RE: Title: Clarification on LE Secure Connections and SMP responsibilities when using SoftDevice Controller as HCI controller on nRF52840

Einar Thorsrud — Tue, 24 Feb 2026 12:33:34 GMT

Hi,

[quote user=""]A clear statement of which parts of LE SC/SMP are implemented in SDC vs. expected on the Host in HCI mode.[/quote]

Pairing and bonding is implemented in the host only (see Security Manager in the Bluetooth specification). Therefore, there is no code or APIs for this in the SoftDevice Controller, as that implements a standard Bluetooth HCI interface.

[quote user=""]The list of HCI commands/events that should be used for LE SC and OOB pairing in this architecture.[/quote]

None (see above).

[quote user=""]Any relevant application notes or documentation links that describe this Host + SDC‑as‑HCI‑controller model.[/quote]

This follows the Bluetooth specification. The only integration we support directly is the integration with the Zephyr host in the nRF Connect SDK, so this can be used as a reference. However, as it is a standard HCI interface you only need to refer to the BLE specification for that, and also see the vendor specific commands documented here (though this is may often not be needed). You can see an example of using the SoftDevice Controller with another host (typically BlueZ on Linux) by referring to the Zephyr Bluetooth samples that start with "HCI".