Microchip Technology MA180025 データシート

DS39933D-page 130

 2010 Microchip Technology Inc.

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. 

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.

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.

CLRF

PORTF

; Initialize PORTF by

; clearing output

; data latches

CLRF

LATF

; Alternate method

; to clear output

; data latches

MOVLW

07h

; 

MOVWF

CMCON

; Turn off comparators

MOVLW

0Fh

; 

MOVWF

ADCON1

; Set PORTF as digital I/O

MOVLW

0CEh

; Value used to

; initialize data 

; direction 

MOVWF

TRISF

; Set RF3:RF1 as inputs

; RF5:RF4 as outputs 

; RF7:RF6 as inputs