OTA-DFU with nRF52832 as a network(ble) co-processor

Question

Hello All!
I am going to use nRF52832 as a network co-processor. I will be using UART as the interface between the main processor and nRF52832.
My question is how to go for OTA-DFU in such a scenario?
My setup will be OTA-DFU request sent over ble which will be received by nrf52832. Then how to proceed to update the main processor? 
 Please Help me! 
 Regards,
Prasad.

Hung Bui · Accepted Answer

Hi Prasad, 
 We don't have any example that work out-of-the-box with what you want to do. 
 You would need to implement your own code to replace the old application with the new image. 
 There are 2 option on how you store the new image. 
 
 
 You store the new image on the nRF52 as normal bootloader, then instead of replacing the application on nRF52 you send the image to the main MCU via UART and replace the application on that chip. 
 
 
 You use the nRF52 as pure connectivity chip, so that the image is sent via BLE then through UART to the main MCU and store there. After you finish receiving the new image, you replace the old one. 
 
 
 In both case, you will need to implement your own bootloader on your MCU.