Step 1: Make it
What is it?
Code your own electronic metronome that makes regular beats which you can slow down and speed up as you practice music.
What you'll learn
- How to adjust the tempo of musical notes played by the micro:bit
- How to use input buttons and audio outputs to make a useful electronic device
How it works
- At the start of the program, it sets the tempo to 100 bpm - beats per minute. This is a standard way of measuring the tempo, or speed, of music.
- A forever loop keeps the micro:bit playing a short note and then resting for one beat.
- You can hear the sound by attaching headphones to pin 0 and GND or on the built-in speaker of the new micro:bit.
- Press button A to slow down the tempo by 5 bpm.
- Press button B to speed it up by 5 bpm.
- Pressing button A and B together shows the current tempo on the LED display output.
What you need
- A micro:bit
- MakeCode or Python editor
- battery pack (optional)
Step 2: Code it
Step 3: Improve it
- You may notice that it plays its rhythm slightly slower than an electronic instrument with the same BPM setting - this is because each loop takes one and one sixteenth of a beat, instead of just one beat.
- You could try and make it more accurate by adding up fractions of a beat to make one whole beat: 1/2 + 1/4 + 1/8 + 1/16 makes 15/16 to add on the 1/16th of a beat that you’re playing the tone for.
- 'Forever' blocks also add a bit of a delay, so using a ‘while true’ loop inside it will speed up your code and make it more accurate.
- The code video at the top of this page shows you how to do this.