Hello kind people!
I’m very new to Arduino. I have been trying to use the ready made code from Arduino library to receive an sms, but up to no avail.
The serial monitor displays only:

SMS Messages Receiver
GSM initialized
Waiting for messages

I am using SIM900 v2.0 connected to Arduino/Funduino UNO and I think that I have a good network conection as the green LED blinks every 3 seconds as it should. I have sent sms numerous to it, but theyare never received. The code compiles very well and I do not have error in it.
The code is:

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 = false;

// 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”);



Does anyone have a clue as to why I am no receiving any sms.

I will deeply appreciate your reply.

Thank you in advance.


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