Wireless Notice Board Using GSM and Arduino

Wireless notice board is very selective term for this project, as it has a very wide scope rather than just being a simple notice board. First we should understand the purpose of this project, in this system we can display a message or notice to some display device like LCD, and this message can be easily set or changed from anywhere in the world, just by using the SMS facility of your mobile handset. Whatever notice we want to display, just send the SMS of that text, with some prefix and suffix.

 

This is very useful in Hotels, Malls, college, offices and can be used anywhere, even at home. Like you can set the message like “Do not disturb” at your hotel’s room gate, can set message at your home’s door step when you are away, and of course it is used as notice board in schools, colleges, cinema halls etc. And yes, it’s just not a simple Message board, the usefulness of this project is that you can set or change the message or notice from anywhere, just sending SMS from your phone.

 

We have previously used the SMS facility of mobile phone for home security and control the home appliances remotely: PIR Sensor and GSM Based Security System and GSM Based Home Automation using Arduino

Working Explanation:

In this project, Arduino UNO is used for controlling the whole process, GSM module (SIM900A) to receive the SMS/message sent from mobile phone and LCD to display the message.

GSM Arduino and LCD for wireless notice board

We can send some message or notice like “#Circuit Digest*”, “#We Welcomes You*” through the SMS. Here we have used a prefix in the message string that is ‘#’. This prefix is used to identify the starting of the message or notice. And ‘*’ is used as suffix to indicate the end of the message or notice.

 

When we send SMS from mobile phone to GSM module then GSM receives that SMS and sends it to Arduino. Now Arduino read this SMS and extract main notice message from the received string and stores in another string.  And then sends the extracted message to 16x2 LCD by using appropriate commands.

Wireless Notice Board Using GSM Block-diagram

Further working of this system is explained in the ‘Code Description’ section below. Before we get into programming details we should know about GSM module.

GSM Module:

GSM module is used in many communication devices which are based on GSM (Global System for Mobile Communications) technology. It is used to interact with GSM network using a computer. GSM module only understands AT commands, and can respond accordingly. The most basic command is “AT”, if GSM respond OK then it is working good otherwise it respond with “ERROR”. There are various AT commands like ATA for answer a call, ATD to dial a call, AT+CMGR to read the message, AT+CMGS to send the sms etc. AT commands should be followed by Carriage return i.e. \r (0D in hex), like “AT+CMGS\r”. We can use GSM module using these commands:

ATE0 For echo off

AT+CNMI=2,2,0,0,0  <ENTER>           Auto opened message Receiving.  (No need to open message)

ATD<Mobile Number>; <ENTER>      making a call (ATD+919610126059;\r\n)

AT+CMGF=1 <ENTER>                        Selecting Text mode

AT+CMGS=”Mobile Number” <ENTER>  Assigning recipient’s mobile number

>>Now we can write our message

>>After writing message

Ctrl+Z  send message command (26 in decimal).

ENTER=0x0d in HEX

GSM-Module-SIM900A

The SIM900 is a complete Quad-band GSM/GPRS Module which delivers GSM/GPRS 850/900/1800/1900MHz performance for voice, SMS and Data with low power consumption.

 

Circuit Description:

Connections of Wireless Notice Board using GSM and Arduino are simple and shown in the figure below. Here a liquid crystal display (LCD) is used for display the “Notice” or message, which is sent though the mobile phone as SMS. Data pins of LCD namely RS, EN, D4, D5, D6, D7 are connected to arduino digital pin number 7, 6, 5, 4, 3, 2. And Rx and Tx pin of GSM module is directly connected at Tx and Rx pin of Arduino respectively. And GSM module is powered by using a 12 volt adaptor.

Wireless Notice Board using GSM circuit diagram

Code Description:

The code of the program is easily understandable; the new thing here is GSN initialization function gsm_init(), which is explained in the end.

In the program, first of all we include library for liquid crystal display (LCD) and then we defines data and control pins for LCD and some variables.

