RE: Disable PVs processing based on some condition

[Abdalla Ahmad via Tech-talk <tech-talk at aps.anl.gov>]

Hello Ralph

 

Thanks for your suggestion. This works well and even suitable as a runtime configuration without the need for an IOC but it has the same behavior as with the dfanout setup. I set SDIS to “TestPV CP” and DISV to the disable value and the PV does not get processed while TestPV equal DISV, If I change the PV while it is disabled, it will be processed with that value when TestPV is not equal to DISV.

 

Best Regards,

Abdalla.

 

From: Tech-talk <tech-talk-bounces at aps.anl.gov> On Behalf Of Ralph Lange via Tech-talk
Sent: Monday, November 14, 2022 12:10 PM
To: EPICS Tech Talk <tech-talk at aps.anl.gov>
Subject: Re: Disable PVs processing based on some condition

 

On Mon, 14 Nov 2022 at 09:10, Abdalla Ahmad via Tech-talk <tech-talk at aps.anl.gov> wrote: 

I would like to disable processing for certain PVs based on some condition, I used the DISA field by writing 1 to it in a dfanout record from a calcout record (OUT field). The setup is working fine but with a strange behavior (which might be expected). Writing anything to DISA does not take effect until the PV is processed, so I had to make another fanout record only to process those PVs whenever the calcout record is processed (FLNK). Now assume if the condition is met and the PVs got disabled, if you write anything to the PV, it will not process it but on the next change from calcout. This can be problematic in certain setups. Is there any way to avoid writing at all when the PV is disabled? Or a better way to disable PVs? Thanks.

 

What about skipping the dfanouts / fanouts and just pointing the SDIS links of all to-be-conditionally-disabled records to the condition calc? If you make these SDIS links CP, the target records will be processed when the disable condition changes.

 

Cheers,

~Ralph