Making with the micro:bit

(I finally regained access to my blog after a hiatus of almost a year!)

On Friday I was invited to present at one of a week-long series of events hosted as a part of the SERAS Environment Making Challenge where I was introducing people to the BBC micro:bit and showing a little of what could be done with it. If you came along, thanks – it was great to ‘see’ so many of you on a stifling hot Friday afternoon! I hope you enjoyed the session.

As this was a virtual event I wanted people to get a feel of how we’d do this sort of thing if we weren’t all locked down in our own separate bubbles. Even if you missed it, you can still take a look below where I cover the quick demo project I showed in the presentation.

So – here it is! I know this is an environmental challenge but I wanted to show something quickly that was good visual / audible demo, so working micro:bit ukulele it was! (although I showed it to my 10yr old nephew who commented, ‘you realise it’s actually a piano’ – no dust on that one)

I didn’t really have time during the session to dive into how this was put together, so if you want to have a go at creating it, here you go….

BUILD IT

You’ll need…..

  • A micro:bit & USB cable (battery pack optional)
  • A micro:bit expansion board
  • Alligator clips (1 per note + 1 for GND + 2 for speaker / headphones)
  • M/F Jumper wires (aka DuPont cables)
  • Speaker / headphones
  • Cardboard
  • Gluestick
  • Tin foil
  • Pencil / Ruler
  • Sellotape

I actually used a ukulele we have here – which is kind of cheating but you can make it any shape you want.

_1030206

 

Cut out some foil strips, measure even spaces along the neck of your ukulele..

_1030208

 

Stick them down using the glue sticks. When you’ve stuck them down, cover the back of the neck with another piece of cardboard and glue / tape this in place. This is to stop your thumb touching the back part of the neck where the foil strip are.

_1030210

 

Add another circle of foil to the body of the ukulele, this is where your ‘ground’ finger goes (I use index finger on my right hand) and then attach alligator clips to all of the foil pieces as shown below. Then clip M/F jumper cables to the other ends of the alligator cables. Decorate to suit!

_1030215

 

Plug the micro:bit into the expansion board (the buttons should be facing up).

The cable from the CIRCLE foil goes to 0v (Zero volts)

In this example, the other four cables go to pins 1, 3, 4 and 10.

1A7FC7F1-A368-4849-98B1-8FDEEA5A003C

 

The final two cables are for the speaker (or headphones.) These attach to pin 0 and to ov (zero volts)

BD92D013-C730-4F49-B91F-C334BD41B4D8

 

The other end attaches to the speaker plug like this.

E56E5B6A-5055-4ABC-9EEE-F3A31FF0F4D0

 

Your micro:uke is now ready to add some code and play!

You play it by holding one finger on the circle foil with your right hand, and then use your fingers from your left hand to touch the foil strips.

_1030218

 

CODE IT

The following code was made using the Make:code editor

Using the pins via the expansion board can interfere with the functioning of the LEDs so we turn them off to start with.

Screenshot 2020-06-27 at 18.20.44

 

The following code then plays the right note when one of the strips is pressed…

Screenshot 2020-06-27 at 18.20.35

You’ll need to make sure you get the wires / pins / notes in the right order so you’re micro:uke plays properly! You can also add more cables to make more notes.

You can also code this in Scratch which gives you a wider range of sounds that you can play with the instrument.

Thanks to everyone again – hope you enjoyed this make!

Until next time…..

Leave a Reply

Your email address will not be published. Required fields are marked *