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How to display more than two waveforms on a waveform chart?

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Okay, I have a question in the basics of waveform charts. I have to display four waveforms simultaneously in my program. I can display two graphs on it, but when I try to display four waveforms, I get an error :

You have two or more cluster data types wired together, but the clusters have different kinds or numbers of elements.
Cluster (unnamed), a cluster of 3 elements,
conflicts with cluster Waveform Chart, a cluster of 2 elements. 

 

Is there anyway I can change a waveform chart to a cluster of 4 elements? Because I borrowed this waveform from an example VI on waveform charts "Charts.vi", so I'm imagining it must've been programmed to be a cluster of 2 elements.

 

I hope I made my question clear.

 

Thanks in advance

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Message 1 of 10
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You just drag the cluster down to have four inputs.

 

 

 

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Message 2 of 10
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Hi,

        I did that, but I still get the error. I was just wondering if it's the kind of input I am giving ( three signals from waveform generation.vi and one from the DAQ Assistant), or if it is the waveform chart I have to work on.

 

Thank you.

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Message 3 of 10
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It's your signals, I'm sure but since you have not posted an image or the VI, I'm not sure what you have to change except it's probably the dynamic data from the DAQ Assistant. There is a 'Waveform Generation' palette but no such thing as 'Waveform Generation.vi'.

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Message 4 of 10
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Hi,

       Actually, it's the Simulate Signal vi. Sorry!

         I am working from home and don't have the vi, but I have created another similar vi and get the same error. The version is LabVIEW 8.

 

Thanks.

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Message 5 of 10
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I would not use dynamic data if my job depended on it but I think you need to use the Merge Signals instead of the Bundle function.

Message 6 of 10
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I did use merge signals and I don't get any error, but when I run the program, only one waveform is displayed-the waveform from the DAQmx system. All the rest of the signals are not visible on the chart. I don't know what the reason is, I tried using charts earlier, I had the same problem so then I used Graphs instead. Now I don't have a choice because I want the data points to appear in an array instead of instantaneously.

Sorry for the late reply.

 

Thanks for the help so far

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Message 7 of 10
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Solution
Accepted by topic author A BME

One of the problems you have is that the data coming from the DAQ assistant has a timestamp based on now which is approximately 3 billion seconds

 

The data from the simulated signals has a timestamp based on the start of the acquisition which is approximately 0 seconds.

 

So the chart has to be stretched from the beginning of LabVIEW time to now to show all the data.

 

Modify the simulated signals so that the timestamp is based on absolute time, then you should be able to see all the signals.

Message 8 of 10
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A BME,

 

Ravens Fan said it exactly.  If you use the Merge Signals VI, you need to change the Time Stamps section of the Simulate Signals' properties box to Absolute (not Relative).  When I tested your VI in this way, I was able to display all 4 signals regardless of whether a waveform chart or graph was used.  See the attached screen shot of my front panel results. I also re-attached my code, which is only slightly different than your original.

 

 

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Message 9 of 10
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That worked!!!!

Thanks a lot! I couldn't get around to change my code till today. It works!

 

@Roryrrific: I tried looking at your vi but I have LabVIEW version 8.0. So I couldn't open the file. But your suggestion  helped. Thank you!

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Message 10 of 10
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