2001 Microchip Technology Inc.
DS30292C-page 15
PIC16F87X
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
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 features 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
Details
on
page:
Bank 0
00h(3)
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
0000 0000
01h
TMR0
Timer0 Module Register
xxxx xxxx
02h(3)
PCL
Program Counter (PC) Least Significant Byte
0000 0000
03h(3)
STATUS
IRP
RP1
RP0
TO
PD
ZDC
C
0001 1xxx
04h(3)
FSR
Indirect Data Memory Address Pointer
xxxx xxxx
05h
PORTA
—
PORTA Data Latch when written: PORTA pins when read
--0x 0000
06h
PORTB
PORTB Data Latch when written: PORTB pins when read
xxxx xxxx
07h
PORTC
PORTC Data Latch when written: PORTC pins when read
xxxx xxxx
08h(4)
PORTD
PORTD Data Latch when written: PORTD pins when read
xxxx xxxx
09h(4)
PORTE
—
RE2
RE1
RE0
---- -xxx
0Ah(1,3)
—
Write Buffer for the upper 5 bits of the Program Counter
---0 0000
0Bh(3)
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0Ch
PIR1
PSPIF(3)
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
0000 0000
0Dh
PIR2
—
(5)
—
EEIF
BCLIF
—
CCP2IF
-r-0 0--0
0Eh
TMR1L
Holding register for the Least Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
0Fh
TMR1H
Holding register for the Most Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
10h
T1CON
—
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
--00 0000
11h
TMR2
Timer2 Module Register
0000 0000
12h
T2CON
—
TOUTPS3
TOUTPS2
TOUTPS1
TOUTPS0
TMR2ON
T2CKPS1
T2CKPS0 -000 0000
13h
SSPBUF
Synchronous Serial Port Receive Buffer/Transmit Register
xxxx xxxx
14h
SSPCON
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000
15h
CCPR1L
Capture/Compare/PWM Register1 (LSB)
xxxx xxxx
16h
CCPR1H
Capture/Compare/PWM Register1 (MSB)
xxxx xxxx
17h
CCP1CON
—
CCP1X
CCP1Y
CCP1M3
CCP1M2
CCP1M1
CCP1M0
--00 0000
18h
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
19h
TXREG
USART Transmit Data Register
0000 0000
1Ah
RCREG
USART Receive Data Register
0000 0000
1Bh
CCPR2L
Capture/Compare/PWM Register2 (LSB)
xxxx xxxx
1Ch
CCPR2H
Capture/Compare/PWM Register2 (MSB)
xxxx xxxx
1Dh
CCP2CON
—
CCP2X
CCP2Y
CCP2M3
CCP2M2
CCP2M1
CCP2M0
--00 0000
1Eh
ADRESH
A/D Result Register High Byte
xxxx xxxx
1Fh
ADCON0
ADCS1
ADCS0
CHS2
CHS1
CHS0
GO/DONE
—
ADON
0000 00-0
Legend:
x
= unknown, u = unchanged, q = value depends on condition, - = unimplemented, read as '0', r = reserved.
Shaded locations are unimplemented, read as ‘0’.
Note 1: 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.
2: Bits PSPIE and PSPIF are reserved on PIC16F873/876 devices; always maintain these bits clear.
3: These registers can be addressed from any bank.
4: PORTD, PORTE, TRISD, and TRISE are not physically implemented on PIC16F873/876 devices; read as ‘0’.
5: PIR2<6> and PIE2<6> are reserved on these devices; always maintain these bits clear.