Mechanical keyboard

 A little while back I built a mechanical keyboard (3D printed Redox mechanical keyboard) with a Pi pico and programmed it with KMK (Setting up KMK on a Pi Pico mechanical keyboard).

I'm going to start adding extra information here that I missed from the videos, the first thing is a bit of a wiring schematic:

Rows schematic

At about 3:44 in the build video I start wiring the rows, the above is a schematic of what I was doing. Each key has a diode to allow multiple keys to be pressed. As the legs were long I could use my diodes  as the connectors.

Column schematic

The wires for the left half were thread through some para-cord and taken to the right half, the rows were joined as if it were a single piece keyboard - this is not the best way to do things but was very practical for a first go :)

The end result is 5 rows and 14 columns each with the same number of keys. I used different colour wire to help with trouble shooting and connected rows and columns to different sides of the pico. It was easier for me to check everything by writing a quick python script to confirm a key press but that's because I didn't realise how easy KMK would be to set up.

Future:

• Matching track ball with pan/tilt and zoom for CAD work. A pico should be able to do this. I'm inspired by this one: https://hackaday.com/2021/11/21/a-trackball-so-good-you-cant-buy-it/ I built a bit of a HID many years ago here: https://www.instructables.com/Two-dimensional-Vectrometer/ it looked quite scruffy but worked really well and survived being dropped more times than most devices would.
• Card readers and ports: I always seem to need an extra USB port or the other size SD card reader. A future keyboard or macro pad will just have them built in.