PIC16F872 Datasheet, PDF (24/160 Pages) Microchip Technology – 28-Pin, 8-Bit CMOS FLASH Microcontroller

PIC16F872
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 or VREF
RA4/T0CKI
bit4
ST Input/output or external clock input for Timer0
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.
TABLE 3-2: SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3
Bit 2
Bit 1
Bit 0
Value on: Value on all
POR,
other
BOR
resets
05h
PORTA
—
— RA5 RA4 RA3
RA2
RA1 RA0 --0x 0000 --0u 0000
85h
TRISA
— — PORTA Data Direction Register
--11 1111 --11 1111
9Fh
ADCON1 ADFM —
—
— PCFG3 PCFG2 PCFG1 PCFG0 --0- 0000 --0- 0000
Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by PORTA.
Note: When using the SSP module in SPI slave mode and SS enabled, the A/D converter must be set to one of
the following modes where PCFG<3:0> = 0100,0101, 011x, 1101, 1110, 1111.
DS30221A-page 24
Preliminary
© 1999 Microchip Technology Inc.