RE: Nordic zephyr-sdk scan behaves differently than upstream zephyr

Akshay Mehta — Thu, 09 Jan 2025 21:23:58 GMT

This is an older forum post, but I wanted to follow up on the current status. Our team specializes in Zephyr and Rust, and we’re ready to assist.

Best,

Akshay

RE: Nordic zephyr-sdk scan behaves differently than upstream zephyr

Sigurd — Mon, 01 Jul 2024 08:04:30 GMT

Hi!

You are likely seeing this limitation here in the SoftDevice Controller:

DRGN-8628: Setting Filter_Duplicates in LE Set Scan Enable and LE Set Extended Scan Enable commands does not take effect

The host receives all advertisements from advertisers in advertising report events even if Filter_Duplicates is set in LE Set Scan Enable and LE Set Extended Scan Enable. Filter_Duplicates cannot guarantee that all duplicate advertising reports are filtered out, because the controller has a limited “cache” of known advertising reports.

Workaround: Filter out the duplicate advertising reports in the application.

https://docs.nordicsemi.com/bundle/ncs-latest/page/nrfxlib/softdevice_controller/limitations.html

[quote user=""]Is there any way to get the upstream behavior when using the nordic zephyr-sdk branch?[/quote]

I would generally recommend using the SoftDevice Controller, it's this Controller we qualify, it's is developed, tested, and supported by Nordic Semiconductor. But to use the Zephyr Bluetooth LE Controller instead, set CONFIG_BT_LL_SW_SPLIT to y in the prj.conf

https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/protocols/bt/ble/index.html#usage_in_samples