PIC16C63A/65B/73B/74B
TABLE 5-1:
Name
PORTA FUNCTIONS
Bit# Buffer Function
bit0
RA0/AN0(1)
RA1/AN1(1)
RA2/AN2(1)
RA3/AN3/VREF
TTL
TTL
TTL
TTL
Digital input/output or analog input.
Digital input/output or analog input.
Digital input/output or analog input.
Digital input/output or analog input or VREF.
bit1
bit2
bit3
(1)
Digital input/output or external clock input for Timer0.
Output is open drain type.
RA4/T0CKI
bit4
bit5
ST
RA5/SS/AN4(1)
TTL
Input/output or slave select input for synchronous serial port or analog input.
Legend: TTL = TTL input, ST = Schmitt Trigger input
Note 1: The A/D is not implemented on the PIC16C63A/65B. Pins will operate as digital I/O only. ADCON1 is not
implemented; maintain this register clear.
TABLE 5-2:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Value on:
POR,
BOR
Value on
all other
RESETS
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
05h
85h
PORTA
TRISA
—
—
—
—
RA5
RA4
RA3
RA2
RA1
RA0
--0x 0000 --0u 0000
--11 1111 --11 1111
PORTA Data Direction Register
(1)
9Fh
—
—
—
—
—
PCFG2 PCFG1 PCFG0 ---- -000 ---- -000
ADCON1
Legend: x= unknown, u= unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by PORTA.
Note 1: The A/D is not implemented on the PIC16C63A/65B. Pins will operate as digital I/O only. ADCON1 is not implemented;
maintain this register clear.
DS30605C-page 30
2000 Microchip Technology Inc.