POR. See Power-on Reset
PORTA
Associated Registers .................................................. 22
Functions .................................................................... 22
© 2007 Microchip Technology Inc.
PORTA Register ................................................................... 9
PORTB
Associated Registers.................................................. 24
Functions .................................................................... 24
Pull-up Enable (RBPU bit) .......................................... 13
RB0/INT Edge Select (INTEDG bit)............................ 13
RB0/INT Pin, External ................................................ 69
RB7:RB4 Interrupt-on-Change Flag (RBIF bit)........... 14
RB7:RB4 Interrupt-on-Change ................................... 69
RB7:RB4 Interrupt-on-Change Enable
(RBIE bit) ............................................................... 69
RB7:RB4 Interrupt-on-Change Flag
(RBIF bit) ......................................................... 14, 69
PORTB Register ................................................................... 9
PORTC
Associated Registers.................................................. 26
Functions .................................................................... 26
PORTC Register................................................................... 9
Postscaler, WDT
Assignment (PSA Bit) ................................................. 13
Rate Select (PS2:PS0 bits) ........................................ 13
Power-down Mode. See SLEEP
Power-on Reset (POR)............................... 59, 62, 64, 65, 66
Brown-out Reset (BOR).............................................. 64
Oscillator Start-up Timer (OST) ............................ 59, 64
POR Status (POR bit)................................................. 17
Power Control/Status Register (PCON)...................... 64
Power-down (PD bit) .................................................. 62
Power-up Timer (PWRT) ...................................... 59, 64
Time-out (TO bit) .................................................. 12, 62
Time-out Sequence .................................................... 64
PR2 Register ...................................................................... 35
Prescaler, Timer0
Assignment (PSA bit) ................................................. 13
Rate Select (PS2:PS0 bits) ........................................ 13
PRO MATE II Universal Device Programmer ..................... 83
Product Identification System ........................................... 133
Program Counter
RESET Conditions...................................................... 65
Program Memory
Paging ........................................................................ 19
Program Memory Map and Stack ......................................... 7
Program Verification ........................................................... 72
PUSH.................................................................................. 19
R
R/W..................................................................................... 44
R/W bit ................................................................................ 49
RBIF bit............................................................................... 23
Read/Write bit Information, R/W ......................................... 44
Reader Response............................................................. 132
Reading Program Memory.................................................. 27
PMADR....................................................................... 27
PMCON1 Register...................................................... 27
Receive Overflow Indicator bit, SSPOV.............................. 45
Register File Map.................................................................. 8
DS39597C-page 127
PIC16F72
Registers ............................................................................. 36
ADCON0 (A/D Control 0) ............................................ 53
ADCON1 (A/D Control 1) ............................................ 54
CCPCON1 (Capture/Compare/PWM Control 1) ......... 37
Initialization Conditions (table) .................................... 66
INTCON (Interrupt Control) ......................................... 14
OPTION ...................................................................... 13
PCON (Power Control) ............................................... 17
PIE1 (Peripheral Interrupt Enable 1) ........................... 15
PIR1 (Peripheral Interrupt Flag 1) ............................... 16
PMCON1 (Program Memory Control 1) ...................... 27
SSPCON (Sync Serial Port Control) ........................... 45
SSPSTAT (Synchronous Serial Port Status) ............... 44
STATUS ...................................................................... 12
Summary....................................................................... 9
T1CON (Timer1 Control) ............................................. 31
RESET .......................................................................... 59, 62
Brown-out Reset (BOR). See Brown-out Reset (BOR)
MCLR RESET. See MCLR
Power-on Reset (POR). See Power-on Reset (POR)
RESET Conditions for All Registers............................ 66
RESET Conditions for PCON Register ....................... 65
RESET Conditions for Program Counter .................... 65
RESET Conditions for STATUS Register .................... 65
WDT Reset. See Watchdog Timer (WDT)
Revision History ................................................................ 123
RP0, RP1 bit ......................................................................... 7
S
S.......................................................................................... 44
Sales and Support............................................................. 133
Slave Mode
SCL ............................................................................. 48
SDA............................................................................. 48
SLEEP..................................................................... 59, 62, 71
SMP .................................................................................... 44
Software Simulator (MPLAB SIM)....................................... 82
Special Event Trigger.......................................................... 57
Special Features of the CPU............................................... 59
Special Function Registers
PMADRH .................................................................... 27
PMADRL ..................................................................... 27
PMCON1..................................................................... 27
PMDATH ..................................................................... 27
PMDATL...................................................................... 27
SPI
Associated Registers .................................................. 46
SPI Clock Edge Select bit, CKE.......................................... 44
SPI Data Input Sample Phase Select bit, SMP................... 44
SPI Mode
Serial Clock ................................................................. 43
Serial Data In .............................................................. 43
Serial Data Out............................................................ 43
Slave Select ................................................................ 43
SSP
ACK............................................................................. 48
Addressing .................................................................. 48
