Re: Spindle RPM

[Jon Elson <jmelson-at-artsci.wustl.edu>]

Paul Corner wrote:

> > >BTW Is there an [EMC_????] function to return the spindle speed to tkemc ?
>
> > This is one of the things we'll need before long.  Would you want a quad
> encoder input or just a tick every revolution?
>
> I had in mind just a simple routine to count a tick per rev. It need not be
> high resolution, + or - 10% is near enough to display on the tkemc GUI I've
> butchered. - I've left a copy in the Linuxcnc drop box tkemc-PC_2.gz . It's not
> much, but it gives me a reason to play with this tcl/tk thing.

Well, a quadrature encoder with Index would be needed for threading on the
lathe.  Also, if you had a low-res quadrature encoder, the counters in the STG
card could read the counts and give you the information with no special
hardware.  This would be easy on servo systems, but wouldn't do any good
for stepper systems.

Jon