Flush data TDMS, programmatically saving data and retrieval

Question

Hi all,
The purpose of this LabView is to simulate a DAQ&writting-to-file scenario. The first loop creates the data, within this loop, if the user pushed the write to file toggle switch, the data will be queued and then sent to a TDMS file writing loop (second loop). Finally the last loop retrieves the saved data and displays it in the scroll bar Waveform graph.
If TDMS-OPEN VI option operation option is "open or create"; at first the program seems to work fine but if I want to run the program again, new values will be appended to the ‘first run’ values. The correct operation would be to rewrite or replace the old file and save it with new values (keep same file name). The most logical thing to do is to change the option of the TDMS OPEN to “create or replace” but this doesn’t work and the data or file is not even created.  I do not understand why this is happening.
Thanks in advance for your help
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Attachments:
Waveform with optional file writting.vi ‏30 KB

Answer 1

For the "False" case frame, it's fine to wire the case structure terminal to the while loop condition terminal, or just wire a "F" boolean constant to it, both way shuold work.
To stop the VI by clicking only one stop button, I think you should use a global STOP button for all the while loops. For example, you can wire this STOP button to the loop condition terminal of your DAQ while loop, and use two local variable copies of this STOP button in the other write and read while loop. Then all the loops are controlled by the common switch, once it is clicked, the VI will stop running.
By the way, you should configure this STOP button's properties as below dialog(Right click >> Properties), otherwise the VI might be broken because the local variable copy doesn't work.