BF bit........................................................................... 48
I2C Mode Operation .................................................... 48
R/W bit ........................................................................ 49
Reception .................................................................... 49
SCL Clock Input .......................................................... 48
SSPOV bit ................................................................... 48
Transmission............................................................... 49
DS39597C-page 128
SSPADD Register............................................................... 10
SSPEN................................................................................ 45
SSPIF ................................................................................. 16
SSPM3:SSPM0 .................................................................. 45
SSPOV ............................................................................... 45
SSPSTAT Register ............................................................. 10
Stack................................................................................... 19
Overflows.................................................................... 19
Underflow ................................................................... 19
START bit, S....................................................................... 44
STATUS Register
DC bit.......................................................................... 12
IRP bit ......................................................................... 12
PD bit .......................................................................... 62
TO bit .................................................................... 12, 62
STOP bit, P......................................................................... 44
Synchronous Serial Port (SSP) .......................................... 43
Overview..................................................................... 43
SPI Mode .................................................................... 43
Synchronous Serial Port Enable bit, SSPEN...................... 45
Synchronous Serial Port Interrupt....................................... 16
Synchronous Serial Port Mode Select bits,
SSPM3:SSPM0 ............................................................ 45
T
T2CKPS0 bit ....................................................................... 36
T2CKPS1 bit ....................................................................... 36
T2CON (Timer2 Control) .................................................... 36
TAD...................................................................................... 56
Timer0................................................................................. 29
Clock Source Edge Select (T0SE bit)......................... 13
Clock Source Select (T0CS bit) .................................. 13
External Clock............................................................. 30
Interrupt ...................................................................... 29
Operation .................................................................... 29
Overflow Enable (TMR0IE bit) .................................... 14
Overflow Flag (TMR0IF bit) ........................................ 69
Overflow Interrupt ....................................................... 69
Prescaler .................................................................... 30
T0CKI ......................................................................... 30
Timer1
Associated Registers .................................................. 34
Asynchronous Counter Mode ..................................... 33
Capacitor Selection..................................................... 33
Counter Operation ...................................................... 32
Interrupt ...................................................................... 33
Operation in Timer Mode ............................................ 32
Oscillator..................................................................... 33
Prescaler .................................................................... 34
Resetting TMR1H, TMR1L Register Pair.................... 34
Resetting Using a CCP Trigger Output....................... 33
Synchronized Counter Mode ...................................... 32
Timer2................................................................................. 35
Interrupt ...................................................................... 35
Operation .................................................................... 35
Output ......................................................................... 35
Prescaler, Postscaler .................................................. 35
© 2007 Microchip Technology Inc.
PIC16F72
Timing Diagrams
A/D Conversion......................................................... 105
Brown-out Reset ......................................................... 96
Capture/Compare/PWM (CCP1)................................. 98
CLKO and I/O ............................................................. 95
External Clock............................................................. 94
I2C Bus Data ............................................................. 102
I2C Bus START/STOP bits........................................ 101
I2C Reception (7-bit Address) ..................................... 50
I2C Transmission (7-bit Address) ................................ 50
RESET, Watchdog Timer, Oscillator Start-up Timer
and Power-up Timer............................................... 96
Slow Rise Time (MCLR Tied to VDD Through
RC Network)........................................................... 68
SPI Master Mode ........................................................ 47
SPI Master Mode (CKE = 0, SMP = 0) ....................... 99
SPI Master Mode (CKE = 1, SMP = 1) ....................... 99
SPI Slave Mode (CKE = 0) ................................. 47, 100
SPI Slave Mode (CKE = 1) ................................. 47, 100
Time-out Sequence on Power-up (MCLR Tied to
VDD Through Pull-up Resistor)............................... 67
Time-out Sequence on Power-up (MCLR Tied to
VDD Through RC Network): Case 1 ....................... 67
Time-out Sequence on Power-up (MCLR Tied to
VDD Through RC Network): Case 2 ....................... 67
Timer0 and Timer1 External Clock.............................. 97
Wake-up from SLEEP through Interrupt ..................... 72
Timing Parameter Symbology............................................. 93
TMR1H Register ................................................................... 9
TMR1L Register .................................................................... 9
TMR2 Register ...................................................................... 9
TMR2ON bit ........................................................................ 36
TOUTPS0 bit....................................................................... 36
TOUTPS1 bit....................................................................... 36
TOUTPS2 bit....................................................................... 36
TOUTPS3 bit....................................................................... 36
TRISA Register ............................................................. 10, 21
TRISB Register ............................................................. 10, 23
TRISC Register ............................................................. 10, 25
© 2007 Microchip Technology Inc.
