This guide will introduce you to the Circuit Playground Express (CPX for short!) and CircuitPython. The Circuit Playground Express is a fantastic little board crammed full of all sorts of sensors, switches and lights. CircuitPython is an open-source derivative of MicroPython, designed specifically for use with Adafruit microcontroller boards like the CPX.

This project will teach you how to use CircuitPython to utilise the CPX capacitive touch pads, Neopixels, slide switch, and onboard speaker. Then you'll combine them to create a rainbow-lit tone piano!

Required parts

This project will utilise the Circuit Playground Express, connected to a computer via a micro USB cable. Alligator clips will be used to connect to the capacitive touch pads, and jumper wires will be used to extend the cables.

And, the finishing touch: key limes! Key limes are smaller than regular limes, and will make excellent piano keys.

The next sections will introduce you to the CPX and to CircuitPython. Let's get started!