UART DFU to nRF52840 on nRF91 DK Board using NCS SDK

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?

Related