U
UA....................................................................................... 44
Update Address bit, UA ...................................................... 44
W
Wake-up from SLEEP................................................... 59, 71
Interrupts .............................................................. 65, 66
MCLR Reset ............................................................... 66
WDT Reset ................................................................. 66
Watchdog Timer (WDT)................................................ 59, 70
Associated Registers.................................................. 70
Enable (WDTEN bit) ................................................... 70
Postscaler. See Postscaler, WDT
Programming Considerations ..................................... 70
RC Oscillator .............................................................. 70
Time-out Period .......................................................... 70
WDT Reset, Normal Operation....................... 62, 65, 66
WDT Reset, SLEEP ....................................... 62, 65, 66
WCOL ................................................................................. 45
Write Collision Detect bit, WCOL........................................ 45
WWW, On-Line Support ....................................................... 3
DS39597C-page 129
PIC16F72
NOTES:
DS39597C-page 130
© 2007 Microchip Technology Inc.
DSTEMP
THE MICROCHIP WEB SITE
CUSTOMER SUPPORT
Microchip provides online support via our WWW site at
www.microchip.com. This web site is used as a means
to make files and information easily available to
customers. Accessible by using your favorite Internet
browser, the web site contains the following
information:
Users of Microchip products can receive assistance
through several channels:
• Product Support – Data sheets and errata,
application notes and sample programs, design
resources, user’s guides and hardware support
documents, latest software releases and archived
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• General Technical Support – Frequently Asked
Questions (FAQ), technical support requests,
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• Business of Microchip – Product selector and
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•
•
•
•
•
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Customers
should
contact
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representative or field application engineer (FAE) for
support. Local sales offices are also available to help
customers. A listing of sales offices and locations is
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Technical support is available through the web site
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CUSTOMER CHANGE NOTIFICATION
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© 2005 Microchip Technology Inc.
Advance Information
DS00000A-page 131
DSTEMP
READER RESPONSE
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Literature Number: DS00000A
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DS00000A-page 132
Advance Information
© 2005 Microchip Technology Inc.
PIC16F72
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
Device
*
X
Temperature
Range
/XX
XXX
Package
Pattern
Device
PIC16F72: Standard VDD range
PIC16F72T: (Tape and Reel)
PIC16LF72: Extended VDD range
Temperature Range
I
Package
SO
SS
ML
P
Pattern
QTP, SQTP, ROM Code (factory specified) or
Special Requirements. Blank for OTP and
Windowed devices.
=
=
Examples:
a)
PIC16F72-04I/SO = Industrial Temp.,
SOIC package, normal VDD limits
b)
PIC16LF72-20I/SS = Industrial Temp.,
SSOP package, extended VDD limits
c)
PIC16F72-20I/ML = Industrial Temp.,
QFN package, normal VDD limits
0°C to +70°C
-40°C to +85°C
=
=
=
=
SOIC
SSOP
QFN
PDIP
JW Devices are UV erasable and can be programmed to any device configuration. JW Devices meet the electrical requirement of
each oscillator type.
© 2007 Microchip Technology Inc.
DS39597C-page 133
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://support.microchip.com
Web Address:
www.microchip.com
Asia Pacific Office
Suites 3707-14, 37th Floor
Tower 6, The Gateway
Habour City, Kowloon
Hong Kong
Tel: 852-2401-1200
Fax: 852-2401-3431
India - Bangalore
Tel: 91-80-4182-8400
Fax: 91-80-4182-8422
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
India - Pune
Tel: 91-20-2566-1512
Fax: 91-20-2566-1513
France - Paris
Tel: 33-1-69-53-63-20
Fax: 33-1-69-30-90-79
Japan - Yokohama
Tel: 81-45-471- 6166
Fax: 81-45-471-6122
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
Boston
Westborough, MA
Tel: 774-760-0087
Fax: 774-760-0088
Chicago
Itasca, IL
Tel: 630-285-0071
Fax: 630-285-0075
Dallas
Addison, TX
Tel: 972-818-7423
Fax: 972-818-2924
Detroit
Farmington Hills, MI
Tel: 248-538-2250
Fax: 248-538-2260
Kokomo
Kokomo, IN
Tel: 765-864-8360
Fax: 765-864-8387
Los Angeles
Mission Viejo, CA
Tel: 949-462-9523
Fax: 949-462-9608
Santa Clara
Santa Clara, CA
Tel: 408-961-6444
Fax: 408-961-6445
Toronto
Mississauga, Ontario,
Canada
Tel: 905-673-0699
Fax: 905-673-6509
Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
China - Beijing
Tel: 86-10-8528-2100
Fax: 86-10-8528-2104
China - Chengdu
Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
Korea - Gumi
Tel: 82-54-473-4301
Fax: 82-54-473-4302
China - Fuzhou
Tel: 86-591-8750-3506
Fax: 86-591-8750-3521
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Malaysia - Penang
Tel: 60-4-646-8870
Fax: 60-4-646-5086
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Taiwan - Hsin Chu
Tel: 886-3-572-9526
Fax: 886-3-572-6459
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
China - Shunde
Tel: 86-757-2839-5507
Fax: 86-757-2839-5571
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
UK - Wokingham
Tel: 44-118-921-5869
Fax: 44-118-921-5820
China - Xian
Tel: 86-29-8833-7250
Fax: 86-29-8833-7256
12/08/06
DS39597C-page 134
© 2007 Microchip Technology Inc.
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