Microchip Technology MCP1631RD-MCC2 Data Sheet

 2006-2012 Microchip Technology Inc.

DS41291G-page 55

PIC16F882/883/884/886/887

3.5

PORTC and TRISC Registers

PORTC is a 8-bit wide, bidirectional port. The
corresponding data direction register is TRISC
(

). Setting a TRISC bit (= 1) will make the

corresponding PORTC pin an input (i.e., put the
corresponding output driver in a High-Impedance mode).
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).

Example 3-4

shows how to initialize PORTC.

Reading the PORTC register (

) reads the

status of the pins, whereas writing to it will write to the
PORT latch. All write operations are read-modify-write
operations. Therefore, a write to a port implies that the
port pins are read, this value is modified and then written
to the PORT data latch.

The TRISC register (

) controls the PORTC

pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISC register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’.

EXAMPLE 3-4:

INITIALIZING PORTC

BANKSEL PORTC

;

CLRF

PORTC

;Init PORTC

BANKSEL TRISC

;

MOVLW

B‘00001100’ ;Set RC<3:2> as inputs

MOVWF

TRISC

;and set RC<7:4,1:0>
;as outputs

REGISTER 3-9:

PORTC: PORTC REGISTER

R/W-x

RC7

RC6

RC5

RC4

RC3

RC2

RC1

RC0

bit 7

bit 0

Legend:
R = Readable bit

W = Writable bit

U = Unimplemented bit, read as ‘0’

-n = Value at POR

‘1’ = Bit is set

‘0’ = Bit is cleared

x = Bit is unknown

bit 7-0

RC<7:0>: PORTC General Purpose I/O Pin bit
1 = Port pin is > V

0 = Port pin is < V

REGISTER 3-10:

TRISC: PORTC TRI-STATE REGISTER

R/W-1

(1)

R/W-1

(1)

TRISC7

TRISC6

TRISC5

TRISC4

TRISC3

TRISC2

TRISC1

TRISC0