SENDING MESSAGE WITH ARDUINO WITH ORDINARY GSM MODULE (NO GSM SHIELD) WITH AT COMMANDS

Using a GSM module with arduino for sending message ..


1.  Find your GSM modules Baud rate
2. Connecting to Arduino .. You need to connect only 3 pins from GSM to Arduino
        *  RX from Arduino to TX of GSM
        *  TX from Arduino to RX of GSM module
        *  GND pin from GSM to GND of Arduino..

MAKE SURE THAT U HAVE CONNECTED ALL PINS CORRECTLY !!

If yes ! .. your hardware interfacing is Over .. !

Now , about the Arduino program. We have a library already in Arduino called GSM.h .
Here , we are not using that because we are not using GSM shield so there is a chance of error..
This method is simple though . we use simple "Serial" function and "String"  function.

Program for sending a message ..follows ..
////////////////////////////////////////////////////////////////////////////////////////////

void setup()
{
Serial.begin(9600); // Baud rate of the GSM Module
}
void loop()
{
SendTextMessage();
delay(2000);
}
void SendTextMessage()
 {

  Serial.println("AT");    //Because we want to send the SMS in text mode
  delay(100);
  Serial.println("AT+CMGF=1");    //Because we want to send the SMS in text mode
  delay(100);
  Serial.println("AT+CMGS=\"+91******\"\r"); // change to the phone number you using
  delay(100);
  Serial.println("A test message!");//the content of the message
  delay(100);
  Serial.println((char)26);//the ASCII code of the ctrl+z is 26
  delay(100);
  }

////////////////////////////////////////////////////////////////////////////////////////////////

This Code will Send message continuously every 2 seconds.

To restrict to a single message, use it n setup function or

int a =0; 

void setup()
{
Serial.begin(9600); // Baud rate of the GSM Module
}
void loop()
{
if(a=0)
{
SendTextMessage();
a=1;
}
delay(2000);
}
void SendTextMessage()
 {

  Serial.println("AT");    //Because we want to send the SMS in text mode
  delay(100);
  Serial.println("AT+CMGF=1");    //Because we want to send the SMS in text mode
  delay(100);
  Serial.println("AT+CMGS=\"+91******\"\r"); // change to the phone number you using
  delay(100);
  Serial.println("A test message!");//the content of the message
  delay(100);
  Serial.println((char)26);//the ASCII code of the ctrl+z is 26
  delay(100);
  }

/////////////////////////////////////////////////////////////////////////////////////////////////////
Here we declare 'a' as a flag. Initially a is set to zero and anfter sending the messgae, we just pull the value of a to one so that it comes out of the loop.

  ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

Queries accepted ..willing to help if your problem is inside my range of knowledge :)  

Mail me : nikhiljoji@gmail.com