Writing waveform to excel file in a loop based on front panel boolean switch.

[mares_wyo]

What is the easiest way to only write waveform data to a spreadsheet based on a boolean switch of the front panel.  My acquired data is being read in a while loop and then filtering is applied.  I tried a case statement, but it slows labview down until it crashes.  I attached my VI.  I want to write the data going to the "LED_data" chart only when a button is pressed in the front panel. 

Thanks,

David

[johnsold]

David,

One good way of handling this type of situation is to use parallel loops. One loop does the data acquisition. Another loop does the filtering and any other data processing. The third loop handles user interface, like updating display and waiting for button presses, and the saving to file. The data and commands are passed among the loops via queues of LV2 style globals. Look at examples of state machine architecture.

Lynn