Thingy91 as a BLE5 sniffer

[bernard_01]

I would like to create an ble5 sniffer from my thingy91.
I saw that the sniffer is suitable for nrf52840 dongle and nrf52840 DK, and since thingy91 as an nrf52840 board i tried flashing it with the sniffer for nrf52840.
But, unfortunately the flash didn't worked.
Error: Task failed. One or more program tasks failed. Message: Failed, [mcuBoot] Unable to parse MCUBoot image file. Unable to parse image header: invalid magic value.

It got me thinking it might be due to the fact that it isnt specifically the DK.

So is it possible? if so what am i missing?

[Sigurd Hellesvik]

Hi,

For context, why do you want to use the Thingy91 for a sniffer, and not something else, like a nRF52840Dongle?

Regards,
Sigurd Hellesvik

[bernard_01]

Exactly!

I currently have a thingy91 for a different use and i want it to be able to be a sniffer.

[Sigurd Hellesvik]

To use the Thingy91 as a sniffer, you need to re-program the nRF52840 on the Thingy91.
For this, you need a debugger or DK. Do you have that?

[bernard_01]

yes, i have a jlink debugger

[Sigurd Hellesvik]

Nice!

The code for the dongle is not pin specific, as it uses USB to communicate.
Try to connect the debugger to the thingy:91, and and select the switch to "program nrf52". Then program the dongle code for the sniffer to the Thingy and see if that works.

With the debugger, you should be able to reprogram the original Thingy nRF52 firmware later when you want to use it for something else.

Does this make sense?

[bernard_01]

Overall, YES.

However, i tried it and it's isn't that simple.
I used the Programmer to Erase & write (since im using jlink).
but i get no prints and WireShark dosnt show me any sniffer options.

[Sigurd Hellesvik]

And you ran the extcap, right?