Issues faced while scanning BLE devices using nRF Connect app and nRF52840 dongle

[Julaila]

I am writing regarding some issues our team is facing while trying to scan BLE devices using the nRF Connect app for desktop (on Windows 11).

We downloaded the latest firmware from your website and installed it on the nRF52840 dongle. The firmware installed successfully, however when we try to start scanning under the Connection Map tab, we are getting error messages (attached).

Additionally, while analyzing the Master-Slave packet communication in Wireshark, we notice that both the red and green lights on the dongle are blinking instead of just the blue light during connection establishment between the device and application.

Communication protocol of the device from which sniffing  is BLE 5.0.

It would be great if you could look into these issues and help us troubleshoot. I have attached more details on the errors faced as well as the firmware version used. Do let us know if any additional information is needed.

[ovrebekk]

Hi Julaila

The nRF Connect for Desktop BLE application, and the Wireshark Sniffer, require different hex files to be flashed to the dongle. Have you made sure to flash the correct firmware depending on which application you are running on the PC side? 

For ease of use it would probably be best to get two dongles, and assign one to each application specifically. Then you can also use them both in parallel. 

Assuming the choice of hex file is not the issue, do you have another dongle or board to test with, or have you tried it on a different PC to see if the issue could be PC related?

Best regards
Torbjørn

[hassll]

my purpose is to sniff the ble communication between ble device and mobile application through wireshark. Could you give the step by step process.I follow nRF Sniffer for Bluetooth LE v4.1.x user guid to install these things.

[ovrebekk]

Hi 

Have you followed the installation instructions here?

Step by step instructions are provided, depending on which OS you are using. 

Best regards
Torbjørn

[hassll]

i follow these steps to set the wireshark.check image 2,it show some syntax error,in the python file containing code error??

[ovrebekk]

Hi 

Looking at the screenshot I see a lot of packets in the background. Was the sniffer working for a while, and then suddenly it stopped working and displayed this error message? 

What happens if you try to set the dongle in bootloader mode and flash it one more time. Do you still get the same error when you try to launch Wireshark?

What about the LED's on the dongle, are they still showing green and red simultaneously? 

Best regards
Torbjørn

[Julaila]

Hi,

When we stop capturing and closing Wireshark, then the error displayed. We tried many to set the dongle in bootloader mode and flash it. Then same errors remains. LED's still showing green and red simultaneously. One more problem happened that some time it stops capturing in Wireshark.

Could you please provide any tutorial or guide regarding the working and usage of this dongle for Bluetooth sniffing purpose? We have already referred the guide in Nordic website, but it was not helpful for understanding these.

[ovrebekk]

Hi

We provide a set of online courses as part of the Nordic DevAcademy, and one of the courses is dedicated to Bluetooth:
https://academy.nordicsemi.com/courses/bluetooth-low-energy-fundamentals/

Chapter 6 is related to using the sniffer specifically, but if you are new to Bluetooth I would strongly recommend going through the entire course. 

That said, neither the DevAcademy chapter nor the documentation will cover all potential error message that could occur when using the sniffer, if that is what you are looking for...

Best regards
Torbjørn

[hassll]

I used Wireshark to capture the Bluetooth Low Energy traffic between two devices. In analyzing the pcap file, I can see all the core BLE advertising, scan response, and connection packets with data.can i resend the packets using nrf52840

[ovrebekk]

Hi

You mean you want to have the sniffer send the same packets that it previously received? 

There is no mechanism to do this, no. The device will act as a passive sniffer only, it can not send anything back. 

Best regards
Torbjørn

[hassll]

ok,so there is any other ddevices that support spoofing the captured packets

[ovrebekk]

Hi

Yes, there are devices such as the Ubertooth or the Flipper Zero which are designed to allow not only sniffing of wireless signals, but also injecting packets in order to test security vulnerabilities etc. 

We haven't tested any of these devices in house though, and can't really attest to their effectiveness or ease of use. 

Best regards
Torbjørn