Hello everyone,
I am using the code below for my sim808 gsm/gprs and gps module to get gps location and send at text every 20seconds. Unfortunately the gps outputs the correct value the first time the operation is performed then the next time it merges the former values with the new values in serial monitor which makes the coordinate incorrect. Any suggestion on how to fix it
#include <SoftwareSerial.h>
SoftwareSerial sim808(7,8);
char phone_no[] = “xxxxxxx”; // replace with your phone no.
String data[5];
#define DEBUG true
String state,timegps,latitude,longitude;
void setup() {
sim808.begin(9600);
Serial.begin(9600);
delay(50);
sim808.print(“AT+CSMP=17,167,0,0”); // set this parameter if empty SMS received
delay(100);
sim808.print(“AT+CMGF=1\r”);
delay(400);
sendData(“AT+CGNSPWR=1”,1000,DEBUG);
delay(50);
sendData(“AT+CGNSSEQ=RMC”,1000,DEBUG);
delay(150);
}
void loop() {
sendTabData(“AT+CGNSINF”,1000,DEBUG);
if (state !=0) {
Serial.println(“State :”+state);
Serial.println(“Time :”+timegps);
Serial.println(“Latitude :”+latitude);
Serial.println(“Longitude :”+longitude);
sim808.print(“AT+CMGS=\””);
sim808.print(phone_no);
sim808.println(“\””);
delay(300);
sim808.print(“[http://maps.google.com/maps?q=loc:”);](http://maps.google.com/maps?q=loc:%22);)
sim808.print(latitude);
sim808.print(“,”);
sim808.print (longitude);
delay(200);
sim808.println((char)26); // End AT command with a ^Z, ASCII code 26
delay(200);
sim808.println();
delay(20000);
sim808.flush();
} else {
Serial.println(“GPS Initializing…”);
}
}
void sendTabData(String command , const int timeout , boolean debug){
sim808.println(command);
long int time = millis();
int i = 0;
while((time+timeout) > millis()){
while(sim808.available()){
char c = sim808.read();
if (c != ‘,’) {
data[i] +=c;
delay(100);
} else {
i++;
}
if (i == 5) {
delay(100);
goto exitL;
}
}
}exitL:
if (debug) {
state = data[1];
timegps = data[2];
latitude = data[3];
longitude =data[4];
}
}
String sendData (String command , const int timeout ,boolean debug){
String response = “”;
sim808.println(command);
long int time = millis();
int i = 0;
while ( (time+timeout ) > millis()){
while (sim808.available()){
char c = sim808.read();
response +=c;
}
}
if (debug) {
Serial.print(response);
}
return response;
}