BBC micro:bit – Voting System

In this challenge you will create a voting system using the BBC micro:bit. You can complete the code online on the BBC micro:bit website.

The idea is to use the BBC micro:bit in the classroom to conduct a survey by asking a yes/no question such as:

• Should our school change our school uniform?
• Should we have more computer science lessons on our timetable?
• Should we have more healthy eating options on our school menu?

Then you will pass the micro:bit around so that each pupil can vote using the A and B buttons of the microbit:

• A: Vote Yes
• B: Vote No

Using two variables called voteA and voteB the BBC micro:bit will keep track how many times the A button is pressed and how many times the B button is pressed.

After each vote the BBC micro:bit will display a tick for two seconds to confirm the vote.

To finish the vote the user will press both A and B buttons at the same time. In this case the BBC micro:bit will display how many A votes have been recorded (variable voteA), how many B votes have been recorded (variable voteB) and then use an If Statement to decide if option A (Yes) Or B (No) wins. To do so it will use comparison operators such as > or <. (if voteA > voteB then A wins)

Building the voting system step by step:

Step 1: Initialising the BBC micro:bit

Let’s initialise our voteA and voteB variables that will be used to count how many tumes the A nad B buttons have been pressed.

Step 2: When button A is pressed

When button A is pressed we need to increment A by 1. Then we can display a tick to confirm the vote was recorded.

We then display a question mark to inform the user the BBC micro:bit is ready to accept another vote.

Step 3: When button B is pressed

Very similar to the previous code, this time to record the B vote.

Step 4: When A+B are pressed simultaneously

The user pressed both A and B at the same time to end the vote. In this case the BBC micro:bit will display how many A votes were recorded, how many B votes were recorded and decide if A or B wins or if it is a draw.

Complete and Test your Voting System

Test the game using the online emulator. Then when you are confident if fully works, download your code to the BBC micro:bit and conduct your first survey with your classmates. Make sure you ask for a question with only two possible answers (e.g. Yes/No question).