How to stop while loop

I can't figure out how to stop a while loop in my labview program.
When the user presses the Run arrow in the toolbar I want my program to begin reading the serial port for GPS messages. These messages should be displayed on the front panel. Currently I have this read/display in a while loop. The program is also waiting for an extrenal trigger. When that trigger arrives, I want to grab the current string from the serial port and save it and continue reading and displaying the serial/gps string. This trigger starts the other parts of the program- signal generation, recording, and saving data which need to run concurrently with the serial/gps reading/displaying. Once the AO and AI have finished and the data have been written to disk, I want the program to stop. The serial/gps messages should be updating this whole time. Only when the data are written to disk should the whole program end. This whole sequence of events should only be done once when the user preses the Run arrow.
So far I'm unable to pluck the serial string when the trigger comes in if I'm watching the serial port all the time. The program also doesn't stop when it finishes writing to disk because the read serial while loop is still running. I don't want to use a front panel stop button. The program should stop itself when the data havebeen written.
I'm really stumped on this one but I'm new to LabVIEW so I'm sure there's an easy solution to this.
Thanks for any and all help.
Attachments:
SPoleLakeChirp.vi ‏199 KB

Dennis and altenbach- Thank you both for your patience.
I was trying to do just what Dennis suggested-"As I said, setting a local variable is one way." even before posting to this forum, but I couldn't get my local variables to reflect changes made elsewhere in the program and I wasn't able to wire from them because they were writes. The critical part I was missing was how to change a local variable from a write to a read. It was staring me in the face the whole time- just right click. When I finally found it, my problems were solved.
altenbach- thank's for putting the figures together. I do understand the logic and wiring there, but I was really trying to avoid stop buttons. The program should be smart enough to figure out when to stop. And using local variables turns out to be one way of solving this. I still have some clean up to do, but I've included my current working version just so you can see how I implimented your suggestions. There's still a lot of clean up to be done, but I'm delighted to be able to watch the serial/gps messages until I'm done reading in data. At first I had this stop variable set in the final sequence frame. That didn't work because I wasn't getting to the final frame because the loop wasn't finishing. Once I placed the stop variable in the same frame as the while loop it began stopping when it should.
If you have other comments/critiques about the wiring diagram I'm earger to hear them. I'm considering the structure finished, however. It still needs cleaning up and commenting, but I'm satisfied with the functionality.
Thanks,
Peter
Attachments:
SPoleLakeChirp.vi ‏210 KB

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