Using nrfsniffer to debug connection loss

[OwainIncus]

I am trying to use nrfsniffer to debug connection related issues.

We have a ble connection between central and peripheral and we are sending status updates to the peripheral fro the central at a rate of about 1 per second.

We have issues with the conenction and connection is regularly dropped and rebuilt. I can run this test walking arounf out side for say an hour and I regularly see the central indicating connection loss and connection being rebuilt.

If I try and trace this with wireshark and nrf52 dk I see all the packets from the first period of connection; but on the subsequent reconnections I only see the connection req/ind from the central; I do not see the complete trace of packets between the central and peripheral.

I am using wireshark 3.4.4 and nrf_sniffer_for_bluetooth_le_3.1.0_7cc811f.

We are seeing large gaps in the status update received by the peripheral and we suspect this is in actuality long periods of BLE not having a valid connection; hence we wish to see complete traces over these connect/disconnect cycles to try and debug the problems.


Or is snrfsniffer and wireshark just really not up to debugging  such problems?

[OwainIncus]

Hi Kenneth,

I have just repeated the microwave test using a new nrf52840 dongle as the sniffer.
Successfully logged until the peripheral was put into the microwave;  I see one led flashing green; another solid red.

On removing peripheral from the microwave the red led goes off and the green led is static; and wireshark is not seeing any more packets. I repeated and saw all leds off.possibleSnifferBug.pcapng

I can see my central is connected to the peripheral and working properly.

I would add to this that starting/stopping wireshark does not appear to start the dongle now; static green led; in fact wirshark appears crashed. Restarting wireshark; dongle interface is NOT seen!!! Had to unplug/plug dongle in again to get it seen from wireshark.

This looks like sniffer FW bugs. 

Could you please try and reproduce this one?

Regards,
Owain

[Kenneth]

I will see if I can get some time to recreate this. 

Can you just provide details about the pca10040 you are using for test here? E.g. version printed on the label.

Also type 'nrfjprog --version' in a command line window.

Thanks,
Kenneth

[OwainIncus]

Here details of the two cards/dongles used for these tests....

PCA10040  Sticker:: 1.2.1 2017.48 682534162 PCB: 400150    0256RUBR

PCA10059 Sticker: 1.0.0 2018.22 CC:33:61:0C:BC:84   PCB: 400250  0284RUBR

C:\Users\Owain>nrfjprog --version
nrfjprog version: 9.8.1
JLinkARM.dll version: 6.88a

C:\Users\Owain>

[Kenneth]

The command line tools were a bit old, maybe give it an update:
https://www.nordicsemi.com/Software-and-tools/Development-Tools/nRF-Command-Line-Tools/Download

Also, just write a "nrfjprog -p" afterwards, I believe this will update the j-link firmware afterwards (this should at least have an effect for the pca10040, which is the one I am using also for nRF sniffer. I haven't done testing with the pca10059, though I believe support was recently added).

Kenneth

[OwainIncus]

Have you tried the microwave test?

[Kenneth]

Sorry, haven't had time, it's on the to do list. 

Kenneth

[Kenneth]

I programmed two nRF52840-DK (pca10056) for devices under test:

\nRF5_SDK_17.0.2_d674dde\examples\ble_central\ble_app_blinky_c\hex

\nRF5_SDK_17.0.2_d674dde\examples\ble_peripheral\ble_app_blinky\hex

For nRF sniffer I used an nRF52-DK (pca10040), and I programmed it with the sniffer_nrf52dk_nrf52832_7cc811f.hex.

I then started Wireshark and choose the Nordic Blinky device from the drop down box, I were able to successfully follow several connections with the nRF sniffer (I just turned off/on the peripheral since I didn't walk to the microwave):

The blue section above is the second connection.

Some information about my setup:

Best regards,
Kenneth

[OwainIncus]

I haave wireshark 3.4.4; loaded latest nrfutils as said and latest segger. Reprogrammed dongle.
The powering peripheral on/off test as you did appears to work OK.

I do not have microwave here in work; will retest tomorrow at home.