Microchip Technology PIC16C62B/72A User Manual

PIC16C72A
MCLR/VPP
RA0/AN0 RA1/AN1 RA2/AN2
RA3/AN3/V
REF
RA4/T0CKI
RA5/SS/AN4
V
SS
OSC1/CLKIN
OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0/INT V
DD
VSS RC7 RC6 RC5/SDO RC4/SDI/SDA
• 1 2 3 4 5 6 7 8 9 10 11 12 13 14
28 27 26 25 24 23 22 21 20 19 18 17 16 15
SDIP, SOIC, SSOP, Windowed CERDIP
PIC16C62B/72A
28-Pin 8-Bit CMOS Microcontrollers
Microcontroller Core Features:
• High-performance RISC CPU
• 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
• Interrupt capability
• Eight level deep hardware stack
• Direct, indirect, and relative addressing modes
• 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
• Brown-out detection circuitry for Brown-out Reset (BOR)
• Programmable code-protection
• Power saving SLEEP mode
• Selectable oscillator options
• Low-power, high-speed CMOS EPROM technology
• Fully static design
• In-Circuit Serial Programming(ICSP)
• Wide operating voltage range: 2.5V to 5.5V
• High Sink/Source Current 25/25 mA
• Commercial, Industrial and Extended temperature ranges
• Low-power consumption:
- < 2 mA @ 5V, 4 MHz
- 22.5 A typical @ 3V, 32 kHz
-< 1 A typical standby current
Pin Diagram
Peripheral Features:
• 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 module
• Capture is 16-bit, max. resolution is 12.5 ns, Compare is 16-bit, max. resolution is 200 ns, PWM maximum resolution is 10-bit
• 8-bit multi-channel Analog-to-Digital converter
• Synchronous Serial Port (SSP) with Enhanced SPI and I
2C
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 1
PIC16C62B/72A
PIC16C62B
MCLR/VPP
RA0 RA1 RA2 RA3
RA4/T0CKI
RA5/SS
V
SS
OSC1/CLKIN
OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI
RC2/CCP1
RC3/SCK/SCL
RB7 RB6 RB5 RB4 RB3 RB2 RB1
RB0/INT V
DD
VSS RC7 RC6 RC5/SDO RC4/SDI/SDA
• 1 2 3 4 5 6 7
8 9 10 11 12 13 14
28 27 26 25 24 23 22
21 20 19 18 17 16 15
SDIP, SOIC, SSOP, Windowed CERDIP
Pin Diagrams
Key Features
PIC® Mid-Range Reference Manual (DS33023)
PIC16C62B PIC16C72A
Operating Frequency DC - 20 MHz DC - 20 MHz
Resets (and Delays) POR, BOR (PWRT, OST) POR, BOR (PWRT, OST)
Program Memory (14-bit words) 2K 2K
Data Memory (bytes) 128 128
Interrupts 7 8
I/O Ports Ports A,B,C Ports A,B,C
Timers 3 3
Capture/Compare/PWM modules 1 1
Serial Communications SSP SSP
8-bit Analog-to-Digital Module 5 input channels
DS35008C-page 2 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
Table of Contents
1.0 Device Overview .................................................................................................................................................... 5
2.0 Memory Organization............................................................................................................................................. 7
3.0 I/O Ports ............................................................................................................................................................... 19
4.0 Timer0 Module ..................................................................................................................................................... 25
5.0 Timer1 Module ..................................................................................................................................................... 27
6.0 Timer2 Module ..................................................................................................................................................... 31
7.0 Capture/Compare/PWM (CCP) Module ............................................................................................................... 33
8.0 Synchronous Serial Port (SSP) Module ............................................................................................................... 39
9.0 Analog-to-Digital Converter (A/D) Module............................................................................................................ 49
10.0 Special Features of the CPU................................................................................................................................ 55
11.0 Instruction Set Summary ...................................................................................................................................... 67
12.0 Development Support........................................................................................................................................... 75
13.0 Electrical Characteristics...................................................................................................................................... 81
14.0 DC and AC Characteristics Graphs and Tables................................................................................................. 103
15.0 Packaging Information........................................................................................................................................ 105
Appendix A: Revision History ................................................................................................................................... 111
Appendix B: Conversion Considerations .................................................................................................................. 111
Appendix C: Migration from Base-line to Mid-Range Devices .................................................................................. 112
Index ...........................................................................................................................................................................113
On-Line Support.......................................................................................................................................................... 117
Reader Response....................................................................................................................................................... 118
PIC16C62B/72A Product Identification System .......................................................................................................... 119
To Our Valued Customers
Most Current Data Sheet
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http://www.microchip.com
You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page. The last character of the literature number is the version number. e.g., DS30000A is version A of document DS30000.
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Errata
An errata sheet may exist for current devices, describing minor operational differences (from the data sheet) and recommended workarounds. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revi­sion of silicon and revision of document to which it applies.
To determine if an errata sheet exists for a particular device, please check with one of the following:
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When contacting a sales office or the literature center, please specify which device, revision of silicon and data sheet (include liter­ature number) you are using.
Corrections to this Data Sheet
We constantly strive to improve the quality of all our products and documentation. We have spent a great deal of time to ensure that this document is correct. However, we realize that we may have missed a few things. If you find any information that is missing or appears in error, please:
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We appreciate your assistance in making this a better document.
