Re: Save and Restore parameters

[Tim Mooney <mooney@aps.anl.gov>]

Julio,
Autosave may be able to do what you want.  If the list of PVs to be saved will not normally change between ioc reboots, it would be convenient to use autosave's "create_triggered_set()" command in an ioc-startup command file.

If you do this, autosave will save listed PVs to a file whenever a "trigger" PV is posted.  This may not be what you want.  If you want autosave to save only if when a specified PV takes on a certain value, you could write a database that would accomplish that.  (I think I would start with a calcout record, and use it's OOPT and OUT fields to write conditionally to the autosave trigger PV.)

Currently, the restore operation can happen at boot time, or in response to the command "fdbrestoreX()" typed into the ioc console.  It is possible for the restore to occur in response to a PV, but that takes custom code. As it happens, I've been working on that the past few days.  I have something that works, but it's not very robust and doesn't handle errors.  I think a really good solution for would require some additional infrastructure built into autosave.

Tim

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From: "Julio Calvo" <julitocal_24@yahoo.es>
To: tech-talk@aps.anl.gov
Sent: Monday, March 11, 2013 11:26:08 AM
Subject: Save and Restore parameters

Hi folks,

I would like to know if somebody here has any clue or maybe has developed something similar to this (I think it should be quite common):

I need to save and restore some parameters in a LLRF system based on EPICS. I am using AsynPortDriver and CSS. Once an interlock happens (a bi change to true, for example) I need the system to figure it out and save all the PV's values to a file, then I need to restore them. The solution should be different from the archiving system, I am not able to develop archiving in my system.

Thank you so much for your help.

Cheers.

 

Julio.