Codes

prototype number 1

From the way we connected our circuit, the power supply is giving 5 volts, with 2k ohms. The output in this case which is the temperature reading is connected to analog A0. The ATmega328 will read the resulting voltage as an (ADC) input.

[ADC stands for Analog to Digital Converter]

Therefore we have to use a formula. Since we know the total Voltage,(Vt), (ADC total) = 1024, and (ADC calculated) which is the reading provided in analog A0. We can find the numerical calculated voltage reading.

As the temperature sensor has a breakdown voltage directly proportional to absolute temperature at +10mV/K, with the voltage reading, we can find out the temperature in Kelvin. 

Converting from Kelvin to Celsius, we need to minus 273.15

Hence the code we uploaded into the Arduino software to calculate this reading is as shown below;

float tempK=0, tempC=0, tempF=0;

void setup(){

  Serial.begin(9600);                               //Setup serial to 9600 bps

}

void loop(){

  float reading = analogRead(A0) * 5.0;   //Where 5V and the Analog (ADC) input

  reading /= 1024.0;                                // is used to determine the voltage reading

  

  tempK = reading * 100;                       //Read temperature in Kelvins first

  tempC = tempK - 273.15;                   //Convert from Kelvin to Celsius

  tempF = ((tempK) * 9 / 5) - 459.67;    //Convert from Kelvin to Fahrenheit

  //Print all the values to Serial

  Serial.print("Voltage: ");                       //Print the reading of the voltage

  Serial.println(reading);                         //on Serial Monitor

  

  Serial.println();

  Serial.print("Kelvin: ");                        //Print the reading of the temperature

  Serial.println(tempK);                         //in Kelvin on Serial Monitor

  Serial.print("Celsius: ");                       //Print the reading of the temperature

  Serial.println(tempC);                         //in Celsius on Serial Monitor

  Serial.print("Fahrenheit: ");                 //Print the reading of the temperature

  Serial.println(tempF);                         //in Fahrenheit on Serial Monitor

  Serial.println();                                   //Print Blank Line

  delay(3000);                                      //Delay 1.5 second

}