https://www.hackster.io/binsun148/digital-3d-printer-filament-counter-using-ps-2-mouse-2df0da
Digital 3D Printer Filament Counter Using PS/2 Mouse - Hackster.io
Ever wonder how much filament you actually used for a project or have an old mechanical ball mouse laying around to be recycled?. Find this and other hardware...
3d printer filamentps 2 mousedigitalcounter
https://lkml.org/lkml/1999/2/6/9
LKML: Linux Kernel list: ps/2 mouse hangup on 2.2.1
ps 2 mouselinux kernellkmllisthangup