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Waveform Graph passed as output of subvi does not refresh in the main vi

I have a subvi that collects data in batches and displays the batch in a waveform graph. Then I make this waveform graph as output and call it in the main subvi to display the graph. The problem is that in the subvi the graph refreshed at each batch and plots the batch (which is how I want it to behave) while in the main vi it does not display anything.

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You should probably attach a simplified version if your VI. Data is only returned to the calling VI via an output connector once the subVI completes. Does it?

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But I call the subvi inside a while loop in the main vi which should have given me the output of each subvi each time the loop is executed. Instead I get nothing.

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Post images of the sub-VI being called AND the sub-VI as well.


We should be able to help you once we see those screen shots.


But lacking those images, my money is on Christian's theory.



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I am attaching sceenshots of the mani and sub VI.

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Your indicator is outside the while loop, so you wont get anything until the while loop finishes!

Also your subVI is inside a case structure, the output of which is set to 'default if unwired' (which means empty array) so anytime your case structure is true, your values will be wiped. If this is intented, please excuse me.

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