On Saturday 26 July 2014 23:46:50 Russel Ingram did opine And Gene did reply: > I'm trying to get a Beaglebone Black with a Xylotex parallel port cape > to drive a Gecko G540 and everything works fine if I want a plain old > three axis setup, but my ultimate goal is to have a pair of steppers > that both take the same step commands but in opposite directions to > drive opposite ends of the Y axis on the router I'm building. It looks > pretty simple in the parport hal I had when I had it hooked up to a > PC, but the PRU hal examples seem a bit less straightforward. Is it > possible to do this with the PRU driver? > I would setup 2 drivers from one stepgen, and reverse a winding on one motor. That way you don't have to worry about the backwards motor, just wire it that way and you don't have to putz with the software portion.
That will of course need a small patch board cut into the parport cable between the parport and the xylotex so one stepgen is sent to 2 drivers on the xylotex card. The std cable can't do that. I do think I'd not do a final torque up on the motor couplings until I had let one of them slip enough at driver powerup time so the motors aren't fighting each other by half a step. At powerup, the xylotex's come up in a consistent state. If the couplings are then locked down after allowing that slippage, it should be good till the next time you take it apart. There are other ways, and you should use the one that fits your needs best, this may not be it, its just one way. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck Code Sight - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
