I only have one and 3 devices that use it. But I'm currently in a project of converting a bunch of my old control panels to be wireless using an arduino esp32-c3 (and s3). I'm trying to get my spinner to use this (just finished with my starwars controller and it works great). If I get this working (need some 10k ohm resistors since then esp32 inputs expect 3.3v vs 5v). I might have an extra one after that. Or better yet, I may have the code that you could just use a $4 board turn your trackball into a bluetooth mouse.