On Tue, 18 Aug 2009, Steve Blackmore wrote: > Date: Tue, 18 Aug 2009 22:16:48 +0100 > From: Steve Blackmore <st...@pilotltd.net> > To: Peter C. Wallace <p...@mesanet.com>, > EMC2-Users-List <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] Realistic spindle encoder count for parallel port? > > On Mon, 17 Aug 2009 16:54:54 -0700 (PDT), you wrote: > > >> If I get a free bit of time I'll cobble together a quadrature divider, >> basically: >> >> 1. Input digital filter >> 2. Quadrature decoder (quadrature to up/down) >> 3. Up down modulo N counter (for divide by N) >> 4. 2 bit up/down counter >> 5. 2 bit binary --> quadrature encoder >> 6. Optional index stretcher >> >> I even think we have some CPLD bds we never used that I can send over for >> shipping cost. > > That's very kind of you Peter, I'd appreciate that very much. From > experiments looks like the index stretcher is a must ;) > > I'm not happy with the Chinese 1024 pulse encoder, but I've also got an > unused Stegmann DG60L 500 pulse per rev encoder I'm going to test. > Looking at the docs that too only outputs a single quadrature count > index pulse, but it's much better quality and I'm hoping the signals out > from it are cleaner. > > Steve Blackmore > -- >
I'll have some time at the end of the week and Ill put something together. I'll also try and make the long index synchronous with the divided Quadrature this will require the total encoder counts to be evenly divisable by the divide ratio. If I fail at that I'll just use a digital one-shot Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users