The_Official_Raspberry_Pi_-_Beginner’s_Book_Vol1,_2018 (1)

Chapter 6 Physical computing with Scratch and Python 137

THE OFFICIAL RASPBERRY PI BEGINNER’S GUIDE

Your finished program should look like this:

from gpiozero import LED

from time import sleep

from gpiozero import Button

button = Button( 2 )

led = LED( 25 )

button.wait_for_press()

led.on()

sleep( 3 )

led.off()

Click the Run button, then press the push-button switch: the LED will come on for three
seconds, then turn off again and the program will exit. Congratulations: you can control an LED
using a button input in Python!

CHALLENGE: ADD A LOOP

How would you add a loop to make the program repeat

instead of exiting after one button press? What would

you need to change to have the LED on while you’re not

pressing the button and off while you are?