PIC16C62B/72A
TABLE 3-3
PORTB FUNCTIONS
Name
Bit#
Buffer
Function
RB0/INT
bit0
TTL/ST(1)
Input/output pin or external interrupt input.
Internal software programmable weak pull-up.
RB1
RB2
RB3
RB4
bit1
bit2
bit3
bit4
TTL
TTL
TTL
TTL
Input/output pin. Internal software programmable weak pull-up.
Input/output pin. Internal software programmable weak pull-up.
Input/output pin. Internal software programmable weak pull-up.
Input/output pin (with interrupt on change).
Internal software programmable weak pull-up.
RB5
RB6
RB7
bit5
bit6
bit7
TTL
Input/output pin (with interrupt on change).
Internal software programmable weak pull-up.
TTL/ST(2)
TTL/ST(2)
Input/output pin (with interrupt on change).
Internal software programmable weak pull-up. Serial programming clock.
Input/output pin (with interrupt on change).
Internal software programmable weak pull-up. Serial programming data.
Legend: TTL = TTL input, ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt.
2: This buffer is a Schmitt Trigger input when used in serial programming mode.
TABLE 3-4
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
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
06h
86h
81h
PORTB
TRISB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
PS1
RB0
PS0
xxxx xxxx
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PORTB Data Direction Register
OPTION_REG RBPU INTEDG T0CS T0SE PSA
PS2
Legend: x= unknown, u= unchanged. Shaded cells are not used by PORTB.
DS35008B-page 22
Preliminary
1999 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
