box_dht22.ino

#include "DHT.h"
#include <Wire.h> 
#include <LiquidCrystal_I2C.h> 

#define DHTPIN 14
#define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2);

/* ICON */
byte ICON_TEMP[8]       {B00100,B01010,B01010,B01110,B01110,B11111,B11111,B01110};
byte ICON_HUMID[8]      {B00100,B00100,B01010,B01010,B10001,B10001,B10001,B01110};

unsigned long previousMillis = 0;
const long interval = 2000;

void ledDisplay(float temp, float humid) {
  lcd.clear();
  lcd.setCursor(0, 1);
  lcd.print("     ");
  lcd.write(1);
  lcd.print(" : ");
  lcd.print(temp);
  lcd.print(" C");
  lcd.setCursor(0, 2);
  lcd.print("     ");
  lcd.write(2);
  lcd.print(" : ");

  if (humid <= 9) {
     lcd.print("0");
  }
  
  lcd.print(humid);
  lcd.print(" %");
}

void setup() {
  Serial.begin(115200);
  dht.begin();
  lcd.begin();
  lcd.createChar(1, ICON_TEMP);
  lcd.createChar(2, ICON_HUMID);
}

void loop() {
  
  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {
    
    previousMillis = currentMillis;
    float h = dht.readHumidity();
    float t = dht.readTemperature();
  
    if (isnan(h) || isnan(t)) {
      Serial.println("Failed to read from DHT sensor!");
      return;
    }

    Serial.print("Temp : ");
    Serial.println(t);
    Serial.print("Humid : ");
    Serial.println(h);
  
    ledDisplay(t, h);
    
  }
  
  
}