What is the difference between DK board and J-link when using external debugger?

[schosdas]

Hello!

I've only used the DK board so far, so I've rarely used an external debugger.

I'm going to use a custom board later, so I'd like to learn more about how to use an external debugger.  To use an external debugger, can use  DK board's on-board debugger and J-link.

What's the difference between these two?  Which method should I use?

And the nrf connect program just uploads the hex file to the board, and the debugger is not working, right?

Thank you.

[Amanda Hsieh]

Hi, 

 The nRF52 DK supports programming and debugging nRF51 and nRF52 devices mounted on external boards. To debug an external board with SEGGER J-Link OB IF, connect to the Debug out connector (P19) with a 10-pin cable. See Debug output.

If you don't have the J-link, you can use the on-board debugger on DK. They are the same. 

-Amanda H.