nRF 52840DK debug out on board version 3.0.0 not working

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Mon, 08 Apr 2024 11:15:08 GMT

If you can program the board, debugging should generally not be an issue.

However, this is kindof a new issue you are facing here.
To help us keep DevZone tidy, could you open a new ticket for the debugging issue?

RE: nRF 52840DK debug out on board version 3.0.0 not working

eng1n88r — Thu, 04 Apr 2024 15:28:14 GMT

Thank you so much for clarifying that! I was finally able to flash target board. Documentation not being up to date didn't make it easy.

I would also really appreciate if you could point me to where I could find any information about debugging code on target board. I tried to do it via VS Code, but without success. I created build configuration optimized for debugging. I'm able to flash the board via VS Code. But when I try to debug (or attach debugger to target) I'm getting something like this:

RE: nRF 52840DK debug out on board version 3.0.0 not working

PaKa — Thu, 04 Apr 2024 06:51:16 GMT

Sorry, didn't notice the guys didn't use the same naming on all the nets. The VTG pin on the nRF52 DK is still the same as the SWD SEL functionality wise, all the DKs use the same code for the debugger so functionality will be the same for the same OBD.

We did a change in OBD (On Board Debugger aka JLINK) device between the 2.x version and the 3.x version and that changed the functionality on some of the pins. If you follow the user manuals to the letter it should still work but if you don't mount all the lines as instructed (like you did) then you can get problems with the programming of external targets.

RE: nRF 52840DK debug out on board version 3.0.0 not working

eng1n88r — Wed, 03 Apr 2024 15:58:59 GMT

Thank you for the link! The layout or P20 on DK is a bit different, and I believe there is where some confusion coming from:

There is no VTG.

RE: nRF 52840DK debug out on board version 3.0.0 not working

eng1n88r — Wed, 03 Apr 2024 15:38:46 GMT

I think I mentioned in my question that ground on both boards is linked. Sorry, maybe I was not clear enough.

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Wed, 03 Apr 2024 07:19:11 GMT

[quote user="eng1n88r"]to the Ground on the target board or on DK itself?[/quote]

When programming an external board, both boards must share Ground.
I suggest that you start by connecting the Grounds together

RE: nRF 52840DK debug out on board version 3.0.0 not working

PaKa — Wed, 03 Apr 2024 07:08:32 GMT

Check that you comply with this one (the DK user guide for the nRF52840 hasn't been updated yet). https://infocenter.nordicsemi.com/topic/ug_nrf52832_dk/UG/dk/ext_programming_support_P20.html. The nRF52840 DK has the same interface for programming external targets as the nRF52 DK.

RE: nRF 52840DK debug out on board version 3.0.0 not working

eng1n88r — Tue, 02 Apr 2024 19:31:54 GMT

I tried both variants and no success.

RE: nRF 52840DK debug out on board version 3.0.0 not working

eng1n88r — Tue, 02 Apr 2024 16:34:50 GMT

to the Ground on the target board or on DK itself?

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Tue, 02 Apr 2024 12:53:33 GMT

Did you remember to connect SWD0_SEL to Ground?

RE: nRF 52840DK debug out on board version 3.0.0 not working

eng1n88r — Tue, 02 Apr 2024 00:04:23 GMT

I'm having the similar issue.

I'm using nRF52840DK (PCA10056 3.0.0 2023.3) and XIAO nRF52840 Sense with Expansion Board as target.

On the expansion board I use first column pins (SWCLK, SWDIO, 3V3, GND) that are connected to the P20 on DK (SWDCLK, SWDIO, VDD nRF, P1.GND).

When I switch DK to ON position, XIAO and Expansion board are powering up. I'm using VSCode and I see only DK board and during flash DK board is getting flashed.

What am I doing wrong?

RE: nRF 52840DK debug out on board version 3.0.0 not working

hector77 — Mon, 08 Aug 2022 15:08:45 GMT

Dear Sigurd,

Many thanks for the clarification, we will follow your recommendation then.

