Bluetooth LE advertising module

In nRF Desktop, the Bluetooth® LE advertising module is responsible for controlling the Bluetooth LE advertising for the nRF Desktop peripheral device.

Module events

Source Module

Input Event

This Module

Output Event

Sink Module

Bluetooth LE advertising module



Bluetooth LE state module

Bluetooth LE bond module


Source modules for module_state_event


Power manager module


Buttons module


HID forward module

Motion module

Power manager module

Wheel module


Sink modules for ble_peer_event


LED state module


Sink modules for module_state_event


See the Overview: Firmware architecture for more information about the event-based communication in the nRF Desktop application and about how to read this table.

Implementation details

nRF Desktop uses the Bluetooth® LE advertising module from Common Application Framework (CAF). See the CAF Bluetooth LE advertising page for implementation details.

For more information about Bluetooth configuration in nRF Desktop, see Bluetooth in nRF Desktop.

Avoiding connection requests from unbonded centrals when bonded

If the Bluetooth local identity currently in use already has a bond and the nRF Desktop device uses indirect advertising, the device will not set the General Discoverable flag. The nRF Desktop devices also enable CONFIG_BT_FILTER_ACCEPT_LIST to mark incoming scan response data requests and connection requests as acceptable. This is done to prevent Bluetooth Centrals other than the bonded one from connecting with the device. The nRF Desktop dongle scans for peripheral devices using the Bluetooth device name, which is provided in the scan response data.

Transmission power level

Bluetooth TX power level is assumed to be 0 dBm during advertising. This value is sent in unbonded advertising.