Re: low pulserate / cycletime / G02?

[Max Heise <mahe-at-bandstahlschnitte.de>]

Hello Oliver,

I can not comment on the steppers, I am using servos, but
> Another Problem:
> 
> When I'm driving a complete circle, starting from X10 Y0,with the command
> 
> G02 X10 Y0 I-10 J0
> 
> EMC does the circle twice?

An old and solved problem, you are running some old release and not CVS, are
you ? The was a problem between the posmath library and a workaround for that
problem in emccanon.cc. 
Look for the function ARC_FEED in the source, the file
is emctask/emccanon.cc The mod. histroy says the following about ARC_FEED:
  7-Mar-2000  FMP changed ARC_FEED to limit feed rate to axis max
  velocities, as was done for STRAIGHT_TRAVERSE below.
  3-Mar-2000  FMP changed STRAIGHT_FEED to limit feed rate to axis max
  velocities, as was done for STRAIGHT_TRAVERSE below.
  23-Feb-2000  FMP changed STRAIGHT_TRAVERSE to use maximal feed rate based
  on individual axis max feed rates. Added CANON_UPDATE_POSITION() to handle
  updating canonEndPoint when move was aborted.
  22-Feb-2000 WPS modified ARC_FEED again. In the previous fix I included
  some additional unnecesary  and incorrect conditions for detecting the full
  circle that results in too many rotations.
  2/7/00 WPS modified ARC_FEED to add an additional rotation when
  the starting and ending positions are equal.           

In the CVS source the line concerned look like this
#if 0  // This should not be needed anymore with fix in _posemath.c
    // If starting and ending on same point move around the
    // circle, don't just stay put.
    if (full_circle_in_active_plane) {
      rotation++;
    }
#endif    
and
#if 0  // This should not be needed anymore with fix in _posemath.c
    // If starting and ending on same point move around the
    // circle, don't just stay put.
    if (full_circle_in_active_plane) {
      rotation--;
    }
#endif 

So just comment out that out in your source or upgrade to latest CVS. And
recompile.

Regards
Max

-- 
Max Heise <max.heise-at-gmx.net>
Student Mechatronik/Automatisierungstechnik
PGP public key from:
http://www.fht-esslingen.de/~mahemt01/pgp50i.pub or any keyserver