---
title: "PlatformIO: How to use RobotDyn Arduino Leonardo Ethernet W5500"
url: "https://maker.wiznet.io/viktor/projects/platformio%3A-how-to-use-robotdyn-arduino-leonardo-ethernet-w5500/"
markdown_url: "https://maker.wiznet.io/viktor/projects/platformio%3A-how-to-use-robotdyn-arduino-leonardo-ethernet-w5500/md"
type: "UCC: User Created Content"
author: "Technopolis"
author_url: "https://www.technopolis.tv/blog/2023/05/22/PlatformIO-How-to-use-RobotDyn-Arduino-Leonard-Ethernet-W5500/"
editor: "WIZnet"
editor_url: "https://maker.wiznet.io/"
original_author: "Technopolis"
original_url: "https://www.technopolis.tv/blog/2023/05/22/PlatformIO-How-to-use-RobotDyn-Arduino-Leonard-Ethernet-W5500/"
published: "2023-07-10"
language: "en"
likes: 0
views: 417
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---

# PlatformIO: How to use RobotDyn Arduino Leonardo Ethernet W5500

> PlatformIO: How to use RobotDyn Arduino Leonardo Ethernet W5500

Original author: Technopolis (source: https://www.technopolis.tv/blog/2023/05/22/PlatformIO-How-to-use-RobotDyn-Arduino-Leonard-Ethernet-W5500/)

## Article

Prevously I wrote about the madness I had with several [Ethernet Modules and Shields](https://www.technopolis.tv/W5100-Ethernet-Nightmares/).

Through my journey to find the “best” Arduino compatible *Ethernet Shield*, I found a very nice and promising Arduino Board with a built-in ethernet.

Since the price was decent, I decided to give **RobotDyn Arduino Leonardo Ethernet with W5500 Chip and PoE** a try. It’s based on the original *Arduino Leonardo ETH*.

I ordered two boards without PoE. Unfortunately the boards were laying around for a long time, because I couldn’t figure out how to use the ethernet functionality.

I used [PlatformIO](https://platformio.org/platformio-ide) and tried different ethernet libraries like `Ethernet`, `Ethernet2` and `Ethernet3` with no success.[1](https://www.technopolis.tv/blog/2023/05/22/PlatformIO-How-to-use-RobotDyn-Arduino-Leonard-Ethernet-W5500/#fn:fn-1)[2](https://www.technopolis.tv/blog/2023/05/22/PlatformIO-How-to-use-RobotDyn-Arduino-Leonard-Ethernet-W5500/#fn:fn-2)[3](https://www.technopolis.tv/blog/2023/05/22/PlatformIO-How-to-use-RobotDyn-Arduino-Leonard-Ethernet-W5500/#fn:fn-3)

I didn’t even bother to try out *Arduino IDE*. PlatformIO is in my opinion much more advanced and mature. I was about to give up after digging into `Arduino.h` and `pins_arduino.h` without any success and trying for hours different libraries and example sourcecodes that I came across online.

Finally I found some hints in a five year old and weird GitHub repository of RobotDyn.[4](https://www.technopolis.tv/blog/2023/05/22/PlatformIO-How-to-use-RobotDyn-Arduino-Leonard-Ethernet-W5500/#fn:fn-4)

## PlatformIO + RobotDyn Leonardo ETH

I uploaded a working UDP Server example to [Github](https://github.com/technopolistv/PlatformIO-RobotDyn-LeonardoETH). You can assign a *static IP address* and connect to it via `netcat` or other UDP client on port `8888`.

By pulling the `RST` pin 11 `HIGH` before `Ethernet.begin()` function, ethernet worked without any issues.

|  |
| --- |

| ```
//#define CS  4   // SD CS
#define SS  10  // W5500 CS
#define RST 11  // W5500 RST

pinMode(RST, OUTPUT);
digitalWrite(RST, HIGH);

Ethernet.begin(mac, ip);
``` |
| --- |

Optionally you can pull `SS` pin 10 `LOW` before `Ethernet.begin()` and `HIGH` after the function to select *Ethernet*. To switch to *SD* you need to pull `CS` pin 4 `LOW`. Unfortunately I didn’t had much time to test it myself.

## Conclusion

Personally I prefer *Leonardo Ethernet* over *Ethernet Shield* for Arduino Uno. The ethernet chip of the Leonardo Ethernet `W5500` differs to the Arduino Uno’s (Clone) Ethernet Shields `W5100` and has more functionalities.

Instead of the `ATmega328P` microcontroller of the Arduino Uno, Leonardo uses the `ATmega32u4` microchip. A main advantage is to program the *Arduino Leonardo* (and *Micro*) as a HID device.

In other words, we can build a Keyboard/Mouse device with Network connectivity for upcoming cool projects.

One of it will be a dual controller for Software Groundstations like *MissionPlaner* and *QGroundControl* that takes the inputs of a Joystick or Gamepad to control the vehicle.

With a press of a button we will be able to switch from a HID Joystick to a MAVLink standalone Hardware Groundstation via UDP packets.

Stay tuned!

---

Source: https://maker.wiznet.io/viktor/projects/platformio%3A-how-to-use-robotdyn-arduino-leonardo-ethernet-w5500/