Using external input and outputs with physical computing devices can be intimidating for learners new to working with micro controllers. There are many add on boards available which can simplify the process, however class sets of these can be expensive. Therefore I wanted to design a very cheap and easy to make board that could scaffold the introduction of external inputs and outputs. My completed design works with the BBC micro:bit and features 3 LEDs, 3 switches, a button and a speaker, copper slug barrier tape is used to connect the components.

Resources Required:

  • Copper slug barrier tape
  • 3mm Red, Yellow and Green LEDs – example
  • 2.7mm piezo speakers – example
  • Paper fasteners
  • A4 card

Follow these steps to create your own boards:

  • Print this input-output board template onto A4 card and cut in half.
  • Cover the light gray areas with copper slug barrier tape (you may need to cut the tape in half to get the correct width).
  • Make a hole in the middle of each switch circle with a paper fastener. Insert a paper fastener into each hole from underneath and open out. Ensure they make good contact with the copper tape, but will still easily pass over it.
  • Open out another paper fastener and use a small piece of copper tape to secure the short side of the paper fastener in place to form the button as shown in the picture.
  • Secure a 2.7cm piezo speaker in place with a sticky fixer. Connect the end of the wires in place with small pieces of copper tape, ensure the red wire goes to the right and the black wire goes to the left.
  • Bend the legs on the 3 LEDs outwards, lay them flat as shown in the picture and secure each leg in place with a small piece of copper tape. Ensure you place the LEDs the right way around, if one leg is longer it should point right and the flat side of LED should face left.

I’ve put together these example activities to demonstrate how the boards can be used in the classroom. The code for the starter program can be found here.