How to find the matrix layout of an old EEPC keyboard

Question

The title asks my question; how can I find the matrix layout of an old EEPC keyboard. I found an instructables about making a USB keyboard controller but it uses a Teensy microcontroller, and I think they are a bit too expensive. So I wanted to use a Raspberry Pi Pico. The instructables gives me an Arduino sketch that can decide the matrix. But the code doesn’t wanna compile with a Pico. So how can I either change the code to work with the Pico or find out how the matrix is made, with for example a datasheet?

Btw: sorry for bad english

Answer 1

You can always look at the matrix wiring if you can open the keybord and see where each wire goes.

Or measure with a multimeter which two pins are shorted when you press some button.

We also don't see why your code does not compile on your platform so we don't know how to change it. Scanning a matrix is just simply setting and reading IO pins so all you need to do is to set IO pins and read them, which every platform supports. You only need to know how to set and read IO pin to scan your matrix.