Re: Is the Sequencer and SNL still widely used?

["Mooney, Tim M. via Tech-talk" <tech-talk@aps.anl.gov>]

One more point that hasn't been mentioned: custom code that isn't associated with a single record needs to use Channel Access, and SNL makes this easy, with ways to do Channel Access calls that would require lots of code - stuff like put-callback, acting on monitors, involving multiple execution threads, etc. So SNL is not obsolete, not even for problems that don't call for state machines.

Tim Mooney (mooney@anl.gov) (630)252-5417
Beamline Controls Group (www.aps.anl.gov)
Advanced Photon Source, Argonne National Lab

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From: Tech-talk <tech-talk-bounces@aps.anl.gov> on behalf of Murray, Doug via Tech-talk <tech-talk@aps.anl.gov>
Sent: Friday, April 14, 2023 10:22 AM
To: Hu, Yong <yhu@bnl.gov>; tech-talk@aps.anl.gov <tech-talk@aps.anl.gov>
Subject: Re: Is the Sequencer and SNL still widely used?

 

Thanks everyone for the great response, including all those sent to me personally.  To summarize those sent directly to me, they mirror what’s been indicated in this forum; the sequencer is indeed alive and well and used in a variety of settings at many (most?) EPICS sites.

But to answer your question Yong (and similar ones asked directly!) this comment about the sequencer came up in a small internal meeting with some people who are quite focused on very specific EPICS-related work that doesn’t require the sequencer.  SLAC has many hundreds of IOCs that do use the sequencer, so it’s great that EPICS as a toolkit can support a broad spectrum of users.

 

cheers

-doug

 

 

From: Hu, Yong <yhu@bnl.gov>
Date: Friday, April 14, 2023 at 5:58 AM
To: Murray, Doug <drm@slac.stanford.edu>, tech-talk@aps.anl.gov <tech-talk@aps.anl.gov>
Subject: Re: Is the Sequencer and SNL still widely used?

This topic is becoming so hot that I cannot help jumping in. I cannot imagine a facility (not a simple lab setup) using EPICS without using Sequencer. Doug, is that meeting at SLAC just internal?

Yong HU
on behalf of NSLS-II using Sequencer

From: Tech-talk <tech-talk-bounces@aps.anl.gov> on behalf of "Murray, Doug via Tech-talk" <tech-talk@aps.anl.gov>
Reply to: "Murray, Doug" <drm@slac.stanford.edu>
Date: Thursday, 13 April 2023 at 18:37
To: "tech-talk@aps.anl.gov" <tech-talk@aps.anl.gov>
Subject: Is the Sequencer and SNL still widely used?

 

At a recent meeting at SLAC, it was suggested that the EPICS Sequencer and its State Notation Language has become obsolete.  Are any sites other than SLAC still using this?  I assume so, but please let me know directly if your organization is using it, and I can summarize later.

 

cheers

-doug