Monitoring temperature, humidity, and light using Node.js with Arduino Ethernet

In the preceding section, we showed how to monitor our Arduino via Wi-Fi using the CC3000 module; now we will use another important module: Ethernet Shield. The hardware connection of the part is similar to the following image:

Code for the application of the Arduino Ethernet shield

You can now either copy the code inside a file called Monitor_Ethernet.ino, or just get the complete code from the folder for this project; you need to use the Arduino  IDE.

The following are the libraries included in the program:

#include <SPI.h> 
#include <Ethernet.h> 
#include <aREST.h> 
#include <avr/wdt.h> 

Include the library for the DHT11 sensor:

#include "DHT.h" 

We define the pins for the temperature and humidity sensor:

#define DHTPIN 7  
#define DHTTYPE DHT11 

We have the instance of the sensor:

DHT dht(DHTPIN, DHTTYPE); 

We register the MAC address for the device...