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 3
PIC16C62B/72A
NOTES:
DS35008C-page 4 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
EPROM
Program Memory
13
Data Bus
8
14
Program
Bus
Instruction reg
Program Counter
8 Level Stack
(13-bit)
RAM
File
Registers
Direct Addr
7
RAM Addr
(1)
9
Addr MUX
Indirect
Addr
FSR reg
STATUS reg
MUX
ALU
W reg
Power-up
Timer
Oscillator
Start-up Timer
Power-on
Reset
Watchdog
Timer
Instruction Decode &
Control
Timing
Generation
OSC1/CLKIN OSC2/CLKOUT
MCLR
VDD, VSS
PORTA
PORTB
PORTC
RB0/INT
RB7:RB1
RC0/T1OSO/T1CKI RC1/T1OSI RC2/CCP1 RC3/SCK/SCL RC4/SDI/SDA RC5/SDO RC6 RC7
8
8
Brown-out
Reset
Note 1: Higher order bits are from the STATUS register.
2: The A/D module is not available on the PIC16C62B.
CCP1
Synchronous
A/D
(2)
Timer0 Timer1 Timer2
Serial Port
RA4/T0CKI RA5/SS
/AN4
(2)
RA3/AN3/VREF
(2)
RA2/AN2
(2)
RA1/AN1
(2)
RA0/AN0
(2)
8
3
2K x 14
128 x 8
1.0 DEVICE OVERVIEW
This document contains device-specific information. Additional information may be found in the PIC Mid-Range Reference Manual, (DS33023), which may be obtained from your local Microchip Sales Represen­tative or downloaded from the Microchip website. The Reference Manual should be considered a comple­mentary document to this data sheet, and is highly rec-
FIGURE 1-1: PIC16C62B/PIC16C72A BLOCK DIAGRAM
®
MCU
ommended reading for a better understanding of the device architecture and operation of the peripheral modules.
There are two devices (PIC16C62B, PIC16C72A) cov­ered by this datasheet. The PIC16C62B does not have the A/D module implemented.
Figure 1-1 is the block diagram for both devices. The pinouts are listed in Table 1-1.
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 5
PIC16C62B/72A
TABLE 1-1 PIC16C62B/PIC16C72A PINOUT DESCRIPTION
Pin Name
DIP
Pin#
OSC1/CLKIN 9 9 I
SOIC
Pin#
I/O/P Typ e
Buffer
Typ e
ST/CMOS
Description
(3)
Oscillator crystal input/external clock source input.
OSC2/CLKOUT 10 10 O Oscillator crystal output. Connects to crystal or resonator in
crystal oscillator mode. In RC mode, the OSC2 pin outputs CLKOUT which has 1/4 the frequency of OSC1, and denotes the instruction cycle rate.
MCLR
/VPP
1 1 I/P ST Master clear (reset) input or programming voltage input. This
pin is an active low reset to the device.
PORTA is a bi-directional I/O port.
RA0/AN0
RA1/AN1
RA2/AN2
RA3/AN3/V
(4)
(4)
(4)
(4)
REF
2 2 I/O TTL RA0 can also be analog input 0
3 3 I/O TTL RA1 can also be analog input 1
4 4 I/O TTL RA2 can also be analog input 2
5 5 I/O TTL RA3 can also be analog input 3 or analog reference voltage
RA4/T0CKI 6 6 I/O ST RA4 can also be the clock input to the Timer0 module.
Output is open drain type.
RA5/SS/
AN4
(4)
7 7 I/O TTL RA5 can also be analog input 4 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 21 I/O TTL/ST
(1)
RB0 can also be the external interrupt pin.
RB1 22 22 I/O TTL
RB2 23 23 I/O TTL
RB3 24 24 I/O TTL
RB4 25 25 I/O TTL Interrupt on change pin.
RB5 26 26 I/O TTL Interrupt on change pin.
RB6 27 27 I/O TTL/ST
RB7 28 28 I/O TTL/ST
(2)
(2)
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 11 I/O ST RC0 can also be the Timer1 oscillator output or Timer1
clock input.
RC1/T1OSI 12 12 I/O ST RC1 can also be the Timer1 oscillator input.
RC2/CCP1 13 13 I/O ST RC2 can also be the Capture1 input/Compare1 output/
PWM1 output.
RC3/SCK/SCL 14 14 I/O ST RC3 can also be the synchronous serial clock input/output
for both SPI and I
RC4/SDI/SDA 15 15 I/O ST RC4 can also be the SPI Data In (SPI mode) or
data I/O (I
2
C mode).
2
C modes.
RC5/SDO 16 16 I/O ST RC5 can also be the SPI Data Out (SPI mode).
RC6 17 17 I/O ST
RC7 18 18 I/O ST
SS 8, 19 8, 19 P Ground reference for logic and I/O pins.
V
DD 20 20 P Positive supply for logic and I/O pins.
V
Legend: I = input O = output I/O = input/output P = power or program
— = 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. 4: The A/D module is not available on the PIC16C62B.
DS35008C-page 6 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
PC<12:0>
13
0000h
0004h 0005h
07FFh
0800h
1FFFh
Stack Level 1
Stack Level 8
Reset Vector
Interrupt Vector
On-chip Program
Memory
CALL, RETURN RETFIE, RETLW
User Memory
Space
2.0 MEMORY ORGANIZATION
There are two memory blocks in each of these micro­controllers. Each block (Program Memory and Data Memory) has its own bus, so that concurrent access can occur.
Additional information on device memory may be found in the PICmicro Mid-Range Reference Manual, (DS33023).
2.1 Program Memory Organization
The PIC16C62B/72A devices have a 13-bit program counter capable of addressing an 8K x 14 program memory space. Each device has 2K x 14 words of pro­gram memory. Accessing a location above 07FFh 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
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 7
PIC16C62B/72A
Unimplemented data memory locations,
read as '0'.
Note 1: Not a physical register.
2: These registers are not implemented on the
PIC16C62B, read as '0'.
