---
title: "Arduino Ethernet and SD card shield (WIZnet W5100)"
url: "https://maker.wiznet.io/mason/projects/Arduino-Ethernet-and-SD-card-shield-WIZnet-W5100-by-mason/"
markdown_url: "https://maker.wiznet.io/mason/projects/Arduino-Ethernet-and-SD-card-shield-WIZnet-W5100-by-mason/md"
type: "UCC: User Created Content"
author: "mason"
author_url: "https://maker.wiznet.io/mason/"
original_author: "mason"
original_url: "https://www.espruino.com/arduino-w5100"
published: "2022-03-31"
language: "en"
hardware: ["WIZnet W5100"]
likes: 0
views: 388
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---

# Arduino Ethernet and SD card shield (WIZnet W5100)

> Arduino Ethernet and SD card shield (WIZnet W5100)

Original author: mason (source: https://www.espruino.com/arduino-w5100)

## Components

- **WIZnet W5100** x 1 ([docs](https://docs.wiznet.io/Product/Chip/Ethernet/W5100))

## Article

Standard Arduino Ethernet shields use the WIZnet W5100 chip, which provides hardware support for TCP/IP. The W5100 is supported out of the box by?[Pixl.js](https://www.espruino.com/Pixl.js) Most other offical Espruino boards have firmware with support for the?[WIZnet W5500](https://www.espruino.com/WIZnet)?and will not work with the W5100 without a special firmware build.

## Wiring[?](https://www.espruino.com/arduino-w5100#wiring)

The Ethernet shield shown above exposes the W5100 through pins on the Arduino 2x3 pin?`ICSP`?header (which isn't present on?[Pixl.js](https://www.espruino.com/Pixl.js)) rather than the standard Arduino footprint. To connect it up, you will need to add 3 wires to the shield (mirroring the connections there would be on an Arduino UNO board), connecting:

- ICSP MOSI to?`D11`

- ICSP MISO to?`D12`

- ICSP SCK to?`D13`

```
 ---------------------------------
|              D13  D12  D11      |
|              SCK MISO  MOSI     |
|                                  
| ETH                               |
| JACK                              |
|                                   |
|                        MISO ---   |
|                        SCK  MOSI  |
|                        ---- GND   |
|                                   |
|                         SD CARD   |
|                                   |
|                                   |
| RESET                            /
 ----------------------------------
```

The easiest method is to remove the?`ICSP`?header completely ![WIZnet W5100 Ethernet shield remove header](https://www.espruino.com/refimages/arduino-w5100_remove-header.jpg) and add wires on the underside of the board. ![WIZnet W5100 Ethernet shield add wires](https://www.espruino.com/refimages/arduino-w5100_add-wires.jpg) Now attach Pixl to shield ![Pixl attacched to WIZnet W5100 Ethernet shield](https://www.espruino.com/refimages/arduino-w5100_Pixl-adruion-w5100.jpg)

## Pinout[?](https://www.espruino.com/arduino-w5100#pinout)

This board has the following connections:

| Pin | Connection |
| --- | --- |
| D13 | SCK |
| D12 | MISO |
| D11 | MOSI |
| D10 | W5100 CS |
| D4 | SD Card CS |
| D2 | W5100 IRQ |

## Software[?](https://www.espruino.com/arduino-w5100#software)

## Ethernet[?](https://www.espruino.com/arduino-w5100#ethernet)

First, you need to set up communications with the WIZnet chip:

```
SPI1.setup({ mosi:D11, miso:D12, sck:D13 });
var eth = require("WIZnet").connect(SPI1, D10 /*CS*/);
```

Unlike the W5500 the W5100 doesn't come in a module with a pre-assigned MAC address set. You can either set one and then use DHCP to get an IP address:

```
eth.setIP({mac:"00:08:dc:ab:cd:ef"});
eth.setIP();
```

or can set the IP address manually:

```
eth.setIP({
  ip:"192.168.1.123",
  subnet:"255.255.255.0",
  gateway:"192.168.1.1",
  dns:"8.8.8.8",
  mac:"00:08:dc:ab:cd:ef"
});
```

Now you're ready to go - you can request a webpage:

```
require("http").get("http://www.pur3.co.uk/hello.txt", function(res) {
  res.on('data', function(d) {
    console.log("--->"+d);
  });
});
```

**Note:**?there is currently an issue in the W5100 library that causes Espruino to pause for 30 seconds when closing a socket, however everything else works. Or can even start a web server:

```
function pageHandler(req, res) {
  res.writeHead(200);
  res.end("Hello World");
}

require("http").createServer(pageHandler).listen(80);
console.log("Connect to http://"+eth.getIP().ip)
```

Functions that are available on?`eth`?are documented in?[the Ethernet Class](https://www.espruino.com/Reference#Ethernet) See the?[Internet](https://www.espruino.com/Internet)?page for more examples of things you can do on Espruino with an Internet connection.

## SD Card[?](https://www.espruino.com/arduino-w5100#sd-card)

All you need to do to set up the SD card is:

```
// Setup SPI - no need to call this if you've already set up Ethernet
SPI1.setup({ mosi:D11, miso:D12, sck:D13 });
// Configure the SD card
E.connectSDCard(SPI1, D4 /*CS*/);
```

Then:

```
// see what's on the device
console.log(require("fs").readdirSync());
// write
require("fs")writeFileSync("test.txt","Some Data");
// read
print(require("fs").readFileSync("test.txt"));
```

See?[the page on File IO](https://www.espruino.com/File+IO)?for more information.

---

Source: https://maker.wiznet.io/mason/projects/Arduino-Ethernet-and-SD-card-shield-WIZnet-W5100-by-mason/