1. For a TM4C129 with Ethernet PHY enabled and a crystal other than 24-25Mhz, the USB DFU will show up in the device manager but not download. To correct the same add a resistor of 4.89K between RBIAS and GND pin for the ROM Boot Loader to work with the USB DFU
2. Other than above for a TM4C129 and TM4C123 which has the same issue, if the CCSv6 has been installed then the drivers for the USB DFU may have been overwritten. To revert the driver, in the device manager uninstall the USB DFU driver and replace it with the stellaris_icdi_drivers from www.ti.com/.../stellaris_icdi_drivers
