Describes Bluetooth protocol in the application layer, Uses Java to explore Bluetooth technology using JSR-82. Has separate discussions for : 1) concept of local and remote device 2) Find out your own MAC Address (Bluetooth ) 3) Search for devices 4)Connect to a device over BTSPP 5) Use javax.microedition.io 6) It also works with Java ME (J2ME) 7) concept of UUID and profiles 9) It connects to DUN profile 10) Using AT commands to ethically make calls from another GSM mobile or send SMS from it

1. Programming with JSR-82
Soham Sengupta,
Sr. Lecturer, Dept of IT,
JIS College of Engineering
Author, IBM dW, IBM,US
Community Contributor to Nokia JME Forum
& SourceForge,
Formerly, Systems Engineer, TCS

2. Bluetooth Technology
 A short distant Wireless Technology
 79 channels around 2.4 GHz ISM band
 GFSK
 Range 10m, 20m, 100m
 Bluetooth v2.1 speeds up to 3 Mbps
 IEEE 802.15 standard
 You’d learn in details about it later
October 13, 2014 sohamsengupta@yahoo.com 2

3. JSR-82: what and why
 JSR stands for Java Specification
Request
 JSR-82 is the one for designing API for
Bluetooth.
 Presently JSr-82 exists in Java SE and
ME, both. So, it’s possible to
programmatically set up and build app
layer protocol between 2 BT devices.
October 13, 2014 sohamsengupta@yahoo.com 3

4. A Look into JSR-82 compliant
Blucove v2.1
 javax.bluetooth.DiscoveryAgent;
 javax.bluetooth.DiscoveryListener;
 javax.bluetooth.LocalDevice;
 javax.bluetooth.RemoteDevice;
 javax.bluetooth.ServiceRecord;
 javax.bluetooth.UUID;
 javax.microedition.io.*;
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5. Getting Hardware Address of
a device and its HF name
 LocalDevice localDevice =
LocalDevice.getLocalDevice();
System.out.println("Address:
"+localDevice.getBluetoothAddress());
System.out.println("Name:”+localDevice
.getFriendlyName());
October 13, 2014 sohamsengupta@yahoo.com 5

6. Bluetooth Life Cycle in BTSPP
1. Initialize Bluetooth Stack
2. Search for devices in range
3. After device inquiry completes, select a
device from, say, a UI or console
4. Search for service, defined by a UUID, on
the device
5. If service is available, set up a btspp
connection
6. Now apply App. Rules to transfer data/cmd
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7. UUID: what and why
 It’s a 16-bit/32-bit/ 128-bit HEX integer, to
identify a service uniquely
 Generally, 128-bit UUIDs are user defined
and the probability that 2 devices offer the
same service in a short range is 2^(-2*128).
 16-bit UUID are occupied by several pre-defined
App. Services like DUN, OBEX, HSP
etc.
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8. UUID contd.
 UUID u=new UUID("1103",true);
 The above u is a 16-bit pre-defined one.
 It’s for DUN (Dial-up-Network)
 True is passed to the constructor to
signify that it’s a short one.
 false means it’s a 128-bit one.
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9. Searching for Devices…
 LocalDevice localDevice =
LocalDevice.getLocalDevice();
 DiscoveryAgent agent =
localDevice.getDiscoveryAgent();
 agent.startInquiry(DiscoveryAgent.GIAC,
dscListerner);
 GIACGeneral Inquiry Access Code
 dscListerner is an object of DiscoveryListener
October 13, 2014 sohamsengupta@yahoo.com 9

10. Interface DiscoveryListener (4
methods)
1. public void deviceDiscovered(RemoteDevice
btDevice, DeviceClass cod)
2. public void inquiryCompleted(int discType)
3. public void servicesDiscovered(int transID,
ServiceRecord[] servRecord)
4. public void serviceSearchCompleted(int transID, int
respCode)
You have to override these four methods as required.
October 13, 2014 sohamsengupta@yahoo.com 10

11. Searching for service
 agent.searchServices(null,uuidSet,remo
teDevice,bluetoothServiceDiscovery);
 uuidSet: UUID[]
 remoteDevice: RemoteDevice
 bluetoothServiceDiscovery:
DiscoveryListener
 null/ int[] defines attribute sets
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12. Obtaining Connection
 Once service is found,
 StringconnectionURL=servRecord[0].getConn
ectionURL(0,false);
 StreamConnection
conn=(StreamConnection)Connector.open(co
nnectionURL);
 DataOutputStream
dos=conn.openDataOutputStream();
 DataInputStream
dis=conn.openDataInputStream();
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13. Now we can send data/cmd
 dos.writeUTF(“Hello”); dos.flush();
 String x=dis.readUTF();
 dos.write(data,0,length); dos.flush();
 Now we shall connect to a Mobile
Device and access the DUN service
October 13, 2014 sohamsengupta@yahoo.com 13

14. AT command
 Commands to Ctrl GSM Modems
 Mobile phones, too, respond to them
 The command to dial a Ph. No. is
ATD 9830740684; (The ; makes it a voice
call without which it’s a data call).
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