PIC18F23K20 Datasheet, PDF (125/420 Pages) Microchip Technology – 28/40/44-Pin Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology

10.4 PORTC, TRISC and LATC
Registers
PORTC is an 8-bit wide, bidirectional port. The corre-
sponding data direction register is TRISC. Setting a
TRISC bit (= 1) will make the corresponding PORTC
pin an input (i.e., disable the output driver). Clearing a
TRISC bit (= 0) will make the corresponding PORTC
pin an output (i.e., enable the output driver and put the
contents of the output latch on the selected pin).
The Data Latch register (LATC) is also memory
mapped. Read-modify-write operations on the LATC
register read and write the latched output value for
PORTC.
PORTC is multiplexed with several peripheral functions
(Table 10-5). The pins have Schmitt Trigger input buff-
ers. RC1 is the default configuration for the CCP2
peripheral pin. The CCP2 function can be relocated to
the RB3 pin by clearing the CCP2MX bit of Configura-
tion Word CONFIG3H. The default state of the
CCP2MX Configuration bit is ‘1’.
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTC pin. The
EUSART and MSSP peripherals override the TRIS bit
to make a pin an output or an input, depending on the
peripheral configuration. Refer to the corresponding
peripheral section for additional information.
Note: On a Power-on Reset, these pins are con-
figured as digital inputs.
The contents of the TRISC register are affected by
peripheral overrides. Reading TRISC always returns
the current contents, even though a peripheral device
may be overriding one or more of the pins.
PIC18F2XK20/4XK20
EXAMPLE 10-3: INITIALIZING PORTC
CLRF
CLRF
MOVLW
MOVWF
PORTC
LATC
0CFh
TRISC
; Initialize PORTC by
; clearing output
; data latches
; Alternate method
; to clear output
; data latches
; Value used to
; initialize data
; direction
; Set RC<3:0> as inputs
; RC<5:4> as outputs
; RC<7:6> as inputs
© 2007 Microchip Technology Inc.
Advance Information
DS41303B-page 123