
PIC16C9XX
DS30444E - page 34
1997 Microchip Technology Inc.
TABLE 5-3: PORTB FUNCTIONS
TABLE 5-4: SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Name
Bit#
Buffer
Function
RB0/INT
bit0
TTL/ST
Input/output pin or external interrupt input. Internal software
programmable weak pull-up. This buffer is a Schmitt Trigger input when
congured as the external interrupt.
RB1
bit1
TTL
Input/output pin. Internal software programmable weak pull-up.
RB2
bit2
TTL
Input/output pin. Internal software programmable weak pull-up.
RB3
bit3
TTL
Input/output pin. Internal software programmable weak pull-up.
RB4
bit4
TTL
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up.
RB5
bit5
TTL
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up.
RB6
bit6
TTL/ST
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up. Serial programming clock. This buffer is a Schmitt Trigger
input when used in serial programming mode.
RB7
bit7
TTL/ST
Input/output pin (with interrupt on change). Internal software programmable
weak pull-up. Serial programming data. This buffer is a Schmitt Trigger input
when used in serial programming mode.
Legend: TTL = TTL input, ST = Schmitt Trigger input
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
Power-on
Reset
Value on all
other resets
06h, 106h
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
uuuu uuuu
86h, 186h
TRISB
PORTB Data Direction Control Register
1111 1111
81h, 181h
OPTION
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTB.