difference between debug (P18) in and debug out (P19)

[Cindy]

Hi

I plan to use nrf52 DK to program my device by using a connector https://www.tag-connect.com/product/tc2030-idc-nl

But should I connect it to debug in or debug out?

what's the difference between them?

Thanks,

Cindy

[awneil]

See the User Guide for details!

'Debug Out' is for when you're using the JLink on the DK to debug an external target.

[ketiljo]

https://infocenter.nordicsemi.com/topic/ug_nrf52832_dk/UG/nrf52_DK/hw_desc_intro.html

[Cindy]

I guess it means I should use debug out, but there isn't much explain about debug in, only saying use it when nrf52 DK is on battery? I dont know if I understand it right. 

[ketiljo]

Debug in is where you want to debug the nRF52832 on the DK with an external debugger. Use debug out to connect to your board.

[Cindy]

so if there are two chips on one debugger, they will both be programmed with the same firmware? what about output reading?

like,

how I can modify this instruction to read my external board?

Thanks,

Cindy