
PIC16C5X
DS30453D-page 28
Preliminary
2002 Microchip Technology Inc.
6.2.2
SPECIAL FUNCTION REGISTERS
The Special Function Registers are registers used by
the CPU and peripheral functions to control the opera-
The Special 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 6-1:
SPECIAL FUNCTION REGISTER SUMMARY
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
Power-on
Reset
Details
on Page
N/A
TRIS
I/O Control Registers (TRISA, TRISB, TRISC)
1111 1111
N/A
OPTION
Contains control bits to configure Timer0 and Timer0/WDT prescaler
--11 1111
00h
INDF
Uses contents of FSR to address data memory (not a physical register)
xxxx xxxx
01h
TMR0
Timer0 Module Register
xxxx xxxx
02h(1)
PCL
Low order 8 bits of PC
1111 1111
03h
STATUS
PA2
PA1
PA0
TO
PD
ZDC
C
0001 1xxx
04h
FSR
Indirect data memory address pointer
1xxx xxxx(3)
05h
PORTA
—
RA3
RA2
RA1
RA0
---- xxxx
06h
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
07h(2)
PORTC
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
xxxx xxxx
Legend: x = unknown, u = unchanged, – = unimplemented, read as '0' (if applicable). Shaded cells = unimplemented or unused
Note
1:
The upper byte of the Program Counter is not directly accessible. See
Section 6.5 for an explanation of how to access
these bits.
2: File address 07h is a General Purpose Register on the PIC16C54, PIC16CR54, PIC16C56, PIC16CR56, PIC16C58 and
PIC16CR58.
3: These values are valid for PIC16C57/CR57/C58/CR58. For the PIC16C54/CR54/C55/C56/CR56, the value on RESET is
111x xxxx and for MCLR and WDT Reset, the value is 111u uuuu.