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Understanding sample interval - regular timing, irregular, no timing for TDMS writing

Been searching for a while now and not able to find much on the differences between these and thoroughly explaining them.  What is the difference between regular timing, irregular timing, no timing?  Which one is best for my application? Although I might be able to answer that  once I have a good understanding of these. 



My application consists of a 9205 Analog module that I want to acquire from and write to a TDMS file using 16 differential channels from the module.  All 16 channels should all be using the same sample clock.  Sample per second to the TDMS will vary depending on user input in a text box (100-7000 samples per second to TDMS).  Test will be continuous streaming until user stops the acquisition.  One time stamp column that represents the time of all channels' samples would be nice but not absolutely necessary.  I could use it for testing though of the application to ensure that the samples interval is correct according to the user input (1000 s/S should give sample every .001 seconds in TDMS, etc).  A timestamp column could be used to verify this.  I don't require or want a time stamp column for each individual channel


I'm reading each channel and plotting data continuous to a waveform graph (each Ai channel has its own dedicated WFG, so there are 16 waveform graphs in this applicaition) I have the scaling correct and user changeable, so that works.  Now I'm at the point of just writing/streaming the scaled data to the TDMS. 


How should timing be set?  Regular, irregular, no timing?  Open to other suggestions/guidance as well as this is my first application with NI hardware/software. 


Thank you





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The timing is basically just what it sounds like. If you take a look at the TDMS Streaming shipping example, you can see that regular is based on a consistent time interval, whereas irregular is based on a random number for a time interval.


SampleIntervalMode Property


TDMS Streaming Example location:

C:\Users\Public\Documents\National Instruments\MStudioVS2012\DotNET\Examples\Tdms\Streaming\vb

Jason H
Automated Test Software R&D
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