RE: BLE parameters and channels

haakonsh — Tue, 20 Apr 2021 09:27:54 GMT

[quote user=""]Does the devices scan for high traffic channels and skip those in the SDK examples.[/quote]

No, the SoftDevices uses the standard sudo-random BLE hopping algorithm. The SoftDevices do however have a Quality of Service (QoS) channel survey, that measures the energy level of Bluetooth Low Energy channels. The application can then set an adapted channel map to avoid busy channels.

[quote user=""]what is this access address and how it is determined?[/quote]

By default, the access address is static throughout the lifetime of a BLE device, but if you enable the privacy mode (Private resolvable address) you change this address at given intervals using the RNG — Random number generator and a private address.

The access address is used by the Link Layer to determine which physical device it is talking talking to. With a static address you can identify a device based on its access address alone, but with a private resolvable address you need to also transmit the scrambled private address.

See this artical for more info: https://www.electronicdesign.com/technologies/communications/article/21801870/ble-v42-creating-faster-more-secure-powerefficient-designspart-2.