controller and motors not fully communicating

HiI got a small DIY milling machine from a friend who bought it from some guy a couple of years ago. When I plug everything in, Linux opens up, and I can jog the axis on the screen, the ini folder looks like it's set up, the controller turns on, but the motors don't jog even though they get warm. I'm wondering if there's some communication issue and where to start. I have run a foam cutter with Linux and know the tiniest bit about this, but not sure where to start diagnosingHelp is appreciatedThanks  



 

I would do some simple electrical checks
like seeing if the direction signals going to
the step drives change from 0 to 5V
(or vice-versa) when you jog in opposite
directions.

sorry for not replying sooner. usually I get an email when a reply comes in. i also have not had time to tinker but i will check that out

Hi
I know it's been months since I did my last post but i've been fiddling with this thing in my spare time. just to clarify, I have a Probotix box with motors, which I plugged into the computer running the mill and I could jog those motors. when I checked the voltages to the motors on the control box thats not working, I found the red and black have 22ish, the white and gray have the same but when I jog it doesn't change. What brings that signal to the driver. Thanks

I apologize for being so naive, but where would I find these chips

  In this box? 

the Probotix controller works well, it's the other one (The first pictures) that does not work. the wires coming to the motors are getting power but the voltage does not change when I try to jog. I'm wondering if whatever wires bring the move signal are not doing their job. Originally I thought maybe it was a programming error, but if the Probotix box works...