// LCD1602 to Arduino Uno connection example

#include <LiquidCrystal.h>
#include "DHT.h"
#include <Servo.h>
Servo servo1;
const int servoPin1 = 3;
int val = 0;
#define DHTPIN 2
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

LiquidCrystal lcd(12, 11, 10, 9, 8, 7);

const int numRows = 4; 
const int numCols = 4; 
const int debounceTime = 20; 
const char keymap[numRows][numCols] = {
    { '1', '2', '3','A' } ,
    { '4', '5', '6','B' } ,
    { '7', '8', '9','C' } ,
    { '*', '0', '#','D' }
};
const int rowPins[numRows] = { 7, 2, 3, 6 }; 
const int colPins[numCols] = { 5, 8, 4, 9 }; 

void setup() {
  lcd.begin(16, 2);
  // you can now interact with the LCD, e.g.:
  lcd.print("Enter the password!");

   Serial.begin(9600);
    for (int row = 0; row < numRows; row++) {
        pinMode(rowPins[row], INPUT);
        digitalWrite(rowPins[row], HIGH);
    }
    for (int column = 0; column < numCols; column++) {
        pinMode(colPins[column], OUTPUT);
        digitalWrite(colPins[column], HIGH);
    }
     Serial.begin(9600);
  Serial.println(F("DHTxx test!"));

  dht.begin();
}
void loop() {
  // ...
  char key = getKey();
    if (key != 0) {
        Serial.print("Got key ");
        Serial.println(key);
    }
}

char getKey() {
    char key = 0;
    for (int column = 0; column < numCols; column++) {
        digitalWrite(colPins[column], LOW);
        for (int row = 0; row < numRows; row++) {
            if (digitalRead(rowPins[row]) == LOW) {
                delay(debounceTime);
                while (digitalRead(rowPins[row]) == LOW)
                    ;
                key = keymap[row][column];
            }
        }
        digitalWrite(colPins[column], HIGH);
    }
    return key;
     delay(2000);
  float h = dht.readHumidity();
  
  float t = dht.readTemperature();
  
  float f = dht.readTemperature(true);

  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println(F("Failed to read from DHT sensor!"));
    return;
  }
  float hif = dht.computeHeatIndex(f, h);
  float hic = dht.computeHeatIndex(t, h, false);

  Serial.print(F("Humidity: "));
  Serial.print(h);
  Serial.print(F("%  Temperature: "));
  Serial.print(t);
  Serial.print(F("°C "));
  Serial.print(f);
  Serial.print(F("°F  Heat index: "));
  Serial.print(hic);
  Serial.print(F("°C "));
  Serial.print(hif);
  Serial.println(F("°F"));
}