[jman4747]

There isn't anything related to serial communication in the begin VI. In this case having the initialization code outside of and feeding the loop is effectively the same as having it in the begin VI. The only difference is that code in the begin VI executes before code in periodic tasks. There is also no need for a Refnum set/get VI.

The begin VI exists to help organize code that only needs to execute once and at the beginning of the program, and to ensure that code that initializes something executes before that thing is called in other VIs like periodic tasks or teleop.