What is the communication protocol of UART DFU？

[john.liu]

Hi:

I use nrf52840 for UART DFU.

sdk 17.1.0.

Use bootloader:pca10056_uart_debug

I want to know what is the communication protocol of UART DFU?

[Tim Schuerewegen]

Maybe it is the "init packet"?

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.1.0/lib_bootloader_dfu_validation.html

https://infocenter.nordicsemi.com/topic/ug_nrfutil/UG/nrfutil/nrfutil_customizing.html

[Amanda Hsieh]

Seems the figure is from the Transfer of an init packet, then Tim is correct. It's the Init packet. 

-Amanda

[Louis_263]

Hi,

did you do the firmware update with a PC or a second microcontroller?

[Amanda Hsieh]

Hi, 

You can run nrfutil dfu serial on PC to update firmware via UART. 

Regards,
Amanda

[Louis_263]

Hi Amanda,

thanks for your reply. I was looking for a C implementation of the UART DFU protocol because I want to perform a DFU of the nRF52820 with a STM32. I already implemented the bootloader for the nRF52 but now I look for the code for the host (DFU master).