MicroFit: Your very own Step Counter

Overview

Ever wondered how a smartwatch or fitness band counts your steps? In this project, you're going to build your very own step counter using a !

Inside your micro:bit is a clever little sensor called an . It can feel when the micro:bit moves. We'll use it to spot every step you take, add them up, and show the total on the (the grid of lights on the front).

The best bit? When you're done, you'll have a real working fitness tracker you can pop on and take outside. Don't worry if something doesn't work first time, that's all part of coding. Let's give it a go!

🎯

What you'll learn

How a light sensor measures the light around it
How to use an if/else block to make a decision
How to switch an RGB LED on and off automatically

What you'll need

The micro:bit MakeCode editor
micro:bit
micro USB cable
battery pack for the micro:bit (optional)

Key words

Variable

A variable is something that can change. Think of it like a labelled box: you pop something inside, and the label tells you what it is. You can swap what's inside whenever you like.

Real-world example: A variable called score might start at 0, then change to 1, 2 and 3 as you collect points in a game.

Accelerometer

An accelerometer is a tiny part inside the micro:bit that senses movement, like tilting, shaking or being turned over. It turns that movement into numbers your code can react to.

Real-world example: A bit like the sensor in a games controller that knows when you tilt it to steer, the accelerometer notices when the micro:bit moves.

LED Matrix

The LED matrix is the grid of little red lights on the front of the micro:bit. By switching them on and off in patterns, your code can show numbers, letters and tiny pictures.

Real-world example: Like a mini scoreboard made of dots, the LED matrix lights up to spell out your step count.

Forever loop

A forever loop repeats its instructions again and again without ever stopping (until you switch off or reset). It's perfect for anything you want to keep happening over and over.

Real-world example: Like a clock's second hand that keeps ticking round and round, a forever loop keeps running the same steps over and over.

Button

A button is a switch you press to tell your project to do something. The code can check whether it's being pressed or not.

Real-world example: Pressing a doorbell is just like pressing a button, one press sends a signal that makes something happen.

Navigating to the MakeCode Editor

On a Computer

Open your favourite web browser. We recommend either Google Chrome or Microsoft Edge.
In the Address bar type makecode.microbit.org.
Select New Project and give it the name MicroFit.

The MakeCode code area

On a Tablet or Phone

Open the micro:bit app. If you don't have the app yet you can download it from your devices app store by searching for micro:bit.
Select Create Code.
Select New Project and name it MicroFit.

Set up the Code Area

Select the on start block and drop it on the bin icon to delete it.
Select Input. Select a on shake block and drop it within the code area.
Select Input. Select a on button A pressed block and drop it within the code area.

Setting up the code area

Change Steps by 1

Select Variables, choose Make a Variable, and name it steps.
Snap a change steps by 1 block inside the on shake block.

Every time the micro:bit detects a shake, it adds one to your steps .

Adding change steps by 1

Show the number of steps

Select Basic, then snap a show number block inside the forever block.
Select Variables, then snap a steps block onto the show number block, where it says 0.

This keeps running and shows your step count on the

Showing the number of steps

Reset the steps to zero

Select Variables, then snap a set steps to 0 block inside the on button A pressed block.

Now, pressing A on the micro:bit resets your step back to zero.

Setting steps to zero

Downloading Your Code

Using a Computer

Select the three dots next to Download.
Select Connect Device.
A pop-up will show you how to connect the micro:bit to the computer. Keep following the on-screen instructions.
Select BBC micro:bit XXX and select Connect. The XXX is your own micro:bit's name, so don't worry if it looks a little different.
Select Download.

Downloading your code

Using a tablet or phone

Select Download.
Follow the on-screen instructions to pair the micro:bit with the micro:bit app.

Once you've finished the on-screen steps, your code downloads to your micro:bit.

Run it and Watch

Shake the micro:bit to watch your steps go up. Pop a battery pack on, attach the micro:bit to your wrist or ankle, and head outside to see how many steps you can rack up!

Dont Have a microbit We can test it on the MakeCode editor by selecting the white dot next to shake on the micro:bit simulator and watch our steps counter climb everytime we select the dot.

Shake button on the micro:bit Simulator

Try it yourself

Challenge: Set yourself a step goal! Add an if block inside the forever loop to check when steps reaches a target, like 20. When you hit it, make the micro:bit show a happy face or play a sound to celebrate, then press button A to reset and go again.

Stuck? Quick fixes

Problem	Try this
The number doesn't go up when I shake it	Check your `change steps by 1` block is inside the `on shake` block. Give the micro:bit one firm, clear shake.
The count jumps up by lots at once	A big wobble can look like several shakes. Try one single, definite shake each time.
Nothing shows on the LED matrix	Make sure the `steps` variable is snapped inside the `show number` block, and that `show number` is inside the `forever` block.
The number doesn't change straight away when I shake fast	That's okay, it's still counting! The micro:bit can't show the new number while the last one is still scrolling. Stop shaking for a moment and your latest total will pop up.
Button A won't reset the steps	Check the `set steps to 0` block is inside the `on button A pressed` block.
My code won't download to the micro:bit	Use a data USB cable (not a charge-only one), make sure the micro:bit is paired, and try a different USB port.