Invoke Node-Value Set doesn't cause event in second controled vi

[Hummer1]

Sorry about starting a second thread after I thought the first one was solved.

However, I have two vi's...Control.vi and Responder.vi.  Responder.vi has a button which triggers an event when it is pressed (latch mode).  However, when I try to use invoke node Control.value set to manipulate the button, the value (T/F) of the button in Responder changes, but the event is not triggered.  In a property node local to Responder, there would be an option for val(sngl)...but in the invoke node or invoke property that option doesn't seem to be available.

All I really want to do is have Control.vi cause the event controlled by the button in Responder.vi run without having to rewrite Responder.

Any thoughts.

Thanks.

[TCPlomp]

Unfortunatly the answer is NO.

You cannot trigger an event for a latching boolean without actually using the boolean.

Ton

[Hummer1]

THEY SHOULD FIX THAT....!

This capability would lead to a greatly expanded capability of integrating running 'vi and simplify building large systems....

Why not....IS THERE A WORKAROUND NI?

[Ben]

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Hummer1 wrote:

THEY SHOULD FIX THAT....!

This capability would lead to a greatly expanded capability of integrating running 'vi and simplify building large systems....

Why not....IS THERE A WORKAROUND NI?

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If the boolean is set as latch action you can't do a value signaling via a property node. Attmepting to do so returns an error 1193. Explanation:

"When a boolean has latch .... cannot use the value property..."

Why?

I would have had to have been in the room at teh time but reading the value from a latch action can change its value. This is different from every other type of control.

Work-around:

Change the mechanial action of the boolean. 

Ben

Message Edited by Ben on 09-18-2009 11:42 AM

Message Edited by Ben on 09-18-2009 11:43 AM

[Hummer1]

Thanks, I was afraid that was the case.  I was here about a year ago and am recalling all this now.

I don't want to change the mechanical action of the switches, because there are tons of them in vi's that work very well...so looks like I'm back to passing flags and scanning globals and adding events to handle in the old code....what a pain....this is going to cost me a lot of time, not to mention processor power for doing the scanning.

THIS OUGHT TO GET FIXED<<<IT IS NOT A FEATURE that I am happy to pay for. 

Thanks.

[Ben · Accepted solution]

Well I am never happy to hear that someone is going to have to revisit code that has been running.

That behaviour has been there as long as property nodes have been around and I have not run across another scenario where this caused a lot of trouble.

If you have to mod your code and trigger that event would have saved the day, then how about using a user event and adding that to the event case that handle the boolean.....

Scratch that!

How about another invisable boolean that is NOt set for latch and then mod your event case to handle that boolean as well as the one you are using now?

As, always, I just trying to help,

Ben

[Hummer1]

That makes a lot of sense...all it would have to do is kick off the change value event...lot's less complicated than globals...

Thanks.  (I could even name them something snazzy like remote button 1 or remote button 2....)

I like it.

[Ben]

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Hummer1 wrote:

...

Thanks.  (I could even name them something snazzy like remote button 1 or remote button 2....)

I like it.

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Call it anything other than the "Ben Button" and add the URL for this thread in the documentation incase anyone ever has to figure out what or why...

Ben

[Hummer1]

OOPS...Well, that doesn't work either. 

you CAN use the invoke node within the vi with signaling if the mechanical action is set to other than latch...BUT, from another vi...you can still only affect the value...note the value with signaling...so ... still can't trigger and event in a remote vi...

THIS IS A PROBLEM THAT IS A PAIN TO WORK AROUND....(Hope they hear that way down there in Austin...)

Thanks anyway.

Hummer

[Ben]

It worked for me.

Attached LV 2009 code.

Open the BD of both and put both in execution highlighting mode.

Run Untitiled 5 and it will run Untitled 6.

6 will wait for an event.

5 does the value signaling and 6 sees it and both stop.

Ben

Message Edited by Ben on 09-18-2009 02:07 PM