Not able to program custom board with NRF52840 DK version 3.0.1 using P19 connector

[sne_333]

Hi All,

           Recently I ordered one NRF52840 DK and I received it with version 3.0.1. I was able to program my custom device using old DK. But with this new DK I am not able to program the custom board. I saw some tickets which stated that there have been some hardware changes in this new revision and documentation for the same is not updated yet. Can anyone please help me with this? I also see new slot SB19 along with SB47 in new DK. SB19 was not there in previous DK. Please let me know if something needs to be shorted so that I can program my device.

Thanks & Regards,

Snehal

[runsiv]

Update:
Could you test the following: 

nRF52840 DK v2.0.1 can program an external nRF chip if you connect the following pins:

SWDIO

SWCLK

GND

EXT_VDD

nRF52840 DK v3.0.0 can program an external nRF chip if you connect the following pins:

SWDIO

SWCLK

GND

SWD_0SEL

While this follows the JTAG SWD spec, customers with "simplified" programming headers might face issues when getting new DKs.

Regards

Runar

[sne_333]

For testing this combination I will have to use P20 connector right?

Regards,

Snehal

[runsiv]

Hi, 

I think that would be easiest as I presume your custom board was wired to work with the older setup. The DK will normally program its on-board chip. But if it detects a chip connected to either of its Debug Out headers (P19 or P20), it will program the external chip instead. For Boards with the old interface MCU, the detection method is to detect if voltage is connected to pin 1 (EXT_VTG). While kits with the new debugger(nRF5340DK and nRF52830DK 3.0.0), the detection method is to detect Ground at Pin 3(SWD0_SEL):

Regards

[sne_333]

I tried disconnecting the 3V cable from my JTAG connector and connected it on pin3(SWD0_SEL). Now on J flash lite tool it shows me "ERROR: Could not connect to target." . 

previously it was flashing my DK instead of custom board. Now its not connecting to DK as well as custom board.

Pls help.

[runsiv]

Hi, 

Just so that there are no misunderstandings could you provide drawing for the link between the custom board and the DK? 

Regards

Runar

[sne_333]

Here are the pics.. I am trying with P19 connector.

Regards,

Snehal

[runsiv]

Thanks for the images, but I need to know the pins on the other side. I can set the case to private if you like. However I just need a quick drawing of the pins on the custom board and how you connect them to DK. 

Regards

Runar

[sne_333]

ok the drawing is as follows:-

 

Previously the jtag was connected on P19 and it did not program the board.

According to your recommendation, I just cut the 3V wire from JTAG connector and connected it on Pin3(SWD_SEL) of P20 connector. Rest pins are connected on P19. Both the boards are powered by USB.

Regards,

Snehal