On Tue, 6 Aug 2013, andy pugh wrote: > Date: Tue, 6 Aug 2013 18:53:45 +0100 > From: andy pugh <[email protected]> > Reply-To: "Enhanced Machine Controller (EMC)" > <[email protected]> > To: "Enhanced Machine Controller (EMC)" <[email protected]> > Subject: Re: [Emc-users] A puzzler > > On 6 August 2013 18:46, Peter C. Wallace <[email protected]> wrote: > >> Do you have the interpolator specifications? > > https://docs.google.com/file/d/1gap4oQlfy43X7s-AZkXDH8gTI8L8HSQhr2rze8b8SEMmT_EyHwaHr7i8MGu1/edit?usp=sharing > >> some have quite large quadrature >> distortion (large deviations from 90 degree phasing) which may cause the >> 7I77/5I25 to lose counts. > > That's an interesting possibility. > >> Also is the encoder filter on or off? > > He has tried both. > > I will forward the rest of the info. > > -- > atp Heres a direct link:
http://www.ichaus.de/NQC_datasheet_en Looks like 64X or 32X would be the maximum interpolation ratio without using a higher mux frequency. 256X requires an equivalent counting frequency of about 8MHz. This is out of the range of muxed encoders. So a couple options to try in order of difficulty: 1. Set interpolation ratio lower 2. Raise the MTD if that can be set easily 3. use non muxed counters (a config can be made that only has 3 non muxed counters. these have a 33.3 MHz sample rate so 90 ns minimum pulse detection and > 10 MHz count rate) 4. use the BISS or SSI interfaces > If you can't fix it, you don't own it. > http://www.ifixit.com/Manifesto > > ------------------------------------------------------------------------------ > Get 100% visibility into Java/.NET code with AppDynamics Lite! > It's a free troubleshooting tool designed for production. > Get down to code-level detail for bottlenecks, with <2% overhead. > Download for free and get started troubleshooting in minutes. > http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk > _______________________________________________ > 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. ------------------------------------------------------------------------------ Get 100% visibility into Java/.NET code with AppDynamics Lite! It's a free troubleshooting tool designed for production. Get down to code-level detail for bottlenecks, with <2% overhead. Download for free and get started troubleshooting in minutes. http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
