Trying to establish a serial port connection to a local device (nRF52840DK) from the Bluetooth Low Energy App of the nRF Connect for Desktop.

[Jacek Majda]

Good day,

I want to use the Bluetooth Low Energy App of the nRF Connect for Desktop with my nRF52840DK as a local device.

After I have connected my device (nRF52840DK) to the USB port of my PC, I am getting the following message, as shown on the attached screenshot:

"Using JLink version: JLink_V7.96f

Installed JLink version does not match the provided version (V7.66a)".

What exactly shall I do in order to establish serial port connection to my local device (nRF52840DK)?

Regards,

JM

[Jacek Majda]

Hello,

When I click the "Select Device" menu in the top left corner, I see the message: "Connect a Nordic development kit to your computer".

But despite me having connected my nRF52840DK to my PC over the USB port - the above message stays on and I can't select my DK, as it is not displayed there - as shown on the attached screenshot.

It appears as if my DK is not being recognized by by the nRF Connect for Desktop Bluetooth Low Energy Standalone v4.0.4

Regards,

JM

[Edvin]

Are you using the correct USB port? The one on the short side of the DK? This one:

And is it powered on with the switch in the lower left corner?

Any lights on any on the LEDs on the DK?

And are you sure you are not using a USB charging cable (one without data lines)?

So: Make sure it is connected to the correct USB port on the kit, make sure it is powered on, and try with a different cable if it still doesn't work.

Best regards,

Edvin

[Jacek Majda]

Yes, I am using the correct USB port, on the short side of the DK.

As advised, I changed the USB cable - and this resolved my problem, as my nRF52840DK is now visible to the nRF Connect for Desktop.

So now when I click on "Select device", I can see my nRF52840DK listed in the top left corner. 

And when I click/select this device (nRF52840DK) a pop-up window comes up with the message:

 "Confirm

Device must be programmed, do you want to proceed?

"YES"   "NO"

When I click on "YES", I can see the LED on my nRF52840DK flashing once - but no info appears under "Discovered devices" - despite me knowing that there are several beacons transmitting in the vicinity of my PC.

I attach a screenshot showing the relevant page of the Bluetooth Low Energy App of the nRF Connect for Desktop.

Regards,

JM

[Edvin]

Try installing the a later version of JLink from segger.com. I am using v7.88j. Try to install this, restart your computer, and see if anything changes.

Best regards,

Edvin

[Jacek Majda]

As advised, I installed the JLink version:  v7.88j but the problem persists.

Despite me responding YES to the prompt: "Device must be programmed, do you want to proceed?" and subsequent completion of Device programming and Device setup (according to the log file) - when I try to select/click "Start Scan" under the "Discovered devices" - nothing happens.

This is despite me knowing that there are several beacons transmitting in the vicinity of my PC.

I attach the relevant log file and the screenshot of the relevant page of the Bluetooth Low Energy Tool.

Regards,

JM

2025-02-24T15_52_29.842Z-log.txt

[Edvin]

ok, I see. Try the following:

1: Eject the device by pressing the eject button in the top menu (where you selected the device in the first place)

2: If you don't have it already, please install nRF Command Line Tools (nrfjprog), and make sure it is added to your environment path (so that you can call nrfjprog from your command line interface).

3: Then, use this command:

nrfjprog --recover

(If more than one DK is connected to your computer, select the one with serial number 1050227486.)

4: Then select the DK again in nRF Connect for Desktop -> Bluetooth Low Energy. This time it should be properly programmed, and you should be able to start scanning properly.

I tried using one of the newer nRF52840 DKs just now, and I saw the same behavior as you. The issue is that the later revisions of the DK come with an nRF Chip where the readback protection is changed. This was changed after the nRF Connect for Desktop -> Bluetooth Low Energy was put in maintenance mode, which is why it is not aware of this readback protection change.

Unfortunately, this means that you may need to go through this step every time you power cycle the DK (I am not 100% sure, because I am checking this from home tonight, while the DK is in the office, so I am not able to power cycle it).

At least if the DK's flash is erased, and then the nRF is reset, you need to go through the "nrfjprog --recover" step. 

Best regards,

Edvin

[Jacek Majda]

As advised, I followed the below procedure:

1. Eject the device by pressing the eject button.

2. Open command.com and use the command: nrfjprog --recover

3. Then select the DK again in the nRF Connect for Desktop > Bluetooth Low Energy

And this approach has worked and I was able to start scanning.

Unfortunately, I need to go through this step every time when I power cycle the DK.

I was intending to use the nRF Connect for Desktop > Bluetooth Low Energy - to analyze the Beacon transmissions from the Acconeer XM126 module running the sample: example_detector_distance_ble_monitor - contained in: Acconeer SDK for XM126- version 1.8.1

However, despite detecting many beacon transmissions from other devices located in the vicinity of my PC, my nRF52840DK, acting as a local device for the nRF Connect for Desktop > Bluetooth Low Energy    did not detect the Beacon (Beacon type: nRF beacon) transmitted by the Acconeer XM126 module running the sample: example_detector_distance_ble_monitor.

This happened despite the fact that I was able to detect these beacon transmissions from the Acconeer XM126 module on my smartphone running the nRF Connect for Mobile application - with the Acconeer beacon advertising as: DA:0F:1D:D2:74:C7 and showing (under the Manufacturer data): Company Reserved ID <0xACC0>

What shall I do to be able to detect on the nRF Connect for Desktop > Bluetooth Low Energy app, with my nRF52840DK as a local device, the beacon  transmitted by Acconeer XM126 module?

Regards,

JM