Thermostat

Intro: Thermostat

This device takes the current room temperature, and displays the room temperature. The potentiometer on the bottom allows you to select a temperature, the LED shows if the temperature is over the desired, and the button allows you to switch between Celsius and Fahrenheit.
You will need

- two potentiometers
- an lcd screen
- a LED
- a button
- an arduino uno
- a breadboard
- a lot of wires

STEP 1: Assembly

Use the attached image for assembly

STEP 2: Program

int cel;
int far;
char let;
boolean cf;
int desC;
int desF;
int inputDes;
int temp;
int changeTime = 2;
float voltage;
#include

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {
lcd.begin(16, 2);
pinMode(8, INPUT);
pinMode(9, OUTPUT);


}

void loop() {
voltage = getVoltage(0);
desC = (getVoltage(5) / 10) * 100;
desF = Far(desC) + 20;
inputDes = (analogRead(5) / 20.5);
cel = (voltage - 0.5) * 100;
far = Far(cel);


lcd.setCursor(0, 0); //LCD code
lcd.print("Temperature:");
lcd.setCursor(13, 0);
lcd.print(temp);
lcd.setCursor(15, 0);
lcd.print(let); //Display

lcd.setCursor(0, 1);
lcd.print("Desired:");
lcd.setCursor(9,1);
if (cf == true) {
lcd.print(desF);
lcd.setCursor(11,1);
} else {
lcd.print(desC);
lcd.setCursor(11,1);
if (desC < 10) {
lcd.print(" ");
lcd.setCursor(10,1);
}
}
lcd.print(let's);


if (cf == true) { //Temp Toggle
let = 'F';
temp = far;

} else if (cf == false) {
let = 'C';
temp = cel;
}
if (cel > desC) {
digitalWrite(8, HIGH);
} else {
digitalWrite(8, 0);
}

changeTime--;
if (analogRead(4) > 1000 && changeTime < 0) { //temp toggle input
cf = !cf;
changeTime = 2;
}
delay(150);
}

float Far (float a) { //farenheit conversion
float b = (a * (9 / 5)) + 32;
return b;
}

float getVoltage (float a) {
float b = (analogRead(a) * 0.004882814);
return b;
}

STEP 3: Modification

Of course, as this is a very simple project, one could substitute some sort of motor to be controlled in place of the led. There are countless ways this could be altered for the better.

Comments

[D6equj5]

Where is the temperature sensor?

[monocogger]

That's what I was wondering too