Two Button dialog - Fire once

[MogaRaghu]

I have an application where I need to get many responses from the user by way of two button dialogs. I need to sense the state change of a latched DI and when it goes HIGH, display a two button dialog box for the user to interact. Since this happens inside a 100ms while loop, I need to supress the dialog box after user choice is made. Otherwise the pop up will happen repeatedly as the DI is latched in HIGH state.

While I have been able to get the functionality with a shift register ( refer attachment in LV2009), I was wondering if there was a better way to do these kind of "once-only-messages" ?

Thanks

[RavensFan]

I would just do it with a shift register.  You may be able to use some boolean logic with using the Implies boolean function.  It could possible minimize the embedded case structure, maybe even eliminate a shift register.  But I find the Implies function is not always easy to get working correctly right away, and may not be as easy to decode when you look at the VI later on.

[Broken_Arrow]

I agree with Ravens - what you have may seem like a lot of wires to do a simple task, but it's in keeping with the dataflow idea.

[altenbach]

Well, you don't really have a 100ms loop, because the dialog box stalls the loop forever, or until the dialog is completed (whatever comes first ;)).

Is this acceptable? Personally, I don't like such dialogs. They are annoyong to the operator.

Here's a simpler version that only uses one feedback node.

Message Edited by altenbach on 02-05-2010 09:06 AM

[MogaRaghu]

The version is simpler. But there is one glitch. The lamp once switched ON remains so even when the switch is toggled to the "Disable" position.

[RavensFan]

Perhaps you want something like this.

I moved the lamp indicator outside so it is always written to.  I also put a local variable for Enable Link inside the false case so that if you select no in the dialog, the switch returns to false.

Message Edited by Ravens Fan on 02-05-2010 08:47 PM

[MogaRaghu · Accepted solution]

It is not a good idea to change the state of the Digital Input which is "Read Only"

The final VI with the required modification is as below :

[Danybond]

where can i find these?

[prettypwnie]

[GerdW]

Hi Dany,

the other is a FALSE boolean constant from LabVIEW before LV2011 (or LV2010)…