--- title: "Arduino Webserver with W5500 Shield" url: "https://maker.wiznet.io/junlee0615/projects/arduino-webserver-with-w5500-shield/" markdown_url: "https://maker.wiznet.io/junlee0615/projects/arduino-webserver-with-w5500-shield/md" type: "UCC: User Created Content" author: "E" author_url: "https://arduinodiy.wordpress.com/2024/04/29/arduino-webserver-with-w5500-shield/" editor: "WIZnet" editor_url: "https://maker.wiznet.io/" original_author: "E" original_url: "https://arduinodiy.wordpress.com/2024/04/29/arduino-webserver-with-w5500-shield/" published: "2025-08-28" language: "en" tags: ["Arduino", "W5500", "Ethernet", "Webserver", "DS18B20"] hardware: ["Arduino Ethernet Shield 2", "Arduino UNO", "DFRobot Gravity: DS18B20 Temperature Sensor (Arduino Compatible)"] likes: 0 views: 3349 comments: 0 source: "WIZnet Makers (https://maker.wiznet.io/)" --- # Arduino Webserver with W5500 Shield > Build a nostalgic Arduino webserver using the WIZnet W5500 shield and a DS18B20 sensor to serve live temperature over HTTP. Original author: E (source: https://arduinodiy.wordpress.com/2024/04/29/arduino-webserver-with-w5500-shield/) ## Components - **Arduino Ethernet Shield 2** x 1 ([docs](https://docs.arduino.cc/hardware/ethernet-shield-rev2)) - **Arduino UNO** x 1 ([docs](https://www.farnell.com/datasheets/1682209.pdf)) - **DFRobot Gravity: DS18B20 Temperature Sensor (Arduino Compatible)** x 1 ([docs](https://www.dfrobot.com/wiki/index.php/Gravity:_DS18B20_Temperature_Sensor_%28Arduino_Compatible%29_V2_SKU:_DFR0024)) - Software: **Arduino IDE** ([docs](https://www.arduino.cc/en/software)) ## Article Arduino W5500 Webserver with DS18B20 — Simple Hardware TCP/IP Temperature Page ## Introduction This project revives a classic: an Arduino webserver that displays live temperature readings in a browser. Using the **WIZnet W5500** Ethernet shield for hardware TCP/IP and a **DS18B20** temperature sensor on the OneWire bus, we serve a minimal HTML page that anyone on the local network can view. ## WIZnet Product Integration The **W5500** handles TCP/IP and Ethernet packet processing in hardware, minimizing MCU overhead. The shield connects to Arduino over **SPI** (ICSP header), letting the sketch focus on sensor reading and string formatting. A simple **EthernetServer** on port **80** responds to HTTP requests and prints the current temperature. ## Technical Implementation ### Wiring **DS18B20 → ArduinoDQ (data)** → **D2** (OneWire bus) **VDD** → **5V** (or 3.3V per sensor spec) **GND** → **GNDPull‑up**: 4.7 kΩ between **DQ** and **VDDW5500 Shield** Stacked on Arduino; uses **SPI via ICSP**. Default chip‑selects (for reference): **D10** for Ethernet, **D4** for SD (SD unused here). ![Generated image](https://sdmntprwestus2.oaiusercontent.com/files/00000000-ff1c-61f8-b123-f18b5108d0e8/raw?se=2025-08-27T23%3A25%3A27Z&sp=r&sv=2024-08-04&sr=b&scid=d0bcf911-bbc8-5579-8f34-00d4e0a45bcc&skoid=5c72dd08-68ae-4091-b4e1-40ccec0693ae&sktid=a48cca56-e6da-484e-a814-9c849652bcb3&skt=2025-08-27T20%3A19%3A13Z&ske=2025-08-28T20%3A19%3A13Z&sks=b&skv=2024-08-04&sig=M4gL3A5YiCPy54oZvNyKYmLOheOOJXNymvcv7FXvEq0%3D) ### Network Setup **Static IP** (in sketch): `Ethernet.begin(mac, ip);` Optional **DHCP**: replace with `Ethernet.begin(mac);` to obtain an address from your router. Access from a browser at `http:///`. ### Sketch (Complete) #include <Ethernet.h> // Library for W5500-based Ethernet shield Serial.begin(9600); // Start the serial communication for debugging // Set up the Ethernet shield with a fixed MAC address and IP address byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; // MAC address IPAddress ip(192, 168, 1, 177); // Local IP address (adjust as needed for your network) // Start the Ethernet and the server Ethernet.begin(mac, ip); server.begin(); Serial.print("Server is at "); Serial.println(Ethernet.localIP()); // Start the temperature sensor sensors.begin(); } void loop() { // Check for incoming client connections EthernetClient client = server.available(); if (client) { Serial.println("New client connected"); boolean currentLineIsBlank = true; while (client.connected()) { if (client.available()) { char c = client.read(); // If the request is complete (double newline), send the response if (c == '\n' && currentLineIsBlank) { sensors.requestTemperatures(); // Request temperature float temperature = sensors.getTempCByIndex(0); // Get temperature in Celsius // Send the HTTP response headers client.println("HTTP/1.1 200 OK"); client.println("Content-Type: text/html"); client.println("Connection: close"); // Connection will close after this response client.println(); // Send the HTML content with temperature client.println("<!DOCTYPE HTML>"); client.println("<html>"); client.println("<h1>Temperature Monitor</h1>"); client.print("<p>Temperature: "); client.print(temperature); client.println(" °C</p>"); client.println("</html>"); break; } if (c == '\n') { currentLineIsBlank = true; } else if (c != '\r') { currentLineIsBlank = false; } } } // Close the connection with the client client.stop(); Serial.println("Client disconnected"); } } ## Core Features and Behavior **Static IP webserver** on port **80** serving a minimal HTML page. **Live temperature** read from DS18B20 on each HTTP request. Connection is **closed** after responding, keeping the server simple and robust. ## Code Analysis `EthernetServer server(80)` creates the TCP listener; `server.available()` yields a client when connected. A double newline (`\r\n\r\n`) marks the end of the HTTP request headers; the code checks for a blank line using `currentLineIsBlank`. Before responding, `sensors.requestTemperatures()` triggers a OneWire conversion; `getTempCByIndex(0)` fetches the first sensor’s reading. Response includes essential HTTP headers and a minimal HTML body. ## Applications and Use Cases Lab dashboards and classroom demos. Local environment monitoring on wired networks. Embedding into larger projects as a simple status page. ## Troubleshooting & Tips **IP/Subnet**: Ensure the static IP matches your LAN subnet and isn’t already in use. **DHCP**: If preferred, switch to DHCP (router must support it) and print the assigned IP via `Ethernet.localIP()`. **Sensor wiring**: DS18B20 requires a **4.7 kΩ** pull‑up on DQ; noisy/long cables may need careful routing. **Mega compatibility**: When using Arduino Mega, keep **pin 53** as **OUTPUT** for SPI to work. **SD coexistence**: If the shield’s SD is unused, keep CS (D4) **HIGH**. If used, only one device on SPI may be active at a time. ## Conclusion Using the **WIZnet W5500** Ethernet shield and a **DS18B20** sensor, this project demonstrates a clean, nostalgic Arduino webserver pattern. With hardware TCP/IP offload and a tiny HTML page, it’s a perfect starting point for wired IoT dashboards, status pages, or classroom exercises. --- Source: https://maker.wiznet.io/junlee0615/projects/arduino-webserver-with-w5500-shield/