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to find loop rate and step size?

What is the difference between loop rate and step size? how do i find the step size and loop rate of any vi in labview?

Regards,
KM
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Message 1 of 8
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Hi kamasani.

 

Could you provide a bit more information about what you are trying to obtain and what your application or end goal is? Loop rate and step size can be very generic terms used in different ways depending on the application.

 

The most common usage of each of these terms are from very different analysis realms (FPGA and ODEs respectively). Based on your question, are you looking for the execution time (worst case) for VI's in LabVIEW or something else?

- FCTesting
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Please find the vi attached. I am acquiring sensor data and do processing to obtain a significant parameter.

I need to find the loop rate and step size for the vi attached.

I would appreciate any help.

 

 

Regards,
KM
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Hello Kamasani,

 

The VI you provided is password-protected; without having access to the block diagram there isn't much that can be ascertained.  Based on the dependencies, it looks like there are one or more express VIs and you're using the DAQmx drivers for analog acquisition.

 

What is the step size you are referring to?  What units are these steps in?  Are you running some sort of simulation or control algorithm?

 

Tom L.
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Hello Tom, 

I have removed the password. Pl find the attachment. I need the step size in seconds. 

Regards,
KM
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Message 5 of 8
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It appears the unprotected version of the VI provided is analog input with data processing and it sounds like you are using an FFT, however what are you refering to for step size?  Do you mean the the execution time for one iteration of data or do you mean the step size of the FFT?

- FCTesting
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Hello Tom,

I need the execution time for one iteration of data running inside the while loop

Regards,
KM
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Message 7 of 8
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You can use the Tick Count VI to measure the execution time as demonstrated in these two examples:

 

http://digital.ni.com/public.nsf/allkb/6F6B9F4E149C80578625652800784764

 

https://decibel.ni.com/content/docs/DOC-23915

- FCTesting
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