The dulcimer project is a USB replacement controller for the IBM Model M keyboard.
You can find the original documentation here:
http://www.schatenseite.de/2008/07/12/dulcimer/
The port of the TMK firmware to the dulcimer USB controller for the IBM Model M keyboard can be found on my Github:
https://github.com/nuess0r/tmk_keyboard/tree/master/keyboard/dulcimer
This controller uses an ATmega32 and the VUSB library for USB support as this controller doesn't include a real USB interface.
You can use the original dulcimer hardware without modification with this TMK firmware.
If you don't own one, you can build one yourself. In the circuit sub-folder is a KiCAD project for the dulcimer.
It's a one layer PCB using only through hole components so you can etch your self a PCB.
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