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Problem when sampling and logging data using TDMS

Hello everyone,

          I am new to labview and CRIO and now using CRIO-9206 to sample data of 4 channels and record them in TDMS file, and the frequency requirement is 1kHz. I use the scan interface mode as the scan engine can update the IOs at the max frequency of 1kHz. According to what I expect, in the TDMS file there should be 5 channels, of which 4 consist the data group and the fifth one is the time stamp of this group of data, and the intervals between two adjacent stamps should be 1ms. When I checked the TDMS file that CRIO generated, I found that something goes wrong with the time stamp

 

data in tdms file.jpg

 

the intervals just won’t keep 1ms any longer from the last but three row and they become 4ms or 5ms after(the whole result not shown on the picture). Is this unexpected result related with any part of the block diagram? I attached the whole project file here and look forward to any kind of help or suggestion. Thanx a lot.

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Message 1 of 4
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well, the screenshot of the TDMS content on my post just can't be printed, I upload it again and put it below.

 

data in tdms file.jpg

 

I also got some screenshots of my vi for those who don't want to download the file.

 

sampling loop.jpg

TDMS process and logging loop.jpg

 

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Message 2 of 4
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TDMS will log the exact data that you input, thus, if the data logged is different than your expectation. You should probably check the data itself. By the way, the zip file you uploaded seems to be corrupted.

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Message 3 of 4
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thanx very much for your reply.

I think the problem may lie in the structure of the vi or the shared variable, but I am green on the programming of labview, so I want to know where gose wrong.

I am terribly sorry for not remembering to write information about the hardwares I use and the version of my LABVIEW, I downladed, unzipped and opened my zip file on another computer with 2011 LABVIEW and it's normal, so the corruption may be due to the forward-incompatibility of LABVIEW.

 

version of LABVIEW:2011

hardware information:

                controller:9024

                chassis:9115

                c module:9206 voltage module

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