When doing investigation on keypads/keyboards I realized all implementations are wired in matrix forms (columns and rows). This is a 2D approach, but we can take it a step further and use 3 dimensions (or more). This can give us more keys with the same amount of pins, depending on the number of keys…

Wiring keypad in cube instead of matrix

anon57585045 September 22, 2021, 8:53pm 4

Sure, you can Charlieplex a keyboard too. No gates or transistors, just diodes.

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