The nRF Util for nRF5 SDK tool supports Device Firmware Update (DFU)s over a
USB Communications Device Class-Abstract Control Model (USB-CDC-ACM) connection.
DFU over a serial USB connection is supported only for chips that have USB pins
(for example, nRF52840).
Note: The USB port for the interface MCU is not connected to
the USB pins on the chip. If you are using the interface MCU, you must perform a
DFU over a serial UART
connection.
Complete the following steps to perform the DFU:
-
Connect the DFU target to your computer.
If your DFU target is an nRF52840 DK, use the USB port marked nRF
USB.
-
Run nrfutil dfu usb-serial to do a full DFU procedure over a
USB CDC ACM connection.
You can see available options by entering the following
command:nrfutil dfu usb-serial --help
For example, enter the following command to perform a DFU procedure of the file
app_dfu_package.zip over COM3 at 115200 bits per
second:
nrfutil dfu usb-serial -pkg app_dfu_package.zip -p COM3 -b 115200