Experimental Physics and
Industrial Control System

[email protected] · Thu, 3 Feb 2000 18:33:38 +0100 (MET)

  > I don't like to have to process the output records and cause any resulting 
  > processing just to get the current value of an output record after a reboot, 

I agree. As all our fieldbus directed outputs are terminal, i.e. there is
no resulting processing, we just didn't care.

  > We might consider one additional subtlety

Just one?

  > for those of us who use STAT and/or
  > SEVR, particularly to display value with a color rule that indicates these
  > values.  If an output record had readback but was not processed, would it affect
  > STAT and/or SEVR values.  Right now I think these are usually UDF and INVALID
  > respectively until the record is processed. 

Good point. As the record is defined after reading back the value,
UDF/INVALID is inappropriate. Would you think we need to have another
status that announces that the value has been read back and is valid, but
the record hasn't been processed yet? Or would that be too subtle a
difference to be signalled?

Ralph

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System