FOTA in external modem architecture.

[shlomots]

Hello, I have been going through the DFU and FOTA lesson in the Nordic intermediate course.
I see that there is a FOTA support for a scenario in which we want to update a nrf90/91 device directly or support if we send the firmware update through Bluetooth or uart to a nrf52 for example.
But I don't see support for a scenario in which we have an external modem which is connected by uart to a ble device, nrf52 for example.
am I missing something?
thanks in advance,
Shlomo

[Hung Bui]

Hi Shlomo, 

But I don't see support for a scenario in which we have an external modem which is connected by uart to a ble device, nrf52 for example.
am I missing something?

Could you please elaborate a little bit more on how you want to do DFU? Which device receive image and which device you want to update ? 

[shlomots]

Sorry that wasnt clear.
I have a nrf9160 connected to a nrf52840 via uart.
the nrf9160 communicates with a server.
I want to have the nrf9160 get the update for the nrf52840 from the server, transfer it to the nrf52840 via uart (not in SMP protocol) and then have thew nrf52840 put the image in the proper place on its flash memory for mcuboot to make the swap.
I cant find a sample supporting this kind of architecture.