[mactec54]

I realize that GCode doesn't recognize the comma. Active High and Active Low changes result in the spindle not coming on at all and wouldn't reverse the analog out signal, only how it is recognized or ignored. I am not using Step/Direction.

Guess I dodged a bullet when I reversed them and put them back, ending up with the same result as before I tried switching them.

G-Code can recognize a comma, that is why it should not be used with the S command

What is the spindle motor you are using as not all can have FWD and Reverse??

Do you have this manual??

The Ports & Pins Outputs for the spindle control can be set to active low, just depends on the configuration, doing this has nothing to do with Step / Dir control

Have you checked all the jumpers on the MB3 Board are in the right position.

[jlmccuan]

Weird!! I had previously changed to all possible configurations for the Active High and Active Low in the motor outputs. Anything but an Active High on Step and Active Low on Direction, and the spindle would not come on. On an "out of ideas hunch" I changed the Direction Pin to an unassigned pin, Pin 1 of Port 3, and it ran but with the voltage reversed. I changed the Direction to Active High and the voltage swapped. Everything is working and, I just have to calibrate my rpm's which is easy. Evidently Mach3 wants to see a pin, used or not, for Step and Direction, even though I'm running PWM through the Analog Out pin on the MB3.

Thanks for all the help, and for those looking for an answer, this might be it for them as well.