PIC16F870_13 Datasheet, PDF (13/172 Pages) Microchip Technology – 28/40-Pin, 8-Bit CMOS FLASH Microcontrollers

PIC16F870/871
2.2.2 SPECIAL FUNCTION 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.
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.
TABLE 2-1: SPECIAL FUNCTION REGISTER SUMMARY
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⁽²⁾
Bank 0
00h⁽⁴⁾
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000 0000 0000
01h
TMR0
Timer0 Module’s Register
xxxx xxxx uuuu uuuu
02h⁽⁴⁾
PCL
Program Counter's (PC) Least Significant Byte
0000 0000 0000 0000
03h⁽⁴⁾
STATUS
IRP
RP1
RP0
TO
PD
Z
DC
C
0001 1xxx 000q quuu
04h⁽⁴⁾
FSR
Indirect Data Memory Address Pointer
xxxx xxxx uuuu uuuu
05h
PORTA
—
— PORTA Data Latch when written: PORTA pins when read
--0x 0000 --0u 0000
06h
PORTB
PORTB Data Latch when written: PORTB pins when read
xxxx xxxx uuuu uuuu
07h
08h⁽⁵⁾
09h⁽⁵⁾
0Ah^(1,4)
0Bh⁽⁴⁾
0Ch
PORTC
PORTD
PORTE
PCLATH
INTCON
PIR1
PORTC Data Latch when written: PORTC pins when read
PORTD Data Latch when written: PORTD pins when read
—
—
—
—
—
RE2
RE1
RE0
—
—
— Write Buffer for the upper 5 bits of the Program Counter
GIE
PSPIF⁽³⁾
PEIE
ADIF
T0IE
RCIF
INTE
TXIF
RBIE
—
T0IF
CCP1IF
INTF
RBIF
TMR2IF TMR1IF
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
---- -xxx ---- -uuu
---0 0000 ---0 0000
0000 000x 0000 000u
0000 -000 0000 -000
0Dh
PIR2
—
—
—
EEIF
—
—
—
— ---0 ---- ---0 ----
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
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
11h
TMR2
Timer2 Module’s Register
0000 0000 0000 0000
12h
T2CON
— TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
13h
—
Unimplemented
—
—
14h
—
Unimplemented
—
—
15h
CCPR1L
Capture/Compare/PWM Register1 (LSB)
xxxx xxxx uuuu uuuu
16h
CCPR1H
Capture/Compare/PWM Register1 (MSB)
xxxx xxxx uuuu uuuu
17h
CCP1CON
—
—
CCP1X CCP1Y CCP1M3 CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
18h
RCSTA
SPEN
RX9
SREN
CREN ADDEN
FERR
OERR RX9D 0000 000x 0000 000x
19h
TXREG
USART Transmit Data Register
0000 0000 0000 0000
1Ah
RCREG
USART Receive Data Register
0000 0000 0000 0000
1Bh
—
Unimplemented
—
—
1Ch
—
Unimplemented
—
—
1Dh
—
Unimplemented
—
—
1Eh
ADRESH
A/D Result Register High Byte
xxxx xxxx uuuu uuuu
1Fh
ADCON0
ADCS1 ADCS0 CHS2
CHS1
CHS0 GO/DONE
—
ADON 0000 00-0 0000 00-0
Legend:
Note 1:
2:
3:
4:
5:
x = unknown, u = unchanged, q = value depends on condition, - = unimplemented, read as '0', r = reserved.
Shaded locations are unimplemented, read as ‘0’.
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.
Other (non Power-up) Resets include external RESET through MCLR and Watchdog Timer Reset.
Bits PSPIE and PSPIF are reserved on the 28-pin devices; always maintain these bits clear.
These registers can be addressed from any bank.
PORTD, PORTE, TRISD and TRISE are not physically implemented on the 28-pin devices, read as ‘0’.
 2000-2013 Microchip Technology Inc.
DS30569C-page 13