CNC plotter 1800 x 80cm, first build, questions and queries.

[Doddy]

Simplest test first is as Jazz says - check the BOB EN pin and that your e-stop isn't activated. Been there... worn the tee-shirt.

To test the drivers, disconnect the PUL+ wire from the break-out board to each of the drivers one at a time, and with a bit of wire in the PUL+ input to the driver strike that against the +5V supply. Each connection (and each break/make as you make the connection) should turn the respective motor by one step (or microstep). You might get more joy just listening if the drivers are configured with a large number of micro steps. That will give you a basic level of confidence that the drivers and motors are okay. It's hard to predict the terminal voltage of the drivers - depending upon the motor position you're going to see an instantaneous (static) description somewhere along the waveform of a sine-wave across A-/+ and B-/+ each 90 degrees out of phase (so when A is +Big Volts, B would be tending to Little Volts.... but all depends on where the driver thinks it is along it's rotation.

You could also strike +5/0V across the EN+/EN- of each driver. That should free the motor on that axis. Not very useful, but again some confidence in the operation of the driver.

If you get that far then your issues lie either in the break-out board, or your Mach3 installation.

It worries me that you say that none of the LED outputs are illuminated - if you jog one axis in one direction, then the other, at least one of the LEDs for the DIR outputs to the drivers should be illuminated in one jog direction. Failure of this would be an indication that there's a problem or misconfiguration of the BoB. Or the EN input. Or the connection to the PC.