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OpenEx trackball

OpenEx is an open-source QMK-powered trackball by u/Skribbles4420 – inspired by the Kensington Expert.
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):

So I downloaded the Gerber files from his GitHub, then had them produced at JLCPCB, then ordered the components for the sensor from mouser and Ali express, then put it all together.

GitHub repo:


The repo, along with other open-source projects, was moved to:

Published on Fri 24th Jun 2022. Featured in KBD #84 (source).

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