Control a Raspberry Pi GPIO with Python

28 March 2021

Circuit Diagram

This script will make use of the GPIO Pins to flicker an LED

The circuit diagram is below:

I've used a $330\Omega$ resistor for the resistor connected in series $R_LED$, however the resistance for a given LED can be calculated with this equation (From Circuit Specialists):

$R_{LED} = \frac{V_{source} - V_{LED}}{I_{LED}}$

It's important to connect the LED in the correct direction on the circuit

Code

Below is a simple python script which will handle turning the GPIO pins on and off using the RPi.GPIO library

import RPi.GPIO as GPIO
import time

pin = 21
dur = 1

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(pin, GPIO.OUT)

while True:
  GPIO.output(pin, GPIO.HIGH)
  print "LED ON"
  time.sleep(dur)

  GPIO.output(pin, GPIO.LOW)
  print "LED OFF"
  time.sleep(dur)