As with all projects in the book, the reaction game is designed to build up gradually. The reader is first taken through wiring up a simple circuit with a single LED and a single button, using one to trigger the other. Gradually, the complexity is increased: using the LED to trigger a countdown stopped only when the button is pushed, giving the user a look at how quickly they can react.
The project’s culmination comes with the integration of multiplayer: two buttons are used, and whichever player hits their button first is declared the winner. It’s a simple game, admittedly, but a surprisingly competitive one – and one which introduces a range of core concepts for input handling, timing, and conditional statements.
The MagPi Issue 105 is available at all good supermarkets and newsagents, online with global delivery, or as a Creative Commons-licensed DRM-free no-cost PDF download on the official website.