I was wondering if anyone in the community (or the SparkFun engineers) are in the process if (or have thought about) creating a mechanical keyboard PCB that uses the MicroMod STM32 processor board.
I’m a huge fan of custom mechanical keyboards and after building a few am now at the evolutionary step of creating my own PCB and thought - I wonder if a MicroMod would work here? Turns out someone had thought about this back in 2000 - A bit of research lead me to the M60 PCB ( https://makerdiary.com/pages/m60-mechanical-keyboard ), but deeper dive shows that this is not compatible with SparkFun’s implementation.
I’m keen to explore this as a viable project to undertake, starting with a standardized 60% form factor, a.k.a. GH60 - LadyAda for example sells a plethora of keyboard stuff, cases, plates, switches, caps … all but not a PCB.
I would hate to spend months on prototyping something only to have something out there already done, just not easily findable yet.
We have no plans for such; create away!
Hey @vinorodrigues , we’re trying to do a similar thing with tscircuit and really appreciate your work on this!!! We also plan on using the RP2040 and configuring with QMK. Thanks for the work!!!
I’m curious how you get around the GPIO limitation, I think MicroMod only exposes like 12 right? But is this enough for a standard keyboard?
@TS-Russell awesome!!! Ok will definitely set up a keyboard with it then. I currently have one set up with the Pico so I think it should be easy to adapt to MicroMod.
IIUC the getting started guide basically says you have 12 ~guaranteed GPIO, but then you should start using other pins.
I’m setting up a MicroMod schematic for tscircuit, and I was thinking of allowing the user to be able to specify variant=“RP2040” to allow “better pin labels” for specific modules. Curious if there is any guidance on using GP pins greater than 12.
For “Default 60%” keyboards typically 16 GPIO will be needed, and for a full keyboard with numpad typically 21 GPIO would be needed (for a standard grid-based keyscan!)
Ideally when people build a MicroMod keyboard it’s compatible with as many modules as possible.
You’d just not use the other unneeded interfaces (i2c, SPI, PWM, etc) and map the GPIO as whatever you do need in your code to free up the extras
The first link I sent should illustrate that a bit (for example, simply not using the 2 SPI buses frees up 10+)
