I'm no expert on these so I thought I'd come here and ask.
I have a HobbyCNC Foam Cutter board Rev 1.
One stepper motor on my foam cutter, has failed and another works
intermittently. Something on the board has gone as I can swap the steppers to a different output and they work fine.
What would my next steps be to Investigate or repair?
It's not the computer, stepper motors or parallel cable as they all work fine.
have you contacted Hobbycnc ?
they should be able to help you with fault finding
I've don't know any thing about your board
but the hobbycnc pro board for instance
has a circuit that detects the step signals
this circuit switches the reference voltage to the SLA7078
from a level that disables the motor drive (>2V) when its not receiving step pulses
down to a lower voltage that sets the motor current when the motor is being stepped
(this circuit is based on the IC manufacturers data )
it could be useful to download the data for the IC's
used on your board
then look for any difference in the voltages needed
to enable the driver IC's