Need FOTA Support in LWM2M firmware update object using block2 coap process.

[Pankaj Jaswal]

Hi 

We searched a lot of stuff regarding FOTA update in nRF52840DK using Lwm2m and coap protocol. But we could not get help in the right direction. We could not find any stuff or documentation (explanation) regarding BACKROUND_DFU in nRF16_SDK.

We already implemented firmware object and its instance callback with existing lwm2m client example. Now we want to update the firmware over the air using lwm2m and coap protocols. Please share any kind of stuff or example you have so that we can get out from this trouble

[Edvin]

How was this zip file generated?

The nRF52840 is programmed with .hex files. They are binary files that you get when you compile an application.These must be programmed using a programmer. If you are using a Nordic nRF52840 DK there is an on board programmer, so you can use that directly (via a Micro USB cable).

There is another way of flashing the nRF52840 DK, which is via a bootloader. But in that case, the bootloader needs to be flashed using a programmer at some point. If there is no bootloader, then there is no other way to flash the nRF52840. 

If it does have a bootloader, you can generate an application image using nrfutil. This will create a .zip file, so perhaps the zip file you hold is generated that way?

If so, it depends on what type of bootloader you have how you program it to the nRF52840. If it is a BLE bootloader, then you can use BLE (nRF Connect for Desktop/mobile).

If it is a serial bootloader, you must use UART (via nrfutil), if it is a USB bootloader, you can use USB (via nrfutil). You need to know what type of bootloader that is programmed onto the nRF, and the zip file needs to be properly generated. (You can not just zip some random files and then program it via the bootloader).