#include <LiquidCrystal.h>
LiquidCrystal lcd(7,6,5,4,3,2);

int led=13;

int temp=0,i=0,x=0,k=0;
char str[100],msg[32];

After this, serial communication is initialized at 9600 bps and gives direction to used pin. And initialize GSM Module in setup loop.

void setup() 
{
  lcd.begin(16,2);
  Serial.begin(9600);
  pinMode(led, OUTPUT);
  digitalWrite(led, HIGH);
  lcd.print("GSM Initilizing...");
  gsm_init();
  lcd.setCursor(0,0);
  lcd.print("Wireless Notice");

 For receiving data serially we use two functions, one is Serial.available which checks any serial data is coming or not and other one is Serial.read which reads the data that comes serially.

void serialEvent()
{
  while(Serial.available())
  {
    char ch=(char)Serial.read();
    str[i++]=ch;
    if(ch == '*')
    {
      temp=1;
      lcd.clear();
      lcd.print("Message Received");
      delay(1000);
    }
  }
}

After receiving data serially, we store it in a string and this string is checked for ‘#’ and ‘*’, to find the starting and ending of the Notice or message. Then finally Notice is printed on LCD using lcd.print:

void loop()    
{
  for(unsigned int t=0;t<60000;t++)
  {
    serialEvent();
  if(temp==1)
  {
    x=0,k=0,temp=0;
    while(x<i)
    {
      while(str[x]=='#')
      {
        x++;
        while(str[x]!='*')
        {
          msg[k++]=str[x++];

Initialization function ‘gsm_init()’ for GSM is important here, where firstly, GSM module is checked whether it is connected or not by sending ‘AT’ command to GSM module. If response OK is received, means it is ready. System keeps checking for the module until it becomes ready or until ‘OK’ is received. Then ECHO is turned off by sending the ATE0 command, otherwise GSM module will echo all the commands. Then finally Network availability is checked through the ‘AT+CPIN?’ command, if inserted card is SIM card and PIN is present, it gives the response +CPIN: READY. This is also check repeatedly until the network is found. This can be clearly understood by the Video below.

void gsm_init()
{
  lcd.clear();
  lcd.print("Finding Module..");
  boolean at_flag=1;
  while(at_flag)
  {
    Serial.println("AT");
    while(Serial.available()>0)
    {
      if(Serial.find("OK"))
      at_flag=0;
    }
    delay(1000);
  }
Code: 

#include <LiquidCrystal.h>
LiquidCrystal lcd(7,6,5,4,3,2);

int led=13;

int temp=0,i=0,x=0,k=0;
char str[100],msg[32];

void setup() 
{
  lcd.begin(16,2);
  Serial.begin(9600);
  pinMode(led, OUTPUT);
  digitalWrite(led, HIGH);
  lcd.print("GSM Initilizing...");
  gsm_init();
  lcd.setCursor(0,0);
  lcd.print("Wireless Notice");
  lcd.setCursor(0,1);
  lcd.print("    Board      ");
  delay(2000);
  lcd.clear();
  lcd.print("Circuit Digest");
  delay(1000);
  lcd.setCursor(0,1);
  lcd.print("System Ready");
  Serial.println("AT+CNMI=2,2,0,0,0");
  delay(500);
  Serial.println("AT+CMGF=1");
  delay(1000);
  digitalWrite(led, LOW);
}

void loop()    
{
  for(unsigned int t=0;t<60000;t++)
  {
    serialEvent();
  if(temp==1)
  {
    x=0,k=0,temp=0;
    while(x<i)
    {
      while(str[x]=='#')
      {
        x++;
        while(str[x]!='*')
        {
          msg[k++]=str[x++];
        }
      }
      x++;
    }
    msg[k]='\0';
    lcd.clear();
    lcd.print(msg);
    delay(1000);
    temp=0;
    i=0;
    x=0;
    k=0;
  }
  }
  lcd.scrollDisplayLeft();
}
void serialEvent()
{
  while(Serial.available())
  {
    char ch=(char)Serial.read();
    str[i++]=ch;
    if(ch == '*')
    {
      temp=1;
      lcd.clear();
      lcd.print("Message Received");
      delay(1000);
    }
  }
}

