EMC2 simply generates pulses. Each pulse rotates the shaft a specific number of degrees. The direction signal controls which way the motor turns. Typically there is a controller chip that handles this.
Some links: http://www.imagesco.com/articles/picstepper/02.html http://en.wikipedia.org/wiki/Stepper_motor I searched on Google for "how stepper motors work". Hope that helps. Andy Dave Merriman wrote: > I'm new to EMC and CNC, and have been trying to get my head around what's > going on with EMC and a CNC machine. > > I've gone through (read) the CNC setup process a couple of times, and I have > to admit that I'm still a bit confused. > > What I'm not understanding, really, is just exactly _what_ EMC is dispensing > through the parallel port. It makes sense that the level of detail/control > varies with the sophistication of the CNC machine; what I'm not real clear on > is *how*. > > Using the example of a 'basic' stepper motor machine with X/Y/Z axes > (axises?), and the parallel port having Step and Direction output pins for > each axis: is EMC actually sending out a step/direction bit for every single > position change (i.e. step of the stepper motor)? EMC would control how fast > the Step pulses were sent so as to control how fast the stepper motor turned, > yes? How is the output for a 'dumb' machine different from that for something > more advanced? > > I know these are pretty basic questions, but a Google search didn't turn up > anything with this level of detail (at least, not in the first 20 or so pages > of results!). If there exists a site or document that explains these kinds of > gory details, I'd certain welcome the redirection. > > DaveM -- Andy PGP Key ID: 0xDC1B5864 ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
