Experimental Physics and
Industrial Control System

Marty Kraimer <[email protected]> · Mon, 01 Apr 1996 08:18:04 -0600

Andy Foster wrote:
> 
> Can anyone help me with the following:
> 
> I am trying to reset a value used in a calculation record
> from a button on a 'dm' screen. The CALC field is set to
> A+1 and the VAL field is looped back to INPA, so that continual
> processing of the calculation record gives: 1, 2, 3, 4, etc.
> 
> I want a button on a 'dm' screen such that when it is pressed, the
> above calculation starts again at 0. I thought this should be easy
> but haven't managed it yet.
> 
> I tried letting the button press put the
> value 0 into INPB and changing CALC to B*{A+1} so that,
> normally B=1 and we have as before. When the button is
> pressed, the record processes once with B=0 and then the
> whole thing starts again.
> 
> This doesn't work.
> I suppose because the above means that INPB needs to take two
> inputs (the first, a hardwired 1, the second a 0 put into B when
> the button is pressed).
> In this case, how can the calculation record know which value it is
> supposed to be using? Or am I going about this in totally the wrong way?

You can reset by writting 0 to the VAL field. Note that writting
a 0 will result in VAL=1 after next record processing.

Thus if record is XXX

INPA "XXX.VAL NPP NMS"
CALC "A+1"

Writing a 0 to XXX.VAL will reset.

Marty Kraimer

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System