File
Address
File
Address
00h INDF
(1)
INDF
(1)
80h
01h TMR0 OPTION_REG 81h
02h PCL PCL 82h
0 3 h S TATU S S TAT U S 8 3 h
04h FSR FSR 84h
05h PORTA TRISA 85h
06h PORTB TRISB 86h
07h PORTC TRISC 87h
08h
88h
09h
89h
0Ah PCLATH PCLATH 8Ah
0Bh INTCON INTCON 8Bh
0Ch PIR1 PIE1 8Ch
0Dh
8Dh
0Eh TMR1L PCON 8Eh
0Fh TMR1H
8Fh
10h T1CON
90h
11h TMR2
91h
12h T2CON PR2 92h
13h SSPBUF SSPADD 93h
14h SSPCON SSPSTAT 94h
15h CCPR1L
95h
16h CCPR1H
96h
17h CCP1CON
97h
18h
98h
19h
99h
1Ah
9Ah
1Bh
9Bh
1Ch
9Ch
1Dh
9Dh
1Eh ADRES
(2)
9Eh
1Fh ADCON0
(2)
ADCON1
(2)
9Fh
20h
General
Purpose
Registers
General Purpose
Registers
A0h
BFh
C0h
7Fh
FFh
Bank 0 Bank 1
2.2 Data Memory Organization
The data memory is partitioned into multiple banks which contain the General Purpose Registers and the Special Function Registers. Bits RP1 and RP0 are the bank select bits.
(1)
RP1
= 00 Bank0 = 01 Bank1 = 10 Bank2 (not implemented) = 11 Bank3 (not implemented)
Note 1: Maintain this bit clear to ensure upward compati-
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 Special Function Registers. Some “high use” Special Function Registers from one bank may be mirrored in another bank for code reduction and quicker access.
2.2.1 GENERAL PURPOSE REGISTER FILE
The register file can be accessed either directly, or indi­rectly through the File Select Register FSR (Section 2.5).
DS35008C-page 8 Preliminary 1998-2013 Microchip Technology Inc.
RP0 (STATUS<6:5>)
bility with future products.
FIGURE 2-2: REGISTER FILE MAP
PIC16C62B/72A
2.2.2 SPECIAL FUNCTION REGISTERS
The Special Function Registers can be classified into two sets; core (CPU) and peripheral. Those registers
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.
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.
TABLE 2-1 SPECIAL FUNCTION REGISTER SUMMARY
Addr Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Val ue on:
POR,
BOR
Bank 0
00h INDF
01h TMR0 Timer0 module’s register xxxx xxxx uuuu uuuu
02h PCL
03h STATUS
04h FSR
05h PORTA
06h PORTB
07h PORTC
08h-09h Unimplemented
0Ah PCLATH
0Bh INTCON
0Ch PIR1
0Dh Unimplemented
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
11h TMR2 Timer2 module’s register 0000 0000 0000 0000
12h T2CON
13h SSPBUF Synchronous Serial Port Receive Buffer/Transmit Register xxxx xxxx uuuu uuuu
14h SSPCON WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000 0000 0000
15h CCPR1L Capture/Compare/PWM Register1 (LSB) xxxx xxxx uuuu uuuu
16h CCPR1H Capture/Compare/PWM Register1 (MSB) xxxx xxxx uuuu uuuu
17h CCP1CON
18h-1Dh Unimplemented
1Eh ADRES
1Fh ADCON0
Legend: x = unknown, u = unchanged, q = value depends on condition, - = unimplemented, read as '0',
Note 1: These registers can be addressed from either bank.
2: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for PC<12:8> whose contents
3: A/D not implemented on the PIC16C62B, maintain as ’0’. 4: Other (non power-up) resets include: external reset through MCLR 5: The IRP and RP1 bits are reserved. Always maintain these bits clear. 6: On any device reset, these pins are configured as inputs. 7: This is the value that will be in the port output latch.
(1)
(1)
(1)
Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000 0000 0000
Program Counter's (PC) Least Significant Byte 0000 0000 0000 0000
(1)
(6,7)
(6,7)
(6,7)
(1,2)
(1)
(3)
(3)
(5)
IRP
Indirect data memory address pointer xxxx xxxx uuuu uuuu
PORTA Data Latch when written: PORTA pins when read --0x 0000 --0u 0000
PORTB Data Latch when written: PORTB pins when read xxxx xxxx uuuu uuuu
PORTC Data Latch when written: PORTC pins when read xxxx xxxx uuuu uuuu
Write Buffer for the upper 5 bits of the Program Counter ---0 0000 ---0 0000
GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u
—ADIF
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
CCP1X CCP1Y CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
A/D Result Register xxxx xxxx uuuu uuuu
ADCS1 ADCS0 CHS2 CHS1 CHS0 GO/DONE —ADON0000 00-0 0000 00-0
RP1
(5)
RP0 TO PD ZDCC0001 1xxx 000q quuu
(3)
SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000
Shaded locations are unimplemented, read as '0'.
are transferred to the upper byte of the program counter.
and the Watchdog Timer Reset.
Value on all
other resets
(4)
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 9
PIC16C62B/72A
TABLE 2-1 SPECIAL FUNCTION REGISTER SUMMARY (Cont.’d)
Addr Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Bank 1
80h INDF
81h OPTION_REG RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111
82h PCL
83h STATUS
84h FSR
85h TRISA
86h TRISB PORTB Data Direction Register 1111 1111 1111 1111
87h TRISC PORTC Data Direction Register 1111 1111 1111 1111
88h-89h Unimplemented
8Ah PCLATH
8Bh INTCON
8Ch PIE1
8Dh Unimplemented
8Eh PCON —PORBOR ---- --qq ---- --uu
8Fh-91h Unimplemented
92h PR2 Timer2 Period Register 1111 1111 1111 1111
93h SSPADD Synchronous Serial Port (I
94h SSPSTAT SMP CKE D/A
95h-9Eh Unimplemented
9Fh ADCON1
(1)
(1)
(1)
Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000 0000 0000
Program Counter's (PC) Least Significant Byte 0000 0000 0000 0000
(1)
(1,2)
(1)
(3)
(5)
IRP
Indirect data memory address pointer xxxx xxxx uuuu uuuu
PORTA Data Direction Register --11 1111 --11 1111
Write Buffer for the upper 5 bits of the Program Counter ---0 0000 ---0 0000
GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u
—ADIE
PCFG2 PCFG1 PCFG0 ---- -000 ---- -000
RP1
(5)
RP0 TO PD ZDCC0001 1xxx 000q quuu
(3)
SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000
2
C mode) Address Register 0000 0000 0000 0000
PSR/WUA B F 0000 0000 0000 0000
Val ue on:
POR,
BOR
Legend: x = unknown, u = unchanged, q = value depends on condition, - = unimplemented, read as '0',
Shaded locations are unimplemented, read as '0'.
