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waveform chart problems in producer consumer program

I am trying to record data from a DAQ  using five analog channels and a DAQ express VI, while implementing a producer/consumer architecture. The code is attached. The data collection, analysis, and logging loops (seem to) work well.


The data display loop is causing me confusion - the waveform chart will not display 'correctly;, only a small portion of chart history appears, and it seems to constantly be resetting. The front panel has a waveform chart in the analysis loop solely for troubleshooting purposes - the charts in the display loop should be able to display essentially the same data.


Not sure where I am going astray here, any help would be appreciated. Thanks!

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Can you upload the VI? 


It could have to do with how you are using a notifier to send the data.

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Why are you using a Notifier (instead of a Queue)?  Why do you use Get Notifier Status instead of Wait on Notification?  If you tested it (like send the numbers 0 to 999 at 1kHz and having a "Consumer" that is a Get Notifier Status and saves the results, you might get 7 million of them, while if you used Wait on Notification, you'd get 1000.  If you want the Consumer to be "clocked" to the Producer, you need a function that waits ...


Of course, if you used Queues (which all the examples show), you'd also get 1000.


Bob Schor

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