SECURED DFU USB bootloader protocol

[astella]

To the kind attention of Nordic support team,

We are going to use nRF52833 in our products, and we would like to embed in our PC side software (driver) a custom version of nrfutil that should of course be able to do firmware update using usb-serial protocol. Could you please point me out to the right documentation to do so? Are there, I don't know, kind of *DLLs that we can use from our PC based driver application?

Thank you very much for your kindness,

Best regards

[Vidar Berg]

Hello,

The message sequence charts in the "Serial" section in the DFU protocol should give a quick overview of how the DFU transfer works. I don't know of any DLLs that could be utilized, but there is an unofficial c implementation of the DFU controller on github that you may want to take a look at: https://github.com/jimmywong2003/nrf-slim-serial-uart-dfu-host-c-code 

Best regards,

Vidar

[astella]

Thank you Vidar for your kindness. Last question, if it is not much trouble. Could you please clarify to me if the protocol we are talking about is a Nordic proprietary one, or it is open protocol? And the situation is different about this aspect should we use the open usb bootloader instead?

Thank you very much,

Best regards

[Vidar Berg]

The protocol use a proprietary command set but apart from that, it's pretty standard. It uses SLIP for encoding and decoding of packets and the standard USB CDC class to transfer the packetized data.

The open bootloader uses the same USB transport. The reason it's named open is that it accepts unsigned application and Softdevice updates. This is the bootlloader the nRF52840 Dongle ships with).

Best regards,

Vidar

[astella]

Very clear Vidar, thank you for your kindness