It's not playing ball unfortunately.

I believe I have replicated the circuit correctly, and the X axis does step once when I connect the wire from the base leg to pin 2 on the BOB, but jogging the X axis has no impact. I have also moved the wire from Pin 2 to 3 on the BOB, with no affect. Pin 2 is the X axis step and 3 the X axis direction.

The mill does have just shy of 24V on the signal input. On the picture of the breadboard touching 'X step' to 'Mill GND' causes one step.

How can I test if Mach 3 is making any impact on the BOB? I think all the results I have currently achieved could be been done with just the 5V and GND. I only have a multimeter for testing.

Also I don't think the BOB is capable of switching 24V. Aside from it being very cheap, I think the IC's in the middle handle the output switching (the 5 on the left are opto isolators) Searching 74HC245D found they are 'Octal bus transceiver's capable of handling 2 - 6v. Again way outside my electrical understanding, but I think that's correct.

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ID:	26342