Data generated in incorrect manner

akshaypowar · March 23, 2023, 3:50pm

Hello Guys,
For my project I am using 3 gps modules(Neo6m gps module) with arduino mega 2560 and I want to get measurements from them every 1 second that is 1st gps will give 1st reading after 1 sec 2nd gps will give 2nd reading and then after 1 sec 3rd gps will give 3rd reading. Again 1st gps will give 4th reading 2nd will give 5th and 3rd will give 6th reading with 1 sec interval. But I am getting the readings not in correct sequence also the time shown in the .txt file is not correct either.
Here is my code

#include "SD.h"
#include <SPI.h>
#include <TinyGPS++.h>


TinyGPSPlus gps1,gps2,gps3;

String  day, month, year, hour, minute, second, Date, Time, Data;
double Latitude, Longitude, Altitude;
String gps_1 = "GPS1", gps_2 = "GPS2", gps_3 = "GPS3";
String filename = "GPSLOG";


void setup() {
  Serial.begin(9600);
  Serial.print("Initializing SD card...");

  if (!SD.begin(53)) {
    Serial.println("initialization failed!");
    while (1);
  }
  Serial.println("initialization done.");
  
  int count = 0;
  bool flag = false;

  while(!flag){
    if(SD.exists(filename + ".txt")){
      count++;
      filename = "GPSLOG" + (String)count;
      Serial.print(filename);
    }else{
      flag = true;
    }
  } 
  File myFile = SD.open((filename+".txt"), FILE_WRITE);
  if (myFile) {
    myFile.println( "GPS, Latitude, Longitude, Date and Time \r\n");
    myFile.close();

  } else {
    Serial.println("error opening GPS_data.txt");
  }
 Serial1.begin(9600);
 Serial2.begin(9600);
 Serial3.begin(9600);
}

void loop() {
  if (Serial1.available() > 0){
    if (gps1.encode(Serial1.read())){
      obtain_data(gps1,gps_1,filename);        
    }
      
  }
  if (Serial2.available() > 0){
    if (gps2.encode(Serial2.read())){
      obtain_data(gps2,gps_2, filename);
    }
      
  }
  if (Serial3.available() > 0){
    if (gps3.encode(Serial3.read())){
      obtain_data(gps3,gps_3, filename);
    }
      
  }
  if (millis() > 10000 && gps1.charsProcessed() < 10 && gps2.charsProcessed() < 10 && gps3.charsProcessed() < 10)
  {
    Serial.println("GPS NOT DETECTED!");
    while(true);
  }

}

void obtain_data(TinyGPSPlus gps, String sensor, String filename)
{
  if (gps.location.isValid())
  {
    Latitude = gps.location.lat();
    Longitude = gps.location.lng();
    Altitude = gps.altitude.meters();
    //File myFile = SD.open((filename+".txt"), FILE_WRITE);
  }
  else
  {
    Serial.println("Location is not available");
  }
  
  if (gps.date.isValid())
  {
    month = gps.date.month();
    day = gps.date.day();
    year = gps.date.year();
    Date = day + "-" + month + "-" + year;
     Serial.println(Date);
  }
  else
  {
    Serial.print("Date Not Available");
  }
 
  Serial.print("Time: ");
  if (gps.time.isValid())
  {
    //if (gps.time.hour() < 10) ;
    hour = gps.time.hour();
    //if (gps.time.minute() < 10);
    minute = gps.time.minute();
    //if (gps.time.second() < 10) ;
    second = gps.time.second();
    Time = hour + ":" + minute + ":" + second;
  Serial.println(Time);
  }
  else
  {
    Serial.print("Time Not Available");
  }
  
  Data = sensor + "," + (String)Latitude + "," + (String)Longitude + "," + (String)Altitude + "," + Date + "," + Time;
  Serial.print("Save data: ");
  Serial.println(Data);
  File myFile = SD.open((filename+".txt"), FILE_WRITE);

  if (myFile) {
    Serial.print("GPS logging to " + filename+".txt"+"...");
    //myFile.print(Data);
    myFile.print(sensor);
    myFile.print(",");
    myFile.print(gps.location.lat(),6);
    myFile.print(",");
    myFile.print(gps.location.lng(),6);
    myFile.print(",");
    myFile.print(gps.altitude.meters(),3);
    myFile.print(",");
    myFile.print(Date+","+Time);
    myFile.println("");    
    myFile.close();
    Serial.println("done.");
  } else {
    Serial.println("error opening GPS_data.txt");
  } 
 Serial.println();
 delay(1000);
}

