I removed the 500 ms delay you had. The VISA read will delay waiting for the next line of data. You don't wont to miss it, so do not add a delay into between reads. It is not needed to prevent hoggin the CPU. The VISA read will be the delay. I did add it to your "Don't Read" case to slow down the while loop. Also added the flush funtion to dump what the GPS sends when you are not reading.
The Read One Line VI is a stripped down version the one I use every day.
I noticed that an over all timeout check is missing. If your GPS start sending out text without a return (it get in some abnormal mode?), the VI will lock up waiting for a return that never comes. Add a time check to the Read One Line VI inside the loop to check if it is taking too long and abort if it is.
Omar
