Upgrade firmware via BLE between two BLE devices (nRF SoCs)

[Andrea Verdecchia]

I'm working to a project that involves two BLE devices: one is a USB/BLE device (nRF52840) used as a dongle, the other one is a BLE device (nRF52840) connected to the first one. I need to implement the DFU feature for both, and, while I can use the USB DFU Zephyr's template for my custom dongle, I'd like to manage the firmware upgrade of the BLE device through the custom dongle (that means between two nRF52840). On the web I found only examples for DFU between a BLE device and a PC/Smartphone with software utils, but nothing about two BLE devices or nRF SoCs.

Can you give me some suggestions to achieve what I want? Are there examples somewhere? Or some clear and complete documentation about the upgrade process and phases on the Soc?

[qarnet]

The closest to a somewhat working solution I've found is this: https://github.com/hellesvik-nordic/samples_for_nrf_connect_sdk/tree/main/bootloader_samples/client_smp/smp_client_ble

But be wary, you'd have to modify it by a lot to get it to work for your purpose.

Just some more general info for you. Your BLE Device will have to implement a smp server. This sample has that part: https://docs.zephyrproject.org/latest/samples/subsys/mgmt/mcumgr/smp_svr/README.html

Communication from your USB BLE Device to the BLE Device will happen via the smp protocol. Info on the protocol you'll find here: https://docs.zephyrproject.org/latest/services/device_mgmt/smp_protocol.html

To send smp commands to the BLE Device, your USB BLE Device will have to use the smp client. Here's a sample for that: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/bluetooth/central_smp_client/README.html Though that sample only implements the echo command.

The rest of the commands are present in the first link, but like I said, you'd have to modify it by quite a lot.

Hope that helps.

[Andrea Verdecchia]

Thanks qarnet