The first thing to mention is that you are not writing anything to the file. You need to give a filename (and path) at you Open File vi. Or set function to 1: Open or Create file.
The other thing is that you need to convert the decimal string (the format the timestamp was stored) to a decimal value. This is done by using the "Decimal String to Number" vi inside the Functions Palette under the String functions (string / number conversion).
The last step you may want to do is to display both start and end time in normal hours a minutes.
In sequence panel 2, use Function -> String -> String/Number Conversion -> Fract/Exp String To Number instead of String To Byte Array and Convert To Double. Converting Byte Array output to double creates an array of doubles. Date/Time output converted to double is not an array. Cannot subtract an array of doubles from a non-array double. Causes type mismatch.
I am including a Vi which writes the time stamping into a file at D:\a.txt, then as per the option pressed from the front panel menu, compares the time.
Donald, Thanks for the help but there is one thing I don't understand about the program. Why is there two displays (one in seconds and one in the date time) when a dbl front panel display is connected to the same wire?
