UART DFU to nRF52840 on nRF91 DK Board using NCS SDK

[Siddharth Kachhia]

Hi, I'm working with nRF9160-DK board and NCS SDK-v1.7.0 on Windows with Visual Studio Code.

In our application, we want to implement DFU over serial between two MCUs. This nRF9160 DK board also contain nRF52840 board controller. There is UART interface between two controller.

How to update the firmware of nRF52840 from nRF9160 master ? How to transfer packages from nRF9160 to nRF52840 using SMP[Simple Management Protocol]?

Can someone explain or link some examples or suggestions of how implement it?

[Elfving]

Hey Siddhart!

That sounds like a plan!

I would recommend you to start off by taking a look at the GATT DFU SMP examples (here & here), as well as one that demonstrates how to use the UART. 

Let me know if there is anything else!

Best regards,

Elfving

[Siddharth Kachhia]

Hi Elfving,

You shared SMP over Bluetooth. Is there any sample for SMP server and client over serial?

My main work is the following:

1) Download the firmware for nrf52 from Internet. The format of this firmware will be bin file. While this firmware belongs to nrf52, it will be stored on nrf91. 

2) After storing this bin, the second step is sending the firmware to nrf52 through UART. I have achieved it for basic data like char array.

3) After taking firmware through UART, I want to update it using DFU in nRF52.

Now, I'm at the first step which is storing data on nrf91. Do you have suggestion for my work and issues?

[Elfving]

Hey again Siddhart!

Siddharth Kachhia said:

Is there any sample for SMP server and client over serial?

Sadly not, though I think studying the other examples will give you an idea of what to do. The steps you've listed sound promising. You have the right idea. 

Download the image to the 91, and either store it there in the meantime or send it directly to the 52. The 52 receives the image, and saves it in a secondary slot, and when the entire image is received it restarts and the bootloader swaps the new and the old image. 

Best regards,

Elfving