Arduino IoT Tutorial 6 – Send an SMS using GSM

Components Required:

1. Arduino Uno 

2. Linux PC/Windows PC (Tested with Windows 10, Ubuntu 14.04 LTS)

3. USB cable A to B 

4.  SIM800L GSM Module 

5. 12V 1A Adapter (if you are using SIM900A GSM Modem)

6. SIM Card

7. Jumper Wires

Way to go ->

1. Connect Arduino Uno to PC via the USB cable.

2. Upload SMS.ino to the Arduino.

SMS.ino

#include <SoftwareSerial.h>

SoftwareSerial mySerial(10, 11); // (Rx, Tx)

void setup()

{

  mySerial.begin(9600);   // Setting the baud rate of GSM Module

  Serial.begin(9600);    // Setting the baud rate of Serial Monitor (Arduino)

  delay(100);

}

void loop()

{

  if (Serial.available() > 0)

    switch (Serial.read())

    {

      case 's':

        SendMessage();

        break;

      case 'r':

        RecieveMessage();

        break;

    }

  if (mySerial.available() > 0)

    Serial.write(mySerial.read());

}

void SendMessage()

{

  mySerial.println("AT+CMGF=1");    //Sets the GSM Module in Text Mode

  delay(1000);  // Delay of 1000 milli seconds or 1 second

  mySerial.println("AT+CMGS=\"+91xxxxxxxxxx\"\r"); // Replace x with mobile number

  delay(1000);

  mySerial.println("I am SMS from GSM Module");// The SMS text you want to send

  delay(100);

  mySerial.println((char)26);// ASCII code of CTRL+Z

  delay(1000);

}

void RecieveMessage()

{

  mySerial.println("AT+CNMI=2,2,0,0,0"); // AT Command to receive a live SMS

  delay(1000);

}

4. In the empty box at the top of the serial monitor type -> s, and click Send to send an SMS.

Hardware Connections ->

1. GSM Module to Arduino Uno