Arduino climiate monitor and control system that uses an Sensirion temperature and humidity sensor, a Maxim (Dallas) RTC and a Samsung 20x2 VFD display. RTC time is in 12 hour mode.

ClimateControlrev0b.pde

/* Arduino Climate Monitor and Control system By JS106351

Remember! You have to upload the sketch twice, once to set the time, and the second time
to remove the setClock() function as to not accidentally reset the clock at power up. 

Compatible RTC's include the DS1307 and the DS3231 (from what I know)

The code is set to control the humidity level in the room, but can be changed to control temperature too.  

*/

#include <Sensirion.h>
const uint8_t dataPin  =  3;
const uint8_t clockPin =  4;
float temperature;
float humidity;
float dewpoint;
Sensirion tempSensor = Sensirion(dataPin, clockPin);



#define SETCLOCK     //compile clock setup code
int n;
#include <Wire.h>
#include <SPI_VFD.h>
SPI_VFD vfd(10, 11, 12, VFD_BRIGHTNESS25);
uint8_t brightness = 0;



#define DS1307_I2C_ADDRESS 0x68       //seven bit address
#define AM 0
#define PM 1
#define Mode12 1



void setup(){
  Wire.begin();
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  vfd.setBrightness(3);
  //setClock();  // uncomment this to set the time, upload code, 
                 //then recomment and upload the code again to avoid resetting time 
}



void loop()
{
  byte second, minute, hour, dayOfWeek, dayOfMonth, month, year, ampm;

  getClock(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year, &ampm);
  
int hours= hour;
int minutes=minute;
int seconds=second;

  if (hours<10){
    vfd.setCursor(9,1);
    vfd.print("0");
    vfd.setCursor(10,1);
    vfd.print(hour, DEC);
  }else{
    vfd.setCursor(9,1);
    vfd.print(hour, DEC); 
  }
  
  vfd.setCursor(11,1);
  vfd.print(":");
  
  if (minutes<10){
    vfd.setCursor(12,1);
    vfd.print("0");
    vfd.setCursor(13,1);
    vfd.print(minute, DEC);
  }else{
    vfd.setCursor(12,1);
    vfd.print(minute, DEC);
  }
  
  vfd.setCursor(14,1);
  vfd.print(":");
  
  if (seconds<10){
    vfd.setCursor(15,1);
    vfd.print("0");
    vfd.setCursor(16,1);
    vfd.print(second, DEC);
  }else{
    vfd.setCursor(15,1);
    vfd.print(second, DEC);
  }
  
  
  if (ampm != ' ') {
    vfd.setCursor(18,1);    //not space
    //vfd.print(" ");
    vfd.print(ampm);
    vfd.setCursor(19,1);
    vfd.print("M");
  }  
  
  
  
  
  n++;
int setpoint=map(analogRead(0), 0, 1023, 40, 60);
if (n==5){
    tempSensor.measure(&temperature, &humidity, &dewpoint);

  vfd.setCursor(0,0);
  vfd.print("RH");
  vfd.setCursor(3,0);
  vfd.print(humidity,1);
  vfd.setCursor(7,0);
  vfd.print("%");
  
  
  vfd.setCursor(0,1);
  vfd.print("TH");
  vfd.setCursor(3,1);
  vfd.print(convertToFahrenheit(temperature),1);
  vfd.setCursor(7,1);
  vfd.print("%");
  digitalWrite(5, HIGH);
  n=0;
}else{
  digitalWrite(5, LOW);
}

if (humidity>setpoint+3){
  digitalWrite(6, LOW);
  vfd.setCursor(17,0);
  vfd.print("OFF");
}
else if (humidity<setpoint-3){
  digitalWrite(6, HIGH);
  vfd.setCursor(17,0);
  vfd.print(" ON");
}
vfd.setCursor(9,0);
vfd.print("SP");
vfd.setCursor(12,0);
vfd.print(setpoint);
vfd.setCursor(14,0);
vfd.print("%");

 delay(1000);
}



float convertToFahrenheit(float c) {
  return ((9.0 / 5.0) * c) + 32.0;
} 



 /*void leadzero(byte val) {
  if (val < 10) {
    vfd.print("0");
  }  
}*/   //Part of original code but was not needed and was commented out.  

void setClock() {
 //prompt for time settings
 byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
 byte mode = 0;
 byte ampm = 0;
 year = 12;                 //Set the year
 month = 12;                //Set the month 1-12
 dayOfMonth = 12;           //Set the day  1-31
 dayOfWeek = 5;             //Set the day of week 1-7
 mode = Mode12;             //12 hour mode
 ampm = PM;                 //Set part of day AM or PM
 hour = decToBcd(2);        //Set the hour 1-12
 minute = 28;               //Set the minute 0-59
 second = 8;                //Set the seconds 0-59
 if (mode == Mode12) {
   bitSet(hour,  6);
   if (ampm == PM) {
      bitSet(hour, 5);
   }  
 }  
 Wire.beginTransmission(DS1307_I2C_ADDRESS);
 Wire.send(0);
 Wire.send(decToBcd(second));    // 0 to bit 7 starts the clock
 Wire.send(decToBcd(minute));
 Wire.send(hour);                                      //already formatted with bits 6 and 5
 Wire.send(decToBcd(dayOfWeek));
 Wire.send(decToBcd(dayOfMonth));
 Wire.send(decToBcd(month));
 Wire.send(decToBcd(year));
 Wire.endTransmission();
}






void getClock(byte *second,
          byte *minute,
          byte *hour,
          byte *dayOfWeek,
          byte *dayOfMonth,
          byte *month,
          byte *year,
          byte *ampm)
{
  byte work;
  byte mode;          //12 or 24 hour
  byte ap_ind;       //am or pm indicator
  
  // Reset the register pointer
  Wire.beginTransmission(DS1307_I2C_ADDRESS);
  Wire.send(0);
  Wire.endTransmission();

  Wire.requestFrom(DS1307_I2C_ADDRESS, 7);

  // A few of these need masks because certain bits are control bits
  *second     = bcdToDec(Wire.receive() & 0x7f);      //mask CH bit (bit 7)
  *minute     = bcdToDec(Wire.receive());

//  *hour = bcdToDec(Wire.receive());
  work = Wire.receive();                                                // get hour byte
  mode =  bitRead(work, 6);                                         // if bit  6  set,  running 12 hour mode
  if (mode == Mode12) {
    ap_ind = bitRead(work, 5);                                      // if bit 5 set,  time is PM
    *hour = bcdToDec(work & 0x1f);                             // mask bits 5 thru 7 for 12 hour clock
    if (ap_ind == PM) {
      *ampm = 'P';
    }else{
      *ampm = 'A';
    }  
  }else{  
    *hour = bcdToDec(work & 0x3f);                             // mask bits 6 and 7 for 24 hour clock
    *ampm = ' ';  
  }  

  *dayOfWeek  = bcdToDec(Wire.receive());
  *dayOfMonth = bcdToDec(Wire.receive());
  *month      = bcdToDec(Wire.receive());
  *year       = bcdToDec(Wire.receive());
}




byte decToBcd(byte val)
{
  return ( (val/10*16) + (val%10) );
}

// Convert binary coded decimal to normal decimal numbers
byte bcdToDec(byte val)
{
  return ( (val/16*10) + (val%16) );
}