Thermal Sensor LM35DZ/Arduino UNO R3

LM35DZ.ino

#include <LiquidCrystal.h>

// http://arduino.cc/en/Reference/AnalogReference

unsigned int t,c;
float sc;
int sensor0 = A0 ;
int value = 0 ;

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

float temp5v(int ain) {  // analog 0-1023 10mV/Celsius ,5V*100/1024
  return ain*500/1024;
}

float temp3v3(int ain) {  // analog 0-1023 10mV/Celsius,3.3V*100/1024
  return ain*330/1024;
}

float temp2v56(int ain) {  // analog 0-1023 10mV/Celsius,2.56V*100/1024
  return ain*256/1024;
}


void setup() {
  // set up the LCD's number of columns and rows: 
  lcd.begin(16, 2);
  // External Aref(3.3V)
  analogReference(EXTERNAL);
  // Internal Aref(2.56V) ATmega328 ???
  //analogReference(INTERNAL);
}

void loop() {

  t=analogRead(sensor0); // (0...1023)
  sc=temp3v3(t);
  lcd.setCursor(0,0);lcd.print("        ");lcd.setCursor(0,0);
  lcd.print(t);
  lcd.setCursor(0,1);lcd.print("        ");lcd.setCursor(0,1);
  lcd.print(sc);
  delay(5000);
}