Trying to get USBComposite working on F103RB

gistfile1.txt

Attempted two ways to start USBSerial, but it never gets past the while loop

  USBComposite.clear(); // clear any plugins previously registered
  USBSerial.registerComponent(); 
  USBComposite.begin();
  while(!USBComposite)
  {
    Serial2.println("waiting");
    delay(1000);
  }
  
  
  or 
  
  USBSerial.begin();
  while(!USBSerial)
  {
    Serial2.println("waiting");
    delay(1000);
  }