screening / glitchy operation - sanity check

[dsc]

I've connected the screen (one end, the other is tied back) for the PUL / DIR inputs into the E(arth) on the PSU, not much difference though, here's a shot before the screen got connected:



and here's after:



Minimal difference, although there's a lot of noise on that line (that's the PUL- / GND scopped). Not sure what it is, or how to get rid of it. On the other hand, the proto board is a mess full of breadboard wires, so isn't exactly super noise resistant.

I can't capture a long scope, I can only do a print screen kind of capture which isn't good enough to show how the PWM frequency changes. I can see a rolling effect ie. frequency increasing on the scope when the motor starts, but I don't know what causes the glitches on the motor. It stopped again with a positioning error today, don't know why though.

EDIT: here's a video, although it's hard to hear the glitches:

Regards,
dsc.