RN-42-SM Bluetooth Transmitter with Arduino Nano

Projects Networking, Protocols, and Devices
4

I was able to get the Arduino to talk to the RN-42! What was really needed was to reduce the baud rate on the module from 115200 to 9600 and short the RTS&CTS pins. To do this I had to do the following:

  1. Connect the module to a female RS232 and connect the cable to a computer.
  2. Open Putty (or any form of Hyperterminal).
  3. Select the port that the cable is connected to and type 115200 for the speed.
  4. At this point the user should be able to type in the commands to access the command mode by entering "$$$", and after changing the baud rate all that is needed to exit is "---".

By doing this I was able to properly communicate with the Arduino and develop this sample code:

/*  Created 03/01/2013 
    Jordan Shelter 
    Bluetooth Adapter Test
 
 Background: 
 This is sketch is based on the software serial example.
 
 Hardware:
 -  Roving Networks RN42-SM
 -  Arduino Nano 3.0 
 
 The circuit: 
 * RX(18) is digital pin 10 
 * TX(19) is digital pin 11 
 * RTS & CTS shorted on RN42
 
 Note:
 Not all pins on the Mega and Mega 2560 support change interrupts, 
 so only the following can be used for RX: 
 10, 11, 12, 13, 50, 51, 52, 53, 62, 63, 64, 65, 66, 67, 68, 69
 
 Not all pins on the Leonardo support change interrupts, 
 so only the following can be used for RX: 
 8, 9, 10, 11, 14 (MISO), 15 (SCK), 16 (MOSI).
 */
 
#include <SoftwareSerial.h>

SoftwareSerial mySerial(10, 11); // RX, TX

void setup()  
{
  // Open serial communications and wait for port to open:
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }


  Serial.println("Goodnight moon!");

  // set the data rate for the SoftwareSerial port
  mySerial.begin(9600);
 }

void loop() // run over and over
{
  mySerial.write("Fred was here");
  mySerial.write(13);
  mySerial.write(10);
  delay(1000);
  while (mySerial.available()!=0)
  {
   Serial.write(mySerial.read());
   delay(100);
  }
  
}