Datasheet

PIC18F6310/6410/8310/8410
DS39635C-page 140  2010 Microchip Technology Inc.
11.6 PORTF, LATF and TRISF Registers
PORTF is an 8-bit wide, bidirectional port. The corre-
sponding Data Direction register is TRISF. Setting a
TRISF bit (= 1) will make the corresponding PORTF pin
an input (i.e., put the corresponding output driver in a
High-Impedance mode). Clearing a TRISF bit (= 0) will
make the corresponding PORTF pin an output (i.e., put
the contents of the output latch on the selected pin).
The Output Latch register (LATF) is also memory
mapped. Read-modify-write operations on the LATF
register read and write the latched output value for
PORTF.
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 several analog peripheral
functions, including the A/D Converter and comparator
inputs, as well as the comparator outputs. Pins, RF2
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.
EXAMPLE 11-6: INITIALIZING PORTF
Note: On a Power-on Reset, RA5 and RA<3:0>
are configured as analog inputs and read
as ‘0’. RA4 is configured as a digital input.
Note 1: On a Power-on Reset, the RF<6:0> pins
are configured as inputs and read as ‘0’.
2: To configure PORTF as a digital I/O, turn
off the comparators and set the ADCON1
value.
CLRF PORTF ; Initialize PORTF by
; clearing output
; data latches
CLRF LATF ; Alternate method
; to clear output
; data latches
MOVLW 0x07 ;
MOVWF CMCON ; Turn off comparators
MOVLW 0x0F ;
MOVWF ADCON1 ; Set PORTF as digital I/O
MOVLW 0xCF ; Value used to
; initialize data
; direction
MOVWF TRISF ; Set RF3:RF0 as inputs
; RF5:RF4 as outputs
; RF7:RF6 as inputs