One of the other most commonly used USB classes is the USB Device Firmware Upgrade, an official USB device class specification of the USB Implementers Forum. It specifies a vendor and device-independent method of updating the firmware of a USB device. The idea is to have only one vendor-independent firmware update tool as part of the operating system, which can then be downloaded into the device. In addition to firmware download, it also specifies firmware upload, i.e. loading the currently installed device firmware to the USB Host. USB DFU class offers a more versatile USB boot loader which is available in TivaWareTM for C Series. The USB Device Firmware Update (DFU) is now available in the ROM of some TM4C123x MCUs so the user can just plug-in the device and re-program the firmware. Refer to USB boot loader example provided in TivaWareTM for C Series to see how to utilize USBLib APIs in an application to upgrade the firmware using DFU class.