1 Instructions - Button Matrix
Explains wiring many buttons as rows and columns so fewer Arduino pins are needed, and people point to it for planning or debugging such a grid.
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Explains wiring many buttons as rows and columns so fewer Arduino pins are needed, and people point to it for planning or debugging such a grid.
Suggested as a practical walkthrough for turning a Pro Micro style board into a button box, covering how to wire different inputs with example code available.