nRF54L15 HCI_LE_CS_Test

[Lee1823]

Hello,

I am developing Channel Sounding Test Mode functionality using nRF Connect SDK (NCS) v3.1.1 and the nRF54L15 Development Kit (DK), based on Nordic’s official hci_uart sample. Initially, I found that the default sample did not support sending Channel Sounding-related HCI commands.

To resolve this, I modified the prj.conf file by adding the following configuration entries:

CONFIG_BT_CHANNEL_SOUNDING=y
CONFIG_BT_CTLR_CHANNEL_SOUNDING=y
CONFIG_BT_CTLR_CHANNEL_SOUNDING_TEST=y

After applying these changes, I further configured the host and controller via HCI commands:

• Used LE Set Host Feature to enable Channel Sounding (Host Support)
• Used Set Event Mask to enable LE Meta Events
• Used LE Set Event Mask to configure the LE event mask

With these settings in place, I can successfully run interactive Channel Sounding functionality by sending HCI commands from a Linux host to the nRF54L15 controller.

However, when attempting to enter Test Mode using the same approach by sending the HCI_LE_CS_Test command as specified in the official Bluetooth Core Specification, the nRF54L15 controller consistently responds with an Invalid HCI Command Parameters (0x12) error. The attached images show the command I sent via hcitool and the packet capture logs from btmon.

Could you please advise on the root cause of this issue and what modifications I need to make to resolve it?

Thank you for your assistance!

[tesc]

Hi,

I see there is a CONFIG_BT_CHANNEL_SOUNDING_TEST as well, but from what I understand that is for the host. You seem to run the host not on an nRF device, but rather a Linux system using hcitool. On that note: Does your hcitool support channel sounding test commands?

Regards,
Terje

[Lee1823]

Yes, my nRF device is currently acting only as a Bluetooth controller, with the host functionality provided by a Linux system.

The version of hcitool I am using is outdated and unable to parse Channel Sounding-related HCI commands. As a result, it displays Unknown when attempting to send such commands.

However, I am only using hcitool as a means to send raw HCI commands, and the nRF controller is still able to receive these raw HCI commands correctly. My judgment is based primarily on whether the status field in the HCI Event returned by the nRF controller indicates Success.

All HCI commands I have sent for establishing connections and performing interactive Channel Sounding procedures have been successful. Yet, when sending the HCI_LE_CS_Test command, the controller consistently returns the error status Invalid HCI Command Parameters (0x12).

[tesc]

Hi,

It looks like you have another ticket which is a continuation of this one, with fundamentally the same underlying issue (sending an HCI_LE_CS_TEST command and get a successful response.) Did you get further, and therefore create the ticket nRF54L15 HCI_LE_CS_TEST Unsupported Feature or Parameter Value (0x11)? If so, then please continue the discussion there.

Regards,
Terje

[Lee1823]

Yes, both questions were posted by me, but I still haven't found a solution to either problem.