Controlling GPIO through web interface in Raspberry Pi - Mini Project: Build & Apply

Controlling GPIO through web interface

📖 Scenario: You have a Raspberry Pi connected to an LED light on GPIO pin 17. You want to control this LED from a simple web page by turning it ON or OFF.

🎯 Goal: Build a small Python web server that shows a web page with two buttons: Turn ON and Turn OFF. When you click these buttons, the LED connected to GPIO pin 17 will turn on or off accordingly.

📋 What You'll Learn

Use the gpiozero library to control the GPIO pin.

Use the Flask web framework to create the web server.

Create a web page with two buttons labeled Turn ON and Turn OFF.

When a button is clicked, the server should turn the LED on or off.

Display the current LED status on the web page.

💡 Why This Matters

🌍 Real World

This project shows how to control physical devices like lights or motors remotely using a web browser, which is useful for home automation or IoT projects.

💼 Career

Understanding how to connect hardware control with web interfaces is valuable for roles in embedded systems, IoT development, and automation engineering.

1

Setup GPIO LED control

Import LED from gpiozero and create an LED object called led connected to GPIO pin 17.

Raspberry Pi

# Import LED and create led object on pin 17
# Your code here

Need a hint?

Use from gpiozero import LED and then led = LED(17).

2

Setup Flask web server

Import Flask and create a Flask app called app.

Raspberry Pi

from gpiozero import LED
led = LED(17)

# Import Flask and create app
# Your code here

Need a hint?

Use from flask import Flask and then app = Flask(__name__).

3

Create routes to control LED

Create two routes in app: /on to turn the LED on using led.on() and /off to turn the LED off using led.off(). Both routes should return a simple string confirming the action.

Raspberry Pi

from gpiozero import LED
led = LED(17)

from flask import Flask
app = Flask(__name__)

# Create /on and /off routes to control LED
# Your code here

Need a hint?

Use @app.route('/on') and @app.route('/off') decorators and call led.on() or led.off() inside the functions.

4

Create main page with buttons and run server

Create a route / that returns an HTML page with two buttons: one linking to /on labeled Turn ON and one linking to /off labeled Turn OFF. Then add the code to run the Flask app with app.run(host='0.0.0.0'). Finally, print the message "Server started".

Raspberry Pi

from gpiozero import LED
led = LED(17)

from flask import Flask
app = Flask(__name__)

@app.route('/on')
def led_on():
    led.on()
    return "LED is ON"

@app.route('/off')
def led_off():
    led.off()
    return "LED is OFF"

# Create / route with buttons and run the app
# Your code here

Need a hint?

Use @app.route('/') to create the main page. Return HTML with two buttons linking to /on and /off. Use app.run(host='0.0.0.0') to start the server and print "Server started".