PIC16F5X
3.2.2
SPECIAL FUNCTION REGISTERS
The Special Function Registers (SFR) are registers
used by the CPU and peripheral functions to control the
operation of the device (Table 3-1).
The Special Function Registers can be classified into
two sets. The Special Function Registers associated
with the “core” functions are described in this section.
Those related to the operation of the peripheral
features are described in the section for each
peripheral feature.
TABLE 3-1:
Address
SPECIAL FUNCTION REGISTER SUMMARY
Value on
Power-on
Reset
Details
on Page
Name
Bit 7
Bit 6
Bit 5 Bit 4 Bit 3
Bit 2 Bit 1 Bit 0
N/A
N/A
TRIS
I/O Control Registers (TRISA, TRISB, TRISC, TRISD, TRISE)
1111 1111
--11 1111
29
18
OPTION
Contains control bits to configure Timer0 and Timer0/WDT
prescaler
00h
INDF
Uses contents of FSR to address data memory (not a physical
register)
xxxx xxxx
20
01h
02h
TMR0
PCL(1)
Timer0 Module Register
Low order 8 bits of PC
xxxx xxxx
1111 1111
34
19
03h
04h
04h
04h
05h
06h
07h
08h
09h
STATUS
FSR(3)
FSR(4)
PA2
PA1
PA0
TO
PD
Z
DC
C
0001 1xxx
111x xxxx
1xxx xxxx
xxxx xxxx
17
20
20
20
29
29
29
29
29
Indirect data memory Address Pointer
Indirect data memory Address Pointer
Indirect data memory Address Pointer
FSR(5)
PORTA(6)
PORTB
PORTC(2)
PORTD(7)
—
—
—
—
RA3
RB3
RC3
RD3
—
RA2
RB2
RC2
RD2
—
RA1
RB1
RC1
RD1
—
RA0 ---- xxxx
RB0 xxxx xxxx
RC0 xxxx xxxx
RD0 xxxx xxxx
RB7
RC7
RD7
RB6
RC6
RD6
RE6
RB5
RC5
RD5
RE5
RB4
RC4
RD4
RE4
PORTE(6), (7) RE7
—
xxxx ----
Legend: Shaded cells = unimplemented or unused, – = unimplemented, read as ‘0’ (if applicable), x= unknown,
u= unchanged
Note 1: The upper byte of the Program Counter is not directly accessible. See Section 3.5 “Program Counter”
for an explanation of how to access these bits.
2: File address 07h is a General Purpose Register on the PIC16F54.
3: PIC16F54 only.
4: PIC16F57 only.
5: PIC16F59 only.
6: Unimplemented bits are read as ‘0’s.
7: File address 08h and 09h are General Purpose Registers on the PIC16F54 and PIC16F57.
DS41213D-page 16
© 2007 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
