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<== Date ==> <== Thread ==>

Subject: Re: generalTime/epicsTimeGetCurrent and casr questions
From: "Jemian, Pete R. via Tech-talk" <[email protected]>
To: "[email protected]" <[email protected]>
Date: Wed, 13 Mar 2019 13:10:21 +0000
Adding to Kay's list, your caQtDM (or any other EPICS client) session 
may have more than one use of this same PV.  Such as same PV displayed 
within the same screen both as slider and numerical value.  Or presented 
in two different screens.  A central registry of PV and chid within the 
CA client application is the design to follow.

Pete

On 2019-03-13 8:06 AM, Kasemir, Kay via Tech-talk wrote:
>  > Can anyone answer how edm, CSS, and PyDM handle this?
> 
> edm and CS-Studio connect once and then keep that connection.
> 
> This is useful for two reasons.
> 
> One is the performance gain respectively reduced load on network and 
> IOCs as you already mentioned.
> 
> The other is that we're in a distributed environment.
> Your display that has a text entry field or a slider might not be the 
> only tools that's writing to those PVs.
> In fact the IOC might just change the PV on its own.
> Or you write "105", but the IOC clamps the value at "100".
> This means that you always need to monitor a PV that you write.
> You move the slider or enter a new value into a text entry field
> -> Your tool writes to the PV.
> Meanwhile, the PV can be changed by somebody else
> -> Your tool needs to show that value in the text entry field, or move 
> the slider to the received value.
> 
> Thanks,
> Kay

-- 
----------------------------------------------------------
Pete R. Jemian, Ph.D.                 <[email protected]>
Beam line Controls and Data Acquisition (BC, aka BCDA)
Advanced Photon Source,    Argonne National Laboratory
Argonne, IL  60439                    630 - 252 - 3189
-----------------------------------------------------------
       Education is the one thing for which people
          are willing to pay yet not receive.
-----------------------------------------------------------



References:
generalTime/epicsTimeGetCurrent and casr questions Layne (US), William C via Tech-talk
Re: generalTime/epicsTimeGetCurrent and casr questions Mark Rivers via Tech-talk
Re: generalTime/epicsTimeGetCurrent and casr questions Johnson, Andrew N. via Tech-talk
RE: generalTime/epicsTimeGetCurrent and casr questions Mark Rivers via Tech-talk
RE: generalTime/epicsTimeGetCurrent and casr questions Mark Rivers via Tech-talk
AW: generalTime/epicsTimeGetCurrent and casr questions Brands Helge (PSI) via Tech-talk
RE: generalTime/epicsTimeGetCurrent and casr questions Mark Rivers via Tech-talk
AW: generalTime/epicsTimeGetCurrent and casr questions Brands Helge (PSI) via Tech-talk
Re: generalTime/epicsTimeGetCurrent and casr questions Mark Rivers via Tech-talk
Re: generalTime/epicsTimeGetCurrent and casr questions Kasemir, Kay via Tech-talk

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