How do I programatically write data from a waveform graph to a measurement file?

[jmcglump]

I am acquiring 6 channels of data (3 Voltage; 3 current) using the DAQ Assistant VI. The data is displayed on two waveform graphs: voltages are on the first graph, currents are on the second graph. I have added menu rings that allows the user to alter the timescale of each graph during runtime.

I want to be able to do the following WITHOUT stopping the outermost while loop that controls the VI.

1.) Pause the graph updates.
2.) Write the data that is displayed on the graph to a measurement file.
3.) Resume the graph updates.

I have attached the VI. Any help that you can offer will be greatly appreciated!

[smercurio_fc]

I would change the architecture. At the very least to one that uses an event structure, and if you want the Rolls Royce, to a producer-consumer one. Right now you are programming the scales every time you iterate. You only need to do this when the user selects a different scale. Is the writing to a waveform file supposed to happen all the time, or is it suppose to be controlled from a front panel Boolean, like a checkbox or something?

[jmcglump]

I intend for the waveform to be written the entire time. Our application is such that we monitor the waveforms, then capture the ones of interest.

[smercurio_fc]

What do you mean by "capture the ones of interest"? Does that mean writing to file the "ones of interest"? I thought you just said that you're writing to file all the time.

[jmcglump]

Sorry about the confusion. To clarify, we are constantly monitoring the waveforms. We only want to write to file when we see a waveform of particular interest.

[Dennis_Knutson]

The simplest thing to do would be to just place your Write Measurement File inside of a case statement wired to a front pnale Boolean.