[Emc-developers] FAQs, Doco, User Mail List of no help

[Phill & F. G. <gla...@bi...>]

Gentle people,
	I have trawled the FAQs and doco for some help with a problem I have. I 
have also posted to the EMC User mail list , again, no help.

You are my last hope.

I have built a CNC mill from scratch, loaded and configured EMC BDI.

The problem I am experiencing is that I cannot make INPUT_SCALE (and 
OUTPUT_SCALE) small enough to reflect a configuration where I have 
200steps/rev and 1.25mm direct coupled lead screws.
 From the doco I can find the value of I_S and O_S should be the "Number of 
pulses required to move the axis 1 User Unit". That means INPUT_SCALE 
should be set to "160".

If I set I_S to any value below about "500", and test the distance 
travelled, the axis will move at DEF_MAX_VEL for the required distance, but 
then *continues* to move in the same direction at a slightly lesser speed 
(seems to be around 50Hz) I don't believe there is any cross-talk from my 
240v circuitry, because at values above "500" there are no problems. The 
only way I can stop the axis from moving is to "exit" EMCtk.

At the moment I have I_S and O_S set to 1600 and am designing my parts at 
one tenth scale so that they are cut at full size.

Any help would be greatly appreciated.

There are some pictures at http://www.glasson.org and follow the CNC links.

TIA,
Phill.