W5100 Ethernet Network Shield with Arduino

Introduction

The world is rapidly progressing towards automation and connectivity, and Ethernet-based networks are playing a significant role in it. If you’re an Arduino enthusiast, you must have come across the W5100 Ethernet Network Shield, a compact and affordable add-on that provides network connectivity to Arduino boards.

In this article, we will explore the features, working, and applications of the “W5100 Ethernet Network Shield” and how it can help you build innovative projects.

What is W5100 Ethernet Network Shield?

The W5100 Ethernet Network Shield is a small add-on board that provides network connectivity to Arduino boards. It is equipped with a Wiznet W5100 Ethernet chip, which allows Arduino boards to connect to the internet or local network via Ethernet cable. The shield comes with an RJ45 Ethernet jack, a micro-SD card slot, and a reset button. It also has a set of digital pins that can be used for interfacing with other devices or sensors. The W5100 Ethernet Network Shield is compatible with most Arduino boards and can be easily connected to them using the standard Arduino headers. With this shield, you can create a wide range of internet-connected projects, such as web servers, IoT devices, and remote control systems.

Hardware Components

You will require the following hardware for Interfacing Ethernet Network Shield with Arduino.

Components	Value	Qty
Arduino UNO	–	1
USB Cable Type A to B	–	1
DC Power for Arduino	–	1
Jumper Wires	–	1

W5100 Ethernet Shield Pinout

Pin Name	Pin Description
D11, D12, D13 pin	Arduino communication is done using SPI bus through ICSP header so pin numbers on classic Arduino models are used for this purpose
D 50, and D 52	on Arduino Mega serve the same purpose.
D 10 pin	used and it’s a general-purpose input-output pin
D 4 pin	general purpose input output pin but it is used for SD cards.
D 2 pin	is named as INT on the Arduino board and is connected with INT pin of W5100
D 53	is although SPI pin but it cannot be used to select either W5100 or SD card it should be kept as an output or our SPI interface will not work.

Installing Arduino IDE

First, you need to install Arduino IDE Software from its official website Arduino. Here is a simple step-by-step guide on “How to install Arduino IDE“.

Installing Libraries

Before you start uploading a code, download and unzip the following libraries at /Program Files(x86)/Arduino/Libraries (default), in order to use the sensor with the Arduino board. Here is a simple step-by-step guide on “How to Add Libraries in Arduino IDE“.

• Ethernet2.h
• SPI.h

Code

Now copy the following code and upload it to Arduino IDE Software.

#include <SPI.h>
#include <Ethernet2.h>
 
// Enter a MAC address and IP address for your controller below.
// The IP address will be dependent on your local network.
// gateway and subnet are optional:
byte mac[] = {
  0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED
};
IPAddress ip(192, 168, 1, 177);
IPAddress gateway(192, 168, 1, 1);
IPAddress subnet(255, 255, 0, 0);
 
 
// telnet defaults to port 23
EthernetServer server(23);
boolean alreadyConnected = false; // whether or not the client was connected previously
 
void setup() {
  // initialize the ethernet device
  Ethernet.begin(mac, ip, gateway, subnet);
  // start listening for clients
  server.begin();
  // Open serial communications and wait for port to open:
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }
 
 
  Serial.print("Chat server address:");
  Serial.println(Ethernet.localIP());
}
 
void loop() {
  // wait for a new client:
  EthernetClient client = server.available();
 
  // when the client sends the first byte, say hello:
  if (client) {
    if (!alreadyConnected) {
      // clead out the input buffer:
      client.flush();
      Serial.println("We have a new client");
      client.println("Hello, client!");
      alreadyConnected = true;
    }
 
    if (client.available() > 0) {
      // read the bytes incoming from the client:
      char thisChar = client.read();
      // echo the bytes back to the client:
      server.write(thisChar);
      // echo the bytes to the server as well:
      Serial.write(thisChar);
    }
  }
}

Code Explanation

This Arduino code is a basic example of a chat server using an Ethernet connection.

The code begins with the inclusion of two libraries, “SPI.h” and “Ethernet2.h”. Then it declares some variables like MAC address, IP address, gateway address, subnet mask, and an Ethernet server object with a default port number of 23.

In the setup function, the Ethernet device is initialized with the provided MAC and IP addresses. The server object is then started to listen for incoming client connections, and the serial communication is initialized with a baud rate of 9600. Finally, the IP address of the server is printed on the serial monitor.

In the loop function, the code waits for incoming client connections. When a new client connects, the code checks if it’s a new client or an already connected one. If it’s a new client, it sends a “Hello, client!” message to the client. The code then listens for incoming data from the client and echoes it back to the client and the serial monitor.

This code is a simple example of how to create a basic chat server using an Ethernet connection with an Arduino board. By modifying this code, you can create more complex and functional networked applications for your projects.

Applications

Here are some applications of the W5100 Ethernet Network Shield:

• Web servers: You can use the shield to create a web server with an Arduino board, allowing you to host a website that can be accessed from anywhere on the internet.
• Internet of Things (IoT) devices: The shield can be used to create IoT devices that can send and receive data over the internet, allowing you to remotely monitor and control your devices.
• Home automation systems: The shield can be used to create a home automation system that allows you to control lights, fans, and other home appliances remotely.
• Data logging systems: You can use the shield to create data logging systems that collect and store data from sensors, and upload it to a web server or cloud-based platform for analysis.
• Industrial automation: The shield can be used in industrial automation applications to monitor and control machines and processes remotely.

Conclusion

The W5100 Ethernet Network Shield is an excellent tool for Arduino enthusiasts who want to add network connectivity to their projects. Its compact size, affordability, and easy-to-use interface make it an attractive choice for beginners and professionals alike.