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AD flags needed in every advertising packet?

Hi,

to be able to send more advertising data, i want to cyclical switch between different advertising packages. This already works so far. Do i need to include the AD flags in every advertising package or is it enough to include the AD flags in only one of my packages?

  • Hi,

    Yes, you need to have the AD Flags in every advertising packet.

    In the Bluetooth Core Specification Supplement it is stated that: “The Flags data type shall be included when any of the Flag bits are non-zero”. Since the Softdevice only supports Bluetooth LE the "BR/EDR not supported"-bit must always be set and hence, the AD Flags must be included.

  • Actually, you can omit the AD flags if you don't need it to be connectable. The specification reads:

    1.3 FLAGS

    1.3.1 Description

    The Flags data type shall be included when any of the Flag bits are non-zero and the advertising packet is connectable, otherwise the Flags data type may be omitted.

    So MME can actually do what he hoped, i.e. get 3 extra bytes of payload, as long as the sending device is non-connectable.   :)