Note 1: These registers can be addressed from either bank.
2: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for PC<12:8> whose contents
are transferred to the upper byte of the program counter.
3: A/D not implemented on the PIC16C62B, maintain as ’0’. 4: Other (non power-up) resets include: external reset through MCLR
and the Watchdog Timer Reset.
5: The IRP and RP1 bits are reserved. Always maintain these bits clear. 6: On any device reset, these pins are configured as inputs. 7: This is the value that will be in the port output latch.
Value on all
other resets
(4)
DS35008C-page 10 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
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, the write to these three bits is dis­abled. These bits are set or cleared according to the device logic. The TO result of an instruction with the STATUS register as destination may be different than intended.
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).
and PD bits are not writable. The
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 the "Instruction Set Summary."
Note 1: The IRP and RP1 bits are reserved. Main-
tain these bits clear to ensure upward compatibility with future products.
Note 2: The C and DC bits operate as a borrow
and digit borrow bit, respectively, in sub­traction. See the SUBLW and SUBWF instructions.
REGISTER 2-1: STATUS REGISTER (ADDRESS 03h, 83h)
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 R = Readable bit
bit7 bit0
bit 7: IRP: Register Bank Select bit (used for indirect addressing)
(reserved, maintain clear)
bit 6-5: RP1:RP0: Register Bank Select bits (used for direct addressing)
01 = Bank 1 (80h - FFh) 00 = Bank 0 (00h - 7Fh)
Each bank is 128 bytes Note: RP1 is reserved, maintain clear
bit 4: TO
bit 3: PD
bit 2: Z: Zero bit
bit 1: DC: Digit carry/borrow
bit 0: C: Carry/borrow
: Time-out bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred
: Power-down bit
1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction
1 = The result of an arithmetic or logic operation is zero 0 = The result of an arithmetic or logic operation is not zero
bit (ADDWF, ADDLW,SUBLW,SUBWF instructions) (for borrow, the polarity is reversed) 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 (ADDWF, ADDLW,SUBLW,SUBWF instructions) (for borrow, the polarity is reversed) 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
W = Writable bit U = Unimplemented bit, read as ‘0’
- n = Value at POR reset
Note: For borrow second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low order bit of the source register.
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 11
, the polarity is reversed. A subtraction is executed by adding the two’s complement of the
PIC16C62B/72A
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
Bit Value TMR0 Rate WDT Rate
2.2.2.2 OPTION_REG REGISTER
The OPTION_REG register is a readable and writable register, which contains various control bits to configure the TMR0 prescaler/WDT postscaler (single assign­able register known as the prescaler), the External INT Interrupt, TMR0 and the weak pull-ups on PORTB.
REGISTER 2-2: OPTION_REG REGISTER (ADDRESS 81h)
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
bit7 bit0
bit 7: RBPU: PORTB Pull-up Enable bit
bit 6: INTEDG: Interrupt Edge Select bit
bit 5: T0CS: TMR0 Clock Source Select bit
bit 4: T0SE: TMR0 Source Edge Select bit
bit 3: PSA: Prescaler Assignment bit
bit 2-0: PS2:PS0: Prescaler Rate Select bits
INTEDG T0CS T0SE PSA PS2 PS1 PS0 R = Readable bit
1 = PORTB pull-ups are disabled 0 = PORTB pull-ups are enabled for all PORTB inputs
1 = Interrupt on rising edge of RB0/INT pin 0 = Interrupt on falling edge of RB0/INT pin
1 = Transition on RA4/T0CKI pin 0 = Internal instruction cycle clock (CLKOUT)
1 = Increment on high-to-low transition on RA4/T0CKI pin 0 = Increment on low-to-high transition on RA4/T0CKI pin
1 = Prescaler is assigned to the WDT 0 = Prescaler is assigned to the Timer0 module
Note: To achieve a 1:1 prescaler assignment for
the TMR0 register, assign the prescaler to the Watchdog Timer.
W = Writable bit
- n = Value at POR reset
DS35008C-page 12 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
2.2.2.3 INTCON REGISTER
The INTCON Register is a readable and writable regis­ter, which contains various interrupt enable and flag bits for the TMR0 register overflow, RB Port change and External RB0/INT pin interrupts.
Note: Interrupt flag bits are 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.
