6.15. DFU Bootloader

6.15.1. Overview

dfu_bootloader example project demonstrates the USB DFU (Device Firmware Update) bootloader functionality using CherryUSB. This bootloader allows firmware updates via USB interface. It first attempts to jump to a valid application in flash, and if no valid application is found, it enters DFU mode to receive firmware updates. To build applications that loaded by the dfu/bootloader, configure HPM_BUILD_TYPE as flash_dfu or flash_sdram_dfu when generating the project.

6.15.2. Board Setting

  • Connect USB device port to PC

6.15.3. Driver Install

WinUSB driver must be installed through zadig on windows to use the Demo.

list_all_devices

After list all devices, find CherryUSB DFU Demo and install WinUSB driver.

install_driver

6.15.4. Running the example

When the project runs correctly:

  1. If a valid application exists in flash, the bootloader will jump to it and run the application

  2. If no valid application is found, the device will enumerate as a USB DFU device on the PC

  3. Users can use dfu-util or similar tools to upload new firmware via USB - use dfu-util -l to get alt number of DFU device - then use dfu-util -D ${bin_file_path} -s ${start_addr_of_bin}:leave -a ${number_alt}

Found DFU: [0483:df11] ver=0200, devnum=39, cfg=1, intf=0, path="1-3.2", alt=1, name="@Option bytes /0x00000000/01*512 g", serial="2022123456"
Found DFU: [0483:df11] ver=0200, devnum=39, cfg=1, intf=0, path="1-3.2", alt=0, name="@Internal Flash /0x80020000/1016*16Kg", serial="2022123456"

Warning: Invalid DFU suffix signature
A valid DFU suffix will be required in a future dfu-util release
Opening DFU capable USB device...
Device ID 0483:df11
Device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Interface #0 ...
Determining device status...
DFU state(2) = dfuIDLE, status(0) = No error condition is present
DFU mode device DFU version 011a
Device returned transfer size 512
DfuSe interface name: "Internal Flash "
Downloading element to address = 0x80020400, size = 56664
Erase           [=========================] 100%        56664 bytes
Erase    done.
Download        [=========================] 100%        56664 bytes
Download done.

HPMicro Cherryusb DFU Demo
@Internal Flash /0x80020000/1016*16Kg
@Option bytes /0x00000000/01*512 g

The device will appear as a USB DFU device when in DFU mode.