CYW20819 - SCO over HCI

[amorniroli]

Hi,

we just received CYBT-213043-EVAL to evaluate  the CYW20819 chipset.

I'm using the board with external BT stack (https://bluekitchen-gmbh.com/) and external MCU host and everything seems to work fine (I pull CTS high when power/reset the EVB, in order to let the chipset enter in HCI mode).

I'm also enabling SCO_Routing to transport level (using command Write_SCO_PCM_Int_Param -> [0E 04 ]: 01 1C FC 00

Something is not working as expected: SCO audio channel is established correctly, but SCO data start to be received after about 4seconds, and they are received not as SCO packet but as vendor specific events.

e.g. 

[00:00:24.408] EVT <= FF F4 1B 03 01 ED FF 13 00 00 00 ED 00 E0 41 C2 0F 41 04 ED 00 E0 02 00 41 00 08 ED 00 E0 00 00 00 00 0C ED 00 E0 00 00 05 FA 10 ED 00 E0 00 00 00 00 14 ED 00 E0 00 02 00 00 18 ED 00 E0 00 00 00 00 24 ED 00 E0 00 00 07 00 28 ED 00 E0 00 00 00 00 2C ED 00 E0 00 00 00 00 30 ED 00 E0 00 00 00 00 34 ED 00 E0 34 ED 00 E0 38 ED 00 E0 38 ED 00 E0 3C ED 00 E0 00 00 00 00 00 E1 00 E0 0F FC 4F 00 04 E1 00 E0 00 00 00 04 00 E2 00 E0 01 7C 64 00 04 E2 00 E0 00 00 00 00 C0 00 32 00 24 00 08 00 78 13 30 02 72 D6 2C EA DC A4 4E 0C 7E 89 B0 44 CF 01 CD 68 C3 32 59 80 8E 0F 01 BB 3C CA 6D 4A 15 0A 06 A0 80 08 04 DD 33 9B C1 2E 08 92 29 74 93 E1 DA A7 36 21 4C 05 0E 91 04 EF 41 BF 5E 90 44 53 08 15 15 D2 05 C1 75 4D F1 E4 6B B2 1F 3C 1C 34 09 C1

After 8seconds, I'm not receiving anything else.

Questions:

1) where can I download HCI vendor specific command list for CYW20819?
2) why the CYW20819 stops to route SCO packets over HCI after about 8seconds?

Thank you for the support.

Best regards,

Alessandro Morniroli

[amorniroli]

Hi,

point 2) may be because I'm not sending any SCO packets right now (I just want to receive them for now);

point 1) I meant HCI vendor specific events list, not commands. I tried to open SCO channel on two different headsets and the same first packet was received: I'm not able to decode it. 

[00:00:08.603] EVT <= FF F4 1B 03 2C 1A 01 00 00 00 90 00 00 00 00 01 00 C0 00 00 20 00 00 80 02 00 0A 00 00 00 00 00 00 00 09 00 10 09 31 01 0C 22 00 00 27 00 00 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Is SCO over HCI possible on CYW20819? 
 

[AnjanaM_61 · Accepted solution]

Hello @amorniroli 

CYW20819 is not promoted for Bluetooth audio solutions. 

We suggest you to check CYW20706 or CYW20721B2 chip for audio applications.

Regards,

Anjana

[amorniroli]

Hi,

thank you very much for info.

Alessandro