so now i added a scale (which is maximum rpm) and i can command various 
speeds but still the motor vibrates. somehow it sounds like it ramps up and 
down a bit when commanding for example 2000rpm. Noise could probably be, i 
may change the output to another port (had some coordinate moves with 
various spindle speeds and when one axis changed direction, the motor 
stopped for a few milliseconds), is there any pin i can use for pwm that 
has 5v output on its own?

what do you mean by "pull-up"?

Am Donnerstag, 22. September 2016 18:05:46 UTC+2 schrieb Charles 
> On 9/22/2016 10:02 AM, Sag ich Dir nich wrote: 
> > 
> > setp       915 
> > setp hpg.pwmgen.00.out.00.enable    1 
> > setp hpg.pwmgen.00.out.00.value     0.0 
> > net spindle-speed-cmd motion.spindle-speed-out-abs => 
> hpg.pwmgen.00.out.00.value 
> > net spindle-on motion.spindle-on => hpg.pwmgen.00.out.00.enable 
> > 
> > but somehow the motor, as i turn the machine on, starts to rotate like 
> it 
> > vibrates (turns on and off like 20-30hz) 
> What are the values on spindle-speed-cmd and spindle-on when this 
> happens?  You can monitor them with halcmd, halmeter, or halscope. 
> > and when i press the spindle cw button at 100%, the motor turns smooth 
> but if i 
> > use spindle override it vibrates, but also spins, more, the more i go to 
> 0% 
> > (even at 0% the motor vibrates at a low frequency) 
> > 
> > m3 and m5 commands as well as spindle speed commands are ignored = no 
> change 
> Note that by default, the pwmgen has a scale of 1.0 (0.0=off, 1.0=on), 
> so you might want to change this to match up better with your motor 
> driver (perhaps 0-100 for percent, or scale for apx. RPM). 
> I doubt that's causing your problem, but it can be confusing 
> sometimes.  I think your issue is either with the commanded values, or 
> the floating motor drive input (below). 
> > i have connected 5v to the extruder power input (P402) but no GND 
> connected on 
> > the terminal because i am using the extruder 0 output for PWM (i know it 
> is for 
> > 12-24v but the motor controller works with 5v) 
> The FET outputs will happily switch any voltage lower than 12V (for 
> the low-power outputs) or 24V (for the high-power outputs).  You can 
> switch 5V (or even 3.3V) just fine. 
> Note when the output is switched off, it is essentially floating (the 
> FET is turned off, and there is no low-impedance path to the supply 
> rail) so you'll probably want some sort of pull-up on the output 
> (unless there is already one in the motor control).  If there's noise 
> around your spindle motor (likely) this could be why you're having 
> problems at low speed when the FET is mostly off. 
> -- 
> Charles Steinkuehler 
> <javascript:> 

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