tdms viewer and excel showing different data

[Pluesss]

Hi there

I have a problem reading/viewing my TDMS file. My file contains 37 channels and about 7000 samples per channel.(Just this file... Later I have to expand it on much more ~150k samples per channel)

Now my problem is: If I open the TDMS file with the TDMS file viewer VI, it begins to switch channels after ~1000 samples (Channel 29-37(MM1-MM9) should always be on -32768 but after 1000 samples the channel switches their place

My analysis of switching: After ~1000 Channel 29-37(MM1-MM9) is on 11-19 after ~2000 on 30-1 after ~3000 on 12-20 and so forth...

Besides the channel switching there is a block of ~30 rows only filled with 0 every ~1000 samples

But if I open the file in Excel with the TDMS-Addin it's showing the correct data. Why is this and how can I fix the Viewer?

Hope that you understand what i try to say 🙂

I attached one of my TDMS-files as a ZIP, couldn't attach a TDMS directly.

[zaizhou.ma · Accepted solution]

It should be a TDMS component bug, not the file viewer. We will go on investigating the issue. The workaround for you is calling the 'TDMS Defragment' node to defragment this file, then it could be displayed in viewer correctly.

According to your file, I found the file was created by TDMS Advanced nodes. You set 10000 samples for one interleaved channel, but you only write 499 samples for one channel per writing. I suggest setting the sample count exactly acrrording to how many are going to write.

[Pluesss]

Thank you for your help 🙂

With the defragmentation VI at the end it works now!

I append my data every 499 samples but at the end I will get files with 10k samples(writing around 20 times). So the number I'm adding there is the amount of samples writing per time, not in total? Didn't understand, what all the variables I had to enter, exactly do;)