VS Code: SeggerBackend jlinkarm.dll reported error at line ...

[albert_1977]

Hi all,

I recently updated all Segger JLink software using the Segger download links and updated the probe as prompted by VS Code NRF Extension. Up until about two days ago, before the updates, flashing worked very well and without issues.

Since today, I get the following errors on screen:

It seems though that the flashing does work correctly, because the firmware gets updated on an NRF52840 (u-Blox Module) custom board.

Additionally, the VS Code extension now recognises an STM32 debugger, which didn't happen up until yesterday or two days ago.

Any ideas what it may be?

Cheers,

Alberto

[albert_1977]

So, I downgraded to v8.20 which is 1 year old, that doesn't show the error message anymore.

I still get both debuggers showing in VS Code however, and each time I need to choose which one I can use:

Is there a way for the flasher to remember which one it uses by default?

Thanks for your help so far.

Cheers,

Alberto

[Benjamin]

Could you do nrfutil device list and paste the output?

[albert_1977]

No luck with "snr", I added it to the "launch.json" file but I still get the prompt to select. This happened also after I restarted VS Code with the new settings:

Cheers,

Alberto

[Benjamin]

My mistake, this is for the Debug option not the Flash option. My guess is that this comes from a new update of the extension. I will check with the team, could you share the support information as shown in the attachment?

[albert_1977]

The attached file is the output of the support information:

// IMPORTANT: The following data can contain sensitive or confidential information about your environment.
// If you do not want others to see this information, make sure to remove it before sharing the data.

// For help and support, visit Nordic Semiconductor's DevZone at https://devzone.nordicsemi.com/.

