#include <DHT.h>
#include <LiquidCrystal_I2C.h>
#include <ArduinoJson.h>
const int dhtPin = 14;
const int triggerPin = 12;
const int echoPin = 27;
DHT dht(dhtPin, DHT22);
LiquidCrystal_I2C lcd(0x27, 20, 4);
DynamicJsonDocument doc(1024);
int curMillis=0;
int prevMillis=0;

void setup() {
  
  Serial.begin(115200);
  lcd.init();
  lcd.backlight();
  lcd.begin(20, 4);
dht.begin();
}
void loop() {

//delay(1000);// Delay for readability
curMillis=millis();
while(curMillis-prevMillis>1000)
  {
    prevMillis=curMillis;
    // Wait a few seconds between measurements.
//delay(2000);
// Reading temperature or humidity takes about 250 milliseconds!
// Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
float humidity=dht.readHumidity();
// Read temperature as Celsius (the default)
float temperature = dht.readTemperature();
lcd.setCursor(0,0);
lcd.print("Humiditiy : "+String(humidity));
lcd.setCursor(0,1);
lcd.print("Temp  : "+String(temperature));
Serial.println("Humiditiy : "+String(humidity));
Serial.println("TEmp is : "+String(temperature));

lcd.setCursor(0,2);
digitalWrite(triggerPin, LOW);
delayMicroseconds(2);
digitalWrite(triggerPin, HIGH);
delayMicroseconds(10);
digitalWrite(triggerPin, LOW);
// Measure the echo time
float duration = pulseIn(echoPin, HIGH);
// Calculate the distance in centimeters
// distance=duration×0.034cm/μs/2
// 0.034 speed of sound in air
float distance = duration * 0.034 / 2;
lcd.print("Duration: " + String(duration)); //(char)223 = degree symbol
lcd.setCursor(0,3);
lcd.print("Distance: " + String(distance,0) + " cm");
String JsonData;
doc["Temperature"]=temperature;
doc["Humidity"]=humidity;
doc["Distance"]=distance;
serializeJson(doc,JsonData);
Serial.println(JsonData);
  }
}