Event structures in older versions of labview?

[Newton2this1]

Can anyone tell me how to create a workaround for a 'value change' event structure in an older version of labview?  I have a student  version of LabVIEW 6i and need to create a queued buffer from each value change.  Thank you.

[James.M]

Ah, you're only one release away from the event structure. That's too bad.

You're going to have to implement a Polling loop that continuously checks the user inputs. Make sure you add a Wait function to the loop (~100ms) because that will act as your chance for the user to make changes. You can use shift register(s) to keep the previous loop's values and compare to get a bunch of Value Change booleans. If you want a specific case for the specific events, then you can group all of your Value Changes in to an array and act upon the ones that are True via a Case Structure.

The Event Structure only pulls a single event per loop and has a queue of events to handle for following loops. You might encounter multiple value changes in a single loop if the user clicks fast enough, or you trigger value changes. To avoid losing the trailing events, you should probably have a For loop within the Polling loop that handles all True values. Either that, or have a consumer loop that handles all of your events.

[Newton2this1]

Awesome, this is a great start! Thank you!

[James.M]

Good luck! FYI, I edited my post to point out an important functionality of the Event Strcture that you'll have to imitate in one way or another.

[Newton2this1]

Thank you, all comments welcome!

[crossrulz]

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@James.M wrote:

Ah, you're only one release away from the event structure. That's too bad.

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You should read that article more closely.  The Event Structure can out with 6.1.  However, it was only available in the Full version until a lot more recent version (2010?).

[GerdW]

One remark:

What about the 50$ Home edition of LabVIEW (2014?) available in the US?

[Newton2this1]

Great suggestions all! Thank you.

[James.M]

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@crossrulz wrote:

You should read that article more closely.  The Event Structure can out with 6.1.  However, it was only available in the Full version until a lot more recent version (2010?).

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I'm looking through it and I don't see anything regarding it not being included in the Full version until later. All I see is "Learn more about LabVIEW 2009" in there a few times.

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@Newton2this1 wrote:

Can anyone tell me how to create a workaround for a 'value change' event structure in an older version of labview?  I have a student  version of LabVIEW 6i and need to create a queued buffer from each value change.  Thank you.

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Looking through the article some more, they do mention a specific example of the way the UI could be coded before the Event Structure. Maybe your student version has this example that you could follow, or you can find it elsewhere:

examples/general/ uievents.llb/User InterfaceEventExample.vi

[crossrulz]

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@James.M wrote:

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@crossrulz wrote:

You should read that article more closely.  The Event Structure can out with 6.1.  However, it was only available in the Full version until a lot more recent version (2010?).

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I'm looking through it and I don't see anything regarding it not being included in the Full version until later. All I see is "Learn more about LabVIEW 2009" in there a few times.

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Ok, it was 2012: Include the event structure in all versions of LabVIEW