REGISTER 2-3: INTCON REGISTER (ADDRESS 0Bh, 8Bh)
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 T0IE INTE RBIE T0IF INTF RBIF R = Readable bit
bit7 bit0
bit 7: GIE: Global Interrupt Enable bit
1 = Enables all un-masked interrupts 0 = Disables all interrupts
bit 6: PEIE: Peripheral Interrupt Enable bit
1 = Enables all un-masked peripheral interrupts 0 = Disables all peripheral interrupts
bit 5: T0IE: TMR0 Overflow Interrupt Enable bit
1 = Enables the TMR0 interrupt 0 = Disables the TMR0 interrupt
bit 4: IINTE: 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: T0IF: TMR0 Overflow Interrupt Flag bit
1 = TMR0 register has overflowed (software must clear bit) 0 = TMR0 register did not overflow
bit 1: INTF: RB0/INT External Interrupt Flag bit
1 = The RB0/INT external interrupt occurred (software must clear bit) 0 = The RB0/INT external interrupt did not occur
bit 0: RBIF: RB Port Change Interrupt Flag bit
1 = At least one of the RB7:RB4 input pins have changed state (clear by reading PORTB) 0 = None of the RB7:RB4 input pins have changed state
W = Writable bit
- n = Value at POR reset
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 13
PIC16C62B/72A
2.2.2.4 PIE1 REGISTER
This register contains the individual enable bits for the
Note: Bit PEIE (INTCON<6>) must be set to
enable any peripheral interrupt.
peripheral interrupts.
REGISTER 2-4: PIE1 REGISTER (ADDRESS 8Ch)
U-0 R/W-0 U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0
ADIE
bit7 bit0
bit 7: Unimplemented: Read as ‘0’
bit 6: ADIE
bit 5-4: Unimplemented: Read as ‘0’
bit 3: SSPIE: Synchronous Serial Port Interrupt Enable bit
bit 2: CCP1IE: CCP1 Interrupt Enable bit
bit 1: TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
bit 0: TMR1IE: TMR1 Overflow Interrupt Enable bit
(1)
SSPIE CCP1IE TMR2IE TMR1IE R = Readable bit
(1)
: A/D Converter Interrupt Enable bit
1 = Enables the A/D interrupt 0 = Disables the A/D interrupt
1 = Enables the SSP interrupt 0 = Disables the SSP interrupt
1 = Enables the CCP1 interrupt 0 = Disables the CCP1 interrupt
1 = Enables the TMR2 to PR2 match interrupt 0 = Disables the TMR2 to PR2 match interrupt
1 = Enables the TMR1 overflow interrupt 0 = Disables the TMR1 overflow interrupt
W = Writable bit U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
Note 1: The PIC16C62B does not have an A/D module. This bit location is reserved on these devices. Always maintain this
bit clear.
DS35008C-page 14 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
2.2.2.5 PIR1 REGISTER
This register contains the individual flag bits for the Peripheral interrupts.
Note: Interrupt flag bits are 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.
REGISTER 2-5: PIR1 REGISTER (ADDRESS 0Ch)
U-0 R/W-0 U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0
ADIF
bit7 bit0
bit 7: Unimplemented: Read as ‘0’
bit 6: ADIF
bit 5-4: Unimplemented: Read as ‘0’
bit 3: SSPIF: Synchronous Serial Port Interrupt Flag bit
bit 2: CCP1IF: CCP1 Interrupt Flag bit
bit 1: TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
bit 0: TMR1IF: TMR1 Overflow Interrupt Flag bit
(1)
(1)
SSPIF CCP1IF TMR2IF TMR1IF R = Readable bit
: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed (must be cleared in software) 0 = The A/D conversion is not complete
1 = The transmission/reception is complete (must be cleared in software) 0 = Waiting to transmit/receive
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
1 = TMR2 to PR2 match occurred (must be cleared in software) 0 = No TMR2 to PR2 match occurred
1 = TMR1 register overflowed (must be cleared in software) 0 = TMR1 register did not overflow
W = Writable bit U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
Note 1: The PIC16C62B does not have an A/D module. This bit location is reserved on these devices. Always maintain this
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 15
bit clear.
PIC16C62B/72A
2.2.2.6 PCON REGISTER
The Power Control register (PCON) contains flag bits to allow differentiation between a Power-on Reset (POR), Brown-Out Reset (BOR) and resets from other sources. .
Note: On Power-on Reset, the state of the BOR
bit is unknown and is not predictable. If the BODEN bit in the configuration word is set, the user must first set the BOR bit on a POR, and check it on subsequent resets. If BOR is cleared while POR remains set, a Brown-out reset has occurred. If the BODEN bit is clear, the BOR bit may be ignored.
REGISTER 2-6: PCON REGISTER (ADDRESS 8Eh)
U-0 U-0 U-0 U-0 U-0 U-0 R/W-0 R/W-q
—PORBOR R = Readable bit
bit7 bit0
bit 7-2: Unimplemented: Read as '0'
bit 1: POR
bit 0: BOR
: 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)
: 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)
W = Writable bit U = Unimplemented bit,
- n = Value at POR reset
read as ‘0’
DS35008C-page 16 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
2.3 PCL and PCLATH
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 and is readable and writable. The high byte is called the PCH register. This register contains the PC<12:8> bits and is not directly accessible. All updates to the PCH regis­ter go through the PCLATH register.
2.3.1 STACK
The stack allows any combination of up to 8 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 hardware stack. The stack space is not part of either program or data space and the stack pointer is not accessible. The PC is PUSHed onto the stack when a CALL instruction is executed or an interrupt causes a branch. The stack is POPed in the event of a RETURN, RETLW or a RET- FIE instruction execution. PCLATH is not modified when the stack is PUSHed or POPed.
After the stack has been PUSHed 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).
2.4 Program Memory Paging
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 bit of the address is provided by PCLATH<3>. The user must ensure that the page select bit is programmed to address the proper pro­gram memory page. If a return from a CALL instruction (or interrupt) is executed, the entire 13-bit PC is popped from the stack. Therefore, manipulation of the PCLATH<3> bit is not required for the return instruc­tions.
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 17
PIC16C62B/72A
Note 1: Maintain clear for upward compatibility with future products.
2: Not implemented.
Data Memory
Indirect AddressingDirect Addressing
bank select location select
RP1:RP0 6
0
from opcode
IRP FSR register
7
0
bank select
location select
00 01 10 11
Bank 0 Bank 1 Bank 2 Bank 3
not used
FFh
80h
7Fh
00h
17Fh
100h
1FFh
180h
(1)
(1)
(2) (2)
2.5 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
).
