Really having problems conditioning while loop with a front pannel occurance

Hi
I was hoping somebody may be able to help me with a problem I am having running my vi so it acts on front panel occurrences.
The vi in question "test platform v" is in the vi library I attach with this message.
Basically I would like the vi to run continuously and each time I change the front panel values (which set the hardware) the updating loop stops the hardware is reset and the updating loop then continues.
I guess I need to use occurrences so that the updating loop recognizes when the front panel values have changed so the new data can be written to the hardware.
I am having trouble working out how to do this. I guess so event based code would be best - I ama having trouble implementing this.
I have simplified the code a lot to make the process of what I am trying to do easier to understand.
Hope somebody can help.
Many Thanks
Attachments:
big A 2 and tourist test platform.llb ‏1616 KB

You need a few more tricks. The answers you seek are in a very simple solution in the attached VI.
You need to understand events and using property nodes with Signal (Very Important)
Matt
www.CompleteAutomatedSolutions.com
Matthew Fitzsimons
Certified LabVIEW Architect
LabVIEW 6.1 ... 2013, LVOOP, GOOP, TestStand, DAQ, and Vison
Attachments:
genEvent.vi ‏31 KB

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Colleagues,
I just would like to post here small, but important bug (I guess this is the bug), which was found by coworker today morning. Just would like to share knowledge, and probably this will save some debugging time for you...
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Message Edited by Andrey Dmitriev on 10-16-2008 12:30 PM
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Proposal
In the vein of the Perl tradition, I'd like to see if there's any interest in solving short programming puzzles in LabVIEW. Anyone can post a problem and define the rules for solving it.
Here's a beginning/intermediate question to whet your "palette".
Description
With one user-action, how would you stop two while loops such that the ratio of their iterations is the always the same? One concrete way to visualize this situation is in taking measurements: two instruments use the same timing source to take measurements, but second divides the clock down so that it is an integer factor slower than the first. For example, if the slower instrument is four times slower, then at the end of the VI, if the slower instrument takes 100 measurements, the faster instrument has taken 400.
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Template (attached in LabVIEW 2009)
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Solved!
Go to Solution.
Attachments:
Multirate Loop Code Golf.vi ‏11 KB

Norbert_B wrote:
a) You work with an integer factor of speed. While this matches many application areas, there are still cases where the factor has to be floating point (e.g. 2.5). Additionally, the factor might "invert", so the master loop runs slower than the slave (factor 0.5 for instance).
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Norbert_B wrote:
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Once inside the while loop, however, none of the button are responsive within the front panel. The VI continues to run, and only 60% of my CPU is being consumed, but none of the button or scroll bars work. The only way for me to terminate the program is with the "Abort" button next to the "Run" button. If I remove the event structure so that the while loop in question runs as soon as the program starts, the front panel remains responsive. I've inserted probes within the while loop and verified that it is not running prior to the "Activate" button being asserted, and it is running after the assertion of the "Activate" button with the expected polling frequency set by the "wait till next ms multiple" vi.
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Ok. I had a chance to take a look at your code and I think you don't quite understand the concept of "dataflow". Let me see if I can help.
First of all...when I refer to your upper structure, I am referring to the first while loop, sequence structure, and subsequent while loops. When I refer to your lower structure, I am referring to the while loop containing the event structure. Just so we get our terminology straight.
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Your program starts. The first while loop executes in parallel with the loop which contains the event structure.
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Really having problems conditioni​ng while loop with a front pannel occurance

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