How does DFU mode transmit data over Bluetooth

[wasdwasd0105]

Hello,

We want to develop a program that can send and update the firmware using Linux. And I found there is only a DFU demo app for android and ios. I want to know how the updater extract and send the firmware to the NRF devices. 

Thank you

[esisk]

Once you figure out how to transfer the update firmware file to the chip, if you are using NCS instead of nRF5 SDK (which is a good idea) I'd suggest taking a look at the dfu_target library DFU target — nRF Connect SDK 1.6.99 documentation (nordicsemi.com), basing the flow of calling the library outlined by fota_download.c found in <sdk-root>\nrf\subsys\net\lib\fota_download\src\fota_download.c, and using MCUBoot as your bootloader Adding a bootloader chain — nRF Connect SDK 1.6.99 documentation (nordicsemi.com) As for transferring the file via Bluetooth, I do not know much about that but it is mainly independent of the DFU process

[Vidar Berg]

Hello,

The nRF5 SDK and the nRF connect SDK have different DFU transfer protocols. Do you know what SDK your target device is based on? For the nRF5 SDK you can nRF Util. It runs on Linux. A drawback maybe is that it doesn't work with native Bluez/built-in BT HW so you will need to have an externally connected nRF52 board for BLE connectivity.

Best regards,

Vidar