DFU Zephyr using USB

[MPDeveloper89]

Hello,

In my application I'm using NORA B106 and I would like to update the firmware using USB.

In my device there isn't any FTDI and I want to use the USB layer available in Zephyr.

Can you help me to understand what are the steps to implement the application?

I think that I need to : 

• Enable the usb software module using Kconfig ( I found the following example)
• Install the driver in Windows to recognize the device

Can I use Zadig?

I tried but no Virtual COM has been detected

• Flashing the software using dedicated tool.

Thank you a lot for your support.

MP

[Vidar Berg]

Hello,

Attached below is an example based on the "Hello world" sample that includes MCUBoot configured with serial recovery support over USB ACM if you want to give it a try. You should not need to install any additional USB drivers for this unless you are working on Windows 7 or older. But you will need to install 'MCUmgr', the command line tool to perform the update: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/services/device_mgmt/mcumgr.html#command-line-tool 

hello_word_w_serial_recovery_nrf53_SDKv2.2.0.zip

Otherwise, if you need to rely on the USB class, you can try the USB DFU Sample Application in Zephyr instead. 

Best regards,

Vidar

[MPDeveloper89]

Hello Vidar,

Thank you for feedback.

I load your example where I added my board:

But, during compilation I found some errors.

In prj.conf

In mcuboot.overlay

Do you know the possible root cause?

Thank.

MP

[Vidar Berg]

Hello,

Did you build the project with an older SDK version? I tested it with v2.2.0, but v2.3.0 should work too. 

Best regards,

Vidar

[MPDeveloper89]

I tried with version 1.9.

Then, I will test it with newer version (2.2.0 I think) and I back.

MP

[Vidar Berg]

Thanks for the update. Yes, this makes sense, the Kconfig symbol was not defined in SDK 1.9. 

[MPDeveloper89]

Hello,

Finally, I'm able to build using SDK 2.2.0.

Then, I back on the current task and I build  the example shared to print "Hello World" after flashing.

Based on this consideration, which software should be already uploaded in my device?

Could be  USB CDC ACM Sample Application ?

I suppose that, to perform the software update procedure , my device should be detected.

Are correct my assumptions?

Thank you again.

MP

[Vidar Berg]

Hello,

The USB interface will get enabled when the Bootloader enters the Serial recovery / DFU mode on startup. But you need a way to signal the bootloader to enter DFU mode. Otherwise, it will just proceed to boot the application as normal when you reboot the device.

Do you have a button on your Board you can use to enter DFU mode? If you do, you can assign the button by adding and editing the following Kconfig symbols in child_image/mcuboot.conf:

# Enter DFU mode if P0.23 is pulled low on startup

CONFIG_BOOT_SERIAL_DETECT_PORT="GPIO_0" 

CONFIG_BOOT_SERIAL_DETECT_PIN=23 

CONFIG_BOOT_SERIAL_DETECT_PIN_VAL=0

Here is where the bootloader decides whether to enter serial recovery mode or not:

https://github.com/nrfconnect/sdk-mcuboot/blob/main/boot/zephyr/main.c#L574