Arduino GSM shield GSM_READY not ready ever

Question

I am using an Arduino Mega and an Arduino GSM shield. I am using the receive SMS example under GSM in the Arduino IDE. My GSM shield's hardware IP is set correctly.

Here is the sketch:

/*
 SMS receiver
 This sketch, for the Arduino GSM shield, waits for a SMS message
 and displays it through the Serial port.
 Circuit:
 * 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.
 http://arduino.cc/en/Tutorial/GSMExamplesReceiveSMS
*/
// 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:
 Serial.begin(9600);
 while (!Serial) {
 ; // wait for serial port to connect. Needed for Leonardo 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");
 delay(1000);
 }
 }
 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);
 Serial.println(senderNumber);
 // An example of message disposal
 // Any messages starting with # should be discarded
 if (sms.peek() == '#') {
 Serial.println("Discarded SMS");
 sms.flush();
 }
 // Read message bytes and print them
 while (c = sms.read())
 Serial.print(c);
 Serial.println("\nEND OF MESSAGE");
 // Delete message from modem memory
 sms.flush();
 Serial.println("MESSAGE DELETED");
 }
 delay(1000);
}

The issue is this line:

if (gsmAccess.begin(PINNUMBER) == GSM_READY)

The serial monitor outputs everything until that line.

It just never gets past it, so I assume it cannot connect? The SIM has no pin code: I have tried it with my phone. The SIM has full signal strength when in my phone. I have tried my other SIM card also but the same thing happens.

This seem to be the same question, yet no answer: http://forum.arduino.cc/index.php?topic=270551.0

• user7154: I have the same problem. Did you fix it and if yes, how did you do? It's been a few days and still didn't find a way to fix it.

Answer 1

You could always try setting a pin code and then retry http://arduino.cc/en/Tutorial/GSMToolsPinManagement

What version of the Arduino IDE are you using ? Also, are you sure you are suppying the board correctly ? "It is recommended that the board be powered with an external power supply that can provide between 700mA and 1000mA. Powering an Arduino and the GSM shield from a USB connection is not recommended, as USB cannot provide the required current for when the modem is in heavy use."

Answer 2

I Have The Same Problem. But First Of All you have to set your modem Network Band according to your cellular Network Band.

GSMBand band;
String newBand= "GSM_MODE_EGSM_DCS";// Your Band In My case That was 
 band.begin();
 Serial.println("Modem restarted.");
 String bandName = band.getBand(); // Get and print band name
 Serial.print("Current band:");
 Serial.println(bandName);
band.setBand(newBand);

Band Help:

 GSM_MODE_EGSM ---- E-GSM(900)
 GSM_MODE_DCS ---- DCS(1800)
 GSM_MODE_PCS ---- PCS(1900)
 GSM_MODE_EGSM_DCS ---- E-GSM(900)+DCS(1800) ex: Europe
 GSM_MODE_GSM850_PCS ---- GSM(850)+PCS(1900) Ex: USA, South Am.
 GSM_MODE_GSM850_EGSM_DCS_PCS ---- GSM(850)+E-GSM(900)+DCS(1800)+PCS(1900)

Then You Have To use

gsm.access.begin();

Answer 3

I had the same problem. Then I used gsm.shutdown(); before gsm.begin(PINNUMBER). After that it goes past gsm.begin(PINNUMBER) but not always. I don't know if this is the right way to do it, but it works for me.