[Solved] Problem reading SMS from Sim900 GSM/GPRS shield

Projects Networking, Protocols, and Devices
1

I have been messing around with a GSM/GPRS Shield on an Arduino uno. The plan is to send the Arduino an SMS and it replies. Everything was working but I wasn't deleting the messages after receiving so I assumed the SIM memory was full. After deleting all the messages on the SIM card the serial monitor only displays a blank space where the message should be. I tried another SIM card so the code should work.

Here's the code, it's just an example sketch in the library I'm using (GitHub - MarcoMartines/GSM-GPRS-GPS-Shield: GSM/GPRS & GPS Shield Library for modules using SIM900/SIM908).

#include "SIM900.h"
#include <SoftwareSerial.h>
//If not used, is better to exclude the HTTP library,
//for RAM saving.
//If your sketch reboots itself proprably you have finished,
//your memory available.
//#include "inetGSM.h"

//If you want to use the Arduino functions to manage SMS, uncomment the lines below.
#include "sms.h"
SMSGSM sms;

//To change pins for Software Serial, use the two lines in GSM.cpp.

//GSM Shield for Arduino
//www.open-electronics.org
//this code is based on the example of Arduino Labs.

//Simple sketch to send and receive SMS.

int numdata;
boolean started=false;
char smsbuffer[160];
char n[20];

void setup()
{
     //Serial connection.
     Serial.begin(9600);
     Serial.println("GSM Shield testing.");
     //Start configuration of shield with baudrate.
     //For http uses is raccomanded to use 4800 or slower.
     if (gsm.begin(2400)) {
          Serial.println("\nstatus=READY");
          started=true;
     } else Serial.println("\nstatus=IDLE");

     if(started) {
          //Enable this two lines if you want to send an SMS.
          //if (sms.SendSMS("3471234567", "Arduino SMS"))
          //Serial.println("\nSMS sent OK");
     }

};

void loop()
{
     if(started) {
          //Read if there are messages on SIM card and print them.
        /**  deprecated method
        if(gsm.readSMS(smsbuffer, 160, n, 20)) {
               Serial.println(n);
               Serial.println(smsbuffer);
          }
          **/
          //get 1st sms
          sms.GetSMS(1,n,smsbuffer,160);
          Serial.println(n);
          Serial.println(smsbuffer);
          
          delay(1000);
     }
};

Any help would be much appreciated.