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<== Date ==> <== Thread ==>
Subject: Re: How to access bigstring using channel access
From: Ralph Lange <[email protected]>
To: EPICS Tech-Talk <[email protected]>
Date: Thu, 15 Jan 2015 08:33:35 -0500
Hi Deeptarka,

Try appending a dollar sign to the PV name when connecting through Channel Access. The IOC takes that as a hint to represent a string field as an array of char, so that CA can transfer more chars than the fixed-size string would allow.

    caget mybigstring.VAL    -->   string (fix 39 chars)
    caget mybigstring.VAL$   -->   array of char (max EPICS_CA_MAX_ARRAY_BYTES - 1)

HTH,
~Ralph


On 15/01/2015 07:56, Deeptarka Das/TVM/TCS wrote:

Hi all,

 

I would like to know if there is some way by which channel access can be used to put and get strings of size larger than 40. I do not wish to use waveform record nor do i wish to use pvaSrv to access PVs using pvAccess. Rather I would like to use the bigstring recordtype of EPICS V4 with channel access. Is there any way it is possible by maybe changing something in epics base?

--
Thanks and Regards,
Deeptarka Das
Mailto: [email protected]



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Re: How to access bigstring using channel access Deeptarka Das/TVM/TCS
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