[ny_racer_xxx]

We need more information. What breakout board are you feeding the UC100 into? And, what PWM base frequency for the spindle speed signal does the breakout board require?

Cheers
Peter


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I'm pretty sure that's irrelevant, it works with the PC parallel port setup, it doesn't the USB UC100 port... There must be something more to the UC100 setup, or it's not actually running 100Khz.

I did get the win7 PC running again and verified with the parallel port, the spindle speed is good, so it's not a hardware issue.

[ny_racer_xxx]

Peter, it's also not using PWM, it's setup like another stepper.
Mach3 Motor Tune
Steps 2000, Velocity 2500, Acceleration 25