LabView dll parallel

Hi, all.
More LabView-dll issues... After searching in the forums and checking documentation, I'm not yet very clear, so I decided to post this question.
Is it possible to call an external function (using Call Library Function Node with a dll) and run two applications (LabView and the external function) in parallel?
Moreover, is it possible to exchange data between these two different loops?
I attach a chart so you can figure out better this problem.
Thank you very much,
Francisco
Attachments:
LabView-dll running in parallel.jpg ‏366 KB

Hi, all.
Dear Rolfk,
let me see if I have understood what you stated. I've attached a flowchart with the ideas: the C++ dll includes an independent thread with the calculations and the simulation loop, and different functions for certain tasks (Initialize, Communicate and Stop Thread) that control this independent thread. This functions are called from LabView via Call Library Functions Nodes. The Communicate function, the one that sends and retrieve data from the independent thread loop, is called every cycle by LabView.
The dataflow would follow this route:
Join controls --> sent parameters as arguments for Communicate function (dll) via Call Library Function Node --> send parameters inside the dll (queues, for example) to Physics Engine --> dll simulation loop --> obtain parameters from Collision detection --> send them to Communicate function (queues, for example) --> send parameteres to LabView as returning values of Communicate function --> check for alarms (Generate alarm) --> correct settings (Join controls) ...
So, does it mean that is not needed to deal with read and write problems between LabView and the dll, because the data is exchanged via a simple Library function node called every LabView execution cycle?, and that these problems only have to be treated inside the dll (between the independent thread loop, and the Communicate function)?
Thank you very much, your support is invaluable,
Francisco.
PS. Happy Thanksgiving for American people
Attachments:
LabView and dll parallel application.png ‏72 KB

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"Enrique" wrote in message
news:[email protected]..
> I see...
>
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bobby wrote:
Hello Everybody,
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Message Edited by rolfk on 07-30-2009 07:49 AM
Rolf Kalbermatter
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a division of Test & Measurement Solutions

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I was just about to post the header file of the DLL, when
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LabView dll parallel

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