The Primer is not able to detect a connection, but only to be detectable or not on the bus, with the function "USB_Cable_Config", and to change the connection status without disconnecting the cable.
The Primer USB port must be initialized (in mass storage mode, or another device mode) before the connection to the PC, unless the PC will not recognize the Primer ("Unknown device connected").
UTIL_GetUsb() is a deprecated function.