On Sunday 08 September 2019 06:55:58 Peter C. Wallace wrote: > On Sun, 8 Sep 2019, andy pugh wrote: > > Date: Sun, 8 Sep 2019 10:50:54 +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] Step > > timing and max velocity > > > > On Sun, 8 Sep 2019 at 04:41, andrew beck <[email protected]> > > wrote: > > > >I can move the table at max speed but the Stepgen PID errors out. > > > > > >Can you elaborate on this? > >PID has no error messages, as far as I know. So what is the actual > > error? > > > >What is PID.n.maxerror set to? > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > I almost guarantee this is the issue, Some earlier versions of pncconf > set this to .0005 as a way to make the stepgen more robust with regard > to host servo thread jitter but the number only makes sense in inches > so fails on metric machines. This should be set so say .0127 on metric > machines (or just 0) to disable the correction limit completely. > > Other values: > FF1 = 1.0 > P= 1/servo period (so normally 1000) > and if you are very fussy: > FF2 = seconds from position read to velocity write > about 0.0001 on Ethernet cards
And that is the first time I've seen a spec for FF2 that makes any sense, thank you Peter. What would be roughly correct for a 5i25-7i76 combo? > >Is your FF1 correct? In a cruise, using > >halscope, you should see the > >velocity command and the actual velocity pretty much equal. > > > >-- > >atp > >"A motorcycle is a bicycle with a pandemonium attachment and is > > designed for the especial use of mechanical geniuses, daredevils and > > lunatics." ÿÿ George Fitch, Atlanta Constitution Newspaper, 1916 > > > >_______________________________________________ > >Emc-users mailing list > >[email protected] > >https://lists.sourceforge.net/lists/listinfo/emc-users > > Peter Wallace > Mesa Electronics 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) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
