This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

NRF sniffer only captures some data packets, before loosing communication.

Hi,

I'm new to ble.


In order to better understand what is going on, on a packet leveI got a packet sniffer.

I found a device that uses a nordic chip, and am trying to capture it's packets now.

However I don't manage to get a reliable stream of data after connection.

As  soon as the device is connected, I receive only a few packages and don't really understand the cause of this.

Is this beceause the de sniffer, or server, is switching to another channel?

Any tips and tricks are welcome.

sniffertestshort.pcap

Parents
  • Hi

    I see that you have tagged nRF51822 in this ticket. Are you perhaps using an nRF51 series device (Dongle or DK) as the sniffer device? If you are, and the devices communicating both support Bluetooth 5 or later, it's likely that they move to communicating on the 2MBPS PHY once connected for example, which the nRF51 series device won't be able to follow in.

    Can you provide some more information on what you're using as the sniffer device. What you're using as an advertiser, and as a central scanning device here?

    It could also be that you don't actually follow the device into the connection. How to do so is described in the nRF Sniffer User guide available here.

    Best regards,

    Simon

Reply
  • Hi

    I see that you have tagged nRF51822 in this ticket. Are you perhaps using an nRF51 series device (Dongle or DK) as the sniffer device? If you are, and the devices communicating both support Bluetooth 5 or later, it's likely that they move to communicating on the 2MBPS PHY once connected for example, which the nRF51 series device won't be able to follow in.

    Can you provide some more information on what you're using as the sniffer device. What you're using as an advertiser, and as a central scanning device here?

    It could also be that you don't actually follow the device into the connection. How to do so is described in the nRF Sniffer User guide available here.

    Best regards,

    Simon

Children
  • Hi Simon,

    Thank you for the info.


    I'll check the user guide tonight, an see how far I get, I supose I need to tick the "Scan and follow devices on LE Coded PHY" in the inteface options.

    I also ordered the nrf5280 dongle so I have an officially supported device with bluetooth 5.

    The advertiser is a lezyne lamp, and from what I can see it supports the bluetooth 4.1 protocol.
    The central scanning device is my phone with the nrf connect tool. with buletooth 5.0.
    My nrf51 scanner is a bluefruit LE sniffer with bluetooth 4.0.

    Kind regards,
    warre

  • Hi again

    You shouldn't need to check the "Scan and follow devices on LE Coded PHY, as Bluetooth 4.1 devices won't support that. But give the user guide a read, and see if you can figure it out. You should be able to enter the device address in Wireshark for the device you'd like to follow into its connection.

    I would indeed recommend getting an nRF52 Dongle or DK to use for sniffing to get the full Bluetooth 5 feature set.

    Best regards,

    Simon

Related