Experimental Physics and
Industrial Control System

"Mark Rivers" <[email protected]> · Thu, 8 May 2008 14:54:23 -0500

I believe the application in question was using waveform records, which cannot be fed into a calc record.  They needed to switch the input link of the waveform record.

Mark

________________________________

From: [email protected] on behalf of Maren Purves
Sent: Thu 5/8/2008 2:31 PM
To: Tim Mooney
Cc: [email protected]
Subject: Re: Change input links run-time in a db

Ulrik, Tim,

my first reaction was: why do you want to do this
anyway?

Can't you just feed both channels, and a "switch",
into a calc record or some such and switch values?
Is there a good reason to actually switch the input
_channel_ rather than just the value?

Aloha,
Maren

Tim Mooney wrote:
> Dear folks,  Changing links at runtime has to be done via Channel Access.
> This is documented in the App Dev Guide (15.5 Runtime Link Modification).
> The reason isn't documented there (or at least I haven't found it) but
> anyway it's because lock sets have to be recalculated, and you can't
> do that while you're running under the protection of a lock set that's
> going to be recalculated.
>

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System