Raspberry PI - Program a Blinking LED

1. Connect your LED's cathode (short leg) to a 0V or Ground pin of the Raspberry PI. 
2. Again connect your LED's Anode (Long Leg) to a GPIO pin via a resistor around 150 ohms (Resistor will save your LED from burnings due to high voltages). Here we use GPIO 8 to be connected to the Anode.
3. Write the following code.


#include <wiringPi.h> //import the wiringPi lib
#include <stdio.h>


#define LedPin 8  //GPIO index which will be connected to the LED's Anode


int main(void) {
//Initializing the wiringPi
       if(wiringPiSetup() == -1) {
               printf("setup wiringPi failed !\n");
               return -1;
       }
                                
                                //Set the PIN mode as output

       pinMode(LedPin, OUTPUT);


       while(1) {
               digitalWrite(LedPin, LOW);   //led on
               printf("led on\n");
               delay(1000);                 // wait 1 sec
               digitalWrite(LedPin, HIGH);  //led off
               printf("led off\n");
               delay(1000);                 // wait 1 sec
       }
       return 0;


}




Save above code as blinking_led.c then compile and run as below.

• gcc blinking_led.c -o blinking_led -lwiringPi
• ./blinking_led