DFU flash transport

[Lecram69]

Hello,

Im working right now on a product which saves the update file (init + app packet) on its Flash in a specified memory section. 

After "uploading" the file in the flash the product get sets in DFU mode from extern. 

My question here: How to adjust the bootloader to do the firmware update with the already saved update file from the flash?

Is it possible to do this without transport layer? Is it easier to write a new transport layer? Are there any examples? 

If its too complicated I still can work with the Serial UART DFU transport layer. Thanks!

[Jørgen Holmefjord]

Hi,

Can you elaborate a bit on how the image is stored in flash, and how the "uploading" happens? Do you mean that a separate application firmware is stored in the flash of the device at all times?

We have multiple protocols using Background DFU, where the image is received over a transport protocol in application (i.e. not running in the bootloader when receiving the image). 

If you can store the image in the same format, it should be quite simple to modify the bootloader to only enable the new image when this is desired.

Using the Serial UART transport layer will likely be easier and not require modifications to the bootloader.

Best regards,
Jørgen

[Jørgen Holmefjord]

Which SDK version are you using?

Background DFU was originally implemented for the IoT SDK, but the IoT libraries have been removed in the latest nRF5 SDK v17.x.0 releases. This have also been used by other protocols like Thread, Zigbee, and Bluetooth Mesh.

The bootloader part of Background DFU might still be present in nRF5 SDK v17.1.0, by setting NRF_BL_DFU_ALLOW_UPDATE_FROM_APP, but there is no examples showing how to receive the updates in the application, and how to trigger the activation.

[Lecram69]

Im using SDK17.1.0

Will try out background DFU. Thx! Still a better solution than creating new transport layer

[Aurele]

Hello

I'm also interested in the same feature as you. Lecram69 did you succeed an implementation of it ? I'm currently using sdk17 with a nRF52840 and a Quectel LTEM modem. On my side, the update will be done from the app : that is to say, I will retrieve the .bin + .dat file from a FTP server and store them in the nRF internal flash.
Then, I guess i need to indicate to the bootloader how to apply the new firmware (copy + erasing the old one), is there any documentation on how to proceed ?

Thank you in advance,

Best regards,