OpenEx is an open-source QMK-powered trackball by u/Skribbles4420 – inspired by the Kensington Expert.
KBD.news Published June 24, 2022
Not a keyboard but maybe another useful companion: OpenEx is an open-source trackball designed by Skribbles4420.
OpenEx was an idea that came to me while searching around for various types of trackballs one evening. I saw of course the Kensington Expert and was immediately inspired to create a trackball device that was emulative of what I had discovered.
The wiring for all the switches and other components to the microcontroller is all done by hand but in the next revision the author plans on designing the PCB with the sensor circuit integrated as well.
The sensor that is currently being used is that of BastardKb (pmw3360):