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

Subject: Long string PV access in CA client.
From: "Li, Ji via Tech-talk" <tech-talk at aps.anl.gov>
To: "tech-talk at aps.anl.gov" <tech-talk at aps.anl.gov>
Date: Fri, 9 Aug 2024 18:50:30 +0000
Hi,

I have a CA client that monitors several PVs through subscription (ca_create_subscription), gets values by copying from corresponding eha.dbr fields, and puts values to some PVs. It works well with all PVs except for long string ones, as it behaves like caget command withou -S option, i.e., it can only access the first 40 characters of the PV values. For it to work properly with long strings, how do I:
  • specify a PV. Should I use pvname or pvname.VAL$? 
  • subscribe. What type and count value should be used for the function call?

  • get. Is the returned value stored in eha.dbr?
  • put. How to write a long string to a (lsi) PV?

Best,
-Ji


Replies:
Re: Long string PV access in CA client. Kasemir, Kay via Tech-talk

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