This document provides an overview of Bluetooth Low Energy (BLE) terminology, protocol stack, service organization, and advertising/connection sequences. It discusses BLE versions and their data rates. The protocol stack includes Generic Access Profile (GAP), Generic Attribute Profile (GATT), Attribute Protocol (ATT), and Security Manager (SMP). GATT defines services, characteristics, and attributes. Advertising and connection sequences are described. The document also outlines scanning for BLE devices, connecting to a device, discovering services, and setting notifications to receive data from a device's characteristics.

1. BLE

2. Outline
• BLE
•

3. Terminology
Term Generation Introduction
BR 1.1 (2002) Basic Rate (1 Mbps)
EDR 2.0 (2004) Enhanced Data Rate (2 -3 Mbps)
HS 3.0 (2009) High Speed (AMP: 24 Mbps)
LE 4.0 (2010) Low Energy (ultra low power:1
Mbps )
Bluetooth smart 4.0 Single mode
Bluetooth smart
ready
4.0 Dual mode
Classic
bluetoo
th

4. Introduction- Applications
Wireless headset,
printer,etc.
(Bulk data)
PCs, smartphones,etc.
(Communicate with smart & classic
bluetooth)
Remote control, heart
rate monitor,etc.
(Small data)

5. Protocol Stack
GATT: Generic Attribute Profile.
GAP: Generic Access Profile.
ATT: Attribute Protocol.
SMP: Security Manager.
L2CAP: Logical Link and Adaption
Protocol.
SIG Service (Profile)

6. Protocol Stack
GAP:
Device discovery.
Connection establishment.
Initiation of security features.

7. Protocol Stack
• GATT: It defines the framework
that uses the ATT to service
discovery, read , write and
exchange values data transferred
from one device to another.
• ATT table organization:
Service->Characteristics-
>Attributes
ATT table
Service 1
Cha
r.
Att
r.
Att
r.
Cha
r.
Att
r.
Att
r.
Cha
r.
Att
r.
Att
r.
Service 2
…

8. Service Organization
Column
Handle: Index of attribute table (Identify attribute in Firmware)
UUID: Identify type in each row
Permissions: Data R/W permission
Value: Info. (value) of one attribute
Row attribute UUID
Service: Characteristic (1…N)
Characteristic attribute (1…N)
Characteristic Descriptor (0…N)

9. Attribute Permission
• Read
• Mobile Attribute value
• Write
• Mobile Attribute value
• Notify
• Mobile Characteristic Descriptor
( CCCD) 0x0100 = enable, 0x0000 = disable
• Characteristic value

10. Link-Layer State (Device)
Listen to advertising packets
Transmit advertising
packets
Listen to advertising
packets & respond to
initiate a connection

11. Advertising Sequence
Device Radio Scanner
Set advertisement data
Set local bluetooth
address
Start advertising
ADV packet
ADV packet
ADV packet
BLE_GAP_EVT_TIMEO
UT
Case 1:Timeout

12. Connection Sequence
Device Radio Mobile
Connection
request
BLE_GAP_EVT_DISCONNECT
ED
BLE_GAP_EVT_CONNECT
ED
Connection
termination
Advertisement
Case 1:Disconnection
Connection establishment

13. Service Discovery
Sequence
Device Radio Mobile
ATT write request
BLE_GATT_EVT_WRITE
ATT write
responseSend heart rate &
battery
data packet
ATT packet sending
ATT table
Heart rate service
Battery service

14. Outline
• BLE
•
• Activity BLE Device Scan
• Service BLE
• Activity UI BLE Service

15. Scan Device
In activity

16. Connect DeviceIn service

17. Discover Services (1/2)
In service
method

18. Discover Services (2/2)
In service
In activity
Service mBluetoothGatt Gatt

19. Set Notification (1/4)
In activity

20. Set Notification (2/4)
Descriptor UUID? app
Device CCCD UUID
<- ?
In service

21. Set Notification (3/4)
In service
http://stackoverflow.com/questions/17910322/android-ble-api-gatt-notification-not-received
@API LEVEL 18
Notify(1/4 )

22. Set Notification (4/4)
In service
Read ( notify read)