Experimental Physics and
Industrial Control System

"Zimoch Dirk \(PSI\) via Tech-talk" <tech-talk at aps.anl.gov> · Sat, 10 Dec 2022 09:23:47 +0000

Hi Kevin,

StreamDevice redirection works exactly like a link or a dbPut (which is what it uses). When you write into ai.VAL using a link, it will not apply ASLO. Neither will using a redirection do.

But your value is an integer (%u). Thus you can write into ai.RVAL and use „Raw Soft Channel“ in ai.DTYP and the ai will convert.

Yours
Dirk

> Am 09.12.2022 um 20:57 schrieb Kevin Peterson via Tech-talk <tech-talk at aps.anl.gov>:
> 
> I'm working with a device that returns multiple integer values in response to queries.  These values need to be scaled by 0.1 to have the correct units.
> 
> The query function in the protocol file looks like this:
> 
> getLedIntensity {
>  out "ip?";
>  in "%(\$1:LED1:intensity_RBV)u,%(\$1:LED2:intensity_RBV)u,%(\$1:LED3:intensity_RBV)u";
> }
> 
> This is how the ai records are configured:
> 
> record(ai, "$(P)$(R):LED$(N):intensity_RBV") {
>  field(DESC, "LED $(N) intensity RBV")
>  field(PREC, "1")
>  # The raw value is in tenths of a percent
>  field(LINR, "NO CONVERSION")
>  field(ASLO, "0.1")
>  field(HOPR, "100.0")
>  field(LOPR, "0.0")
> }
> 
> When the intensities are queried, the ai records have VAL fields that have not been scaled by the ASLO value.
> 
> Does the redirection-to-record feature of streamDevice circumvent the RVAL conversion for ai records?  If not, is there something obviously wrong with this approach?
> 
> This support resides in an older IOC that is using base-3.15.6 and StreamDevice 2-8-9.
> 
> Thanks ahead of time.
> 
> Kevin
> 
> -- 
> My working hours may not be your working hours. Please do not
> feel obligated to reply outside of your normal work schedule.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System