Datasheet

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

conﬁgured 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 1111 1111

81h, 181h OPTION RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111

Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTB.