#include <Wire.h>
#define LCD_ADRS 0x3E
#define TEMP_SENSOR 3  // Analog port 3

int ans, tv, temp;
char moji[]="Temperature.....";
char s[]="                ";

//SCL = A5:LCD No.2  SDA=A4:LCD No.3

void setup() {
  Wire.begin();
  init_LCD();
  Serial.begin(9600);
}

void loop() {
  ans = analogRead(TEMP_SENSOR);
  tv = map(ans, 0, 1023, 0, 5000);
  temp = map(tv, 300, 1600, -30, 100);
  Serial.println(temp);
  sprintf(s, "temp = %2d", temp);
  s[9]=0xDF;
  s[10]='C';
  
  writeCommand(0x01);   //Clear Display
  writeCommand(0x80);   //1st Line top
  for(int i=0; i<16; i++) {
    writeData(moji[i]);
  }
  writeCommand(0x40+0x80);   //2nd Line top
  for(int i=0; i<16; i++) {
    writeData(s[i]);
  }
  delay(1000);
}

void writeData(byte t_data) {
  Wire.beginTransmission(LCD_ADRS);
  Wire.write(0x40);
  Wire.write(t_data);
  Wire.endTransmission();
  delay(1);
}

void writeCommand(byte t_command){
  Wire.beginTransmission(LCD_ADRS);
  Wire.write(0x00);
  Wire.write(t_command);
  Wire.endTransmission();
  delay(10);
}

void init_LCD() {
  delay(100);
  writeCommand(0x38);
  delay(20);
  writeCommand(0x39);
  delay(20);
  writeCommand(0x14);
  delay(20);
  writeCommand(0x73);
  delay(20);
  writeCommand(0x56);  // 3.3V
  //writeCommand(0x52);  // 5V
  delay(20);
  writeCommand(0x6C);
  delay(20);
  writeCommand(0x38);
  delay(20);
  writeCommand(0x01);
  delay(20);
  writeCommand(0x0C);
  delay(20);
}