{
  "platform": {
    "os": "win32",
    "osVersion": "Windows 11 Pro",
    "osKernel": "10.0.26200",
    "vscode": "1.111.0",
    "electron": "39.6.0",
    "node": "v22.22.0",
    "appName": "Visual Studio Code",
    "appHost": "desktop"
  },
  "system": {
    "date": "2026-03-17T01:09:00.395Z",
    "vscodeRoot": "c:\\Local\\Programs\\Microsoft VS Code\\ce099c1ed2\\resources\\app",
    "nrfConnectForDesktopInstalled": true,
    "vscodeUptime": "16:27:19",
    "osUptime": "118:34:21",
    "cpu": "13th Gen Intel(R) Core(TM) i7-13700H"
  },
  "workspace": {
    "name": "ble_xxx",
    "workspaceFile": null,
    "folders": [
      "c:\\Projects\\_\\Firmware\\ble_xxx"
    ]
  },
  "sdks": [
    {
      "version": "v3.1.1",
      "path": "c:\\ncs\\v3.1.1"
    }
  ],
  "activeBuild": "/Users/Firmware/ble_xxx/build/ble_xxx",
  "apps": [
    {
      "workspace": "c:\\Projects\\_\\Firmware\\ble_xxx",
      "uri": "c:\\Projects\\_\\Firmware\\ble_xxx",
      "buildConfigurations": [
        {
          "id": "/Users/Firmware/ble_xxx/build",
          "name": "build",
          "boardId": "ble_xxx/nrf52840",
          "type": "Sysbuild",
          "isChild": false,
          "isStale": false,
          "taskBindings": {
            "build": [],
            "pristineBuild": [],
            "flash": [],
            "eraseAndFlash": []
          },
          "sdk": "c:\\ncs\\v3.1.1",
          "toolchain": "nRF Connect SDK Toolchain v3.1.1"
        },
        {
          "id": "/Users/Firmware/ble_xxx/build/ble_xxx",
          "name": "build/ble_xxx",
          "boardId": "ble_xxx/nrf52840",
          "type": "Zephyr",
          "isChild": true,
          "isStale": false,
          "taskBindings": {
            "build": [],
            "pristineBuild": [],
            "flash": [],
            "eraseAndFlash": []
          },
          "sdk": "c:\\ncs\\v3.1.1",
          "toolchain": "nRF Connect SDK Toolchain v3.1.1"
        }
      ]
    }
  ],
  "toolchains": [
    {
      "version": "3.1.1",
      "path": "c:\\ncs\\toolchains\\c1a76fddb2",
      "displayName": "nRF Connect SDK Toolchain v3.1.1",
      "compilerTools": [
        "Zephyr SDK (arm) 0.17.0",
        "Zephyr SDK (riscv) 0.17.0"
      ]
    }
  ],
  "connectedDevices": [
    {
      "serialNumber": "000603005698",
      "deviceFamily": "NRF52_FAMILY",
      "deviceName": "nRF52840",
      "deviceVersion": "NRF52840_xxAA_REV2",
      "jlinkObFirmwareVersion": "J-Link V13 compiled Feb 26 2026 08:54:38",
      "protectionStatus": "NRFDL_PROTECTION_STATUS_NONE",
      "protectionStatusCore": "NRFDL_DEVICE_CORE_APPLICATION"
    },
    {
      "serialNumber": "001E000C5553500C20393256"
    }
  ],
  "tools": {
    "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\zephyr-sdk\\arm-zephyr-eabi\\bin\\arm-zephyr-eabi-gcc.exe": "0.17.0",
    "C:\\Program Files\\SEGGER\\JLink\\JLink.exe": "8.20",
    "C:\\Program Files\\Nordic Semiconductor\\nrf-command-line-tools\\bin\\nrfjprog.exe": "10.23.2",
    "C:\\ncs\\toolchains\\c1a76fddb2\\nrfutil": "8.1.1",
    "C:\\ncs\\toolchains\\c1a76fddb2\\nrfutil\\home\\bin\\nrfutil-device.exe": "2.13.2",
    "C:\\ncs\\toolchains\\c1a76fddb2\\cmake": "3.21.0",
    "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\Scripts\\west.exe": "1.4.0",
    "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\python.exe": "3.12.4",
    "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\ninja.exe": "1.10.2",
    "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\gperf.exe": "3.1",
    "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\dtc.exe": "1.4.7",
    "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\gn.exe": "2223",
    "C:\\ncs\\toolchains\\c1a76fddb2\\mingw64\\bin\\git.exe": "git version 2.37.3.",
    "debugger (arm)": "c:\\ncs\\toolchains\\c1a76fddb2\\opt\\zephyr-sdk\\arm-zephyr-eabi\\bin\\arm-zephyr-eabi-gdb.exe",
    "debugger (riscv)": "c:\\ncs\\toolchains\\c1a76fddb2\\opt\\zephyr-sdk\\riscv64-zephyr-elf\\bin\\riscv64-zephyr-elf-gdb.exe"
  },
  "nrfutil": {
    "nrfutil-device": {
      "version": "2.17.1",
      "binPath": "c:\\.vscode\\extensions\\nordic-semiconductor.nrf-connect-2026.3.1484-win32-x64\\platform\\nrfutil\\bin\\nrfutil-device",
      "jlinkInfo": {
        "description": "This version of SEGGER J-Link is different from the J-Link version that was used to test nrfutil device commands",
        "expectedVersion": {
          "version": "JLink_V8.76",
          "versionFormat": "string"
        },
        "name": "JlinkARM",
        "version": "JLink_V8.20",
        "versionFormat": "string"
      }
    },
    "nrfutil-sdk-manager": {
      "version": "1.11.0",
      "binPath": "c:\\.vscode\\extensions\\nordic-semiconductor.nrf-connect-2026.3.1484-win32-x64\\platform\\nrfutil\\bin\\nrfutil-sdk-manager"
    }
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      "ZEPHYR_BASE": "c:\\ncs\\v3.1.1\\zephyr",
      "ZEPHYR_TOOLCHAIN_VARIANT": "zephyr",
      "ZEPHYR_SDK_INSTALL_DIR": "c:\\ncs\\toolchains\\c1a76fddb2\\opt\\zephyr-sdk",
      "PYTHONPATH": "C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin;C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\Lib;C:\\ncs\\toolchains\\c1a76fddb2\\opt\\bin\\Lib\\site-packages"
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    "inherited": {
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  },
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      "applications": [
        "${workspaceFolder}"
      ],
      "applicationOptions": {},
      "west": {
        "env": {
          "$base": "terminal"
        },
        "verbose": ""
      },
      "boardRoots": [
        "C:\\Projects\\nrf_boards"
      ],
      "taskBindings": {},
      "buildTerminal": {
        "condensedProgress": true
      },
      "debugging": {
        "flash": true,
        "bindings": {
          "${workspaceFolder}/build/ble_xxx": "Launch ble_xxx/build/ble_xxx"
        },
        "justMyCode": false,
        "focusOnNrfDebug": true
      },
      "activeAppFollowActiveEditor": true,
      "flash": {
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        "erase": false,
        "recover": false
      },
      "enableTelemetry": true,
      "thirdpartyIntegration": {},
      "toolchainManager": {
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      "toolchain": {
        "path": "${nrf-connect.toolchain:2.5.0}"
      },
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}

Some folder and naming information has been removed but that's it.

Cheers,

Alberto

[Elfving]

Hi Alberto,

Sorry about the confusion here, but Benjamin is currently OOO, so I'll take over this case for a bit. 

It seems to me that the issue in the original post was taken care of, and solved by using the recommended JLink version. Though a new issue, that you are currently discussing, is how to connect an app to a specifc device in VSC? If so, have you seen this?

Regards,

Elfving

[albert_1977]

Hi Elfving,

Thanks for your answer. That was the solution I was looking for. I just tried it and it works.

Cheers,

Alberto

[Elfving]

Glad to hear it! Let us know if there is anything else!

Regards,

Elfving