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Beating heart

Beginner | MakeCode, Python | LED display | Animation, Iteration, Sequence

Step 1: Make it

What is it?

Make your micro:bit’s heart beat using loops to create an animation.

These two videos show you what you'll make and how to code it:


Coding guide

How it works

  • The program shows a beating heart using two built-in pictures, a large and small heart, on the micro:bit's LED display.
  • Different images shown in a sequence create the illusion of movement: a heart getting larger and smaller.
  • After showing each image, the program pauses for half a second (500 milliseconds) before showing the next image.
  • The animation is kept going forever using an infinite loop: it repeats the sequence of showing these two images and pausing until you unplug the micro:bit.
  • Using loops to keep things happening is an important idea in computer programming: we have created an animation that will keep running for as long as the micro:bit has power using only a small amount of code. This is also called iteration.

What you need

  • micro:bit (or MakeCode simulator)
  • MakeCode or Python editor
  • battery pack (optional)

Step 2: Code it

1from microbit import *
3while True:
5    sleep(500)
7    sleep(500)

Step 3: Improve it

  • Make the heart beat faster or slower by changing the delay time.
  • Try animating other built-in images like the small and large diamond or square.
  • Create your own animations using your own designs.