FOTA for nrf52840 using nrf91

[Michal]

Hi,

For my POC I use nrf9160 dk. Nrf52840 is used for scanning ble devices and nrf9160 dk is used for sending data to mqtt server (very similiar to one of the examples with exception that I don't use BLE HCI but own protocol over UART). What I need right now is to be able to do FOTA update for nrf52840. I know it is not supported out of box. I am wondering what is needed to get it done. So far this is my list:

1. Install UART bootloader on nrf52840
2. Have a command from nrf91 to nrf52 to enter bootloader
3. Implement UART DFU master on nrf91
4. Modify FOTA library to detect if update is targeted for nrf52 not nrf91

Tricky part which is unkown to me - is it possible to generate FOTA update like for nrf91 but indicate in package header somehow that target plaform is nrf52?

Regards,
Michal

[Einar Thorsrud]

Hi Michal,

1. Install UART bootloader on nrf52840
2. Have a command from nrf91 to nrf52 to enter bootloader
3. Implement UART DFU master on nrf91

This makes sense.

4. Modify FOTA library to detect if update is targeted for nrf52 not nrf91

Tricky part which is unkown to me - is it possible to generate FOTA update like for nrf91 but indicate in package header somehow that target plaform is nrf52?

We do not have any code for this. However, perhaps it would be easier and cleaner to implement this completely independent of the nRF91 FOTA solution? Then you would just have to handle receiving and caching the data in your 91 app before you update the 52 firmware via UART.

Einar