Experimental Physics and
Industrial Control System

Dirk Zimoch <[email protected]> · Mon, 26 Sep 2005 09:47:18 +0200

That happens when the data range (here: 4.7e4) is much larger than the
axis range (here: 100). This seems to be a bug in the Striptool display
routine. I have seen this effect often.
Dirk
Laznovsky, Michael wrote:

Hi all-
For a while now I've noticed an odd effect in one of my ongoing striptool

charts... one of the PVs I follow starts at zero when an IOC is booted and
just counts up from there, one step every 3.7 seconds or so, as you can see
on this full-scale chart ("LM20:DATA:COUNT", the diagonal maroon line):
http://www-user.slac.stanford.edu/lazmo/tmp/lm20-stripbug2.gif
But when striptool is set to user-specified axis limits, that PV mysteriously
keeps regularly reappearing in the interval (0,100) as though it had been
reset to zero:
http://www-user.slac.stanford.edu/lazmo/tmp/lm20-stripbug.gif
The phantom period looks to be about 5.5 hours, which translates to about

19800 seconds, or 5300 counts of the PV; apparently not an obvious power-of-2
wrap-around effect in this case.
Haven't seen any other PVs do this, but then I don't follow any other
monotonically-increasing ones.  No big deal, unless it reveals some underlying
bug that may be subtly affecting other displays.
Any ideas??
thanks,
Mike
-----
Michael P. Laznovsky                         mailto:[email protected]
Application Software Developer, ESD                     ofc: (650) 926-2924
Stanford Linear Accelerator Center, MS-46               fax: (650) 926-3515
2575 Sand Hill Road, Menlo Park CA 94025 USA   http://www.slac.stanford.edu

--
Dr. Dirk Zimoch
Swiss Light Source
Paul Scherrer Institut
Computing and Controls
phone +41 56 310 5182
fax   +41 56 310 4413

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System