Hi, Yes, the J4 driver hardware (DM320T stepper driver) was/is the problem. The Enabled state is reversed. To test if yours is this way simply remove the wire from Enabled and see if it works. Note that with it removed the emergency stop won't work because it won't stop that motor. I'd be interested to hear if this fixes the problem for you. Mark

Thanks, Joseph! Excellent job with a graphic explanation. Looking forward to part 2!

Hi, thanks. We hooked up an oscilloscope earlier today and believe we have tracked down the problem to two of the stepper drivers. The Teensy seems fine. Mark

Thanks. Yeah we hooked up an oscilloscope to check things out. Everything coming out of the Teensy is fine. And 4 of the motors are working fine, as are the encoders and limit switches. Two of the stepper drivers are not showing reliable output on the scope. The signal in is fine - the signal out is not. I think we had one poorly soldered cable that caused the problems. And we swapped things around as we were testing. So I believe we fried two of them. I've ordered two new drivers which I'll get Friday and will swap them in by Saturday. Using those motors with other drivers we already have has proven to work so I'm hopeful this should fix everything. Mark

Hi Emil, The J4 driver is different from the others. But I did set the DIP switches on one to match J4 and tried it. The J4 motor did move. Maybe that motor driver is messed up. Mark