A 36-key keyboard

About two years ago I switched to a 36-key keyboard and I have not looked back since. So I thought, why not make my ideal keyboard hardware and software? The keyboard hardware and software are in an early stage but the keyboard is in use as my primary keyboard. Before, I was using a 36-key split bluetooth keyboard that runs ZMK. This new one feels a lot better. Typing feels instant, I don't notice any latency. Probably because I now use a cable and not bluetooth but even compared to other cable keyboards this one feels amazing. Of course, there are a few bugs but they will be fixed soon.

Hardware:

• 2x 18 keys
• 2x rotary encoders
• 2x OLED screens (256x64)
• 2x Raspberry Pi Pico

Software:

• low latency
• different applications (handled by the second core)
  • pin protection
  • LLM client (via API, future on-device?)
  • todo tasks
  • timer for focus
  • settings
  • snake

To Do

Software

• Keys should not reactivate once a mod key is pressed
• OLEDs should be turned off by key combination to avoid burn in
• I need add an option for mod keys that allows keys to be pressed and held until the next key is pressed.

Hardware

• I really need to redo the CAD model since there are some design flaws
• Building the keyboard was painful. So the next change should be a flex PCB

Documentation

MCU: Raspberry Pi Pico

...

Communication

The two halves communicate over UART. Power, GND, and UART are connected over a USB-C cable. I am not using the USB protocol for this. I am splitting the USB lines on both ends and only connecting power, GND, UART RX, and UART TX.

The primary half communicates with a PC over USB (TinyUSB).