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Append Waveform, keep time stamp

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Why are you configuring for multiple samples and then only reading one?
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Message 21 of 28
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That .vi is strictly an example .vi to look at the behavior of the timestamp in successive waveforms. If I change to a single read configuration, there is no change in behavior.

 

This test makes it look like some form of timestamp is coming from the device.

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Message 22 of 28
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I don't see any issues with the timestamp. And no, there is no clock on the board so the date/time comes from the pc.
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Message 23 of 28
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@Dennis_Knutson wrote:
I don't see any issues with the timestamp. And no, there is no clock on the board so the date/time comes from the pc.

Interesting. I'll assume it's the right data and time stamp, since I have nothing else to go on. Thank you for your continued help on this topic.

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Message 24 of 28
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Hi,

 

So I am trying to build different segments of a waveform with different waveform generation Vi's that contain specific durations and then appending them. But when i add them up using the append VI, it adds up the samples instead.

 

Im hoping to add up the waveform's dt's to form the final duration of my goal wfm. the reason why i did it this way was to control the duration and the amount of samples at each portion of the waveform.

 

please see my block diagram and front panel. 

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Message 25 of 28
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Where is the "append.vi"?  I don't see it in the screenshot you posted.

 

I do see an insert Array Function.  You should be using Build Array any time you are concatenating an array to the beginning or end of another array.

 

You talk about "add up waveform dt's".  When you append waveforms, you want all the waveforms to have the same dT so when you combine them, the dT of the final waveform makes sense.  I don't understand the part where you say it "adds up the samples".

 

Look for Append Waveforms.vi in the Waveforms palette.

 

Clean up your block diagram.  You have wires running behind structures and wires with unnecessary extra bends.

Then attach your actual VI.

 

Also, reread this entire thread.  I know the Append Waveforms.vi was mentioned multiple times in this thread.

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Message 26 of 28
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Hi 

I was doing some VI experiments and i disabled it. Here ill attach the VI and a screenshot of the block diagram and front panel.

 

Sorry using the dt's were misleading. what i mean is, i want to control the length of each segment {s1,s2,....,s6} then piece them all together to form one waveform with its duration being the sum of all the lengths of each segment. 

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Message 27 of 28
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Your appending method looks like it is just fine.

But you MUST have all the sampling rates be the same.  S1, S3 and S6 won't matter what the sampling rate is in terms of quality of output since they are all square waves.

 

S2 and S4, the higher the sample rate, the better the quality of the ramps.

 

You may want to show points on your waveform graph so you can see the density of your steps.  You may want to change the interpolation style as well to something that is a flat between points.  Assuming this is a waveform that is sent to a DAQ device for output, the flats will better reflect the stair stepping that occurs with the DAQ device as it makes the incremental jumps from one sample to the next.

 

 

 

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Message 28 of 28
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