nRF54L DK can't program external MCU via SWD – J-Link error (Unknown Error in DLL)

[Doris.chen]

Hello Nordic Team,

I’m trying to use the nRF54L DK to program an external MCU via SWD, but I’m encountering an error during connection. I’ve already followed this guide:

https://docs.nordicsemi.com/bundle/ug_nrf54l15_dk/page/UG/nRF54L15_DK/program_debug/program_ext_board.html

However, I’m still unable to connect to the external target via nRF Connect for Desktop – Programmer.

Here is the error log I get:

18:14:44.589	Error: Failed with exit code 1. Failed to device info one or more devices:
  * 1057763412: [Probe] Device error: Failed to write DebugPort register 2: Unknown Error in J-Link DLL (error code = -1)
  Message: Operation device-info failed
18:14:44.590	Using nrfutil device to communicate with target via JLink
18:14:45.728	Reading readback protection status for Application core
18:14:45.729	Failed "reading readback protection status for application core". 
  Error: code: 1, description: Generic, message: Batch task protection-get failed
18:14:45.892	Error: Failed with exit code 1. One or more batch tasks failed
  - [Probe] Device error: Failed to write DebugPort register 2: Unknown Error in J-Link DLL (error code = -1)

Interestingly, with the same external target, I’m able to successfully program it using an nRF54L PDK (another board), so I don’t think the issue is with the target itself.

1. Are there any extra jumpers, settings required on the nRF54L DK to enable external MCU programming?

2. Is there a known limitation when using nRF Connect Programmer with the nRF54L DK’s onboard debugger?

3. Do I need to use nrfjprog or nrfutil manually instead of the GUI?

Any help or suggestions would be appreciated.

Thank you very much!

Best regards,
Doris

[runsiv]

Hi

1. There should not be needed anything different

2. Not that i'm aware

3. You need to use nrfutil, nrfjprog is deprecated ref Important: The nRF Command Line Tools have been archived and replaced by nRF Util. No further updates will be made to the nRF Command Line Tools. Last supported operating systems are Windows 10, Linux Ubuntu 22.04, and macOS 13. The nRF Command Line Tools will remain available for download, but do not install the SEGGER J-Link version they provide if you have a newer version installed.

I suspect in your case the voltage on the target device and the DK is to big for the DK to program the device. I would recommend either using the 10 pin flat cable or using board configuration in nRF Connect for desktop and adjust the voltage closer to that of the current voltage. 

Regards

Runar

[Doris.chen]

你好，Runar，

謝謝您的回覆！

關於您消息的這部分：

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我懷疑在您的情況下，目標設備和 DK 上的電壓太大，以至於 DK 無法對設備進行編程。

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我不太確定我是否理解了。您能解釋一下「太大」是什麼意思嗎？

您指的是目標設備的電源電壓和nRF54L DK 的 VTG之間的電壓不匹配嗎？後者定義了 SWD 介面的 I/O 電平？

為了澄清起見，這是我目前的設定：

1.目標設備由外部3.3V電源供電。

2.我使用nRF Connect for Desktop 中的Board Configurator工具將nRF54L DK 的 VDD（nPM VOUT1）配置為輸出3.3 V。

3.我使用DK 上的10 針 SWD 接頭
連接到外部目標（SWDIO、SWDCLK、GND 和 VTG 都已正確連接）。 4.透過此設置，nRF54L DK

4.進入設置，nRF54L DK根本根本無法偵測到目標（程式設計師中顯示錯誤）。有趣的是，當我使用具有相同外部 3.3 V 目標設定的nRF52 DK時，可以成功偵測到目標，儘管它無法閃爍 - 這是預期的。

您能否提供更多技術細節，說明哪種電壓不匹配可能會阻止 nRF54L DK 連接？

再次感謝。

謹致問候，
多麗絲

[runsiv]

Hi

Please write it in English. I guess just from the image it might have worked on a 52dk and not on the 54?

Regards

Runar