// program to send data to processing.org
// jans hendry @2022

const int tp_pin = 5; // sensor pin
const int stay = 16; // led pin always on
const int red = 9; // red pin
const int yellow = 11; // yellow pin
const int green = 10; // green pin

#define vref 4000 // voltage ref according to vcc
#define adcres 1024.0 // adc resolution
#define mv 10 // 1oc  = 10 mv

void setup() {
  // start serial
  Serial.begin(9600);

  // set input pin
  pinMode(stay, OUTPUT);
  digitalWrite(stay, HIGH);
  pinMode(red, OUTPUT);
  pinMode(yellow, OUTPUT);
  pinMode(green, OUTPUT);
  digitalWrite(red, LOW);
  digitalWrite(yellow, LOW);
  digitalWrite(green, LOW);

  // delay
  delay(500);
}

void loop() {
  // read analogue data (lm32 temperature sensor);
  int sensdata = analogRead(tp_pin);
//  Serial.print("Sensor reading: ");
//  Serial.println(sensdata);

  // convert to celcius
  float vt = (sensdata / adcres) * vref; // voltage to be converted
  float suhu = (vt / mv); // celcius temperature
//  Serial.print("Voltage out: ");
//  Serial.println(vt);
//  Serial.print("Temperature (oC): ");
//  Serial.println(suhu);

  send_sign(suhu); // turn light indicator  
  Serial.write((int)suhu); // provide INT instead of FLOAT to write to serial.
  delay(1000); // take a break every 1 second
}

int send_sign(float tmp){
  // turn light
  if (tmp >= 35){
    digitalWrite(red, HIGH);
    digitalWrite(yellow, LOW);
    digitalWrite(green, LOW);
  }
  else if (tmp >= 30){
    digitalWrite(red, LOW);
    digitalWrite(yellow, HIGH);
    digitalWrite(green, LOW);
  }
  else {
    digitalWrite(red, LOW);
    digitalWrite(yellow, LOW);
    digitalWrite(green, HIGH);
  }
  return 0;
}