Re: Aug-30-99 EMC release set free

Hi Fred,

I tried both commanded and actual and get the same result although, as
my machine will use stepper motors I would expect to use commanded
values until I get a DRO set up. The reason I mentioned it is that it
only seems to affect the 'x' axis and happens
even when there is nothing connected to the port. If the resolution is
reduced to 0.0100 per step or less, it seems to correct itself but, for
anything finer than this it seems I would have to home it then change
resolution to 0.0001 and jog the axis to exact zero manually. As the
other axes don't exhibit the same effect I thought it was probably a
minor software problem but it may, of course, just be an anomaly with my
machine. I expect other users could comment on this. Also, is it normal
for the digits on the screen to noticeably flicker as a g-code script
runs? I assume it is a factor of the refresh rate but wonder if it could
be stabilised in future developments. I noticed your comments on 4-axis+
use of EMC in another post and didn't understand a word of it! Since I
will need at least 4 axes, is there any chance you could do a kind of
short 'idiots guide' to setting this up please - I'm sure others on the
list would also be very grateful for this. Thanks,

Ian

Fred Proctor wrote:

>
> Ian W. Wright wrote:
>
> > When I try to home the axes in Jog(Manual) mode,
> > the 'x' axis almost always fails to zero exactly, i.e. it finishes on
> > 0.0001 or -0.0001(sometimes -0.0002). The other axes zero exactly. Also
> > I have noticed that, if I jog the 'x' axis in 0.001 increments it goes
> > 0.0100, 0.0110, 0.0120 etc up but 0.0109, 0.0099, 0.0089 etc down. I
> > don't see this as being a particular problem and when running G-code
> > scripts in step mode, they always seem to finish on the right figures

> Are you displaying commanded or actual coordinates? Normally you display
> actual coordinates so you can see where the machine actually is. You can
> select which numbers are displayed from one of the xemc menus. If you
> are displaying actual values, you may simply be off a bit, and
> increasing the P gain would help. If you are displaying commanded
> values, then this is a software problem. I haven't seen this myself but
> it could be roundoff in the display code.

--

Ian W. Wright LBHI
Sheffield Branch Chairman of the British Horological Institute.
Bandmaster and Euphonium player of the Hathersage Brass Band. UK.
See our homepage at:- http://www.iw63.freeserve.co.uk or
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'Music is the filling of regular time intervals with harmonious
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