Programming nRF52832 custom board using nRF52840DK via SWD

[omerBzkrt]

Hi,

I had a problem while programming my custom nRF52832 board using nRF52840DK. I am using this connection that I found in the Nordic Devzone forum. I am trying to program my custom board using nrfjprog. I can see my board when I print the nrfjprog --ids and --deviceversion but I cannot see my custom board. I try different connections that I found in the forums but this is the most reliable one for my project. 

This the connections that I applied:

Custom nRF52832 board     |    nRF52840DK

VDD                                      |    VDD_nRF

                                             |    VDD_nRF' shorted with SWDSEL (as far as I understand from the forums it is shorted because to program an external device connecting to the DK)

SWDIO                                 |    SWDIO

SWDCLK                              |    SWDCLK

GND                                     |     GND

• Are there any suggestions for that?
• Even if the connections are true, how can I understand my custom board recognised by nRF52840DK?
• How can I program my custom board using nrfjprog if the connections are provided correctly?

Thanks for your answers. Have a great day to you all.

[PaKa]

What version is the nRF52840 DK you have? The connection you have listed should work with the latest HW version (3.x.y) but won't work with older kits. If you have the large debugger chip (the big chip just above your GND line) then you need to have one additional signal that connects the "GND DETECT" pin to GND when you plug in your external target. If you have the small debugger (small QFN package) then your connection shoudl work as far as I can see.

Note: the kit will always show up as the nRF52840 DK, you can only see it is targeting the external device by seeing it has a different memory size than the nRF52840.