Arduino UNO R4 - Ethernet Module
This guide shows you how to connect the Arduino UNO R4 to the internet or your local network using the W5500 Ethernet module. We will discuss the following details:
- How to connect Arduino UNO R4 with W5500 Ethernet Module
- How to program Arduino UNO R4 to Make HTTP Requests via Ethernet
- How to create a Basic Web Server on Arduino UNO R4 via Ethernet
Hardware Preparation
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Additionally, some of these links are for products from our own brand, DIYables.
Overview of W5500 Ethernet module
The W5500 Ethernet module offers two interfaces:
- RJ45 Ethernet interface: Connect to a router or switch using an Ethernet cable.
- SPI interface: Connect to an Arduino UNO R4 board using this interface. It includes 10 pins:
- NC pin: Leave this pin unconnected.
- INT pin: Leave this pin unconnected.
- RST pin: This is the reset pin. Connect it to the EN pin on the Arduino UNO R4.
- GND pin: Connect this pin to the GND pin on the Arduino UNO R4.
- 5V pin: Connect this pin to the 5V pin on the Arduino UNO R4.
- 3.3V pin: Leave this pin unconnected.
- MISO pin: Connect this pin to the SPI MISO pin on the Arduino UNO R4.
- MOSI pin: Connect this pin to the SPI MOSI pin on the Arduino UNO R4.
- SCS pin: Connect this pin to the SPI CS pin on the Arduino UNO R4.
- SCLK pin: Connect this pin to the SPI SCK pin on the Arduino UNO R4.
image source: diyables.io
Wiring Diagram between Arduino UNO R4 and W5500 Ethernet module
This image is created using Fritzing. Click to enlarge image
See The best way to supply power to the Arduino Uno R4 and other components.
Arduino UNO R4 code for Ethernet Module - Making HTTP request via Ethernet
This code functions as a web client. It sends HTTP requests to the web server at http://example.com/.
/*
* This Arduino UNO R4 code was developed by newbiely.com
*
* This Arduino UNO R4 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-uno-r4/arduino-uno-r4-ethernet-module
*/
#include <SPI.h>
#include <Ethernet.h>
// replace the MAC address below by the MAC address printed on a sticker on the Arduino Shield 2
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
EthernetClient client;
int HTTP_PORT = 80;
String HTTP_METHOD = "GET"; // or POST
char HOST_NAME[] = "example.com";
String PATH_NAME = "/";
void setup() {
Serial.begin(9600);
delay(1000);
Serial.println("Arduino Uno R4 - Ethernet Tutorial");
// initialize the Ethernet shield using DHCP:
if (Ethernet.begin(mac) == 0) {
Serial.println("Failed to obtaining an IP address");
// check for Ethernet hardware present
if (Ethernet.hardwareStatus() == EthernetNoHardware)
Serial.println("Ethernet shield was not found");
// check for Ethernet cable
if (Ethernet.linkStatus() == LinkOFF)
Serial.println("Ethernet cable is not connected.");
while (true)
;
}
// connect to web server on port 80:
if (client.connect(HOST_NAME, HTTP_PORT)) {
// if connected:
Serial.println("Connected to server");
// make a HTTP request:
// send HTTP header
client.println(HTTP_METHOD + " " + PATH_NAME + " HTTP/1.1");
client.println("Host: " + String(HOST_NAME));
client.println("Connection: close");
client.println(); // end HTTP header
while (client.connected()) {
if (client.available()) {
// read an incoming byte from the server and print it to serial monitor:
char c = client.read();
Serial.print(c);
}
}
// the server's disconnected, stop the client:
client.stop();
Serial.println();
Serial.println("disconnected");
} else { // if not connected:
Serial.println("connection failed");
}
}
void loop() {
}
Detailed Instructions
Follow these instructions step by step:
- If this is your first time using the Arduino Uno R4 WiFi/Minima, refer to the tutorial on setting up the environment for Arduino Uno R4 WiFi/Minima in the Arduino IDE.
- Connect the Ethernet module to your Arduino UNO R4 according to the provided diagram
- Connect the Ethernet module to your your router or switch by using an Ethernet cable.
- Connect the Arduino Uno R4 board to your computer using a USB cable.
- Open the Arduino IDE on your computer.
- Select the appropriate Arduino Uno R4 board (e.g., Arduino Uno R4 Minima) and COM port.
- Click on the Libraries icon on the left side of the Arduino IDE.
- In the search box, type “Ethernet” and locate the Ethernet library by Various.
