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a pb of communication between host pc and rt pc about voltage acquisition

hello,

I'm not understanding when i use a block << wait until next ms multiple >> on the host pc in a while loop, my program didn't write the good voltage value when i modify this on the rt pc.
This problem didn't exist when i don't use this block in the loop. Why i have this problem? what is the solution for explain this ??
It is an voltage acquisition on a pc rt with a TBX -68 with NI PXI 6070E .
fIND THE TWO PROGRAMS.

Thnks for your help!!
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Hello,

You are perfroming point-by-point hardware timed acquisition with your DAQ card so the while loop for acquisition is run at the rate you specified in the sample rate control. That is to say, the value of "String" will be updated each iteration of this loop. However you write the "String" value to TCP port in the server while loop. This loop is not timmed so consequently, you write several times the same value before a new value has been available from the acquisition process.
First, you need to probe data string sent via TCP thanks to the debug mode of LabVIEW RT. Check if the string value is equal to the voltage value. I advice you to modify a little bit your code in the RT side. Retreive the index 0 of the output array of the AI Scan function and then f
ormat this numeric value into string. This method is better in time processing instead of format all the elements of the array.
Hope this help.

Matthieu Gourssies
National Instruments
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