SECURED DFU USB bootloader protocol

RE: SECURED DFU USB bootloader protocol

astella — Wed, 06 May 2020 11:28:54 GMT

Very clear Vidar, thank you for your kindness

RE: SECURED DFU USB bootloader protocol

Vidar Berg — Wed, 06 May 2020 11:26:28 GMT

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

RE: SECURED DFU USB bootloader protocol

astella — Tue, 05 May 2020 17:13:58 GMT

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

RE: SECURED DFU USB bootloader protocol

Vidar Berg — Tue, 05 May 2020 14:22:09 GMT

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