NI VeriStand

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Data Logging stops after a time


i want do log a measurement with 1MHz Clock frequency, but it stops after 0,1seconds. I think there is anywhere a border in maximum log file size, but i cannot find it anywhere. Where can i find this Setting?

The Plot looks like you can see in the annex.



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Message 1 of 8

Wait a minute .... where does the 1MHz data comes from? You are trying to run the PCL @ 1 MHz?

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Message 2 of 8

I've set this value in NIVS. Doesn't this work?

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Message 3 of 8

Nope. Few kHz is usually ok to achievable but not MHz. Most frequently the RT system runs between 100 Hz - 1 kHz while the faster tasks are usually moved out from the Real-Time (single point) domain to the FPGA which could run synchronously with the RT system but way faster. Usually it's some high-speed measurements, PWM generation, ... etc
FPGA "down-convert" the extracted information into a single points so they can be used inside the RT system execution logic.

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Message 4 of 8
I have the PXIe-6378 card, which should normally be able to record more than a few kHz, right?
And in the 0.1 seconds, she shows me as well, that 1 MHz is possible.
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Message 5 of 8

You would have to run the RT system (VeriStand primary loop) at 1Mz to record at that speed.  I have never run a system that fast.  If you are doing that you should probably be using the embedded recorder and only run a very short time.

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Message 6 of 8

No, NIVS engine cannot run at 1MHz. However if you only need to log your 1MHz measurements while you don't need to access measured values in other parts of your RT system, you can set up a waveform task instead of using these channels in synchronous Hardware-Timed Single Point (HWTSP) mode. Check out this article, it describes the difference.

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Message 7 of 8

Ok, thank you for your answers.

Anyway, it doesn't function better now. 

I now have problems with the Embedded data logger, which does not function as well, even though i installed it like NIVS writes.


The following link goes to the topic:

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Message 8 of 8