J-link and SWD programming for nrf52

[Cindy]

Hi,

I'm developing a custom board based on nrf52. Currently, we are using Segger through J-Link to program nrf52 DK. 

As for my custom board, I left a 2x3 pinout including SWDIO, SWDCLK, SWO, GND, 3V3. if I connect it to the nrf52, I assumed the J-Link will work the same to my custom board? or there is an external L-link cable I can use?

I'm not sure if my idea is right or not, could anyone give me some suggestion on it?

Thanks,

Cindy

[Jørgen Holmefjord]

Hi Cindy,

Yes, you will be able to program the external board using the J-Link on the DK. You only need to connect SWDIO, SWDCLK, GND, and VDD on the custom board. Make sure you also connect VTG on P20 of the nRF5x DK to VDD on the custom board and make sure the custom board is powered at the same voltage level as the DK.

Best regards,
Jørgen

[Cindy]

P20? the pin TRACECLK?

[Jørgen Holmefjord]

No, P20 is the Debug output pin header.

[awneil]

Cindy said:

I left a 2x3 pinout

Would it not have been more sensible to use the standard ARM Cortex-M debug pinout?

http://infocenter.arm.com/help/topic/com.arm.doc.faqs/attached/13634/cortex_debug_connectors.pdf

https://www.segger.com/products/debug-probes/j-link/technology/interface-description/

https://www.segger.com/downloads/jlink/UM08001_JLink.pdf

Cindy said:

there is an external L-link cable I can use?

Standard cables would expect the standard pinout!

By using a non-standard pinout, you force yourself to use non-standard cables!