23 November 2025

Finally got the PCBs from the manufacturer: five of them are empty, and one is complete, with all the components soldered.
I ran a simple electrical test before applying power, and everything looked fine. Then I connected the board to a USB power source, and there were no issues.
Quick and dirty test firmware has been complied using QMK and it worked!

I still need to order a second board to make it look pretty, but for the test, I connected the wires directly to J2, connected the board to Rabbit, and played Mortal Kombat: Unchained for a good half hour.

Couple things that made me nervous: 

1. My power meter tool was unable to detect any current draw when I hooked PCB to power source. Seems like un-flashed rp2040 does not really drawing anything.

2. Firmware was unable to detect buttons being pressed until I edited code and changed diode direction to 

COL2ROW even though I don't have diodes at all: every button is connected to it's own GPIO to prevent ghosting.