spindle speed configuration question

Hi all,

I just moved to a spindle after years of using LinuxCNC with a trim router.

Everything seems fairly straighforward, but.....

I'm trying to get PWM to work with my breakout board and .... well...

I set up the basic config, as per the documentation.

speed 1 is 0, PWM 1 is 0
speed 2 is 1000, PWM 2 is 1

If I'm understanding this correctly, this should allow me to go up in speed (S100, S200.... S800, S900) and basically change the analog voltage at my breakout board from 0-10V (My breakout board goes from 0-10V).

And it does... sorta...

It goes backwards! S500 is 5V. S200 is 8V, S800 is 2V. WHY?

Try inverting the PWM pin. Maybe the BoB expects active-low?

That totally worked. No idea WHY, since this is supposed to be a PWM wave and it really shouldn't matter, but... fuck it, it works.

Thanks!

PWM is inverted if the pin polarity is changed.

100% is either constant 5V or 0V, and then 0% is, respectively, 0V or 5V.

At 50% it doesn't matter

this is for 5axis China mach boards they are activ low designed
and also expect that on the Step dir inputs