Re: MEDM display of string records not updating from PCASpy/PyEpics

["keith.thorne" <kthorne@ligo-la.caltech.edu>]

Dear Mark
	
	I actually manually entered that in text text of the MEDM file (the editor would not save it), but did not seem to matter.
I will try that again, of course.

	Keith

> On Sep 12, 2017, at 2:36 PM, Mark Rivers <rivers@cars.uchicago.edu> wrote:
> 
> Hi Keith,
>  
> There is a big difference between setting the medm Format=decimal vs Format=string.
>  
> Here is a screen shot of an medm screen I just created.  The blue text widgets are both looking at the same PV, but the upper one has Format=string, the lower one has Format=decimal.  This is important with long strings, i.e. those in waveform records in a normal IOC.
>  
> <image001.png>
>  
> There is a difference in the adl file for these 2 widgets.  Note format="string" in the second one.
>  
> "text update" {
>         object {
>                 x=155
>                 y=53
>                 width=300
>                 height=20
>         }
>         monitor {
>                 chan="13BMC-PIL:netCDF1:FilePath_RBV"
>                 clr=53
>                 bclr=4
>         }
>         limits {
>         }
> }
> "text update" {
>         object {
>                 x=155
>                 y=28
>                 width=300
>                 height=20
>         }
>         monitor {
>                 chan="13BMC-PIL:netCDF1:FilePath_RBV"
>                 clr=53
>                 bclr=4
>         }
>         format="string"
>         limits {
>         }
> }
>  
>  
> Mark
>  
>  
> -----Original Message-----
> From: keith.thorne [mailto:kthorne@ligo-la.caltech.edu] 
> Sent: Tuesday, September 12, 2017 1:34 PM
> To: Mark Rivers
> Cc: EPICS mailing list
> Subject: Re: MEDM display of string records not updating from PCASpy/PyEpics
>  
> Dear Mark
>  
> The cainfo looks fine, with “Native data type: DBF_STRING” and “Request type: DBR_STRING”.  command-line caget comes backs with a string.
>  
> Of course, the MEDM text monitor says Format “decimal’.  I tried to use the MEDM editor to save it as “string" but see no change in the underlying *.adl file. 
> But according to the MEDM manual, it will always think it is a number, even for ‘string’.
>  
> These strings are typically longer than a numeric field (up to 40 characters), so I guess it puts out 00.00 as ‘exponential’ notation when there are too many characters?
>  
> So, what is the way to display string fields for a PV in MEDM?
>  
> Thanks
>             Keith
>  
> > On Sep 12, 2017, at 12:21 PM, Mark Rivers <rivers@cars.uchicago.edu> wrote:
> > 
> > Hi Keith,
> > 
> > Some questions:
> > 
> > - What does command line cainfo say about that PV?
> > - What does command line caget show for that PV?
> > - In your medm display what "Format" have you selected for the text update widget, e.g. "decimal", "string", etc.?
> > 
> > Mark
> > 
> > 
> > -----Original Message-----
> > From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov] On Behalf Of keith.thorne
> > Sent: Tuesday, September 12, 2017 11:52 AM
> > To: EPICS mailing list
> > Subject: MEDM display of string records not updating from PCASpy/PyEpics
> > 
> > Dear all
> > 
> >          We have an odd behavior here with a continuously-running MEDM display.
> > 
> > In most cases, where the EPICS IOC is running in C or similar, the MEDM displays of string variables happily update when the underlying PV is updated.
> > 
> > However, we have a simple EPICS database that is done with PCASpy. We then use a pyEpics client to regularly update records in the EPICS database using pvPut().
> > 
> > The updated numeric records all work fine.  However, the string records (when updated) appear as 00.00 or similar in the MEDM display.
> > If we open a new MEDM display, the correct value is shown.  If we slightly resize the MEDM display, it also updates.
> > 
> > Any idea what is going on?
> > Is there something in the PCASpy database record fields we need to set to make this work?
> > 
> > - Using command-line caput() we get updated values.
> > 
> > — I was going to try an MEDM->caQtDM conversion to see if we get any different behavior.
> > 
> > Thanks
> >          Keith Thorne
> > 
> > ------
> > Keith Thorne <kthorne@ligo-la.caltech.edu>
> > CDS Software Engineer
> > LIGO Livingston Laboratory
> > Livingston, LA 70754
> > Phone: (225)686-3168 Fax: (225)686-7189
> > 
>  
>  
>  
> ------
> Keith Thorne <kthorne@ligo-la.caltech.edu>
> CDS Software Engineer
> LIGO Livingston Laboratory
> Livingston, LA 70754
> Phone: (225)686-3168 Fax: (225)686-7189