send SMS with SIM900 to GSM v2 shield module

I can not send an SMS from SIM 900 to shield modulev2.I am still a beginner in arduino.
Please help me!!
here is my code to send SMS

#include <SoftwareSerial.h>

SoftwareSerial SIM900(7, 8);

String outMessage = "Hello world!";
String destinationNumber = "+447751123456";

void setup()
delay(20000); // give time to log on to network.
SIM900.println("AT + CMGS = "" + destinationNumber +""");
SIM900.write((char)26); //ctrl+z

void loop()

And here is my code to receive SMS

SMS receiver

This sketch, for the Arduino GSM shield, waits for a SMS message
and displays it through the Serial port.


  • GSM shield attached to and Arduino
  • SIM card that can receive SMS messages

created 25 Feb 2012
by Javier Zorzano / TD

This example is in the public domain.


// include the GSM library
#include <GSM.h>

// PIN Number for the SIM
#define PINNUMBER ""

// initialize the library instances
GSM gsmAccess;
GSM_SMS sms;

// Array to hold the number a SMS is retreived from
char senderNumber[20];

void setup() {
// initialize serial communications and wait for port to open:
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only

Serial.println("SMS Messages Receiver");

// connection state
boolean notConnected = true;

// Start GSM connection
while (notConnected) {
if (gsmAccess.begin(PINNUMBER) == GSM_READY) {
notConnected = false;
} else {
Serial.println("Not connected");

Serial.println("GSM initialized");
Serial.println("Waiting for messages");

void loop() {
char c;

// If there are any SMSs available()
if (sms.available()) {
Serial.println("Message received from:");

// Get remote number
sms.remoteNumber(senderNumber, 20);

// An example of message disposal
// Any messages starting with # should be discarded
if (sms.peek() == '#') {
Serial.println("Discarded SMS");

// Read message bytes and print them
while (c = {

Serial.println("\nEND OF MESSAGE");

// Delete message from modem memory
Serial.println("MESSAGE DELETED");



I will wait for your favorable response. Help me!!!

Ok, save yourself some pain.
Get one side working at a time.
Use your mobile phone as the’other’ side.

Once you have both sides working individually, you can work on part 3 - getting them to talk teach other.

ok, thank you but I must use two module GSM because it is the specifications of my project. appreciate your help

Think harder about my first reply...!
If you don’t understand that, you’re doing the wrong course.

We’ll never write your code, or ‘make it work’ - for you.
We’ll tell you how, then you learn something as you move forward.
At the moment, the score is 1-0 in our favour.