Gpio not turning high in led blink program

Thread Starter

sreejith.arikath

Joined Jan 19, 2022
1
Hi all iam new to pic12f675.trying to implement led blink program
But Gpio not turning high
kindly review the code below and please guide

MOD: Please use Code Tags.

C:
#pragma config FOSC = INTRCIO // Oscillator Selection bits (INTOSC oscillator: I/O function on GP4/OSC2/CLKOUT pin, I/O function on GP5/OSC1/CLKIN)

#pragma config WDTE = OFF // Watchdog Timer Enable bit (WDT disabled)

#pragma config PWRTE = OFF // Power-Up Timer Enable bit (PWRT disabled)

#pragma config MCLRE = ON // GP3/MCLR pin function select (GP3/MCLR pin function is digital I/O, MCLR internally tied to VDD)

#pragma config BOREN = OFF // Brown-out Detect Enable bit (BOD disabled)

#pragma config CP = OFF // Code Protection bit (Program Memory code protection is disabled)

#pragma config CPD = OFF // Data Code Protection bit (Data memory code protection is disabled)


#include <xc.h>

#define _XTAL_FREQ 4000000

void main(void) {

TRISIO = 0x00;//set led as o/p

ANSEL = 0x00;//for setting digital i/o

CMCON = 0x07;

VRCON = 0x00;

ADCON0 = 0x00;

GPIO = 0;

// INTCON.PIE=0;

while(1)

{


GP2 = 1;// setting port as 1

__delay_ms(2000);

GP2 = 1;// setting port as 1

__delay_ms(2000);
return;
}

}
 
Last edited by a moderator:

AlbertHall

Joined Jun 4, 2014
11,954
GP2 is a totem pole output so it should work.
Remove the 'return' in the while loop - 'main' in embedded programs should not return. I don't know what it would do if it does hit a return.
 

LesJones

Joined Jan 8, 2017
3,701
I am VERY poor at "C" programming but it looks to me that GP2 is only set high. Either line 41 or line 45 should be changed
to GP2 = 0;// setting port as 0
Show us how the LED is connected to GP2. Is the end not connected to GP2 connected to 0 volts or +5 volts. Is it the anode or cathode that is connected to GP2. (NOTE there should be a current limiting resistor in series with the LED.)
Note It is GP3 (Pin 4) that is open collector.
Les.
 
Top