RE: Make waveform from ai record

[Žiga Oven via Tech-talk <tech-talk at aps.anl.gov>]

Hi Abdallah,

 

Another way, is to clear/reset the compress record, once the number of samples reaches 200…

 

You can do this by looking at the NUSE field and once it reaches the value 200, you can extract the waveform and reset the compress record by writing to RES field.
Do keep in mind that this might be an “expensive” option, as you will have additional records, and you will be overwriting the compress record value with 0s on each reset.

 

Best regards,

 

Žiga

 

 

 

From: Tech-talk <tech-talk-bounces at aps.anl.gov> On Behalf Of Ralph Lange via Tech-talk
Sent: Monday, February 24, 2025 11:32
To: EPICS Tech Talk <tech-talk at aps.anl.gov>
Subject: Re: Make waveform from ai record

 

On Mon, 24 Feb 2025 at 08:49, Abdalla Ahmad via Tech-talk <tech-talk at aps.anl.gov> wrote:

This maybe a general question not related only to my case, but how to conditionally trigger a PV from within EPICS records? I just had an idea where I want to export or scan the waveform once I had 200 samples exactly, already in the IOC I am tracking the number of samples.

 

I would use a calcout, FLNKed in a chain fast-ai->ringbuffer->calcout, configured as a counter with an upper limit.

Once the limit is reached, the calcout processes the second array record that takes the snapshot of the ring buffer. (In the calcout, use one of the "Transition..." choices for OOPT and point the OUT to the snapshot record using PP.)

 

Cheers,
~Ralph