On Sat, 17 Mar 2012, Scott Hasse wrote: > Date: Sat, 17 Mar 2012 10:43:56 -0500 > From: Scott Hasse <scott.ha...@gmail.com> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] Voltage to frequency for analog input > >> But this is really really wasteful > > Presuming my PC can handle a reasonable base-thread rate, is it really > wasteful of a scarce resource?
Depending on the thread rate, you may use 20% or more of your PCs horsepower doing I/O. Also the hardware encoder counter will do a better job of frequency counting, even high res counting of low frequencies (it uses a 1MHz timestamp for inverse time frequency calculation) than the software encoder counter (which uses the jittery basethread for timestamping). > > It seems if I want to use a "real" encoder counter given my configuration > I'll need a custom 5i23 firmware? Possible but since you only need one more encoder counter, theres possibly a bitfile that will do (depending on what other functions you have) > > Thanks! > > Scott > > On Sat, Mar 17, 2012 at 10:01 AM, Peter C. Wallace <p...@mesanet.com> wrote: > >> On Sat, 17 Mar 2012, Scott Hasse wrote: >> snip---------------------------------------------------------------------- >>> >>> It acts like it is sampling the encoder at the servo-thread frequency, >>> despite the update-counters function being bound to the base-thread. >> When >>> I view the configuration from axis, the base-thread does show the >>> encoder.update-counters >>> function bound to it. >> >> >> You probably are sampling at the servo thread, to avoid this you would >> have to >> do the the hm2_read at the base thread. >> >> But this is really really wasteful, much better to use a real encoder >> counter >> (and dump the base thread sucking computer resources altogether) >> >> Peter Wallace >> >> >> >> ------------------------------------------------------------------------------ >> This SF email is sponsosred by: >> Try Windows Azure free for 90 days Click Here >> http://p.sf.net/sfu/sfd2d-msazure >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > ------------------------------------------------------------------------------ > This SF email is sponsosred by: > Try Windows Azure free for 90 days Click Here > http://p.sf.net/sfu/sfd2d-msazure > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > 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. ------------------------------------------------------------------------------ This SF email is sponsosred by: Try Windows Azure free for 90 days Click Here http://p.sf.net/sfu/sfd2d-msazure _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
