Motors can be run many different ways; for the FRC competition, they are controlled via PWM signals from the Digital Sidecar (not through a serial port).
I suggest making sure you have the FRC version of LabVIEW installed (from a disk that came in the Kit of Parts), along with the
update. Use the
FRC NI training materials to learn how to control a motor using the WPI Robotics Library sub-vis. Start with the default project, make sure it works, and then edit.