Experimental Physics and
Industrial Control System

"Kasemir, Kay via Tech-talk" <tech-talk at aps.anl.gov> · Sat, 7 Aug 2021 19:35:05 +0000

Hi:

> I subsequently tried out on EPICS base version 7.0.3.1 ..
> It works fine ..
> I am suspecting the bug may be due to newer version of EPICS.

Looks like you found a problem in R7.0.6.
Take this example record, executed by softIoc:

record(calc, "test_calc")
{
    field(SCAN, "1 second")
    field(CALC, "RNDM*100")
}

$ caget -S test_calc.CALC$
test_calc.CALC$ RNDM*100

$ caput -S test_calc.CALC$ "300"
Old : test_calc.CALC$ RNDM*100
CA.Client.Exception...............................................
    Warning: "Channel write request failed"
    Context: "op=1, channel=test_calc.CALC$, type=DBR_CHAR, count=4, ctx="test_calc""
    Source File: ../oldChannelNotify.cpp line 159
    Current Time: Sat Aug 07 2021 15:27:54.755166000
..................................................................
New : test_calc.CALC$ 3NDM*100

.. and the softIoc shows this error:

Illegal field value PV: test_calc calc: Illegal CALC field
test_calc.CALC: Syntax error, unknown operator/operand in expression "3NDM*100"

So the IOC didn't receive "300" as written, it only took "3" _and_ kept the rest of the previous CALC field value.

When instead using R7.0.4.1, all works fine.
In fact the test also succeeds with softIoc from R7.0.4.1 and caget/caput from base-7.0.6.
The issue starts when using the base-7.0.6 softIoc.

-Kay

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System