and here is my data in the .txt file

GPS, Latitude, Longitude, Date and Time 

GPS3,0.000000,0.000000,0.000,,
GPS2,0.000000,0.000000,0.000,,
GPS1,0.000000,0.000000,0.000,,
GPS3,0.000000,0.000000,0.000,,
GPS1,0.000000,0.000000,0.000,,
GPS2,0.000000,0.000000,0.000,,
GPS3,0.000000,0.000000,0.000,,
GPS3,48.780967,11.475488,0.000,23-3-2023,14:39:50
GPS2,48.781017,11.475526,0.000,23-3-2023,14:39:50
GPS1,48.780933,11.475433,0.000,23-3-2023,14:39:50
GPS3,48.780967,11.475488,0.000,23-3-2023,14:39:50
GPS2,48.781017,11.475526,0.000,23-3-2023,14:39:50
GPS1,48.780933,11.475433,0.000,23-3-2023,14:39:50
GPS1,48.780933,11.475433,0.000,23-3-2023,14:39:50
GPS2,48.781017,11.475526,0.000,23-3-2023,14:39:50
GPS3,48.780975,11.475486,0.000,23-3-2023,14:39:59
GPS2,48.781013,11.475529,0.000,23-3-2023,14:39:59
GPS1,48.780948,11.475444,0.000,23-3-2023,14:39:59
GPS3,48.780975,11.475486,0.000,23-3-2023,14:39:59
GPS2,48.781013,11.475529,0.000,23-3-2023,14:39:59
GPS1,48.780948,11.475444,0.000,23-3-2023,14:39:59
GPS1,48.780948,11.475444,0.000,23-3-2023,14:39:59
GPS3,48.780975,11.475500,0.000,23-3-2023,14:40:7
GPS2,48.781013,11.475537,0.000,23-3-2023,14:40:7
GPS1,48.780952,11.475448,0.000,23-3-2023,14:40:7
GPS3,48.780975,11.475500,0.000,23-3-2023,14:40:7
GPS2,48.781013,11.475537,0.000,23-3-2023,14:40:7
GPS1,48.780952,11.475448,0.000,23-3-2023,14:40:7
GPS3,48.780975,11.475500,0.000,23-3-2023,14:40:7
GPS2,48.781013,11.475537,0.000,23-3-2023,14:40:7
GPS1,48.780952,11.475448,0.000,23-3-2023,14:40:7
GPS3,48.781013,11.475542,0.000,23-3-2023,14:40:17
GPS2,48.781044,11.475566,0.000,23-3-2023,14:40:17
GPS1,48.780990,11.475477,0.000,23-3-2023,14:40:17
GPS3,48.781013,11.475542,0.000,23-3-2023,14:40:17
GPS2,48.781044,11.475566,0.000,23-3-2023,14:40:17
GPS1,48.780990,11.475477,0.000,23-3-2023,14:40:17
GPS2,48.781044,11.475566,0.000,23-3-2023,14:40:17
GPS2,48.781127,11.475605,0.000,23-3-2023,14:40:25
GPS3,48.781089,11.475604,0.000,23-3-2023,14:40:25
GPS1,48.781059,11.475521,0.000,23-3-2023,14:40:25
GPS2,48.781127,11.475605,0.000,23-3-2023,14:40:25
GPS3,48.781089,11.475604,0.000,23-3-2023,14:40:25
GPS1,48.781059,11.475521,0.000,23-3-2023,14:40:25
GPS1,48.781059,11.475521,0.000,23-3-2023,14:40:25
GPS2,48.781127,11.475605,0.000,23-3-2023,14:40:25
GPS3,48.781177,11.475682,0.000,23-3-2023,14:40:34
GPS2,48.781219,11.475651,0.000,23-3-2023,14:40:34
GPS1,48.781139,11.475566,0.000,23-3-2023,14:40:34
GPS3,48.781177,11.475682,0.000,23-3-2023,14:40:34
GPS2,48.781219,11.475651,0.000,23-3-2023,14:40:34
GPS1,48.781139,11.475566,0.000,23-3-2023,14:40:34
GPS3,48.781177,11.475682,0.000,23-3-2023,14:40:34
GPS1,48.781139,11.475566,0.000,23-3-2023,14:40:34
GPS2,48.781219,11.475651,0.000,23-3-2023,14:40:34
GPS3,48.781299,11.475773,0.000,23-3-2023,14:40:44
GPS2,48.781341,11.475717,0.000,23-3-2023,14:40:44
GPS1,48.781257,11.475636,0.000,23-3-2023,14:40:44
GPS3,48.781299,11.475773,0.000,23-3-2023,14:40:44
GPS2,48.781341,11.475717,0.000,23-3-2023,14:40:44
GPS1,48.781257,11.475636,0.000,23-3-2023,14:40:44
GPS3,48.781299,11.475773,0.000,23-3-2023,14:40:44
