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Read from channels

What is the advantage of reading 25 samples each from 6 channels 10 times to get a 6x250 array , instead of reading directly 250 samples per channel to get 6x250 array of data? Sampling rate is 1000. 

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@kdm7 wrote:

What is the advantage of reading 25 samples each from 6 channels 10 times to get a 6x250 array , instead of reading directly 250 samples per channel to get 6x250 array of data? Sampling rate is 1000. 


It depends on the type of signal you read. What is the actual requirement? What is the 1000 sampling rate when you are trying to read 250 samples? 250 samples/second? Please explain

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Difference is mostly how fast a graph will update.

P
The number of requested samples does not change the sample rate.
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Okay

 

Does using "daqmx read" 10 times in one frame read the same 25 samples 10 times ( i.e again and again)? 

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@Dennis_Knutson wrote:
Difference is mostly how fast a graph will update. 

P
The number of requested samples does not change the sample rate.

Yes it is true when you read the channel with Multiple samples. But When I read the channel 1 single value (1 sample on demand) on every iteration of the loop (Lets say my loop runs at 100 Hz), then what determines my sampling rate?. I am trying to understand, please advice.

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No, each time the read is called, you get new samples.
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So can that be called a 100 Hz sampling rate? Or any other technical term to denote that?

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Because of jitter, I'd say you have an unknown sample rate.
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Dennis,

 

Okay.

 

Which method updates the graph fast? Reading 25 samples(new samples each time) 10 times or directly reading 250 samples?

Both take 0.25 seconds( if sampling rate is 1000) right? 

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@Dennis_Knutson wrote:
Because of jitter, I'd say you have an unknown sample rate.

Yes, I agree with this.

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