Experimental Physics and
Industrial Control System

Benjamin Franksen <[email protected]> · Fri, 26 Oct 2007 12:28:00 +0200

On Thursday 25 October 2007 16:58, Jeff Hill wrote:
> > Now the problem is that if I change the limit field then well.
> > MEDM just doesn't know about it.
> > So how do I get that part to run again?
> > Or is this another one of those impossible things :(
>
> Unfortunately, it's not currently possible for MEDM, or any other EPICS
> client, to subscribe for updates to be sent when there are changes in the
> limits. Therefore, most clients fetch the limits when they connect and
> assume that they don't change after that. Perhaps that might explain
> EDM's behavior.
>
> Note that MEDM will update its limits if its forced to reconnect.

My usual work around for this is to add a related-display-button to the 
display which re-opens the same display. Obviously, this is a solution only 
if the limits change in response to a user request, so it might not 
applicable in your (the OPs) situation.

It would help if display clients allowed the user to chose dedicated 
independent PVs (e.g. myRecord.HOPR) for display limits, falling back to 
the CA provided limits if no dedicated PV has been configured.

Cheers
Ben

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System