On Sun, Oct 28, 2018 at 10:59 AM Peter C. Wallace <[email protected]> wrote:
> On Sun, 28 Oct 2018, Chris Albertson wrote: > > > Date: Sun, 28 Oct 2018 10:41:14 -0700 > > From: Chris Albertson <[email protected]> > > Reply-To: "Enhanced Machine Controller (EMC)" > > <[email protected]> > > To: "Enhanced Machine Controller (EMC)" <[email protected] > > > > Subject: Re: [Emc-users] 5I25-7i76 encoder output > > > > On Sun, Oct 28, 2018 at 5:15 AM andy pugh <[email protected]> wrote: > > > > The Mesa Encoder uses both methods combined = delta_counts/delta_time, so > for > example if you have 7 counts between servo thread times, the velocity will > be > calculated as 7/(time from first to last edge of those 7 counts) > This is optimum for most uses. > Yes, that woud work well. So many times they effecivly divide by the sample period and don't actualy measure the actual times of the edges. This gives them a the kind of jitter in RPM that was reprted. So how does it work? There must be a micro or nano second counter on the FPGA that gets sampled. -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