void gsm_init()
{
  lcd.clear();
  lcd.print("Finding Module..");
  boolean at_flag=1;
  while(at_flag)
  {
    Serial.println("AT");
    while(Serial.available()>0)
    {
      if(Serial.find("OK"))
      at_flag=0;
    }
    delay(1000);
  }

  lcd.clear();
  lcd.print("Module Connected..");
  delay(1000);
  lcd.clear();
  lcd.print("Disabling ECHO");
  boolean echo_flag=1;
  while(echo_flag)
  {
    Serial.println("ATE0");
    while(Serial.available()>0)
    {
      if(Serial.find("OK"))
      echo_flag=0;
    }
    delay(1000);
  }

  lcd.clear();
  lcd.print("Echo OFF");
  delay(1000);
  lcd.clear();
  lcd.print("Finding Network..");
  boolean net_flag=1;
  while(net_flag)
  {
    Serial.println("AT+CPIN?");
    while(Serial.available()>0)
    {
      if(Serial.find("+CPIN: READY"))
      net_flag=0;
    }
    delay(1000);
  }
  lcd.clear();
  lcd.print("Network Found..");
  delay(1000);
  lcd.clear();
}

Video: 

Comments (40)

  • Graham's picture
    Graham

    Thanks a ton, this is one of the few examples of RECEIVING a SMS that work, there are zillions of ones for sending but so few like yours

    Jan 26, 2016
  • saddam khan's picture
    saddam khan

    Thank Buddy..

    Jan 27, 2016
  • sachin's picture
    sachin

    GSM receiving the message and showing on serial monitor but not displaying on LCD . What may be the reason???

    Feb 15, 2016
  • Vivek's picture
    Vivek

    Have you fixed your circuit in PCB???

    Nov 28, 2016
  • Abhishek's picture
    Abhishek

    Check circuit connections and code.

    Feb 23, 2016
  • PRINCE SANGWAN's picture
    PRINCE SANGWAN

    how would i intialise the the gsm module after writing the code in arduino, like how would i write those AT commands in gsm module?and would u mind sharing ur mail id for further communication?

    Feb 05, 2016
  • saddam khan's picture
    saddam khan

    saddam4201 at gmail.com

    Feb 07, 2016
  • sachin's picture
    sachin

    The above code after some modification is able to receive message and display it on serial monitor but not on LCD display please help me. your email id is not correct.

    Feb 29, 2016
  • sachin's picture
    sachin

    I have modified the code attached because initially it wasn’t working.
    Still it is not working i.e. the message send through gsm module is not displaying on LCD but it showing on the serial monitor.
    Is there any problem in reading data serially and displaying??
    According to your code the string is in # and *???
    Please help me out….
    Resolve the issue.

    Feb 29, 2016
  • Maddy's picture
    Maddy

    yes, string is in # and *. The code and circuit diagram are correct, please cross check them twice. Check you LCD, whether it is working properly. What are you getting on LCD.

    Mar 11, 2016
  • SoloDE's picture
    SoloDE

    what program do you use to draw your circuit diagram ?
    thank you

    Mar 02, 2016
  • Maddy's picture
    Maddy

    Proteus with Arduino Library installed.

    Mar 11, 2016
  • Rey's picture
    Rey

    can you please help me design a circuit diagram for an a Wireless Notice Board using Arduino Uno and GSM?

    Apr 08, 2016
  • shaikshavez's picture
    shaikshavez

    I truly appreciate your work, you have really helped me like anything. Thanks for this bro.!!

    Mar 24, 2016
  • shambel wondimnew's picture
    shambel wondimnew

    dear pleas send me the full document for this project that i need to do the same project to my company

    Apr 09, 2016
  • Paul Bradfield's picture
    Paul Bradfield

    Interesting reading. I want to setup wireless notice board using SMS. Can I just use a tablet to receive TXt's with a sim, instead of a GSM module & just adapt the tablet to read more as a noticeboard ?

    Apr 20, 2016
  • Abhishek's picture
    Abhishek

    You can use Tablet in place of Mobile Phone.

    May 06, 2016
  • SOHEL's picture
    SOHEL

    can i use Bengali language in LCD display. Please help.

    Jun 15, 2016
  • rahul kapoor's picture
    rahul kapoor

    sir,dont we need to set baud rate to 2400 as SIM900A does not work with 9600 baud rate.

    Jun 25, 2016
  • abi's picture
    abi

    please attach the correct coding for us pls

    Jul 20, 2016
  • saddam khan's picture
    saddam khan

    Code is tested you may go ahead with the same given on the website....

    best of luck

    Jul 25, 2016
  • Udaykiran Reddy's picture
    Udaykiran Reddy

    i have used arduino mega 2560 & GSM 800,do i have to change any part of the code as i was not able to display message.

    Jul 28, 2016
  • Tim's picture
    Tim

    Thanks for a brilliant tutorial, nice and easy to follow. Mine does however refuse to display long messages (I would like to display about 30/40 words) but when I try this it either freezes/doesn't display any text at all or reboots by running through the GSM initializing, ECHO off and etc. How do I get it to recieve and display longer messages?
    Thanks in advance :)

    Aug 03, 2016
  • Maddy's picture
    Maddy

    You can display long messages by using the given program itself, it is using lcd.scrollDisplayLeft(); function for scrolling the long messages. I think there may be some problem in your hardwares.

    Aug 20, 2016
  • Muhammad Usman's picture
    Muhammad Usman

    I don't know how to Thank you You really made my day...
    May you get more & more success.

    Sep 07, 2016
  • harish 's picture
    harish

    nice

    Sep 09, 2016
  • NDEBELE's picture
    NDEBELE

    the code just jumps to Finding module, and nothing else, may you please send me one that works well.

    Oct 18, 2016
  • Akshay yadav's picture
    Akshay yadav

    i m also getting the same problem ,the code just jumps to Finding module, and nothing else, may you please send me one that works well.

    Oct 27, 2016
  • Abhishek's picture
    Abhishek

    It is the problem related to GSM Module, try to just connect GSM module and send AT command and then check whether your GSM responds with OK. Use serial monitor to check the response.

    Nov 30, 2016
  • usman's picture
    usman

    hello sir!iam using gsm 800L.everything is ok but msg is not getting receoved and displayed on the lcd.

    Nov 17, 2016
  • curious's picture
    curious

    is there something bigger than that 16*2 LCD sir/ma'am? something that can be used for larger establishments? grateful if you notice me.

    Nov 19, 2016
  • usman's picture
    usman

    no its16*2 lcd display,by the way iam sir :)

    Nov 24, 2016
  • Emdaddul Bari Fahad's picture
    Emdaddul Bari Fahad

    All term has complete & shown in display, but it doesn't work for sending massese. How can i send SMS? and how can it displayed??.........Please help me...............

    Dec 07, 2016
  • Rose Edillo's picture
    Rose Edillo

    Is there a way to extend the 32 character limit displayed still using the 16x2 lcd?

    Dec 13, 2016
  • usman's picture
    usman

    it worked! i have changed the pins to pin no 10 and 11 and it worked and a little bit change in the code.

    Dec 19, 2016
  • naveenkumar's picture
    naveenkumar

    insert a buzzer to this project and this buzzer is on when message is received by the gsm module

    Jan 06, 2017
  • Sanket's picture
    Sanket

    Sir I have setup all the connections like yours but i only have the problem with the gsm module yhat it indicate "Finding Module.." on LCD display. Please Sir caan you please solve my problem...

    Jan 16, 2017

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