SWRA475A January   2015  – October 2016 CC2540 , CC2540T , CC2541 , CC2541-Q1

 

  1.   Bluetooth low energy Beacons
    1.     Trademarks
    2. 1 What is a Beacon?
    3. 2 Bluetooth low energy and Bluetooth Smart
      1. 2.1 Non-Connectable Beacons
      2. 2.2 Connectable Beacons
      3. 2.3 Data Packet
      4. 2.4 Device Address
        1. 2.4.1 Flags
        2. 2.4.2 Manufacturer Specific Data
      5. 2.5 Broadcast Interval
      6. 2.6 Power
      7. 2.7 Range
      8. 2.8 Coexistence
    4. 3 Designing a Bluetooth low energy Beacon
      1. 3.1 Development Kits
      2. 3.2 Creating a Beacon Application With TI Bluetooth low energy-Stack
    5. 4 iBeacon Implementation
      1. 4.1 Overview and Prerequisites
      2. 4.2 Design and Implementation
      3. 4.3 Testing
    6. 5 Proprietary Implementation
      1. 5.1 Overview and Prerequisites
      2. 5.2 Design and Implementation
      3. 5.3 Testing
    7. 6 References
  2.   Revision History

2.4 Device Address

The broadcast address can be either public or random. A public address [1] (Vol.6.C.1.3 page 2500) is an IEEE 802-2001 standard and uses an Organizationally Unique Identifier (OUI) obtained from the IEEE Registration Authority. Texas Instruments provides IEEE addresses for all Bluetooth Smart devices. Random addresses can be directly generated by the beacon and can be of three different types: static, non-resolvable private and resolvable private. Static addresses are not allowed to be changed unless the device power cycles. A private address can change over time and a resolvable address can be used to derive the true address. A non-resolvable address can also change over time, which is the differentiation compared to a static address. The random address is a privacy feature that prevents tracking of a specific device. There are specific rules when generating random addresses and the details can be found in the Core Specification [1] (Vol3.C.10.8 page 2020).

Figure03_SWRA475.gifFigure 3. Beacon Address Types

The broadcasted data can be formatted according to Bluetooth SIG specified data formats, with some examples shown in Table 2[2], [3]. For the purpose of this application report, the focus is on the Flags and Manufacturer-Specific Data.

Table 2. Advertisement Data Types

AD Data Type Data Type Value Description
Flags 0x01 Device discovery capabilities
Service UUID 0x02 - 0x07 Device GATT services
Local Name 0x08 - 0x09 Device name
TX Power Level 0x0A Device output power
Manufacturer Specific Data 0xFF User defined