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