HCI USB based on nRF Connect SDK 1.7.0 failed to update connection parameter from slave

[Adrian Eggenberger]

Hi

I've built a HCI USB firmware based on the hci usb example in the nRF Connect SDK for the nRF52840DK. The configuration of the project has been slightly adapter to better support enhanced data length and other features.

/cfs-file/__key/communityserver-discussions-components-files/4/3704.prj.conf

The firmware is used with an own HCI host stack. It is used by an application that emulates a peripheral device.

After the connection is established the application triggers a connection update command "LE Connection Update". The response from the controller is that the provided connection handle is invalid, but the handle is equal to the handle that came with the "LE Enahnced Connection Complete" event.

The full communication with the device can be seen in the attached wireshark log that shows the full HCI communication.

=> /cfs-file/__key/communityserver-discussions-components-files/4/CaptureA.cfa

Timestamp: 0.201 => Connection Established Event
Timestamp: 0.250 => Connection update command
Timestamp: 0.252 => Reject with Unknown Connection Identifier

This failure did not happen when the HCI USB firmware was based on the nRF Connect SDK 1.5.1 and was using the software controller layer.

What can be the reason for this?

Regards Adrian

[Amanda Hsieh]

Hi,

This is a Zephyr Project sample that uses the Zephyr open source link layer.  You may try to use CONFIG_BT_LL_SW_SPLIT=y, and if there is any issue, then a github issue can be created in the Zephyr Project repository.

Regards,
Amanda

[Adrian Eggenberger]

Hi Amanda

Getting support for the samples that come with Zephyr is obviously a bit tricky and to be honest a bit frustrating. The Zephyr team tells me that when using a version of the nRF Connect SDK that they are not involved as it's the Nordic's branch. If I contact the DevZone like in this case I'm told to get in contact with the Zephyr team as it's there example.

However for my current project I'll switch anyway to the pure Zephyr project and use the Zephyr Bluetooth layer as this layer seems to be more matching for the HCI USB usage. See the other issue: (+) HCI USB firmware based on nRF Connect SDK 1.7.0 doesn't filter duplicate advertising reports - Nordic Q&A - Nordic DevZone - Nordic DevZone (nordicsemi.com)

So for me we can close this issue here, but still I think the bug exists when using the Nordic Bluetooth stack (Softdevice Controller).

Regards Adrian