Situations 2
：
If reboot sequence (also called bootloader) exit and work well, you could flash the
firmware without jumper the BOOT pins. This is the the state when the stock firmware
works well and you want to upgrade to the latest version.Do as following.
a:Disable “No reboot sequence”
b:
P
ower on the board by connecting USB cable. You could find the virtual COM port will
appear on the up right corner
c: Click “Flash Firmware”. First, the board will reboot into DFU mode. Then wait the ST
DFU DRIVER Automatic installation. It’s successfully installed when you see the DFU port
on the up right corner. Now flashing via DFU will proceed. After flashing the virtual COM
port will re-appear
Q:
Unable to flash firmware via DFU.
A:
Likely the correct DFU drivers are not installed. Put the board in BOOTLOADER mode
(jump boot pins, connect USB cable). Then update DFU drivers.
Here is how to update DFU drivers:
Chrome may have problems automatically installed DFU driver for ST devices in DFU
Mode on Windows.The solution is to replace the ST driver with a libusb driver.
Download and launch Zadig
a. Options -> List All Devices
b. Select STM32 Bootloader from the drop down.
c. Choose WinUSB as the replacement.
