// MCU BASIC: https://www.basic4mcu.com
// DateTime : 2018-06-18 오전 11:13:04
// by Ok-Hyun Park
//
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F,16,2); // 접근주소: 0x3F or 0x27
//
#include "DHT.h"
#define DHTPIN   10    // DHT11이 연결된 핀
#define DHTTYPE  DHT11 // DHT 11,DHT시리즈중 11을 선택합니다.
DHT dht(DHTPIN,DHTTYPE);
//
int dust_sensor=A0;    // 미세먼지 핀 번호
int rgb_R=5;           // rgb 핀 빨간색 핀
int rgb_G=6;           // rgb핀 녹색 핀
int rgb_B=7;           // rgb핀 파란색 핀
int piezo=3;
//
float dust_value=0;    // 센서에서 입력 받은 미세먼지 값
float dustDensityug=0; // ug/m^3 값을 계산
int sensor_led=12;     // 미세먼지 센서 안에 있는 적외선 led 핀 번호
int sampling=280;      // 적외선 led를 키고,센서 값을 읽어 들여 미세먼지를 측정하는 샘플링 시간
int waiting=40;
float stop_time=9680;  // 센서를 구동하지 않는 시간
//
void setup(){
  Serial.begin(9600);
  pinMode(sensor_led,OUTPUT);                                          // 미세먼지 적외선 led
  pinMode(rgb_R,OUTPUT); pinMode(rgb_G,OUTPUT); pinMode(rgb_B,OUTPUT); // 3색 LED
  pinMode(piezo,OUTPUT);
  lcd.init(); lcd.backlight();
  dht.begin();
}
//
void loop(){
  float h=dht.readHumidity();    // 습도 측정
  float t=dht.readTemperature(); // 온도 측정
  //
  if(isnan(h)||isnan(t)){        // 오류 출력
    Serial.println("Failed to read from DHT sensor!");
    return;
  }
  float hic=dht.computeHeatIndex(t,h,false); // 보정된 섭씨
  //
  digitalWrite(sensor_led,LOW);       delayMicroseconds(sampling ); // LED 켜기
  dust_value=analogRead(dust_sensor); delayMicroseconds(waiting  ); // 센서 값 읽어오기
  digitalWrite(sensor_led,HIGH);      delayMicroseconds(stop_time); // LED 끄기
  dustDensityug=(0.17*(dust_value*(5.0/1024))-0.1)*1000;            // 미세먼지 값 계산
  //
  lcd.setCursor(0,0); lcd.print(h,0); lcd.print("% "); lcd.print(hic,0); lcd.print("*C "); // 1라인
  //
  lcd.setCursor(0,1);  lcd.print(dustDensityug); // 2라인
  //
  if(dustDensityug<=30.0){ // 대기 중 미세먼지가 좋음 일 때 파란색 출력
    analogWrite(rgb_R,0); analogWrite(rgb_G,0); analogWrite(rgb_B,255); lcd.print("blue");
  } else if(30.0<dustDensityug&&dustDensityug<=80.0){ // 보통 녹색 
    analogWrite(rgb_R,0); analogWrite(rgb_G,255); analogWrite(rgb_B,0); lcd.print("green");
  } else if(80.0<dustDensityug&&dustDensityug<=150.0){ // 나쁨 노란색 
    analogWrite(rgb_R,255); analogWrite(rgb_G,155); analogWrite(rgb_B,0); lcd.print("yellow");
    digitalWrite(piezo,HIGH); delay(1000); digitalWrite(piezo,LOW); delay(1000);
  } else{ // 매우 나쁨 빨간색
    analogWrite(rgb_R,255); analogWrite(rgb_G,0); analogWrite(rgb_B,0); lcd.print("red");
    digitalWrite(piezo,HIGH); delay(1000); digitalWrite(piezo,LOW); delay(1000);
  }
  delay(2000);
}