- Press the Install button to add the Ethernet library.
- Open the Serial Monitor in the Arduino IDE.
- Copy the given code and paste it into the Arduino IDE.
- Click the Upload button in the Arduino IDE to send the code to the Arduino Uno R4.
- To view the output, look at the Serial Monitor where the results will be displayed as indicated.
COM6
Arduino UNO R4 - Ethernet Tutorial
Connected to server
HTTP/1.1 200 OK
Accept-Ranges: bytes
Age: 208425
Cache-Control: max-age=604800
Content-Type: text/html; charset=UTF-8
Date: Fri, 12 Jul 2024 07:08:42 GMT
Etag: "3147526947"
Expires: Fri, 19 Jul 2024 07:08:42 GMT
Last-Modified: Thu, 17 Oct 2019 07:18:26 GMT
Server: ECAcc (lac/55B8)
Vary: Accept-Encoding
X-Cache: HIT
Content-Length: 1256
Connection: close
<!doctype html>
<html>
<head>
<title>Example Domain</title>
<meta charset="utf-8" />
<meta http-equiv="Content-type" content="text/html; charset=utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
</head>
<body>
<div>
<h1>Example Domain</h1>
<p>This domain is for use in illustrative examples in documents. You may use this
domain in literature without prior coordination or asking for permission.</p>
<p><a href="https://www.iana.org/domains/example">More information...</a></p>
</div>
</body>
</html>
disconnected
Autoscroll
Clear output
9600 baud
Newline
※ NOTE THAT:
If another device on the same network shares your MAC address, there may be issues.
Arduino UNO R4 code for Ethernet Module - Web Server
The code below turns the Arduino UNO R4 into a web server. This server sends a simple webpage to internet browsers.
/*
* This Arduino UNO R4 code was developed by newbiely.com
*
* This Arduino UNO R4 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-uno-r4/arduino-uno-r4-ethernet-module
*/
#include <SPI.h>
#include <Ethernet.h>
// replace the MAC address below by the MAC address printed on a sticker on the Arduino Shield 2
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
EthernetServer server(80);
void setup() {
Serial.begin(9600);
delay(1000);
Serial.println("Arduino Uno R4 - Ethernet Tutorial");
// initialize the Ethernet shield using DHCP:
if (Ethernet.begin(mac) == 0) {
Serial.println("Failed to obtaining an IP address");
// check for Ethernet hardware present
if (Ethernet.hardwareStatus() == EthernetNoHardware)
Serial.println("Ethernet shield was not found");
// check for Ethernet cable
if (Ethernet.linkStatus() == LinkOFF)
Serial.println("Ethernet cable is not connected.");
while (true)
;
}
server.begin();
Serial.print("Arduino Uno R4 - Web Server IP Address: ");
Serial.println(Ethernet.localIP());
}
void loop() {
// listen for incoming clients
EthernetClient client = server.available();
if (client) {
Serial.println("new client");
// an HTTP request ends with a blank line
bool currentLineIsBlank = true;
while (client.connected()) {
if (client.available()) {
char c = client.read();
Serial.write(c);
// if you've gotten to the end of the line (received a newline
// character) and the line is blank, the HTTP request has ended,
// so you can send a reply
if (c == '\n' && currentLineIsBlank) {
// send a standard HTTP response header
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println("Connection: close"); // the connection will be closed after completion of the response
client.println();
client.println("<!DOCTYPE HTML>");
client.println("<html>");
client.println("<body>");
client.println("<h1>Arduino Uno R4 - Web Server with Ethernet</h1>");
client.println("</body>");
client.println("</html>");
break;
}
if (c == '\n') {
// you're starting a new line
currentLineIsBlank = true;
} else if (c != '\r') {
// you've gotten a character on the current line
currentLineIsBlank = false;
}
}
}
// give the web browser time to receive the data
delay(1);
// close the connection:
client.stop();
Serial.println("client disconnected");
}
}
Detailed Instructions
- Copy the above code and paste it into Arduino IDE.
- Click the Upload button in Arduino IDE to upload the code to Arduino Uno R4.
- Check the result on Serial Monitor, it will display as follows:
COM6
Arduino UNO R4 - Ethernet Tutorial
Arduino UNO R4 - Web Server IP Address: 192.168.0.2
Autoscroll
Clear output
9600 baud
Newline
- Copy the IP address given above and enter it into your web browser's address bar. You will see a simple webpage displayed by the Arduino UNO R4.
