On Sat, 22 Feb 2014, Mark Tucker wrote: > Date: Sat, 22 Feb 2014 19:20:57 +0000 > From: Mark Tucker <m...@rmtucker.f2s.com> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] Crackling motors using Beaglebone > > John > > Thank you so much for the insight of how that work and it explains a lot. > But as you stated it would be hunting back and forth.Which i assume it > would have to pulse the step line? > And a number of people have scoped the outputs and only found the Dir > line hunting back and forth,i wonder why it is not detected on the step > line.? > And if it is only the dir line,why would the motors make a noise at all?
The internal stepgen position has a resolution of a small fraction of a step (1/10000 of a step in Johns example) so it can hunt back and forth without emitting a step. As to why a step drive pays any attention to the dir signal without a step pulse I do not know, seems like a mistake to me. Peter Wallace Mesa Electronics ------------------------------------------------------------------------------ Managing the Performance of Cloud-Based Applications Take advantage of what the Cloud has to offer - Avoid Common Pitfalls. Read the Whitepaper. http://pubads.g.doubleclick.net/gampad/clk?id=121054471&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