Reading INDF itself indirectly (FSR = 0) will produce 00h. Writing to the INDF register indirectly results in a no-operation (although STATUS bits may be affected).
A simple program to clear RAM locations 20h-2Fh using indirect addressing is shown in Example 2-1.
FIGURE 2-3: DIRECT/INDIRECT ADDRESSING
EXAMPLE 2-1: HOW TO CLEAR RAM
USING INDIRECT ADDRESSING
movlw 0x20 ;initialize pointer movwf FSR ; to RAM NEXT clrf INDF ;clear INDF register incf FSR ;inc pointer btfss FSR,4 ;all done? goto NEXT ;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 2-3. However, IRP is not used in the PIC16C62B/72A.
DS35008C-page 18 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
Data Bus
QD
Q
CK
QD
Q
CK
QD
EN
P
N
WR Por t
WR TRIS
Data Latch
TRIS Latch
RD TRIS
RD PORT
V
SS
VDD
I/O pin
(1)
Note 1: I/O pins have protection diodes to VDD and
V
SS.
Analog input mode
TTL input buffer
To A/D Converter (72A only)
(72A
only)
Data Bus
WR PORT
WR TRIS
RD PORT
Data Latch
TRIS Latch
RD TRIS
Schmitt Trigger input buffer
N
V
SS
I/O pin
(1)
TMR0 clock input
QD
Q
CK
QD
Q
CK
EN
QD
EN
Note 1: I/O pin has protection diodes to VSS only.
3.0 I/O PORTS
Some I/O port pins 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
®
MCU Mid-Range Reference Manual, (DS33023).
PIC
3.1 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).
The PORTA register reads the state 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.
Pin RA5 is multiplexed with the SSP to become the RA5/SS
On the PIC16C72A device, 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).
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.
pin.
Note: On a Power-on Reset, pins with analog
functions are configured as analog inputs with digital input buffers disabled . A digital read of these pins will return ’0’.
FIGURE 3-1: BLOCK DIAGRAM OF
RA3:RA0 AND RA5 PINS
FIGURE 3-2: BLOCK DIAGRAM OF
RA4/T0CKI PIN
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 19
PIC16C62B/72A
TABLE 3-1 PORTA FUNCTIONS
Name Bit# Buffer Function
RA0/AN0 bit0 TTL Input/output or analog input
RA1/AN1 bit1 TTL Input/output or analog input
RA2/AN2 bit2 TTL Input/output or analog input
RA3/AN3/VREF bit3 TTL Input/output or analog input
Input/output or external clock input for Timer0
RA4/T0CKI bit4 ST
Output is open drain type
RA5/SS/AN4 bit5 TTL Input/output or slave select input for synchronous serial port or analog input Legend: TTL = TTL input, ST = Schmitt Trigger input
Note 1: The PIC16C62B does not implement the A/D module.
TABLE 3-2 SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
(1)
(1)
(1)
(1)
or VREF
(1)
(1)
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
05h PORTA
(for PIC16C72A only)
05h PORTA
(for PIC16C62B only)
85h TRISA
9Fh ADCON1
(1)
RA5 RA4 RA3 RA2 RA1 RA0 --0x 0000 --0u 0000
RA5 RA4 RA3 RA2 RA1 RA0 --xx xxxx --uu uuuu
PORTA Data Direction Register --11 1111 --11 1111
—PCFG2PCFG1PCFG0---- -000 ---- -000
Value on
POR,
BOR
Value on all
other resets
Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by PORTA.
Note 1: The PIC16C62B does not implement the A/D module. Maintain this register clear.
DS35008C-page 20 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
Data Latch
RBPU
(2)
P
V
DD
QD
CK
QD
CK
QD
EN
Data Bus
WR Port
WR TRIS
RD TRIS
RD Port
weak pull-up
RD Port
RB0/INT
I/O pin
(1)
TTL Input Buffer
Note 1: I/O pins have diode protection to V
DD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU
bit (OPTION_REG<7>).
Schmitt Trigger Buffer
TRIS Latch
Data Latch
From other
RBPU
(2)
P
V
DD
I/O
QD
CK
QD
CK
QD
EN
QD
EN
Data Bus
WR Port
WR TRIS
Set RBIF
TRIS Latch
RD TRIS
RD Port
RB7:RB4 pins
weak pull-up
RD Port
Latch
TTL Input Buffer
pin
(1)
Note 1: I/O pins have diode protection to VDD and VSS.
ST
Buffer
RB7:RB6 in serial programming mode
Q3
Q1
2: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU
bit (OPTION_REG<7>).
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).
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_REG<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
Four of PORTB’s pins, RB7:RB4, have an interrupt on change 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) are compared with the old value latched on the last read of PORTB. The “mismatch” outputs of RB7:RB4 are OR’ed 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) Any read or write of PORTB. This will end the
mismatch condition.
b) 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.
RB0/INT is an external interupt pin and is configured using the INTEDG bit (OPTION_REG<6>). RB0/INT is discussed in detail in Section 10.10.1.
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 21
FIGURE 3-4: BLOCK DIAGRAM OF
RB7:RB4 PINS
PIC16C62B/72A
TABLE 3-3 PORTB FUNCTIONS
Name Bit# Buffer Function
RB0/INT bit0 TTL/ST
RB1 bit1 TTL Input/output pin. Internal software programmable weak pull-up. RB2 bit2 TTL Input/output pin. Internal software programmable weak pull-up. RB3 bit3 TTL Input/output pin. Internal software programmable weak pull-up. RB4 bit4 TTL Input/output pin (with interrupt on change).
RB5 bit5 TTL Input/output pin (with interrupt on change).
