PIC18F87J90 Datasheet, PDF (130/450 Pages) Microchip Technology – 64/80-Pin, High-Performance Microcontrollers with LCD Driver and nanoWatt Technology

PIC18F87J90 FAMILY
10.7 PORTF, LATF and TRISF Registers
PORTF is a 7-bit wide, bidirectional port. The
corresponding Data Direction and Output Latch registers
are TRISF and LATF. All pins on PORTF are
implemented with Schmitt Trigger input buffers. Each pin
is individually configurable as an input or output.
PORTF is multiplexed with analog peripheral functions,
as well as LCD segments. Pins, RF1 through RF6, may
be used as comparator inputs or outputs by setting the
appropriate bits in the CMCON register. To use
RF<6:3> as digital inputs, it is also necessary to turn off
the comparators.
Note 1: On device Resets, pins, RF<6:1>, are
configured as analog inputs and are read
as ‘0’.
2: To configure PORTF as digital I/O, turn off
the comparators and set the ADCON1
value.
PORTF is also multiplexed with LCD segment drives
controlled by bits in the LCDSE2 and LCDSE3
registers. I/O port functions are only available when the
segments are disabled.
EXAMPLE 10-6: INITIALIZING PORTF
CLRF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
PORTF
LATF
07h
CMCON
0Fh
ADCON1
0CEh
TRISF
; Initialize PORTF by
; clearing output
; data latches
; Alternate method
; to clear output
; data latches
;
; Turn off comparators
;
; Set PORTF as digital I/O
; Value used to
; initialize data
; direction
; Set RF3:RF1 as inputs
; RF5:RF4 as outputs
; RF7:RF6 as inputs
DS39933D-page 130
 2010 Microchip Technology Inc.