g+
g+ Communities
Argonne National Laboratory

Experimental Physics and
Industrial Control System

1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  <20132014  Index 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  <20132014 
<== Date ==> <== Thread ==>

Subject: epics input and output via records
From: James F Ross <james.falconer.ross@gmail.com>
To: EPICS Tech Talk <Tech-talk@aps.anl.gov>, Joachim Schambach <jschamba@physics.utexas.edu>
Date: Mon, 7 Jan 2013 10:20:00 -0500
Hello all,
A colleague of mine and I are trying to set up an IOC for an HLT power supply.  Basically the power supply has an internal memory that will remember the voltages that it was set to when it was previously turned off.  These are changed while the IOC runs for various reasons and it is desirable that the IOC also remember what these voltages were.

What is currently happening is if the IOC has to be restarted, it loads the default setpoint values in the db files and we lose the current settings in the power supply.  We have a workaround in place, setting the values by DOL fields in the output records, but we are having trouble using anything other than a hard value (like 5.0 rather than a variable).  What would be ideal is if the IOC on start up could read the value from the power supply and output that value via the DOL.  Is there a way in, say, an ao record to get the value that was read in by a corresponding ai record and output that value?  How do you call one record in another within the db file? 

An alternative would be to prevent the IOC from changing any values at all on start up...  For this approach if anyone could let us know what field types and records are generally used to change the value of a variable, that would help us hunt down what to change in the db files.

If anyone also has any suggestions on how this kind of thing is most commonly handled in EPICS that would be helpful as well.

Let me know if my question is confusing and I can try to clarify.
Thanks!
James



Replies:
RE: epics input and output via records Mark Rivers
Re: epics input and output via records Andrew Johnson

Navigate by Date:
Prev: Re: streamDevice: how to read a value as fast as possible? Dirk Zimoch
Next: RE: epics input and output via records Mark Rivers
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  <20132014 
Navigate by Thread:
Prev: RE: streamDevice: how to read a value as fast as possible? Mark Rivers
Next: RE: epics input and output via records Mark Rivers
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  <20132014 
ANJ, 31 Jan 2014 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· EPICSv4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·