I would like to know where this problem ended up. Did it get resolved and if so how?
Jeff, you were doing a marvelous job of walking him through it. But for the benefit of the rest of the community, it would be good to see how these problems were resolved so the rest of us can learn from it.

I am having a similar problem. I did learn enough from this thread to test my G540 with a battery and check the resulting output in order to see if Mach3/G540 is functioning as designed.

Marty

So, this is where I am with it....the spindle will not turn on when the program starts, but if I start the program, then switch my speed control to manual and start the spindle, then switch it back to program mode the spindle will then turn on with the program for that particular program. Kind of a pain but I gave up working on this...I just deal with it now. Note it does shut off at the end...

Paul