GSM SIM900 Shield w/ Quad-Band GSM

The GPRS Shield is based on SIM900 module from SIMCOM and compatible with Arduino and its clones. The GPRS Shield provides you a way to communicate using the GSM cell phone network. The shield allows you to achieve SMS, MMS, GPRS and Audio via UART by sending AT commands (GSM 07.07 ,07.05 and SIMCOM enhanced AT Commands). The shield also has the 12 GPIOs, 2 PWMs and an ADC of the SIM900 module(They are all 2V8 logic) present onboard.

Applications

• M2M (Machine 2 Machine) Applications
• Remote control of appliances
• Remote Weather station or a Wireless Sensor Network
• Vehicle Tracking System with a GPS module
• Achieve SMS, MMS, GPRS and Audio via UART by sending AT commands (GSM 07.07 ,07.05 and SIMCOM enhanced AT Commands)
• 12 GPIOs, 2 PWMs and an ADC of the SIM900 module (They are all 2V8 logic) present on board.

Features

• Quad-Band 850 / 900/ 1800 / 1900 MHz - would work on GSM networks in all countries across the world.
• GPRS multi-slot class 10/8
• GPRS mobile station class B
• Compliant to GSM phase 2/2+
• Class 4 (2 W @ 850 / 900 MHz)
• Class 1 (1 W @ 1800 / 1900MHz)
• Control via AT commands - Standard Commands: GSM 07.07 & 07.05 | Enhanced Commands: SIMCOM AT Commands
• Short Message Service - so that you can send small amounts of data over the network (ASCII or raw hexadecimal)
• Embedded TCP/UDP stack - allows you to upload data to a web server
• RTC supported
• Selectable serial port
• Speaker and Headphone jacks
• Power supply: 5V ~ 26V DC  (2A power supply is recommend to Arduino or DC jack in this board)
• Low power consumption - 1.5mA (sleep mode)
• Industrial Temperature Range - -40°C to +85 °C
• Size: 8.5 x 5.7 x 2cm

Package Included

GPRS/GSM SIM900 Shield Development Board x 1

Note:

• Make sure your SIM card is unlocked.
• The product is provided as is without an insulating enclosure. Please observe ESD    precautions specially in dry (low humidity) weather.
• The SIM900 card model used does not include pins to directly mount on the ARDUINO, you may link it manually since it is controlled by UART and only need TX and RX.

   Tutorial from: http://www.prometec.net/gprs-llamar-enviar-sms/

MAKING CALLS FROM ARDUINO

We will introduce the card PIN to unlock it using AT commands and we will give you some time to connect to the network. The command that we will use is AT + CPIN = "XXXX " , where we will replace XXXX by the PIN of our card.

 #include <SoftwareSerial.h>
 SoftwareSerial SIM900 (7, 8);  // 10 and 11 for the Arduino Mega.  Configure the serial port for the SIM900. 

  Void setup ()
    {
       // digitalWrite (9, HIGH);  // Uncomment to activate the card power by Software
       // delay (1000); 
       // digitalWrite (9, LOW);
       Delay (5000);  // We give ourselves some time to turn on the GPRS and power the card
       SIM900.begin (19200);  // Set serial port speed for SIM900
       Serial.begin (19200);  // Set Arduino serial port speed
       Serial.println ("OK");
       Delay (1000);
       SIM900.println ("AT + CPIN = \" XXXX \ "");  // AT command to enter the PIN of the card
       Delay (25000);  // Time to find a NETWORK
    } 

  Void call ()
    {
       Serial.println ("Calling ...");
       SIM900.println ("ATDXXXXXXXXX;");  // AT command to make a call
       Delay (30000);  // Wait 30 seconds while making the call
       SIM900.println ("ATH");  // Call dangle
       Delay (1000);
       Serial.println ("Call completed");
    } 

  Void loop ()
    {
       to call();  // Make the call
       While (1);
    } 

SEND SMS

The programming to send an SMS will be identical, but we will create another function that will be in charge of sending the commands AT to send the SMS.

First we will use the AT + CMGF = 1 \ r command to tell the GPRS module that we are going to send a message, and then enter the number to which it is addressed with the command AT + CMGS = "XXXXXXXXX" .

Once this is done, we simply send the content of the message and end it with the ^ Z character. The function would look like this:

 Void message_sms ()
    {
       Serial.println ("Sending SMS ...");
       SIM900.print ("AT + CMGF = 1 \ r");  // Set the text mode to send or receive messages
       Delay (1000);
       SIM900.println ("AT + CMGS = \" XXXXXXXXX \ "");  // Number to which the message will be sent
       Delay (1000);
       SIM900.println ("SMS sent from an Arduino. Greetings from Prometec.");  // SMS Text
       Delay (100);
       SIM900.println ((char) 26);  // End command ^ Z
       Delay (100);
       SIM900.println ();
       Delay (5000);  // We wait for some time to send the SMS
       Serial.println ("Sent SMS");
    }