What is handle in Ble?

What is handle in Ble?

Low energy device attributes contain a 16-bit address called the attribute handle. Each handle is associated with an attribute Universally Unique Identifier (UUID) that is 128-bits long. In the attribute database, the handle is unique while the UUID is not unique.

What is connection handle in Bluetooth?

A connection handle is a 12 bit representation of a channel connection between two Bluetooth devices. The connection handle is used within a host-controller device. There can be multiple connection handles between two Bluetooth devices. However, they all refer to the same ACL channel.

How do I connect to my BLE device?

Connect BLE device to Android an Send Data (nUART)

1. connect to the device (static MAC-address)
2. connect to the nordic-UART-service.
3. receive texts from the Feather.
4. implement surveillance of the connection.

What is characteristic in Ble?

Inside the characteristic, you have an attribute that is the value of the characteristic and one or more descriptors that are themselves attributes. You can see the attribute concept as the abstract type you can define concrete types like service, characteristic and descriptors.

What is client characteristic configuration?

The “Client Characteristic Configuration” descriptor contains information about whether notification or indication is enabled or disabled. You can use read to get the current data. data = read(d) data = 1×2 0 0. Interpret this data by referring to the specification for this descriptor on the Bluetooth SIG website.

What is GATT client?

A GATT Client is a device which accesses data on a remote GATT Server, paired via BLE, using read, write, notify, or indicate operations. Once two devices are paired each device can act as both a GATT Server and a GATT Client.

Which modulation technique is used in Bluetooth communication?

Gaussian Frequency Shift Keying
Bluetooth technology uses a special binary frequency shift keying modulation scheme called Gaussian Frequency Shift Keying (GFSK). It’s a binary modulation scheme because each symbol represents only one bit, with a value of either zero or one.

How does BLE communication work?

BLE uses a hierarchical data structure to define the information exchange structure. A BLE device acting as a peripheral will advertise services and characteristics that can be used for communication with the device. Characteristics expose values as small packets of information that can change over time.

How many characteristics can a BLE service have?

A service can have one or more characteristics, and each service distinguishes itself from other services by means of a unique numeric ID called a UUID, which can be either 16-bit (for officially adopted BLE Services) or 128-bit (for custom services).

What is client characteristic?

The “Client Characteristic Configuration” descriptor contains information about whether notification or indication is enabled or disabled. You can use read to get the current data.

What do you need to know to program a BLE device?

What you need to know to program a BLE device are the UUIDs of the services and characteristics you wish to use. This information is typically found in the documentation from the device manufacturer. Use these UUIDs in the code when making calls to the BLE library functions. Below we show code examples of how to do this.

What does the handle Mean in ble programming?

“handle” is not a BLE concept. It is a common software concept, used by the libraries you are using. See for instance Handle (computing).

Where can I find the UUID for a BLE device?

You use these ids when setting up the communication with the BLE device from JavaScript. The UUIDs are usually found in the device documentation provided by the manufacturer. As an example, we will use the TI SensorTag CC2650 and the Luxometer Service.

How can I learn more about BLE packets?

Learn by analyzing them using a Bluetooth analyzer (sniffer) captures. I believe these two methods go hand in hand in helping achieve a full understanding of BLE. We cover the first aspect in my Intro to Bluetooth Low Energy book (which you can download for free here or purchase in paperback format ).