+ /* Preprocessor Checks: */\r
+ #if defined(USE_INTERNAL_SERIAL) && !(defined(USB_SERIES_6_AVR) || defined(USB_SERIES_7_AVR))\r
+ #error USE_INTERNAL_SERIAL invalid, the selected AVR model does not contain unique serial bytes.\r
+ #endif\r
+ \r
+ #if defined(USE_INTERNAL_SERIAL) && (USE_INTERNAL_SERIAL <= 1)\r
+ #error USE_INTERNAL_SERIAL must be defined to the string descriptor index chosen for the serial number descriptor.\r
+ #endif\r
+\r