Experimental Physics and
Industrial Control System

"Allison, Stephanie" <[email protected]> · Wed, 22 Apr 2009 11:23:36 -0700

Hi Pete,

I think you are right - the put callback may complete before the record is processed the 2nd time due to the severity change.   And vice-versa - once the communication is good again, you will have a bad severity on that mbbo until it is processed the 2nd time when the downstream record goes good again.

Stephanie

> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On Behalf
> Of Leicester, PJ (Pete)
> Sent: Wednesday, April 22, 2009 10:15 AM
> To: Andrew Johnson; [email protected]
> Subject: RE: back propagating error states
> 
> Thanks Andrew and Stephanie. The addition of the CP flag does work as
> far as I can see. It certainly seems ok from edm.
> 
> My one concern now is if I have a client using put callback to change
> the mbbo record will it see the error state in the mbbo record or is the
> callback complete before the SDIS MS CP updates the mbbi's error status.
> Perhaps there is a race condition here?
> 
> Pete
> 
> -----Original Message-----
> From: Andrew Johnson [mailto:[email protected]]
> Sent: 22 April 2009 16:29
> To: [email protected]
> Cc: Leicester, PJ (Pete)
> Subject: Re: back propagating error states
> 
> 
> Hi Pete,
> 
> On Wednesday 22 April 2009 09:27:57 Leicester, PJ (Pete) wrote:
> >
> > I tried linking the SDIS from the mbbo to the longout record with
> > maximise severity set. This did make the mbbo reflect the longout's
> > error state but only after being processed a second time so is far
> > from ideal.
> 
> If you were to add a CP flag to that SDIS link it would cause the mbbo
> record
> to get processed whenever the field it was pointing to changed.  I would
> 
> suggest pointing it to the SEVR field of the longout record, but make
> sure
> that you also set the mbbo.DISV field to something outside the range
> 0..3.
> 
> I'm not 100% sure this will work, but I think it should.
> 
> - Andrew
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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System