ZMK Raytac USB Dongle Module

This repository adds a ZMK board definition named raytac_mdbt50q_rx for the Raytac MDBT50Q-RX USB stick, with the intention of using it as a ZMK keyboard dongle.

Caveat: Buy One With A UF2 Bootloader Installed

The stock MDBT50Q-RX does not come with the UF2 bootloader installed—that's the bit of code that allows it to mount itself as a USB drive for flashing.

But! Some versions of the dongle do exist with the UF2 bootloader pre-installed, and that's what you want buy: Adafruit (USA) and Pi Hut (UK) sell them, and probably others if you search around. I used the one from Adafruit.

Maybe You Should Update The Bootloader Too?

I upgraded the version of the bootloader on my Raytac dongle. I don't know if this is necessary because I upgraded before flashing ZMK onto it. It was easy and didn't hurt anything?

I used these instructions to update the bootloader to version 0.9.2. Specifically I used this exact one.

Usage

Add the following entries to remotes and projects in config/west.yml

manifest:
  remotes:
    - name: zmkfirmware
      url-base: https://github.com/zmkfirmware
    - name: rschenk
      url-base: https://github.com/rschenk
  projects:
    - name: zmk
      remote: zmkfirmware
      import: app/west.yml
    - name: zmk-component-raytac-dongle
      remote: rschenk
      revision: main
  self:
    path: config

Configuring Your Dongle

Follow the setup steps in the ZMK Keyboard Dongle docs to configure your keyboard and dongle. When you get to the Building the Firmware step, you will use board: raytac_mdbt50q_rx in your build.yml file like so:

include:
  # Config settings for the dongle
  - board: raytac_mdbt50q_rx
    shield: my_keyboard_dongle
    
  - board: raytac_mdbt50q_rx
    shield: settings_reset

  # Whatever your keyboard uses...
  - board: nice_nano_v2
    shield: my_keyboard

Flashing The Raytac

Entering the bootloader mode is a bit annoying. Unplug the dongle, then hold the button down while plugging it back in.

For some reason you can't double-click the reset button like on many boards.