well, if you use laptop, you must switch off - power safe - on USB,
but on my try - I found, that this board gets only Gcode as input and calculates everything by itself, sends back to Mach current position - (that is maybe what you describe as - cannot stop it with Mach - the procesor inside gets mad and sends pulses to motor without any request from Mach)
I did try it on 4 diferent PC - XP, Win7, also on laptop ...
I did try different .dll, I did try to contact seller, producer ...
and all the time, there was the same mistake ... so I gave it up. Just angry, how much time I spend with useles experiments
parallel port is not a goog choice !
I use now ethernet smooth stepper (and support board CM126 from Ebay) - to full satisfaction, Now I have stable, exact working machine. Just put it in box, switch it on, configure ... and work.
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