[Andy]’s keypad uses the very affordable Seeeduino Xiao, a tiny board that natively runs Arduino code. Since it has a SAMD21 processor, [Andy] chose to run CircuitPython on it instead.

CircuitPython is a beginner-friendly version of Python designed for microcontrollers. It allows you to write code directly on the device, making it easy to test and iterate on your projects.

Developing in CircuitPython is easy because the entire environment — the code, toolchain, and the devices — are all extremely portable.

CircuitPython is a programming language designed to simplify experimenting and learning to code on low-cost microcontroller boards. With CircuitPython, there are no upfront desktop downloads needed.