Could you please provide some HCI logs from the phone regarding the CIS (Connected Isochronous Stream) and BIS (Broadcast Isochronous Stream) setup procedures?

RE: Could you please provide some HCI logs from the phone regarding the CIS (Connected Isochronous Stream) and BIS (Broadcast Isochronous Stream) setup procedures?

Edvin — Thu, 27 Mar 2025 23:04:35 GMT

Did you check out the nRF Sniffer for Bluetooth LE? It is a bluetooth sniffer that just requires an nRF52-series DK/dongle. It doesn't support sniffing the actual Audio packets, but it will be able to sniff the normal BLE connection between the devices. That being said, I am not sure whether the Ellisys sniffer is able to pick up the LE Audio packets either.

Another source that was recommended by our Audio team is a book called: "Introducing Bluetooth LE Audio (2nd Edition with Auracast(TM))":

https://www.bluetooth.com/bluetooth-resources/le-audio-book-v2/

The reason the sniffer (and possibly the Ellisys) doesn't support LE Audio traces, at least yet, is that the broadcast audio packets are a form of extended advertising packets that the sniffer doesn't support (it was written before this feature was released). Whether the support for this will change in the future, I am not sure.

Best regards,

Edvin

RE: Could you please provide some HCI logs from the phone regarding the CIS (Connected Isochronous Stream) and BIS (Broadcast Isochronous Stream) setup procedures?

Tommy_Li — Thu, 27 Mar 2025 01:41:37 GMT

Hi Edvin,

Thanks for your kindly reply.

I have two nRF5340 Audio DKs. and I already tested the unicast and broacast features.

For the small comany which does't have the ellisys tools, our debug methods were to anaylsys hci logs

At the same time, the document you provided is very useful.

Sincerely Regards.

Tommy

RE: Could you please provide some HCI logs from the phone regarding the CIS (Connected Isochronous Stream) and BIS (Broadcast Isochronous Stream) setup procedures?

Edvin — Wed, 26 Mar 2025 22:04:06 GMT

Hello Tommy,

I am not sure HCI logs are the proper way to start studying the workings of Audio over Bluetooth LE. If you really want to look into this, I suggest you get hold of a couple of nRF5340 Audio DKs, and try some sample applications, and see the devices working together.

If you, however, are interrested in the messages being sent on air, I asked our LE Audio team, and they recommended the message sequence charts from Bluetooth:

https://www.bluetooth.com/bluetooth-resources/low-energy-audio-incoming-call-over-media-multi-device/

But for first hand experience, two Audio DKs, and running some of our samples found in the nRF Connect SDK is probably the better way to go.

Best regards,

Edvin