---
title: "Connect Arduino to the Web using Ethernet Shield W5100"
url: "https://maker.wiznet.io/losel/projects/Connect-Arduino-to-the-Web-using-Ethernet-Shield-W5100-by-losel/"
markdown_url: "https://maker.wiznet.io/losel/projects/Connect-Arduino-to-the-Web-using-Ethernet-Shield-W5100-by-losel/md"
type: "UCC: User Created Content"
author: "losel"
original_author: "losel"
original_url: "https://www.aranacorp.com/en/connect-arduino-to-the-web-using-ethernet-shield-w5100/"
published: "2021-03-03"
language: "en"
likes: 0
views: 499
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---

# Connect Arduino to the Web using Ethernet Shield W5100

> Connect Arduino to the Web using Ethernet Shield W5100

Original author: losel (source: https://www.aranacorp.com/en/connect-arduino-to-the-web-using-ethernet-shield-w5100/)

## Article

## Hardware

- Computer

- ArduinoUNO

- USB A Male/B Male

- Ethernet cable RJ45

- Ethernet Shield W5100

## Operating principle of an Ethernet Shield W5100

The communication network uses the Ethernet which can be linked to local Wifi network. To access the Arduino board without having to connect to the Internet router, it is necessary to create a bridge between wifi and ethernet connection in your computer. For this, we must:

- Go to the Network and Sharing Center.

- Go to “Change adapter settings”

- Select Ethernet and Wifi/(internet source) and right click.

- Click “Create Bridge”.

In Windows, the control terminal, type “arp -a” to see the IP addresses used on the network. The Ethernet Shield W5100 uses Microchip W5100 as Ethernet controller.

## Schematics

The Ethernet Shield W5100 is compatible with the Arduino UNO and Mega microcontroller. The W5100 and SD card use the SPI bus to communicate with the Arduino board. The pin 10 is used to select the ethernet controller W5100, pin 9 as RESET to the W5100 and pin 4 to select the SD card module. In summary, the pins used are:

- 4 to select the SD card (SD_CS)

- 9 for the reset of the W5100 microchip (W5100_RST)

- 10 to select the W5100 microchip (W5100_CS)

- SPI bus: 11,12,13 pins on an Arduino UNO board/Duelmilanove. The pins 50, 51 and 52 for the Mega

## Code for an Ethernet Shield W5100

To communicate over the network, we need to use a particular protocol. This protocol is integrated in Arduino libraries dealing with WiFi communication.

- You need to connect the WiFi module or Ethernet network

- set a?**server**

- define a?**Customer**

Further details are in link below: <https://www.aranacorp.com/en/connect-arduino-to-the-web-using-ethernet-shield-w5100/>

---

Source: https://maker.wiznet.io/losel/projects/Connect-Arduino-to-the-Web-using-Ethernet-Shield-W5100-by-losel/