40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Message ID: 13898     Entry time: Wed May 30 16:12:30 2018
Author: Jonathan Hanks 
Type: Summary 
Category: CDS 
Subject: Looking at c1oaf issues 

When c1oaf starts up there are 446 gain channels that should be set to 0.0 but which end up at 1.0.  An example channel is C1:OAF-ADAPT_CARM_ADPT_ACC1_GAIN.  The safe.snap file states that it should be set to 0.  After model start up it is at 1.0.

We ran some tests, including modifying the safe.snap to make sure it was reading the snap file we were expecting.  For this I set the setpoint to 0.5.  After restart of the model we saw that the setpoint went to 0.5 but the epics value remained at 1.0.  I then set the snap file back to its original setting.  I ran the epics sequencer by hand in a gdb session and verified that the sequencer was setting the field to 0.  I also built a custom sequencer that would catch writes by the sdf system to the channel.  I only saw one write, the initial write that pushed a 0.  I have reverted my changes to the sequencer.

The gain channel can be caput to the correct value and it is not pushed back to 1.0.  So there does not appear to be a process actively pushing the value to 1.0.  On Rolfs sugestion we ran the sequencer w/o the kernel object loaded, and saw the same behavior.

This will take some thought.

ELOG V3.1.3-