Bluetooth GATT Protocol#

These pages provide information about the following topics:

• Server and Client Roles: Reviews information needed for an effective custom profile implementation, such as how a BLE connection works, what roles are played by the devices involved, and how data is transferred from one device to the other over the air.

• Acknowledged vs. Unacknowledged GATT Operations: Explains the difference between acknowledged and unacknowledged GATT operations.

• Polymorphic GATT: Describes the Polymorphic GATT feature, which can be used to dynamically show or hide GATT services and characteristics.

• GATT Caching: Explains how to use the GATT Caching feature so that every remote device can make sure it is storing the latest version of the GATT database structure.

• Service Change Indications: Discusses using the service change characteristic to notify the client to rediscover services on a change in the GATT server.

• Different Value Types of Characteristics: Discusses profiles, services, and characteristics, and describes the uses for different characteristic value types.

• GATT Operation Flowcharts: Provides sequence diagrams and discussion of the procedures defined in the "Generic Attribute Profile" (GATT) of the BLE stack.