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!”

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