GPS1,48.781257,11.475636,0.000,23-3-2023,14:40:44
GPS2,48.781341,11.475717,0.000,23-3-2023,14:40:44
GPS3,48.781433,11.475853,0.000,23-3-2023,14:40:54
GPS2,48.781475,11.475785,0.000,23-3-2023,14:40:54
GPS1,48.781372,11.475707,0.000,23-3-2023,14:40:54
GPS3,48.781433,11.475853,0.000,23-3-2023,14:40:54
GPS2,48.781475,11.475785,0.000,23-3-2023,14:40:54
GPS1,48.781372,11.475707,0.000,23-3-2023,14:40:54
GPS3,48.781433,11.475853,0.000,23-3-2023,14:40:54
GPS1,48.781372,11.475707,0.000,23-3-2023,14:40:54
GPS2,48.781475,11.475785,0.000,23-3-2023,14:40:54
GPS3,48.781562,11.475852,0.000,23-3-2023,14:41:4
GPS2,48.781612,11.475845,0.000,23-3-2023,14:41:4
GPS1,48.781509,11.475793,0.000,23-3-2023,14:41:4
GPS3,48.781562,11.475852,0.000,23-3-2023,14:41:4
GPS2,48.781612,11.475845,0.000,23-3-2023,14:41:4
GPS1,48.781509,11.475793,0.000,23-3-2023,14:41:4
GPS2,48.781612,11.475845,0.000,23-3-2023,14:41:4
GPS3,48.781562,11.475852,0.000,23-3-2023,14:41:4
GPS1,48.781509,11.475793,0.000,23-3-2023,14:41:4
GPS3,48.781627,11.475646,0.000,23-3-2023,14:41:14
GPS2,48.781650,11.475724,0.000,23-3-2023,14:41:14
GPS1,48.781585,11.475650,0.000,23-3-2023,14:41:14
GPS3,48.781627,11.475646,0.000,23-3-2023,14:41:14
GPS2,48.781650,11.475724,0.000,23-3-2023,14:41:14
GPS1,48.781585,11.475650,0.000,23-3-2023,14:41:14
GPS3,48.781627,11.475646,0.000,23-3-2023,14:41:14
GPS2,48.781650,11.475724,0.000,23-3-2023,14:41:14
GPS1,48.781585,11.475650,0.000,23-3-2023,14:41:14
GPS3,48.781627,11.475646,0.000,23-3-2023,14:41:14
GPS2,48.781650,11.475724,0.000,23-3-2023,14:41:14
GPS1,48.781585,11.475650,0.000,23-3-2023,14:41:14
GPS3,48.781707,11.475388,0.000,23-3-2023,14:41:27
GPS2,48.781707,11.475461,0.000,23-3-2023,14:41:27
GPS1,48.781681,11.475405,0.000,23-3-2023,14:41:27
GPS3,48.781707,11.475388,0.000,23-3-2023,14:41:27
GPS2,48.781707,11.475461,0.000,23-3-2023,14:41:27
GPS1,48.781681,11.475405,0.000,23-3-2023,14:41:27
GPS3,48.781707,11.475388,0.000,23-3-2023,14:41:27
GPS1,48.781681,11.475405,0.000,23-3-2023,14:41:27
GPS2,48.781707,11.475461,0.000,23-3-2023,14:41:27
GPS3,48.781707,11.475388,0.000,23-3-2023,14:41:27
GPS1,48.781681,11.475405,0.000,23-3-2023,14:41:27
GPS3,48.781730,11.475377,0.000,23-3-2023,14:41:39
GPS2,48.781707,11.475389,0.000,23-3-2023,14:41:39
GPS1,48.781688,11.475375,0.000,23-3-2023,14:41:39
GPS3,48.781730,11.475377,0.000,23-3-2023,14:41:39
GPS2,48.781707,11.475389,0.000,23-3-2023,14:41:39
GPS1,48.781688,11.475375,0.000,23-3-2023,14:41:39
GPS3,48.781730,11.475377,0.000,23-3-2023,14:41:39
GPS1,48.781688,11.475375,0.000,23-3-2023,14:41:39

madmark2150 · March 23, 2023, 4:15pm

You're reading them as the data comes available instead of sequentially.

akshaypowar · March 23, 2023, 7:18pm

So does this mean there are no errors in code and generated data?

system · September 19, 2023, 7:19pm

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.

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Data generated in incorrect manner

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