#include "DHT.h"
#include "Adafruit_Sensor.h"
#include "DHT_U.h"
#define no_dust 0.6
#define DHTPIN 10
#define FANPIN 3
#include <Arduino.h>
#include <Wire.h>
#include <SoftwareSerial.h>
float _ED_8C_AC = 0;
#include <LiquidCrystal.h>
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
float vo_value=0;
float sensor_voltage=0;
float dust_density=0;
float get_voltage(float value)
{
 float V= value * 5.0 / 1024; // 아날로그값을 전압값으로 바꿈
 return V;
}
float get_dust_density(float voltage)
{
 float dust=(voltage-no_dust) / 0.005; // 데이터 시트에 있는 미세먼지 농도(ug) 공식 기준
 return dust;
}
DHT dht(10,DHT22);
int v_led= A5;
int dustout= A4;
int s_ledr= 13;
int s_ledg= 12;
int s_ledb= 11;
int FAN= 3;
void _delay(float seconds)
{
  long endTime = millis() + seconds * 1000;
  while(millis() < endTime) _loop();
}
void setup() {
Serial.begin(9600);
Serial.println();
  lcd.begin(16, 2);
  lcd.setCursor(0,0);
  lcd.clear();
  dht.begin();
   pinMode(v_led,OUTPUT);
   digitalWrite(v_led,LOW);
  pinMode(s_ledr,OUTPUT);
  pinMode(s_ledg,OUTPUT);
  pinMode(s_ledb,OUTPUT);
  pinMode(FAN,OUTPUT);
  digitalWrite(s_ledr,LOW);
  digitalWrite(s_ledb,LOW);
  digitalWrite(s_ledg,LOW);
  digitalWrite(FAN,LOW);
  while(1) {
      float h= dht.readHumidity();
      float t = dht.readTemperature();
      float f = dht.readTemperature(true);
      float hif = dht.computeHeatIndex(f, h);
      float hic = dht.computeHeatIndex(t, h, false);
      int h1 = h;
      int hic1 = hic;
      lcd.setCursor(0,0);
      lcd.print("Temp:");
      lcd.setCursor(5,0);
      lcd.print(hic1);
      lcd.setCursor(7,0);
      lcd.print("C");
      lcd.setCursor(9,0);
      lcd.print("Hum:");
      lcd.setCursor(13,0);
      lcd.print(h1);
      lcd.setCursor(15,0);
      lcd.print("%");
      lcd.setCursor(0,1);
      lcd.print("Dust:");
      digitalWrite(v_led,LOW);
      delayMicroseconds(280); // 280us동안 딜레이
      vo_value=analogRead(dustout); // 데이터를 읽음
      delayMicroseconds(40); // 320us - 280us
      digitalWrite(v_led,HIGH); // 적외선 LED OFF
      delayMicroseconds(9680); // 10us(주기) -320us(펄스폭) 한 값
      sensor_voltage=get_voltage(vo_value); // get_voltage 함수 실행
      dust_density=get_dust_density(sensor_voltage); // get_dust_density 함수 실행
      int dust_density1 = dust_density;
      lcd.setCursor(5,1);
      lcd.print(dust_density1);
      lcd.setCursor(8,1);
      lcd.print("[ug/m^3]");
         if(dust_density <= 30){
          digitalWrite(s_ledr,LOW); digitalWrite(s_ledb,HIGH); digitalWrite(s_ledg,LOW);
         }
         else if(dust_density >= 200){
          digitalWrite(s_ledr,HIGH); digitalWrite(s_ledb,LOW); digitalWrite(s_ledg,LOW); digitalWrite(FAN,HIGH);
         }
         else {
          digitalWrite(s_ledr,LOW); digitalWrite(s_ledb,LOW); digitalWrite(s_ledg,HIGH);
         }
         if(h >=50){
          digitalWrite(FAN,HIGH);
          }
          else{
            digitalWrite(FAN,LOW);
         }
         if(t >=20){
          digitalWrite(FAN,HIGH);
         }
         else{
          digitalWrite(FAN,LOW);
         }
         }
         _delay(1);
         lcd.clear();
         _loop();
  }
void _loop(){
}
void loop(){
  _loop();
}
 
이렇게 코딩을 했는데 연결해서 lcd에 온습도값은 잘 나오고 팬 제어가 가능한데 lcd에 미세먼지값만 너무빨리 띄어서 아무리 수정해봐도 문제점을 잘 모르겠어요ㅠㅜ 
어디부분이 문제일까요..?