Argonne National Laboratory

Experimental Physics and
Industrial Control System

1994  <19951996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  Index 1994  <19951996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017 
<== Date ==> <== Thread ==>

From: carr_g@aotmail.atdiv.lanl.gov (Gary P. Carr)
To: tech-talk@aps.anl.gov
Date: Wed, 18 Oct 1995 11:43:12 -0800
Here at LANSCE (we used to be LAMPF) we are converting an older VAX/PDP-11
based control system to EPICS. We are running  EPICS 3.11.4 on Sun OS 4.4
using SPARC 5s for our control system OPIs. We are also using tcl/tk for
some applications. I built a version of wish using tcl 7.3, tk 3.6, blt
1.7, and a version of tcl channel access that I got from CEBAF and modified
to include some additional features we wanted (including connection
management).

We are having problems with one tcltk program which uses the blt_barchart
widget. This is a Beam Loss Monitor application that uses four blt_barchart
widgets, each with about 70 to 80 bars. The barcharts use three dimensional
bars displaying percent of loss. The bars are color coded to show the alarm
status of the loss monitors. They also use stipple patterns and  tags to
indicate various other conditions. The program has monitors set on about
500 channels and updates the barcharts at 1 Hz. After the initial startup
the number of bars that change at a given update may reach 50/sec or more,
but are more typically around 5-10/sec.

The program works fine, except that it periodically dies with an Xlib error:

X Error of failed request: BadIDChoice (invalid resource ID chosen for this
connection)

Major opcode of failed request: 55 (X_CreateGC)

The time it takes to die seems to be dependent on update activity. It
varies from as little as 30 minutes to 7 or 8 hours. This looks very much
like a known error in Xlib that has shown up in tcltk before. According to
Ousterhout it is caused by Xlib's failure to handle wrap-around of X
resource identifiers. It is supposed to be fixed in tk 4. I built a new
version using tk4.0, tcl7.4 and a patched version of blt called blt-1.8.
There was no change, the program still gets the same error with about the
same timing.

Has anyone seen similar problems with tcl/tk or with blt widgets using tk4.0?


----------------------------------------------------------------------------
Gary P. Carr                                                  gcarr@lanl.gov
Staff Member, AOT-6                                             505-667-5785
Los Alamos National Laboratory                            (fax) 505-665-0046
----------------------------------------------------------------------------



Navigate by Date:
Prev: Programming the mv162 flash memory for vxWorks winans
Next: Re: Medm and XRT/Graph Bill McDowell
Index: 1994  <19951996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017 
Navigate by Thread:
Prev: Programming the mv162 flash memory for vxWorks winans
Next: Re: Medm and XRT/Graph Bill McDowell
Index: 1994  <19951996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017 
ANJ, 10 Aug 2010 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·