This presentation describes how to send and receive data between two Arduino boards using RN-42 Bluetooth.

1. INTERFACING TWO ARDUINO
BOARDS USING RN-42
BLUETOOTH
Presented By:
Sumit chakraborty

3. Basic Command Sets
STEP- 1:

4. Cont..
STEP- 2: Connect Your device With bluetooth and pc.
STEP -3 : Change to command mode($$$)
STEP -4: Press D to see your Bluetooth configuration.

5. Cont..
Some Basic Modes Of Operation
1. Slave Mode(SM,0) – This is default mode.
2. Master Mode(SM,1) – This mode is useful when
the device wants to initiate connection

6. Command Mode VS Data Mode
Upon power up the device will be in data mode. To
enter command mode, send the characters “$$$”
through the serial port or from the remote
Bluetooth connection.
To exit command mode, send “---<cr>”

7. HOW TO CHANGE THE Baudrate
Default Baudrate is 115200
To change to 9600 – SU,96
Range of Baudrate the module supports:
{1200, 2400, 4800, 9600, 19.2, 28.8, 38.4,
57.6, 115K, 230K, 460K,
921K },

8. Program of Master Bluetooth
module
//Master
// Before going forward first Download TextFinder.h
#include <TextFinder.h>
String Remote ="00066649533C"; // Address of slave device
void setup()
{
Serial.begin(9600);
//baudrate
Serial.print("$$$");
// command mode
delay(100);
Serial.println("c,"+ Remote +"r");
// connect to the device
delay(100);
Serial.println("SM,1");
// master
delay(100);
Serial.println("---,"+ Remote +"r");
// exit from command mode and enter data mode
delay(100);
}

9. Cont..
void loop()
{
Serial.println("L"); // Send ‘L’ in data mode
delay(100);
Serial.println("H"); // Send ‘H’ in data mode
delay(100);
}

10. Program for Slave Blutooth module
//Slave
#include <TextFinder.h>
String Remote ="0006664953B0"; // Address of master bluetooth
void setup()
{
Serial.begin(9600);
// baudrate
Serial.print("$$$");
// command mode
delay(100);
Serial.println("c,"+ Remote +"r");
// connecting to the slave
delay(100);
Serial.println("SM,0");
// slave mode
delay(100);
Serial.println("---,"+ Remote +"r");
// exit from command mode
delay(100);
}

11. Cont..
void loop()
{
if(Serial.available() > 0) // Check if data is available
{
char ch = Serial.read(); // read the incoming data
if(ch == 'L')
{
digitalWrite(13,HIGH);
delay(100);
}
else if(ch == 'H')
{
digitalWrite(13,LOW);
delay(100);
}
}
}