What situations result in an event structure not capturing the change of a boolean value?

[eximo]

Labview 9 x86

Windows 7  x64

I have an event structure that has been working just fine.  It has 5 cases, each triggered by a value change in various indicators.

I added another event case, I am trying to trigger the event case with the express control "Elapsed time"  I have made a case to trigger when the "Time has Elapsed" boolean value changes.  The event structure is not executing when the value changes.

Additionally, once figured out how to make this indicator trigger the event structure, I would like to make it trigger only when the value goes from 0 to 1, and not 1 to 0 

[RavensFan · Accepted solution]

Search the forums for "value change event" and "value signalling".

The event for Value change (I assume you have that on your event structure, you header bar seems to be missing some information.) is triggered only when the user enters new information into a control, or you programmatically write a new value using the Value (signalling) property node.  Just programmatically writing to a local variable, the termina, or the "value" property node doesn't do it.

For trigger in only one direction, you can put the code in the event case inside a case structure so that it only executes when it it True (or False, if that is what you need.)

Message Edited by Ravens Fan on 04-14-2010 03:03 PM

[aeastet]

I believe that if you use a property node and use the value signaling that it will cause the event to fire. Then in your event structure look to see if the new value is equal to 1. See my example

[altenbach]

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eximo wrote:

It has 5 cases, each triggered by a value change in various indicators.

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 Event structures are primarily designed to handle user actions, i.e. changes in controls, no indicators. Still, as others have said, you can programmatically trigger events using signaling value properties (value(sgnl)).

You might be better off re-architecting your application as a state machine instead. 

[tbob]

I must be losing it.  I've used Value(signaling) many times in the past.  Now I have LV2009.  I don't see this selection.  Where is it?

[elset191]

Value(Signaling) is in the property node, not the event structure.  I think you are losing it.

[RavensFan]

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tbob wrote:

I must be losing it.  I've used Value(signaling) many times in the past.  Now I have LV2009.  I don't see this selection.  Where is it?

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Value (signalling) is the property node you write to in order to fire the Value change event that you created in the dialog box you show.

Message Edited by Ravens Fan on 04-14-2010 04:42 PM

[eximo]

This is an example of the code, it still doesn't work

[Broken_Arrow]

I haven't ran your code, but try putting the Artifact Bump terminal inside the event case which looks for its change.

Message Edited by Broken Arrow on 04-14-2010 04:22 PM

[altenbach]

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eximo wrote:
This is an example of the code, it still doesn't work

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You are still writing to a terminal, not to a signaling value property. Did you read out suggestions above?