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wait ms timer value

What is the lowest value that can be used on the wait ms timer?  Accuracy from one target pc to another?  Deploying application to several target pc's and need to be accurate. 

 

Thanks for your help..........

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Well you can put in 1ms, but on any non-Real time operation systems you have NO guarantee that is what you are going to get.

As far as from one PC to another PC that depens on what else is running and I the user is moving other windows around, etc.

 

I have seen random delays of around 30ms on Windows.

 

Again with Windows you do not have any guarantee with the time delay.

 

 

Omar
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The lowest value is zero. (A wait of zero is not the same as no wait).
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If you are looping, a timed loop is a bit more deterministic. If this is for DAQ, use hardware timing. Also consider a realtime target such as FPGA.
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Can you explain in laymans terms the difference of the wait ms timer and the wait until next ms multiple function?  Also entering a value of 0 to each?  You've stated a no wait is not the same as a wait of 0.  The explaination in the help menu needs a more in depth terms.  I've seen code using both to setup delays.  I've also tried vi's with both and do not see the difference.

 

Thanks Knight.......

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Well yes its a test system using a USB DAQ and relay controllers. The software has evolved into something that I believe the hardware (pc, daq, and other items) cannot handle.  This is all because the customer has changed the requirments over the years.  For one instance, the application runs great on the development pc but when its deployed to the target it runs slower and performs at times strange????????? 

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@dg_lbe wrote:

For one instance, the application runs great on the development pc but when its deployed to the target it runs slower and performs at times strange????????? 


That can have many other reasons. Why do you suspect the wait statement?

 

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@dg_lbe wrote:

Can you explain in laymans terms the difference of the wait ms timer and the wait until next ms multiple function?  Also entering a value of 0 to each?  You've stated a no wait is not the same as a wait of 0.  The explaination in the help menu needs a more in depth terms.  I've seen code using both to setup delays.  I've also tried vi's with both and do not see the difference..


 

The difference between "wait" and "wait next ms multiple" Has been discussed many times.

 

Wait Until Next ms Multiple.vi explanation

what the difference between "Wait Until Next ms Multiple" and "wait"

 

The "wait next ms multiple" can typically only have a single instance per loop, otherwise you get very unpredictable timing:

 

Synchronization problems during measurements (using while loop)

 

A loop without a wait will spin many times before allowing other parallel code to have a turn (this can be a problem, especially with parallel infinite while loops on single core hardware). A 0ms wait allows a switch to other code parts.

 

Have a look at this thread and the example a few posts down.

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Can I state that when a 1000 ms wait ms multiple is used inside a loop and a sub vi inside the loop runs at 250ms.  The total loop time is 1000ms.  Using the same example with a wait ms timer the total loop time is 1250ms. 

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What could be the possible reason for a deployed application to run slow after the target pc comes out of standby mode?

 

Thanks

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