RB6 bit6 TTL/ST
RB7 bit7 TTL/ST
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
(1)
Input/output pin or external interrupt input. Internal software programmable weak pull-up.
Internal software programmable weak pull-up.
Internal software programmable weak pull-up.
(2)
Input/output pin (with interrupt on change). Internal software programmable weak pull-up. Serial programming clock.
(2)
Input/output pin (with interrupt on change). Internal software programmable weak pull-up. Serial programming data.
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
06h PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 xxxx xxxx uuuu uuuu
86h TRISB PORTB Data Direction Register 1111 1111 1111 1111
81h OPTION_REG RBPU
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTB.
INTEDG T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111
Value on:
POR,
BOR
Value on all
other resets
DS35008C-page 22 Preliminary 1998-2013 Microchip Technology Inc.
3.3 PORTC and the TRISC Register
PORT/PERIPHERAL Select
(2)
Data Bus
WR PORT
WR TRIS
RD
Data Latch
TRIS Latch
RD TRIS
Schmitt Trigger
QD
Q
CK
QD
EN
Peripheral Data Out
0
1
QD
Q
CK
P
N
V
DD
VSS
PORT
Peripheral OE
(3)
Peripheral input
I/O pin
(1)
Note 1: I/O pins have diode protection to VDD and VSS.
2: Port/Peripheral select signal selects between port
data and peripheral output.
3: Peripheral OE (output enable) is only activated if
peripheral select is active.
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 maybe 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.
PIC16C62B/72A
FIGURE 3-5: PORTC BLOCK DIAGRAM
(PERIPHERAL OUTPUT OVERRIDE)
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 23
PIC16C62B/72A
TABLE 3-5 PORTC FUNCTIONS
bit0
Buffer
Function
Typ e
ST Input/output port pin or Timer1 oscillator output/Timer1 clock input Yes
output
RC3 can also be the synchronous serial clock for both SPI and I modes.
2
RC4 can also be the SPI Data In (SPI mode) or data I/O (I
C mode).
Name Bit#
RC0/T1OSO/T1CKI
RC1/T1OSI bit1 ST Input/output port pin or Timer1 oscillator input Yes
RC2/CCP1 bit2 ST Input/output port pin or Capture1 input/Compare1 output/PWM1
RC3/SCK/SCL bit3 ST
RC4/SDI/SDA bit4 ST
RC5/SDO bit5 ST Input/output port pin or Synchronous Serial Port data output No
RC6 bit6 ST Input/output port pin No
RC7 bit7 ST Input/output port pin No
Legend: ST = Schmitt Trigger input
2
C
TRISC
Override
No
No
No
TABLE 3-6 SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
Value on:
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
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.
POR,
BOR
Value on all
other resets
DS35008C-page 24 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
Note 1: T0CS, T0SE, PSA, PS2:PS0 (OPTION_REG<5:0>).
2: The prescaler is shared with Watchdog Timer (refer to Figure 4-2 for detailed block diagram).
RA4/T0CKI
T0SE
0
1
1
0
pin
T0CS
FOSC/4
Programmable
Prescaler
Sync with
Internal
clocks
TMR0
PSout
(T
CY delay)
PSout
Data Bus
8
PSA
PS2, PS1, PS0
Set interrupt
flag bit T0IF
on overflow
3
4.0 TIMER0 MODULE
The Timer0 module timer/counter has the following fea­tures:
• 8-bit timer/counter
- Read and write
- INT on overflow
• 8-bit software programmable prescaler
• INT or EXT clock select
- EXT clock edge select
Figure 4-1 is a simplified block diagram of the Timer0 module.
Additional information on timer modules is available in the PIC (DS33023).
4.1 Timer0 Operation
Timer0 can operate as a timer or as a counter.
Timer mode is selected by clearing bit T0CS (OPTION_REG<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.
Counter mode is selected by setting bit T0CS (OPTION_REG<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_REG<4>). Clearing bit T0SE selects the ris­ing edge. Restrictions on the external clock input are discussed below.
When an external clock input is used for Timer0, it must meet certain requirements. The requirements ensure the external clock can be synchronized with the internal phase clock (T incrementing of Timer0 after synchronization.
®
MCU Mid-Range Reference Manual,
OSC). Also, there is a delay in the actual
Additional information on external clock requirements is available in the Electrical Specifications section of this manual, and in the PIC
®
MCU Mid-Range Refer-
ence Manual, (DS33023).
4.2 Prescaler
An 8-bit counter is available as a prescaler for the Timer0 module, or as a postscaler for the Watchdog Timer, respectively (Figure 4-2). For simplicity, this counter is being referred to as “prescaler” throughout this data sheet. There is only one prescaler available which is shared between the Timer0 module and the Watchdog Timer. A prescaler assignment for the Timer0 module means that there is no prescaler for the Watchdog Timer, and vice-versa.
The prescaler is not readable or writable.
The PSA and PS2:PS0 bits (OPTION_REG<3:0>) determine the prescaler assignment and prescale ratio.
Clearing bit PSA will assign the prescaler to the Timer0 module. When the prescaler is assigned to the Timer0 module, prescale values of 1:2, 1:4, ..., 1:256 are selectable.
Setting bit PSA will assign the prescaler to the Watch­dog Timer (WDT). When the prescaler is assigned to the WDT, prescale values of 1:1, 1:2, ..., 1:128 are selectable.
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 WDT.
Note: Writing to TMR0 when the prescaler is
assigned to Timer0 will clear the prescaler count, but will not change the prescaler assignment or ratio.
FIGURE 4-1: TIMER0 BLOCK DIAGRAM
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 25
PIC16C62B/72A
RA4/T0CKI
T0SE
pin
M U
X
CLKOUT (= Fosc/4)
SYNC
2
T
CY
TMR0 reg
8-bit Prescaler
8 - to - 1MUX
M
U X
M U X
Watchdog
Timer
PSA
0
1
0
1
WDT
Time-out
PS2:PS0
8
Note: T0CS, T0SE, PSA, PS2:PS0 are (OPTION_REG<5:0>).
