Temperature and Humidity Logger Per Hour

/*  Humidity and Temperature Logger
 * 
 * Logging the humidity and temperature  per 1 hour
 *  while taking samples every 15 minutes and
 *  get the averege hunidity and temperature by dividing
 *  them with the count of samples it got.
 *  
 *  The first reading is from 
 *  the start up and gets refreshed
 *  every 15 minutes.
 * 
 * 
 *  Using the timeLib we count how many hours 
 *  it runs. 
 *  If we add an rtc we can have the real
 *  time of the time the variable logged.
 *  
 * 
 * The sd  pin out conection:
 * SD SCK : PIN 13
 * SD MISO : PIN 12
 * SD MOSI : PIN 11
 * SD CS : PIN 10
 * 
 * 
 * The lcd conection:
 * RS : PIN 9
 * ENABLE : PIN 8
 * LCD D4 : 7
 * LCD D5 : 6
 * LCD D6 : 5
 * LCD D7 : 4
 * 
 * The DHT conection:
 * DHT : PIN 2
 * 
 * 
 * Created 19/2/2019
 * by Lefteris X.
 */
///////////////////////TIME//////////////////////////////////////

#include "TimeLib.h"

unsigned long lastnow=0; // LAST TIME WRITED IN SD CARD

unsigned long lastSample=0; // LAST SAMPLE TAKEN

////////////////////////////////////////////////////////////////
  
///////////////////////////SD CARD/////////////////////////

  #include <SPI.h>
  #include <SD.h>

  const int chipSelect = 10;

  // make a string for assembling the data to log:
  String dataString = "";  
  String time = "";
  
  int lastWrite=0; // COUNT THE HOURS LOGGED
  
  float averegeT, averegeH; // STORE THE AVEREGE OF DATA

///////////////////////////////////////////////////////////

///////////////////////DHT/////////////////////////////////

#include "DHT.h"

#define DHTPIN 2 // the digital pin of sensor

#define DHTTYPE DHT11 // define the type of sensor


DHT dht(DHTPIN,DHTTYPE); // initialize DHT sensor

// THE ARAY FOR STORING AND CALCULATING THE AVEREGE
  float TempSample[4]= {0,0,0,0};
  float HumSample[4]= {0,0,0,0};
  
  int counter=1; // COUNT THE SAMPLES

  
////////////////////////////////////////////////////////////

/////////////////////////////LCD////////////////////////////
 #include <LiquidCrystal.h>

 LiquidCrystal lcd(9, 8, 7, 6, 5, 4);
/////////////////////////////////////////////////////////////////

void setup() {
  Serial.begin(9600); // SERIAL INITIALIZE

  dht.begin();  // DHT INITIALIZE

  // GIVE THE FIRST VALUES UNTIL THE FIRST AVEREGE CHECK
    averegeT=dht.readTemperature();
    averegeH=dht.readHumidity();
  

  lcd.begin(16,2);  // LCD 16x2 INITIALIZE
  

  setTime(00,00,00,19,2,19); // SET THE TIME AS ZERO TO COUNT THE TIME IT RUNS


  Serial.print("Initializing SD card...");

  // see if the card is present and can be initialized:
  if (!SD.begin(chipSelect)) {
    Serial.println("Card failed, or not present");
    lcd.print("Card Failed");
    // don't do anything more:
    while (1);
  }
  Serial.println("card initialized.");
  lcd.clear();
  lcd.home();
  lcd.print("card initialized.");
  delay(1000);
  lcd.clear();
  
}

void loop() {
  

  samples();


  loging();

 
  lcd_print();


 

}//loop closing
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

void lcd_print()
{
/*
 * a FUCTION TO PRINT EVERY 30 SECONDS THE HUMIDITY 
 * AND TEMPRATURE AND PRINT THE TIME IS RUNNING FOR 
 * 27 SECOND EVERY TIME.
 */
    if (second()==1 || second()==30 )
  {
    lcd.setCursor(03,00);
  lcd.print(averegeH);
  lcd.print(" ");
  lcd.print(averegeT);
  lcd.print("   ");
  }

  lcd.home();
  lcd.setCursor(00,00);
  lcd.print(second());
  if (second()<=9)
  {
    lcd.setCursor(01,00);
    lcd.print("  ");
  }

  while (second()>0 && second()<29)
  {
    
    lcd.setCursor(00,01);
    lcd.print("Time : ");
    lcd.print(hour());
    lcd.print(":");
    lcd.print(minute());
    lcd.print(":");
    lcd.print(second());
    lcd.print("    ");
    break;
  }
  while (second()<59 && second()>29)
  {
    
    lcd.setCursor(00,01);
    lcd.print("Loged Hours ");
    lcd.print(lastWrite);
    lcd.print("   ");
  
