And I soon as I hit send, my email client revealed the window with:
https://epics.anl.gov/base/R3-15/7-docs/aiRecord.html
which seems to indicate that MDEL is intended only to keep the monitor from generating events less than this value.
Greg
From: Tech-talk <tech-talk-bounces at aps.anl.gov> On Behalf Of
Leblanc, Gregory via Tech-talk
Sent: Thursday, May 13, 2021 1:44 PM
To: tech-talk at aps.anl.gov
Subject: caput output
Hi folks!
I was working on the installation instructions to make them a bit more clear, and I ran across some caput behavior that I didn’t expect, but I’m not sure if that’s just because I’m not sure what to expect. I looked at the CAref.html doc
(https://epics.anl.gov/base/R3-15/7-docs/CAref.html#CommandTools) but this points to EPICS Base R3, and I didn’t know if there were any chances for R7.
Anyway, it looks to me like the MDEL field in my test.db only affects camonitor, and not caget.
Test.db:
record(ai, "temperature:water")
{
field(DESC, "Water temperature in the fish tank")
field(MDEL, "0.01")
}
Caput commands:
$ caput temperature:water 15.6
Old : temperature:water 15.5003
New : temperature:water 15.6
$ caput temperature:water 15.6001
Old : temperature:water 15.6
New : temperature:water 15.6001
$ caput temperature:water 15.61
Old : temperature:water 15.6001
New : temperature:water 15.61
$ caput temperature:water 15.62
Old : temperature:water 15.61
New : temperature:water 15.62
And from camonitor:
temperature:water 2021-05-13 13:36:04.090862 15.6
temperature:water 2021-05-13 13:36:14.587731 15.62
It looks like the MDEL only suppresses events (interrupts? Not sure of the terminology used here) from changes smaller than MDEL and doesn’t actually suppress updates to the IOC. I don’t know enough to tell if this is the intended behavior or not, and I’m
quite confident that I didn’t get all the terminology correct.
Greg
--
Gregory Leblanc
Accelerator Engineer
Edwards Accelerator Lab - Ohio University
123 University Terrace
Athens, OH 45701
leblanc at ohio.edu
M: (401) 52-OUAL1 or (401) 526-8251