How to use DFU function in nRF52-DK

[chianglin]

My working platform is nRF52-DK, and I want to execute DFU firmware upgrade

1. How to create a Bootloader Image? Which Source-Code of SDK_15_2 is used to build the bootloader code?
2. Since I am using an older version of SEGGER Jlink, I can only use nRFGo Studio version 1.15. How do I burn Bootloader Image and SoftDevice? Is there any user guide?
3. When using DFU to upgrade an application, which firmware file is used for upgrade?

Thank you,
Chianglin

[Hung Bui]

Hi Ives, 

How old is your Jlink, we are still using the Jlink Lite from 8 years ago and having no problem. 

I would suggest you to follow my blog here on how to get started with the bootloader.