Experimental Physics and
Industrial Control System

record(ao,"ACM:TEST:AO") {

    field(DESC,"analog output record")

    field(SCAN,"Passive")

    field(PINI,"NO")

    field(PHAS,"0")

    field(EVNT,"0")

    field(DTYP,"Soft Channel")

    field(DISV,"1")

    field(SDIS,"0.000000000000000e+00")

    field(DISS,"NO_ALARM")

    field(PRIO,"LOW")

    field(FLNK,"0.000000000000000e+00")

    field(OUT,"0.000000000000000e+00")

    field(OROC,"0.0000000e+00")

    field(DOL,"0.000000000000000e+00")

    field(OMSL,"supervisory")

    field(OIF,"Full")

    field(PREC,"5")

    field(LINR,"NO CONVERSION")

    field(EGUF,"0.0000000e+00")

    field(EGUL,"0.0000000e+00")

    field(EGU,"V")

    field(DRVH,"1000.0")

    field(DRVL,"-1000.0")

    field(HOPR,"900.0")

    field(LOPR,"0.0")

    field(AOFF,"0.0000000e+00")

    field(ASLO,"0.0000000e+00")

    field(HIHI,"900.0")

    field(LOLO,"0.0")

    field(HIGH,"450.0")

    field(LOW,"0.0")

    field(HHSV,"MAJOR")

    field(LLSV,"NO_ALARM")

    field(HSV,"MINOR")

    field(LSV,"NO_ALARM")

    field(HYST,"0.000000000000000e+00")

    field(ADEL,"0.000000000000000e+00")

    field(MDEL,"0.000000000000000e+00")

    field(SIOL,"0.000000000000000e+00")

    field(SIML,"0.000000000000000e+00")

    field(SIMS,"NO_ALARM")

    field(IVOA,"Continue normally")

    field(IVOV,"0.000000000000000e+00")

}

and withcamonitor ACM:TEST:AO.{"dbnd":{"abs":1.5}}

I only get update when I put a value outside the deadband

Anton

---

From: Kasemir, Kay <kasemirk at ornl.gov>
Sent: Friday, October 1, 2021 2:08:20 PM
To: tech-talk at aps.anl.gov; Mezger Anton Christian (PSI)
Subject: Re: channel and pv deadband

 

Can you give a reproducible example?

I tried this record with `softIocPVA` from EPICS base 7.0.6:

record(ai, "number")

{

  field(INP,  "10")

  field(MDEL, "2")

  field(PINI, "YES")

}

Both `camonitor number` and `pvmonitor number` start out by displaying the current number, and from then on they reflect changes beyond the MDEL.

So as was the case before EPICS 7, the monitor starts with an initial update, both for Channel Access and PV Access.

-Kay

---

From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of Mezger Anton Christian (PSI) via Tech-talk <tech-talk at aps.anl.gov>
Sent: Friday, October 1, 2021 7:24 AM
To: tech-talk at aps.anl.gov <tech-talk at aps.anl.gov>
Subject: [EXTERNAL] channel and pv deadband

 

Hi,

When in epics7 a channel or pv is monitored with a deadband  (perhaps also in 3.15), then a value will only be given when the value exceeds the deadband. This is the expected behaviour. However in case of a display manager, no value will be displayed when monitoring values until the deadband is exceeded. This seems to me a rather special behaviour for existing display managers that rely on monitoring the values.

Perhaps I am wrong, but perhaps a first value should be send?