/* this is an extension of several sketches I found online, some parts from
arduino.cc playground, and some from a northeastern university project.
Yes, I'm lacking a lot of comments within the code, maybe I'll flesh it out
later, as I add a few other things to it.
runs quite nicely on a pro mini.

Things to add:

 RTC for pump timer relay
 control to shut down the pump when the heater return cools below a set temperature

 There are a couple more things I'll add later*/


#include <math.h>
#include <LiquidCrystal.h>

LiquidCrystal lcd (2,3,4,5,6,7); /* 2=rs; 3=enable; 4=D4; 5=D5; 6=D6; 7=D7 */

 double Thermistor1(int RawADC) {
 double TempA;
 TempA = log(10000.0*(1024.0/RawADC-1));
//         =log(10000.0/(1024.0/RawADC-1)) // for pull-up configuration
 TempA = 1 / (0.001129148 + (0.000234125 + (0.0000000876741 * TempA * TempA ))* TempA );
 TempA = TempA - 273.15;            // Convert Kelvin to Celcius
 TempA = (TempA * 9.0)/ 5.0 + 32.0; // Convert Celcius to Fahrenheit
 return TempA;
}

double Thermistor2(int RawADC) {
 double TempB;
 TempB = log(10000.0*(1024.0/RawADC-1));
//         =log(10000.0/(1024.0/RawADC-1)) // for pull-up configuration
 TempB = 1 / (0.001129148 + (0.000234125 + (0.0000000876741 * TempB * TempB ))* TempB );
 TempB = TempB - 273.15;            // Convert Kelvin to Celcius
 TempB = (TempB * 9.0)/ 5.0 + 32.0; // Convert Celcius to Fahrenheit
 return TempB;
}

double Thermistor3(int RawADC) {
 double TempC;
 TempC = log(10000.0*(1024.0/RawADC-1));
//         =log(10000.0/(1024.0/RawADC-1)) // for pull-up configuration
 TempC = 1 / (0.001129148 + (0.000234125 + (0.0000000876741 * TempC * TempC ))* TempC );
 TempC = TempC - 273.15;            // Convert Kelvin to Celcius
 TempC = (TempC * 9.0)/ 5.0 + 32.0; // Convert Celcius to Fahrenheit
 return TempC;
}

double Thermistor4(int RawADC) {
 double TempD;
 TempD = log(10000.0*(1024.0/RawADC-1));
//         =log(10000.0/(1024.0/RawADC-1)) // for pull-up configuration
 TempD = 1 / (0.001129148 + (0.000234125 + (0.0000000876741 * TempD * TempD ))* TempD );
 TempD = TempD - 273.15;            // Convert Kelvin to Celcius
 TempD = (TempD * 9.0)/ 5.0 + 32.0; // Convert Celcius to Fahrenheit
 return TempD;
}

void setup() {
 //Serial.begin(115200);
 lcd.begin(20,4);
}

void loop() {

 lcd.setCursor(0,0);
 lcd.print("Pool Return:");
 lcd.setCursor(14,0);
 lcd.print(int(Thermistor1(analogRead(0))));
 lcd.print(" ");
 lcd.print((char)223);
 lcd.print("F ");

 lcd.setCursor(0,1);
 lcd.print("Heater in:");
 lcd.setCursor(14,1);
 lcd.print(int(Thermistor2(analogRead(1))));
 lcd.print(" ");
 lcd.print((char)223);
 lcd.print("F ");

 lcd.setCursor(0,2);
 lcd.print("Heater out:");
 lcd.setCursor(14,2);
 lcd.print(int(Thermistor3(analogRead(2))));
 lcd.print(" ");
 lcd.print((char)223);
 lcd.print("F ");

 lcd.setCursor(0,3);
 lcd.print("Air:");
 lcd.setCursor(14,3);
 lcd.print(int(Thermistor4(analogRead(3))));
 lcd.print(" ");
 lcd.print((char)223);
 lcd.print("F ");

 delay(1000);

 lcd.clear();
}