I’ve spent the last few months designing a project that runs CircuitPython. Unlike many projects, this project does not use an off-the-shelf CircuitPython development board like Adafruit’s Feather M4 Express or IstyBitsy M4 Express.
Instead, I wanted this project to be a single circuit board that contains all of the functional parts of the project – the CPU and its necessary hardware (which would usually be on the development board) as well as the peripherals (things that would generally be on FeatherWings or shields). This makes the board smaller, more tightly integrated, and eventually easier to produce in larger quantities.
However, creating a custom CircuitPython board isn’t a trivial process. There were quite a few things I ran into that have become lessons for me in the future. This post collects some of those lessons as a reference to myself as well as hopefully a helpful resource for others that are trying to do something like this. It isn’t intended to be a complete guide on how to do this – there’s already a couple of those out there. It’s intended to be a supplementary list of things to look out for.
The post goes into details, design tips and suggestions to avoid pitfalls.
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