Published March 26, 2021 © GPL3+

DHT22 Sensor with 16x2 LCD Screen

Monitor Temperature & Humidity of a room on LCD Screen using Arduino Mega

BeginnerShowcase (no instructions)7,385

Things used in this project

Hardware components

Arduino Mega 2560

RGB LCD Shield Kit, 16x2 Character Display

DHT22 Temperature Sensor

Jumper wires (generic)

Breadboard (generic)

Software apps and online services

Arduino IDE

Story

In this project, we are trying to monitor the Temperature and Humidity of a closed area like a Meeting/Conference room, Cabins, cubicles. So we have connected the temperature measurement sensor to the LCD screen with the help of an Arduino device.

For this project, you need to download & install two libraries LiquidCrystal & DHT library. You can download those libraries from GitHub or directly from Arduino IDE

Github links -

LiquidCrystal - https://github.com/arduino-libraries/LiquidCrystal

DHT - https://github.com/adafruit/DHT-sensor-library

From Arduino IDE -

Go to Sketch > Include Library > Manage Libraries. The Library Manager should open. Search for "DHT" on the Search box and install the DHT library from Adafruit. Now after that search for "LiquidCrystal" on the search box and install the LiquidCrystal library build by Ardunio, Adafruit.

The LiquidCrystal library will be used for LCD Screen to print the output on LCD. To wire your LCD screen to your board, connect the following pins:

LCD RS pin to digital pin 12

LCD Enable(E) pin to digital pin 11

LCD D4 pin to digital pin 5

LCD D5 pin to digital pin 4

LCD D6 pin to digital pin 3

LCD D7 pin to digital pin 2

LCD R/W pin to GND

LCD VSS pin to GND

LCD VCC pin to 5V

LCD LED+ to 3.3V

LCD LED- to GND

DHT library will be used to get temperature and humidity from the DHT22 sensor. DHT Library gives temperature output in Celsius by default if you want to convert into Fahrenheit then change one line -

 float air_temp = dht.readTemperature(true);

Just add true (isFahrenheit = true) so it will display the output Fahrenheit.

This project is just for fun and learning. I look forward to suggestions or any comments.

Code

LED With DHT22 Temp. Sensor

/* LCD Screen */
#include <LiquidCrystal.h
const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

/* Temperature humidity sensor */
#include <DHT.h>
#define datapin 7     // Digital pin we're connected to
#define DHTTYPE DHT22
DHT dht(datapin, DHTTYPE);


void setup() {
  dht.begin(); 
  lcd.begin(16, 2);
}

void loop() {

  /* Find Temperature & Humidity */
  float air_temp = dht.readTemperature();
  float humidity = dht.readHumidity();
  
  /* Print Output on LCD Screen */
  lcd.setCursor(0,0);
  lcd.print(String("Temp. ") + String(air_temp));
  lcd.setCursor(0,1);
  lcd.print(String("Humidity ") + String(humidity));

  delay(2000);

}

Credits

abshah15

1 project • 1 follower

DHT22 Sensor with 16x2 LCD Screen

Things used in this project

Hardware components

Software apps and online services

Story

Schematics

Temp Sensor With LCD and Arduino

Code

LED With DHT22 Temp. Sensor

Credits

abshah15

Comments

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DHT22 Sensor with 16x2 LCD Screen

DHT22 Sensor with 16x2 LCD Screen

Things used in this project

Hardware components

Software apps and online services

Story

Schematics

Temp Sensor With LCD and Arduino

Code

LED With DHT22 Temp. Sensor

Credits

abshah15

Comments

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