Firmware to test Planck PCB Keyboard Matrix
This firmware has a single layer and each key position runs a macro that outputs the matrix location of that key. Row Col. r0c0 is the top left position. r3cb is the bottom right key.keymap.c
planck_rev4_test.hex
You will want the default firmware to reload after testing is done.
https://github.com/jackhumbert/qmk_firmware/tree/master/keyboards/planck
Example output in a text editor:
