sim908_GPS_GSM_GPRS

/*This code has been developed by Francisco Caussa
 * Under Licence GPLv3
 * Th porpuse of this code is to work with any Arduino Board 
 * and a Sim908 GPS/GPRS/GSM Module
 * email: francisco.caussa@gmail.com
 *  
 * 
 */
 
 /*______________USAGE_______________
 *This code is intended to be used between Arduino (or similar boards) and SIM908 GPS/GPRS/GSM module.
 *You can modify the code to fit other MCU
 *it uses Serial AT commands so it can be adapted to fit almost any MCU with serial capabilities
 */
 
 
 /*___________WIRING________________
 *This code uses Software serial to talk between GPS/GSM/GPRS shield and MCU
 *Therefore Serial pins (0,1 on Arduino-Like boards) are unused, so you can debug with SerialMonitor
 *WARNING!
 *It requires hardware modifications on your shield.
 *You have to "BEND" pins 0,1 from shield so they no longer connect to the MCU board
 *And you have to wire those pins to the ones you will use on Software serial.
 *In this example, Software serial is defined on PINS 10 and 11.
 *You can change them to whatever you feel like.
 */
 
 
 /*This code has been modified several times.
 *It requires Software Serial and TimerOne libraries.
 *TimerOne Library ----->  https://github.com/PaulStoffregen/TimerOne Thank you Paul for your Library.
 *Software Serial ----> https://www.arduino.cc/en/Reference/SoftwareSerial


 
#include <SoftwareSerial.h>
#include <TimerOne.h>
SoftwareSerial sim908(10, 11); // RX, TX for debug porpouses

char latitude[15]; //latitude variable
char longitude[15]; //longitude Variable

char last_latitude[15]; //last latitude used to compare if location changed
char last_longitude[15]; //last longitude used to compare if location changed 


String inData; //Serial Buffer
char inDataCharArray[50];

boolean iguales = true; //Flag to compare if variables are the same

boolean validCode = false; //Flag to check is SMS code is valid to execute "something"

char msgSMS[20];
char msg2send[20];
char answer[20];

int inicioCodigo;
int v207;
boolean is207 = false;

int interruptCounter=0;  



void setup()
{
  //Init the driver pins for GSM function


  
  pinMode(3,OUTPUT);
  pinMode(4,OUTPUT);
  pinMode(5,OUTPUT);
  //Output GSM Timing 
  digitalWrite(5,HIGH);
  delay(1500);
  digitalWrite(5,LOW); 
  
  sim908.begin(9600);
  Serial.begin(9600);
  digitalWrite(3,LOW);//enable GSM TX、RX
  digitalWrite(4,HIGH);//disable GPS TX、RX

  delay(30000); //wait 30s for shield to initialize

  setTextModeSMS();

  delay(1000);

  start_GSM(); //set up GSM configuration

  delay(5000);

  start_GPS(); //set up and initialize GPS

  delay(2000);

  sim908.flush(); //clear whatever is left on serial.

  Timer1.initialize(1000000); // set a timer of length 1000000 microseconds (1 sec)
  Timer1.attachInterrupt( timerISR ); // attach the service routine here

  

}
void loop()    
{ 
  while(!(Serial.available()>0)){
    //do nothing until a serial SMS reaches or interrupt makes update GPS coordinates
  }
}

void start_GSM(){
  //Configuracion GPRS Claro Argentina
  sim908.println("AT");
  delay(2000);
  sim908.println("AT+CNMI=2,2,0,0,0");        // as soon as somethnig reaches the SIM908, will be sent throught serial to the Arduino
  delay(2000);
  sim908.println("AT+CREG?");
  delay(2000);
  sim908.println("AT+SAPBR=3,1,\"APN\",\"igprs.claro.com.ar\""); //APN
  delay(2000);
  sim908.println("AT+SAPBR=3,1,\"USER\",\"clarogprs\""); //user
  delay(2000);
  sim908.println("AT+SAPBR=3,1,\"PWD\",\"clarogprs999\""); //Pass
  delay(2000);
  sim908.println("AT+SAPBR=3,1,\"Contype\",\"GPRS\"");
  delay(2000);
  sim908.println("AT+SAPBR=1,1");
  delay(10000);
  sim908.println("AT+HTTPINIT");
  delay(2000);
  sim908.println("AT+HTTPPARA=\"CID\",1");
  delay(2000);
}

void send_GPRS(){

  sim908.print("AT+HTTPPARA=\"URL\",\"YOU_WEB_SERVER_URL_/.php?latitude="); 
  sim908.print(latitude);
  sim908.print("&longitude=");
  sim908.print(longitude);
  sim908.println("\"");
  delay(2000);
  sim908.println("AT+HTTPACTION=0"); //now GET action
  delay(2000);


}


void start_GPS(){
  //Configuracion en Inicializacion GPS
  sim908.print("AT");
  delay(1000);
  sim908.println("AT+CGPSIPR=9600");// (set the baud rate)
  delay(1000);
  sim908.println("AT+CGPSPWR=1"); // （turn on GPS power supply）
  delay(1000);
  sim908.println("AT+CGPSRST=1"); //（reset GPS in autonomy mode）
  delay(10000); //delay para esperar señal del GPS
}

void read_GPS(){

  sim908.println("AT+CGPSINF=0");

  read_String();
  inData.toCharArray(inDataCharArray,50);
  strtok(inDataCharArray, ",");
  strcpy(longitude,strtok(NULL, ",")); // Gets longitude
  strcpy(latitude,strtok(NULL, ",")); // Gets latitude


  DDMM2ddmm(latitude, "latitud"); //fix data
  DDMM2ddmm(longitude, "longitud"); //fix data


}


void read_String() { //function to read serial data and store it as string
  inData="";
  inData=sim908.readStringUntil('\n');
  Serial.print(inData); //Debug 
}


void DDMM2ddmm(char charArray[15], String flag){
  boolean negative = false;
  double DD;
  double MM;
  char dd[5];
  char mm[15];
  int index=0;
  int i=0;
  int j=0;
  int k=0;
  int dotposition;
  int nullcharcounter;
  boolean notadot=true;
  boolean notlenghtend=true;

  if(charArray[0]=='-'){
    negative=true;
    index=1;
  }

  while(notadot){
    if(charArray[index]=='.'){
      notadot=false;
    }
    else{
      index++;
    }
  }

  dotposition=index;



  if(negative){
    i=1;
  }
  else{
    i=0;
  }

  k=0;

  for(j=i; j<dotposition-2;j++){
    dd[k]=charArray[j];
    k++;
  }

  dd[k]='\0';

  index=(dotposition-2);
  mm[0]='0';
  mm[1]='.';
  mm[2]=charArray[index];
  mm[3]=charArray[index+1];

  index=(dotposition+1);

  k=0;
  nullcharcounter=0;

  while(notlenghtend){
    if(charArray[index]=='\0'){
      notlenghtend=false;
    }
    else{
      nullcharcounter++;
      index++;  
    }


  }
  index=(dotposition+1);

  for(k=0;k<nullcharcounter;k++){
    mm[k+4]=charArray[index+k];
  }
  mm[k+5]='\0';

  DD=atof(dd);
  if(negative){
    DD=DD*(-1);
  }

  MM=atof(mm);

  MM=100*MM/60;

  if(negative){
    MM=MM*(-1); 
  }

  DD=DD+MM; //re arrange variable


  if(flag=="latitud"){

    dtostrf(DD,5,6,latitude); //write lattitude into variable to be sent
  }

  if(flag=="longitud"){

    dtostrf(DD,5,6,longitude); //write longitude into variable to be sent
  }
}

void setTextModeSMS(){
  sim908.println("AT+CMGF=1"); //Set to Text Mode
  delay(1000);
  deleteALL(); //erase all messages
}



void readSMS() {
    inicioCodigo=inData.indexOf("P"); //find the position of letter P. since valid code begins as P207 
    if(inicioCodigo>0){
      if(inData.substring(inicioCodigo+1,inicioCodigo+3)=="207"){
        //then, there is a valid code on the message!
        validCode=true; 
      }       
  } //Now, go DECODE IT!
  if(validCode){
    decodeMSG;
  }
  else{
   sendSMS("Error! Codigo no verificado!"); //Error message as the SMS did not contiain a valid code
  }

}

void deleteALL() {
  sim908.println("AT+CMGD=1,4"); //deletes all SMS 
  delay(1000);
}

void sendSMS(char message[20]) {
  strcpy(msg2send,message);
  sim908.println("AT+CMGF=1"); //sets to text mode
  delay(1000);
  sim908.println("AT+CMGS=\"+YOUR_PHONE_NUMBER\""); //sets phone number to send SMS
  delay(1000);
  sim908.print(msg2send); //prints message to SIM908
  delay(1000);
  sim908.write(26); // (ascii)Ctrl+Z sends message
  deleteALL();
}

void decodeMSG(){ //decode what SMS contains and return answer form module
//inicioCodigo+5 es donde comienza el codigo, despues de "P207 " donde P es la posicion 0;
 if(inData.substring(inicioCodigo+5,inicioCodigo+10)=="alarma"){
   sendSMS("Alarma ON"); //instruction to execute if keyword is "alarma"
 }else if(inData.substring(inicioCodigo+5,inicioCodigo+13)=="ubicacion"){
  sendSMS("Ubicacion");//instruction to execute if keyword is "ubicacion"
 }else if(inData.substring(inicioCodigo+5,inicioCodigo+10)=="apagar"){
 sendSMS("Apagado");//instruction to execute if keyword is "alarma"
 } else{ //default, this is the set of intruction to execute if there is no a valid code!
 sendSMS("Error! Codigo desconocido!"); //Error, unkown instruction
 }
 validCode=false;
}

void updateLocation(){ //update location routine
  int i=0;
   for(i=0;i<=15;i++){
   last_latitude[i]=latitude[i];
   last_longitude[i]=longitude[i];
   }
   read_GPS();
   delay(2000);
   
   
   i=0;
   for(i=0;i<15;i++){
     if(last_latitude[i] == latitude[i] && last_longitude[i] == longitude[i]) //if its not the same location, update!
     {
       iguales = true;
     }
     else{
       iguales = false;
       break;
       }
   }
   
   if(iguales==false){
     send_GPRS();
     delay(5000);
   }
}


void timerISR(){
  if(interruptCounter>60){ //If a minute has passed
    updateLocation();
    interruptCounter=0;
    }else{
    interruptCounter++;
    }  
  }