PSA
WDT Enable bit
M U
X
0
1
0
1
Data Bus
Set flag bit T0IF
on Overflow
8
PSA
T0CS
Prescaler
4.2.1 SWITCHING PRESCALER ASSIGNMENT
The prescaler assignment is fully under software con­trol, (i.e., it can be changed “on-the-fly” during program execution).
Note: To avoid an unintended device RESET, a
specific instruction sequence (shown in the
®
MCU Mid-Range Reference Manual,
PIC DS33023) must be executed when chang­ing the prescaler assignment from Timer0
4.3 Timer0 Interrupt
The TMR0 interrupt is generated when the TMR0 reg­ister overflows from FFh to 00h. This overflow sets bit T0IF (INTCON<2>). The interrupt can be masked by clearing bit T0IE (INTCON<5>). Bit T0IF 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.
to the WDT. This sequence must be fol­lowed even if the WDT is disabled.
FIGURE 4-2: BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER
TABLE 4-1 REGISTERS ASSOCIATED WITH TIMER0
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
01h TMR0 Timer0 module’s register xxxx xxxx uuuu uuuu
0Bh,8Bh INTCON GIE
81h OPTION_REG
85h TRISA
Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by Timer0.
DS35008C-page 26 Preliminary 1998-2013 Microchip Technology Inc.
RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111
PORTA Data Direction Register --11 1111 --11 1111
PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u
Val ue o n:
POR,
BOR
Value on all
other resets
PIC16C62B/72A
5.0 TIMER1 MODULE
The Timer1 module timer/counter has the following fea­tures:
• 16-bit timer/counter
• Readable and writable
• Internal or external clock select
• Interrupt on overflow from FFFFh to 0000h
• Reset from CCP module trigger
Timer1 has a control register, shown in Register 5-1. Timer1 can be enabled/disabled by setting/clearing control bit TMR1ON (T1CON<0>).
Figure 5-1 is a simplified block diagram of the Timer1 module.
Additional information on timer modules is available in the PIC (DS33023).
®
MCU Mid-Range Reference Manual,
5.1 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>).
In timer mode, Timer1 increments every instruction cycle. In counter mode, it increments on every rising edge of the external clock input.
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.
Timer1 also has an internal “reset input”. This reset can be generated by the CCP module as a special event trigger (Section 7.0).
REGISTER 5-1:T1CON: TIMER1 CONTROL REGISTER (ADDRESS 10h)
U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
bit7 bit0
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 (TRISC<1:0> ignored) 0 = Oscillator is shut off
(The oscillator is turned off to reduce power drain
bit 2: T1SYNC
T
1 = Do not synchronize external clock input 0 = Synchronize external clock input
T 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 (F
bit 0: TMR1ON: Timer1 On bit
1 = Enables Timer1 0 = Stops Timer1
: Timer1 External Clock Input Synchronization Control bit
MR1CS = 1
MR1CS = 0
OSC/4)
R = Readable bit W = Writable bit U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 27
PIC16C62B/72A
TMR1H
TMR1L
T1OSC
T1SYNC
TMR1CS
T1CKPS1:T1CKPS0
SLEEP input
T1OSCEN Enable
Oscillator
(1)
FOSC/4
Internal Clock
TMR1ON
on/off
Prescaler
1, 2, 4, 8
Synchronize
det
1
0
0
1
Synchronized
clock input
2
RC0/T1OSO/T1CKI
RC1/T1OSI
Note 1: When the T1OSCEN bit is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
Set flag bit TMR1IF on Overflow
TMR1
FIGURE 5-1: TIMER1 BLOCK DIAGRAM
DS35008C-page 28 Preliminary 1998-2013 Microchip Technology Inc.
PIC16C62B/72A
5.2 Timer1 Oscillator
A crystal oscillator circuit is built-in between pins T1OSI (input) and T1OSO (amplifier output). It is enabled by setting control bit T1OSCEN (T1CON<3>). When the Timer1 oscillator is enabled, RC0 and RC1 pins become T1OSO and T1OSI inputs, overriding TRISC<1:0>.
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.
TABLE 5-1 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.
Crystals Tested:
32.768 kHz Epson C-001R32.768K-A 20 PPM 100 kHz Epson C-2 100.00 KC-P 20 PPM 200 kHz STD XTL 200.000 kHz 20 PPM 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.
5.3 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 and is latched in interrupt flag bit TMR1IF (PIR1<0>). This interrupt can be enabled by setting TMR1 interrupt enable bit TMR1IE (PIE1<0>).
5.4 Resetting Timer1 using a CCP Trigger Output
If the CCP module is configured in compare mode to generate a “special event trigger" (CCP1M3:CCP1M0 = 1011), this signal will reset Timer1 and start an A/D conversion (if the A/D module is enabled).
Note: The special event trigger 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.
TABLE 5-2 REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0Bh,8Bh INTCON GIE PEIE
0Ch PIR1
8Ch PIE1
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
Legend: x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by the Timer1 module.
1998-2013 Microchip Technology Inc. Preliminary DS35008C-page 29
ADIF SSPIF CCP1IF TMR2IF TMR1IF
ADIE SSPIE CCP1IE TMR2IE TMR1IE
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
T0IE INTE RBIE T0IF INTF RBIF
Value on
POR,
BOR
0000 000x 0000 000u
-0-- 0000 -0-- 0000
-0-- 0000 -0-- 0000
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
--00 0000 --uu uuuu
Value on all other
resets
PIC16C62B/72A
NOTES:
DS35008C-page 30 Preliminary 1998-2013 Microchip Technology Inc.
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