AN91162 Datasheet, PDF (6/43 Pages) Ramtron International Corporation – Creating a BLE Custom Profile

Creating a BLE Custom Profile
 Permissions: Permissions describe the access permissions for the data. Permission settings are provided for Encryption,
Authentication, and Authorization.
 UUID: The UUID value (128-bit) uniquely identifies the characteristic.
In the RGB LED Control example, the defined characteristic sends an array of four bytes, one byte defining each of the color
values of the RGB LED, and one byte to control intensity. The definition of the characteristic depends on how the application
interprets the data. The property of this characteristic is “Write” because the GATT client writes the new RGB LED values to
the GATT server.
Similarly, you can add another characteristic that will provide the 2-byte temperature information from an onboard heat sensor
that monitors LED overheating. Figure 5 provides an overview of the characteristics described above.
Figure 5. Define Characteristic in Service
Service 1
(RGB LED Control)
Characteristic 1
(RGB LED Color)
Data type: array, 4 bytes
Property: Write
Characteristic 2
(LED Temperature)
Data type: 2 bytes
Property: Read, Notify
Defining Descriptors
Depending on the characteristics, you may add descriptors. These descriptors provide information to the user about
characteristics. They can also be used by the GATT client device to enable or disable notifications and indications.
An example of descriptors under a custom characteristic is shown in Figure 6. In this example, a descriptor, termed Client
Characteristic Configuration, is used by the GATT client to enable and disable notifications or indications. This is under the
characteristic that supports notification or indication. Another example descriptor is the Characteristic User Description, which
provides a string through which the characteristic can be recognized in a human-readable format.
Figure 6. Define Descriptor in Characteristics
Characteristic 1
Value
Descriptor 1
Client Characteristic Configuration
(Enable/Disable Notification)
Descriptor 2
Characteristic User Description
(String: RGB LED Control)
PSoC Creator Project: RGB LED Custom Profile
To create and verify this project, ensure that you have the following prerequisites:
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Document No. 001-91162 Rev. *A
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