Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Thu, 21 Sep 2017 13:26:05 -0500

Hi Iain,

On 09/21/2017 12:45 PM, Iain Marcuson wrote:
> My software queries a status value from a sensor.  I want to display the
> status as a string in my OPI.  The status values are neither sequential
> nor zero-indexed.  I tried to create an mbbi record with the *VL and *ST
> fields set to match the status string with the status value.  CSS BOY,
> however, does not display the string matching the mbbi VAL number, but
> the *ST field corresponding to the VAL number.  For example:
> 
> Field(ONVL, 129)
> Field(ONST,"Done")
> Field(THVL,1)
> Field(THST,"Clearing")
> 
> If the mbbi VAL field is 1, then CSS BOY will display "Done" as opposed
> to "Clearing".
> 
> What is the preferred way of outputting a string with such an enum?

The mbbi record type is designed to compare the *VL fields against the
RVAL field, then it sets the VAL field to the index corresponding to the
matching *VL field. The string representation of the VAL field will then
be the string in the corresponding *ST field, and the alarm severity of
the record is set from the corresponding *SV field.

How is this record connecting to your sensor? The device support for an
mbbi should be setting prec->rval (if you're providing your own device
support). If this mbbi is a soft record though (i.e. DSET is unset or
"Soft Channel" then you need to change it to be "Raw Soft Channel" — the
soft support reads an encoded index value from the INP link directly
into VAL and skips the comparisons with the *VL fields, whereas the raw
soft support reads the INP link value into RVAL and goes through the *VL
comparisons.

HTH,

- Andrew

-- 
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different than making the claim, "I don't care about freedom of
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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System