MNT Reform Optical Trackball

Add a Trackball to Your Project.

This is the optical trackball module for the MNT Reform. In addition to precise X/Y tracking of the POM ball, it features five buttons (three mouse buttons and two wheel mode buttons). The keyswitches are Kailh Choc Browns. The controller is an ATmega32u2 with open source firmware that presents the trackball to the system as a USB HID mouse. The USB signals are on a 4-pin JST-PH connector. Includes fitting JST-PH cable to connect to MNT Reform internal UI1 or UI2 header.

As a maker, you can also use this module to easily add a trackball to your own project. The trackball is fully open source hardware.


  • Precise X/Y tracking of the POM ball
  • 5 buttons (3 mouse buttons and 2 wheel mode buttons)
  • Key switches: Kailh Choc Brown
  • Controller: RP2040

In the Box

  • MNT Reform Optical Trackball Module
  • JST-PH cable
  • Manual


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