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Labview execution halts when window is selected

Window 2000, LV 6.0.2

Clicking on the title bar of my application halts execution for what appears to be about half a second or so, which gives me time outs on my serial port communications among other things. The same thing occurs with a few of the LV examples I've tried. It is not just stopping front panel updates, the whole program actually stops running. Is there any simple way around this, by changing the application settings for example?

I've also noticed, if the windows 'update window while dragging' option is on that moving the window also largely siezes the program. The window updates beautifully, but I would prefer the program to run rather than have the front panel update. Is there any way to prioritise th
is? I've tried several of the 'execution systems' without any noticeable change.

Thanks.
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This is just an elaboration on my post above;

The problem arises if I click (and hold) the title bar, such as one might do if one was about to move the window. The pause in the program seems to arise when there is a property node in the loop. I can read a controls' value using a local variable without the problem, but cant read the value from a property node without the pause creeping in. (I want to use the property node because I have a large array of controls to read)

Any independent loops in the BD continue to run OK while the loop with the property node gets stuck.

Steve
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> The problem arises if I click (and hold) the title bar, such as one
> might do if one was about to move the window. The pause in the program
> seems to arise when there is a property node in the loop. I can read a
> controls' value using a local variable without the problem, but cant
> read the value from a property node without the pause creeping in. (I
> want to use the property node because I have a large array of controls
> to read)
>
> Any independent loops in the BD continue to run OK while the loop with
> the property node gets stuck.


What is going on here is that certain things on the block diagram must
run in the UI thread, and this is the thread that the OS pretty much
takes over doing a live drag/grow.

By avoiding the VI Server calls
in your critical loop, you can let the
other OS threads take care of the important stuff. Also be aware that
the property node is a more expensive way of reading controls compared
to locals, and terminals are the most efficient.

Greg McKaskle
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