Parallel calls to ActiveX using Invoke Node

Dear colleagues,
Please help/advice on such a problem.
The program has a VI template (template.vit) having an ActiveX.
Two calls to this template create different instances of the ActiveX with different reference numbers.
Two asynchronous processed invokes the same function of the ActiveX supplying two different refs to Invoke Nodes. Execution of the function takes significant time.
Apparently functions of two instances are not executed asynchronously. The second waits until accomplishment of the first.
Please advice how the problem can be approached/solved. We need independency of the calls.
PS: Most of the tests were done with LabVIEW 8.6.1
Thank you

Here's a quick example. Note that for charts you should also clear the history if so desired.
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Attachments:
defaults.vi ‏25 KB

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The set control value method is the same as using a local variable or the value property - it doesn't fire the event. To fire the event, you need to use the Value(signaling) property. To do this, you need to get a reference to the control. You can do this by taking the Front Panel property of the server VI and wiring that reference into another property node. Then, you get an array of references to all the controls on the FP. You will need to find your control and wire its reference into the signaling property and then the event will fire. There are, of course, other ways of doing this - this one is fairly complicated, since you have to find the reference.
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Multiple VI instance will not RUN using invoke node

Hi,
I need to have multiple instances of the same VI running.
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Attachments:
Call_Plot Window.png ‏31 KB
Template_Plot window.png ‏23 KB

As simple as that Kumar !
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A lot of this code should be done different, just for the reason that it is difficult to find such problems. I would suggest you browse examples about state machines to see some 'best practices'.
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Reinitialize to defaults using invoke node?

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Here's a quick example. Note that for charts you should also clear the history if so desired.
LabVIEW Champion . Do more with less code and in less time .
Attachments:
defaults.vi ‏25 KB

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Hi Bichillo,
I posted an example here.
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=137&HOID=50650000000500000014570100&HTHREAD=000087828&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0
It demonstrates how to do what you are asking.
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The catch is that it is not all the time.
I am trying to set up a configuration utility which allows configuration or modification of settings of channels and serial ports. This top level VI pulls values from a configuration file using a mid-level VI which, in addition to loading the configuration file, also calls a further sub VI which initialises and sets as default front panel objects on a number of VI's using Invoke Nodes. Thus there is a heirachy of three VI's
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Go to Solution.
Attachments:
3650.vi ‏107 KB
86140B Trace_Screen Capture(2).llb ‏143 KB

deniz wrote:
I tried to implement the first method you suggested. But i had trouble since I am just a beginner. Could you please be more specific in explaining the solution? I am stating the problem again. Once the stability criterion is met I want the case structure to execute on the increments of 30 second or so. How can I do that by using shift registers? I tried to do what you suggested as in the code attached but it did not work. (I could not make the case structure dependent on two conditions)
I understood what you wanted perfectly fine. You just didn't implement it correctly. See attached. Please revisit my comment regarding the Write To Spreadsheet File that already exists inside of the "Trace Xfer" VI.
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Thus, the elapsed time VIs that are inside of the loop does not progress at 1 second increments. Is there any way to set an elapsed time that is independent of timestamp of thermocouple reading device?
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Attachments:
3650.vi ‏116 KB

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Attachments:
openvi.vi ‏38 KB
ShowChannel2.vi ‏79 KB

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parallel.zip ‏148 KB

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Parallel calls to ActiveX using Invoke Node

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