PIC18FXX20
TABLE 10-3: PORTB FUNCTIONS
Name
RB0/INT0
Bit#
Buffer
Function
bit0
TTL/ST(1) Input/output pin or external interrupt input0.
Internal software programmable weak pull-up.
RB1/INT1
bit1
bit2
bit3
TTL/ST(1) Input/output pin or external interrupt input1.
Internal software programmable weak pull-up.
RB2/INT2
TTL/ST(1) Input/output pin or external interrupt input2.
Internal software programmable weak pull-up.
RB3/CCP2(3)/INT3
TTL/ST(4) Input/output pin, or external interrupt input3. Capture2 input/Compare2
output/PWM output (when CCP2MX configuration bit is enabled, all
PIC18F8X20 Operating modes except Microcontroller mode).
Internal software programmable weak pull-up.
RB4/KBI0
bit4
bit5
TTL
Input/output pin (with interrupt-on-change).
Internal software programmable weak pull-up.
RB5/KBI1/PGM
TTL/ST(2) Input/output pin (with interrupt-on-change).
Internal software programmable weak pull-up.
Low voltage ICSP enable pin.
RB6/KBI2/PGC
RB7/KBI3/PGD
bit6
bit7
TTL/ST(2) Input/output pin (with interrupt-on-change).
Internal software programmable weak pull-up.
Serial programming clock.
TTL/ST(2) 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.
3: RC1 is the alternate assignment for CCP2 when CCP2MX is not set (all Operating modes except
Microcontroller mode).
4: This buffer is a Schmitt Trigger input when configured as the CCP2 input.
TABLE 10-4: SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Value on
Value on
all other
RESETS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
PORTB
LATB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
1111 1111 1111 1111
0000 0000 0000 0000
LATB Data Output Register
TRISB
INTCON
PORTB Data Direction Register
GIE/
GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF INT0IF
RBIF
INTCON2
INTCON3
RBPU
INTEDG0 INTEDG1 INTEDG2 INTEDG3 TMR0IP INT3IP
INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF
RBIP
1111 1111 1111 1111
1100 0000 1100 0000
INT2IP
INT1IF
Legend: x= unknown, u= unchanged. Shaded cells are not used by PORTB.
DS39609A-page 108
Advance Information
2003 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
