Author : Maheshkumar W
#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
float temp;
int tempPin = A1;
int relayPin = 8;
#define fan 9
void setup(){
pinMode(fan, OUTPUT);
pinMode(relayPin, OUTPUT);
lcd.begin(16, 3);
lcd.setCursor(1, 1);
lcd.print("Automated Temperature Control");
delay(1000);
lcd.clear();
lcd.setCursor(3,0);
lcd.print("Develped By YOUR NAME");
delay(1000);
lcd.clear();
lcd.print("Lets Get Started");
delay(2000);
lcd.clear();
lcd.print("AUTO TEMPERATURE");
delay(2000);
lcd.clear();
}
void loop()
{
lcd.setCursor(3,0);
lcd.print("Recording");
lcd.setCursor(2, 1);
lcd.print("Temperature..");
delay(3000);
lcd.clear();
lcd.setCursor(0,2);
temp = analogRead(tempPin);
//temp = temp*0.48828125;
float voltage = temp * 5.0;
voltage /= 1024.0;
// print out the voltage
lcd.print(voltage); lcd.println(" volts");
// now print out the temperature
float temperatureC = (voltage - 0.5) * 100 ; //converting from 10 mv per degree wit 500 mV offset
//to degrees ((voltage - 500mV) times 100)
lcd.setCursor(0, 0);
lcd.print("Temperature = ");
lcd.setCursor(2,1);
//lcd.print(temp);
lcd.print(temperatureC); lcd.println(" degrees C");
delay(3000);
lcd.clear();
if(temperatureC >= 20)
{
poweronRelay();
if(temperatureC >= 20 && temperatureC <= 25)
{
analogWrite(fan,51);
lcd.print("Fan Speed: 20% ");
delay(2000);
lcd.clear();
}
else if(temperatureC <= 35)
{
analogWrite(fan,102);
lcd.print("Fan Speed: 40% ");
delay(2000);
lcd.clear();
}
else if(temperatureC <= 40)
{
analogWrite(fan,153);
lcd.print("Fan Speed: 60% ");
delay(2000);
lcd.clear();
}
else if(temperatureC <= 44)
{
analogWrite(fan,200);
lcd.print("Fan Speed: 80% ");
delay(2000);
lcd.clear();
}
else if(temperatureC >= 45)
{
analogWrite(fan,255);
lcd.print("Fan Speed: 100% ");
delay(2000);
lcd.clear();
}
}
else if(temperatureC < 20)
{
poweroffRelay();
}
}
void poweronRelay()
{
digitalWrite(relayPin, HIGH);
lcd.print("Fan ON");
delay(2000);
lcd.clear();
}
void poweroffRelay()
{
digitalWrite(relayPin, LOW);
analogWrite(fan,0);
lcd.print("Fan OFF");
delay(2000);
lcd.clear();
}