On Thu, 15 Feb 2007, Gene Heskett wrote: > Date: Thu, 15 Feb 2007 15:44:32 -0500 > From: Gene Heskett <[EMAIL PROTECTED]> > Reply-To: "Enhanced Machine Controller (EMC)" > <[email protected]> > To: [email protected] > Cc: Jon Elson <[EMAIL PROTECTED]> > Subject: Re: [Emc-users] Hardware step generator for 5I20 > > On Thursday 15 February 2007, Jon Elson wrote: >> [EMAIL PROTECTED] wrote: >>> "Peter C. Wallace" <[EMAIL PROTECTED]> wrote: >>>> Step/DIR or quadature output selectable per generator. >> >> My UPC has had quadrature output available since I developed it. I >> don't think more >> than one user actually used the feature, and he was using an absolute >> minimum >> driver, just power transistors. But, yes, it seems to have significant >> advantages >> over step/direction! >> >> Jon > > Generally I have to agree Jon, as the smoothest, most accurate mouse any > of us has ever used was the decoded quadrature output amiga mouse of > yesteryear, but it comes to mind, how does one handle the microstepping > when using the quadrature signals if you can't step back and forth > through the lookup table of desired currents using that?
Quadrature is just an alternate way of taking steps (or microsteps) in either direction. It has the advantage that it does not have the direction --> step setup time problems that step/direction counters suffer from. This is because is it a 2 bit Grey code where only on bit can change at a time. > > That would also seem to restrict you to 1/4 step resolutions unless the > lookup table was two full cycles wide. Then one almost needs an index > pulse too... > > Or am I miss-understanding the actual implementation? > > -- > Cheers, Gene > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > Yahoo.com and AOL/TW attorneys please note, additions to the above > message by Gene Heskett are: > Copyright 2007 by Maurice Eugene Heskett, all rights reserved. > > ------------------------------------------------------------------------- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to share your > opinions on IT & business topics through brief surveys-and earn cash > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