  }
 
 
}




void samples()
{
/*
 * THE FUCTION THAT CALCULATES AND PRINTS BY SERIAL 
 * THE VARIABLE OF THE ARAYS AND THE AVEREGE 
 * EVERY 15 MINUTES
 * 
 */
  unsigned long curentmills=millis();
  if  (curentmills-lastSample>=900000)
  {
    lastSample=curentmills;
    float t=dht.readTemperature();
    float h = dht.readHumidity(); 

    switch (counter)
    {
      case 1:
      {
        
        TempSample[0]=t;
        HumSample[0]=h;
        break;
      }
      case 2:
      {
        
        TempSample[1]=t;
        HumSample[1]=h;
        break;
      }
      case 3:
      {
        
        TempSample[2]=t;
        HumSample[2]=h;
        break;
      }
      case 4:
      {
        
        TempSample[3]=t;
        HumSample[3]=h;
        break;
      }
    }
    
    Serial.println("===================================");
    
    for (int i=0; i<4; i++)
    {
    Serial.print("TempSample[");
    Serial.print(i);
    Serial.print("] = ");
    Serial.println(TempSample[i]);

    
    }
    
    Serial.println("===================================");

    for (int j=0; j<4; j++)
    {
      
    Serial.print("HumSample[");
    Serial.print(j);
    Serial.print("] = ");
    Serial.println(HumSample[j]);
    
    }
    
    Serial.println("===================================");


     float HumSampleMo= ( HumSample[0] +  HumSample[1] + HumSample[2] + HumSample[3]) /counter;
    Serial.print("HumSampleMo = ");
    Serial.println(HumSampleMo);
    
     float TempSampleMo= ( TempSample[0] +  TempSample[1] + TempSample[2] + TempSample[3]) /counter;
    Serial.print("TempSampleMo = ");
    Serial.println(TempSampleMo);
    
    Serial.println("===================================");
    
    averegeT = TempSampleMo;
    
    averegeH = HumSampleMo;
    
      

    counter++;
    if (counter>4)
    {
      counter=1;
      for (int i=0; i<4; i++)
      {

        
      TempSample[i] = 0;
      
      HumSample[i] = 0;
        
      }
    
    }
  }




  
}






void loging() 
{
  /*
   * THE FUCTION THAT STORING TO THE SD CARD THE 
   * AVEREGE OF HUMIDITY AND TEMPERATURE EVERY 1 HOUR
   * STARTS FROM 00:59:00
   */
 float h = dht.readHumidity(); // save humidity to memory

 float t = dht.readTemperature(); // save temperature in C to memory
 
 unsigned long curentnow=millis();

  
  if ( isnan(h) || isnan(t))
  {
    Serial.println("Failed to read from DHT sensor");
    lcd.clear();
    lcd.print("DHT MISING");
    
  }

 // if (second()==1)
  //if (minute()==59 && second()==0)
   if(curentnow-lastnow>=3600000)
  {
  lastnow=curentnow;


  dataString = " ";
  time = " ";
  
dataString += "Temperature Averege = ";
dataString += String(averegeT);
dataString += "\t";
dataString += "Humidity Averege = ";
dataString += String(averegeH);
dataString += "\n";
dataString += "Hours logged : ";
dataString += String(lastWrite);

time +="Time = ";
time +=String(hour());
time +=":";
time +=String(minute());
time +=":";
time +=String(second());
  // open the file. note that only one file can be open at a time,
  // so you have to close this one before opening another.
  File dataFile = SD.open("templog.txt", FILE_WRITE);

  // if the file is available, write to it:
  if (dataFile) {
    dataFile.println(time);
    dataFile.println(dataString);
    dataFile.flush();
    dataFile.close();
    // print to the serial port too:
    Serial.println(time);
    Serial.println(dataString);
  }
  // if the file isn't open, pop up an error:
  else {
    Serial.println("error opening datalog.txt");
  }
  lastWrite++;
  Serial.println(lastWrite);
  }


}

///////////////////////////////////////////////////////////////////////////////////////////////////////////