Quote Originally Posted by ptjw7uk View Post
If it is always the same axis I would suspect the lay of the wiring or an earth fault on that axis!

Peter
Thanks Peter but it can't be because of my tests above but.....

Last night I had a light bulb moment all because of one sentence I read why googling for answers...

If the dros in Mach are not changing then Mach is not telling it to move. It sounds like your picking up noise.
I suddenly realised because in my case the dro is changing, it can't be noise on the Motors, or BOB. Mach3 must think it is getting some keyboard input! The spindle is either causing some interference on the wireless keyboard or my HID controller.

Yes, you guessed it, my HID controller is the problem! This morning I went out and tried the spindle without it plugged in and there was NO movement of the Y axis. So now I know what the problem is, I just have to figure out why.

The HID controller is just a very simple single sided home milled PCB...

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I am thinking it's either interference on the USB or my board/wiring. I am guessing the latter and would assume if I disconnect the joysticks and it's the former I would still get movement.

I could maybe fix it in the code by increasing the bounce time on the inputs (currently set to 10ms), but it would be nicely to identify the underlying hardware problem.

At least I have some direction now.

Regards,

Les