EPICS Home EPICS Controls Argonne National Laboratory

Experimental Physics and
Industrial Control System

Format page
for printing


Search Tech-talk
1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024  Index 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024 
<== Date ==> <== Thread ==>
Subject: RE: Timestamping Confusion
From: "Manoussakis, Adamandios via Tech-talk" <tech-talk at aps.anl.gov>
To: EPICS tech-talk <tech-talk at aps.anl.gov>
Date: Mon, 14 Dec 2020 21:32:09 +0000

Thank you both for the insight, it seems best for us to go a similar path of using TSEL to copy the timestamp from the digitizer to each of our waveform records and using TSE set to -2 to stop the IOC from overwriting the time field (please correct me if I am wrong on this). I think I just need to understand the best way to get the first timestamp and then use TSEL to pass it along to the other records.

 

Ralph when you stated to have the digitizer send the timestamp with the data, would I just have my digitizer set the TIME field in the waveform record then?

 

 

 

From: Tech-talk <tech-talk-bounces at aps.anl.gov> On Behalf Of Ralph Lange via Tech-talk
Sent: Saturday, December 12, 2020 5:25 AM
To: EPICS Tech Talk <tech-talk at aps.anl.gov>
Subject: Re: Timestamping Confusion

 

On Fri, 11 Dec 2020 at 22:33, Manoussakis, Adamandios via Tech-talk <tech-talk at aps.anl.gov> wrote:

Thanks for the comments Michael, when you are dealing with hundreds of waveform records and the timestamps are being taken when each record is processed (I would assume these would all be off by some delay if multiple softIOCs are running) do you then just have a master time waveform to lineup all your other signals to t0?  It seems the digitizer would have a time stamp of t0 for all of its signals but the epics records would not all align at the same timestamp since each one isn't processed at t0 to be timestamped.

 

The EPICS Device Support needs to know the timestamp t0 (preferably sent with the data by the digitizer) and write it to each record's timestamp when it updates the record.

In that case, by configuring their TSE to -2, all waveform records can use the digitizer timestamp. That timestamp can even be forwarded (using TSEL) through post-processing chains, so that processed data may still use the timestamp that the digitizer sent with the raw data at the beginning of the chain.

 

Cheers,
~Ralph

 

Replies:
RE: Timestamping Confusion Manoussakis, Adamandios via Tech-talk
References:
Timestamping Confusion Manoussakis, Adamandios via Tech-talk
Re: Timestamping Confusion Michael Davidsaver via Tech-talk
RE: Timestamping Confusion Manoussakis, Adamandios via Tech-talk
Re: Timestamping Confusion Ralph Lange via Tech-talk
Navigate by Date:
Prev: Re: ioc startup files not installed to INSTALL_LOCATION Matt Rippa via Tech-talk
Next: Help Erika Jones via Tech-talk
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024 
Navigate by Thread:
Prev: Re: Timestamping Confusion Ralph Lange via Tech-talk
Next: RE: Timestamping Confusion Manoussakis, Adamandios via Tech-talk
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024 
ANJ, 14 Dec 2020 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· Search · EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·