== Important DFU topics / reliability == x some kind of DFU fallback / boot cycle counter ? * CRC check of image before attempting to execute it ? x Keep WDT running while in DFU or app ? USB control request for flash erase == QModem related == x new vendor/product ID for hub and SAM3s * board-specfic string descriptors * re-mapping of USB ports in EEPROM == Lower Priority == * unique serial number in iSerial? * printing of banner from generic function * board_main_top() automatically before calling main() x compile-time USB string generation * shared USB strings for DFU and runtime * version detection voltage ranges * locking of bootloader pages? * debug console command for switch-to-dfu * read CPU reset cause (and time?) via USB