I recently replaced my Xylotex 4 axis card with a G540. Everything has gone pretty well, except for the stupid spindle control. Which is ironic, as I blew up a C41 trying to get spindle control with the Xylotex. I have everything else working, X, Y, Z home switches, and a touch probe. I referenced PMinMO's drawing, which correlates to the manual as far as G540 pins, but still no spindle movement. I have tried downloading Gecko's XML file to see if I can get it working but no love so far. I have been very underwhelmed with Gecko's tech support, "We don't use MACH so we don't know." The main reason I bought the G540 is because they seem very interested in the hobby side of this also.

My spindle works fine with the stock potentiometer, but I do have an Icon MC-60 controller, replaced because I blew the OEM up with a C6 board...

At one point when I would start MACH3 the spindle would go full on when connected to the G540, but you couldn't stop it or change speed, but now it won't do that.

Are there any troubleshooting tips for the G540 itself? Since it's PWM I don't know if I could measure anything across pin 7 / 8, I don't have an o-scope.

I have checked everything I could find here at the zone, but the dang thing won't budge....

Thanks,
Rod