> For the complete documentation index, see [llms.txt](https://reacoda.gitbook.io/molemi-iot/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://reacoda.gitbook.io/molemi-iot/introducing-the-nodemcu/display-the-dht11-sensor-reading-on-a-web-server-using-nodemcu./installing-dht-library-on-the-esp8266/installing-the-asynchronous-web-server-library/the-code.md).

# The Code

We’ll program the ESP8266 using Arduino IDE, so you must have the ESP8266 add-on installed in your Arduino IDE.

Open your Arduino IDE and follow the step-by-step explanation of the code:

1. The first thing that you need to is to include all the libraries at the beginning:<br>

```
#include <Arduino.h>
#include <ESP8266WiFi.h>
#include <Hash.h>
#include <ESPAsyncTCP.h>
#include <ESPAsyncWebServer.h>
#include <Adafruit_Sensor.h>
#include <DHT.h>
```

2\. Setup your network credentials:

```
const char* ssid = "REPLACE_WITH_YOUR_SSID";
const char* password = "REPLACE_WITH_YOUR_PASSWORD";
```

3\. Declare the GPIO pin that the DHT11 sensor is connected to. In our case we connected it to the GPIO 5 (D1).

```
#define DHTPIN 5     // Digital pin connected to the DHT sensor
```

Now you have to select the DHT type that you will be using. In our case we are using the DHT11.

```
#define DHTTYPE DHT1   // DHT 11 (AM2302)
```

Instantiate a DHTobject with the type and pin defined earlier.

```
DHT dht(DHTPIN, DHTTYPE);
```

Create an AsyncWebServerobject on port 80.

```
AsyncWebServer server(80);
```

Create float variables to hold the current temperature and humidity values. The temperature and humidity are updated in the loop().

```
float t = 0.0;
float h = 0.0;
```

Create timer variables needed to update the temperature readings every 10 seconds.

```
unsigned long previousMillis = 0;    // will store last time DHT was updated

// Updates DHT readings every 10 seconds
const long interval = 10000; 
```