I have become the caretaker of a nifty little MicroProto CNC Mini Mill. I did a lot of work trying to get the original driver unit to work, but alas couldn't get the steppers to do anything but vibrate. First I tried to control the driver with Linux CNC using a Mach 3 configuration that I imported. Then I wrote some code for an Arduino mega. That still didn't work.

So I picked up some new stepper motor drivers, and those worked like a champ.

Ultimately, I ended up replacing the guys of the driver unit with:
- 3 new stepper motor drivers
- 1 Arduino Uno loaded with Grbl
- A screw shield for the Arduino
- A 24 VDC power supply repurposed from an old Ender 3 I had laying around for parts.
- Two 24VDC 40mm fans (one sucking, one blowing - hee hee)
- Ferrules. I love ferrules. Oh my gosh how did I ever get along without ferrules?
- A USB B panel mount jack with extension cable.

I've been controlling the setup with gSender.