Temperature and Humidity display on 16X2 LCD with DHT11 Sensor [ARDUINO]

Hello. Recently I purchased a couple of sensors to use with  my Arduino. One of them is the DHT11 Temperature and Humidity sensor. This sensor is a cheap one. I got it in India for around $1.5. I'll mention the links if you want.

What this project does?
Displays the temperature (in Centigrade) and relative humidity (in %) received from the DHT11 sensor on the 16X2 LCD.

Let's know the basics!
"DHT11 Temperature & Humidity Sensor features a temperature & humidity sensor complex with a calibrated digital  signal output. By using  the exclusive digital-signal-acquisition technique  and  temperature  &  humidity  sensing  technology,  it  ensures  high  reliability and excellent  long-term  stability.  This  sensor  includes  a  resistive-type  humidity  measurement component  and  an  NTC  temperature  measurement  component,  and  connects  to  a  high-performance  8-bit microcontroller,  offering  excellent  quality,  fast  response,  anti-interference ability and cost-effectiveness."

Source: http://www.exp-tech.de/

SPECS:

Relative humidity
Resolution: 16Bit
Repeatability: ±1% RH
Accuracy: At 25℃ ±5% RH
Interchangeability: fully interchangeable
Response time: 1 / e (63%) of 25℃ 6s
1m / s air 6s
Hysteresis: <± 0.3% RH
Long-term stability: <± 0.5% RH / yr in
Temperature
Resolution: 16Bit
Repeatability: ±0.2℃
Range: At 25℃ ±2℃
Response time: 1 / e (63%) 10S
Electrical Characteristics
Power supply: DC 3.5～5.5V
Supply Current: measurement 0.3mA standby 60μ A
Sampling period: more than 2 seconds

Pin Description:
1. VCC power supply 3.5～5.5V DC
2. DATA serial data, a single bus
3. NC, empty pin
4. GND ground, the negative power

From now on, forget about the pin 3.

Materials Required:
1. A DHT11 Sensor
2. Arduino
3. Jumpers
4. One 16X2 LCD
5. Three 1K and one 10K resistor.
6. Breadboard
7. and ofcourse, a PC with Arduino IDE installed!


Procedure:
Hardware part:
1. Connect the components as shown.

REFERENCE:

[Click to enlarge]

Software part:
1. Download this library: DHT
2. Extract the zip and you'll get a folder named: "DHT"
3. Copy this folder to [My Documents/Arduino/libraries]
4. Upload the sketch given below.
5. Power on the Arduino.

Sketch:

/* 
 * ON PUBLIC DOMAIN
 * Author         : Nitish Dash
 * Name           : Temperature and Humidity on 16X2 LCD with DHT11 Sensor
 * Created        : 12/26/2014
 * Webpage        : http://goo.gl/W5iB30
 * Author Email   : nitishdash95@gmail.com
 * Author Website : http://www.nitishdash.com/
 **** DONOT COPY AND PLAGIARATE WITHOUT THE AUTHOR'S PERMISSIONS ****
 */
 
#include 
#include 
#define dht_dpin A0
dht DHT;
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
//this section is for the symbol of degree
byte deg[8] = {
 0b01110,
 0b01010,
 0b01110,
 0b00000,
 0b00000,
 0b00000,
 0b00000,
 0b00000
};

void setup() { //initialise for at least 2s
  lcd.begin(16, 2);
  lcd.print("INITIALISING");
  delay(500);
  lcd.print(".");
  delay(500);
  lcd.print(".");  
  delay(500);
  lcd.print(".");
  delay(500);
  lcd.print(".");  
  delay(500);
  lcd.createChar(0, deg);
}
void loop()
{
 DHT.read11(dht_dpin); 
 lcd.clear();
 lcd.setCursor(0, 0);
 lcd.print(" TEMP    : ");
 lcd.print((int)DHT.temperature);
 lcd.write((uint8_t)0);
 lcd.print("C");
 lcd.setCursor(0, 1);
 lcd.print(" HUMIDITY: ");
 lcd.print((int)DHT.humidity);
 lcd.print(" %");
 delay(1000); //modify but don't delay for less than 1s
}

NOTE: Please remove the line 58 from the code while uploading.
How this works (Algorithm):

The arduino receives the analog signal from the DHT11 sensor via A0 pin. The received signal is interpreted and processed by the library. The arduino then prints the message and measurement of temperature and relative humidity every 1s.

To test the sensor, try touching the sensor.
NOTE: Keep the sensor in normal conditions. Don't use it in excessively humid atmosphere or subject it to direct sunlight.

Video:
Coming soon.....

Downloads:
1. sketch.ino
2. Breadboard schematics

3. DHT11 Datasheet
4. 16X2 LCD Datasheet

5. DHT11 Library

Any doubts? Feel free to leave a comment.