Kind regards,

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Mon, 08 Aug 2022 10:54:29 GMT

[quote user="hector77"]we have an external board self-powered at 2.5V,[/quote]

This will be it then.
Our chips require the same voltage level in the debugger as in the chip.

And our nRF52840 Development Kit(DK) only supports programming devices at 3V.
So even if it worked for the 2.0.2 DK, we can not guarantee that it should work for 3.0.0.

I recommend that you acquire an external debugger which supports variable voltages to program your custom boards.
See https://www.segger.com/products/debug-probes/j-link/

Regards,
Sigurd Hellesvik

RE: nRF 52840DK debug out on board version 3.0.0 not working

hector77 — Mon, 08 Aug 2022 07:53:06 GMT

Yes we have an external board self-powered at 2.5V, not 3V3 though but this did not seem to be an issue with the previous DK.
(I have measured 2.54V on the Debug Out connector on the DK)

We use only P19 Debug Out (I was just mentioning P20 with reference to the test we tried briefly on that connector too)

Regards,

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Mon, 08 Aug 2022 07:36:27 GMT

Hi H,

We have not found out what your issue could be yet, so I will continue asking some questions, which might help us get to the bottom of this:

I assume you have external power to your custom board?

Which voltage do the custom board run at?

Just to be sure: Are you connecting your Tag Connect cable to P19 (Debug Out)?

You mentioned P20. Could you explain some more if you connect to it and how?

Regards,
Sigurd Hellesvik

RE: nRF 52840DK debug out on board version 3.0.0 not working

hector77 — Mon, 08 Aug 2022 06:15:21 GMT

Here is the picture of one of the DK.

Many thanks for your help.

RE: nRF 52840DK debug out on board version 3.0.0 not working

hector77 — Mon, 08 Aug 2022 06:10:48 GMT

Hi Sigurd,

I can confirm the signal test between the Dev Kit Debug Out pins 3, 5, 9 and the GND of the custom board is ok.

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Fri, 05 Aug 2022 13:27:14 GMT

Hi H,

In addition, could you send a picture of the nRF52840DK 3.0.0. It might be useful to have a look at it.

Regards,
Sigurd Hellesvik

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Fri, 05 Aug 2022 12:56:19 GMT

Hi H,

Can you double-check with a multi-meter that when the cable is connected, all Developement Kit GND pins (3,5 and 9) are actually connected to GND of the Custom Board?

Regards,
Sigurd Hellesvik

RE: nRF 52840DK debug out on board version 3.0.0 not working

hector77 — Thu, 04 Aug 2022 13:07:52 GMT

Hi Sigurd,

Many thanks for the reply. To connect the custom board to the Dev Kit we use Tag-Connect cables. The reference for the Cortex compatible version we use is here:

https://www.tag-connect.com/product/tc2030-ctx-nl-6-pin-no-legs-cable-with-10-pin-micro-connector-for-cortex-processors

The datasheet can be found here: https://www.tag-connect.com/wp-content/uploads/bsk-pdf-manager/TC2030-CTX_1.pdf

From the datasheets, connection between the boards is:

6pin Custom board -> Dev Kit
----------------------------------------
1 VCC -> 1 VCC
2 SWDIO -> 2 SWDIO
3 nReset -> 10 nReset
4 SWDCLK -> 4 SWDCLK
5 GND -> 3, 5, 9 GND and also GND Detect (according to Tag-Connect datasheet)
6 SWO -> 6 SWO

Best regards,

RE: nRF 52840DK debug out on board version 3.0.0 not working

Sigurd Hellesvik — Thu, 04 Aug 2022 09:18:45 GMT

Hi H,

If you want to have a closer look at the differences between version of the Developement Kit, have a look at the hardware schematics in the nRF52840DK product page -> downloads.

Can you create a simple drawing on how you have connected the custom board to the Developement Kit, so that I can double check it?

Regards,
Sigurd Hellesvik