--- title: "SPI-Ethernet Module W5500 Usage Manual for mros2-esp32" url: "https://maker.wiznet.io/lawrence/projects/spi-ethernet-module-w5500-usage-manual-for-mros2-esp32/" markdown_url: "https://maker.wiznet.io/lawrence/projects/spi-ethernet-module-w5500-usage-manual-for-mros2-esp32/md" type: "UCC: User Created Content" author: "yamati" author_url: "https://qiita.com/yamati-kz/items/06793ebeb07a6875bcd7" editor: "WIZnet" editor_url: "https://maker.wiznet.io/" original_author: "yamati" original_url: "https://qiita.com/yamati-kz/items/06793ebeb07a6875bcd7" published: "2025-09-24" language: "en" likes: 0 views: 5078 comments: 0 source: "WIZnet Makers (https://maker.wiznet.io/)" --- # SPI-Ethernet Module W5500 Usage Manual for mros2-esp32 > SPI-Ethernet Module W5500 Usage Manual for mros2-esp32 Original author: yamati (source: https://qiita.com/yamati-kz/items/06793ebeb07a6875bcd7) ## Documents and links - [Github](https://github.com/espressif/esp-idf/tree/master/examples/ethernet/basic) (code) ## Article ## A Step-by-Step Guide to Creating a Wired mros-Esp32 Node with the WIZnet W5500 This guide provides detailed instructions for connecting an `mros-esp32` node to a stable, low-latency wired network using the WIZnet W5500 SPI-to-Ethernet module. By replacing a potentially unstable Wi-Fi connection with a wired one, you can significantly improve the reliability and performance of your robotics projects. This project leverages the W5500's hardware TCP/IP stack to offload network processing from the ESP32, ensuring high-speed and stable communication for mros-esp32 topics and services. With a few configuration changes, you can easily switch the mros-esp32 networking interface from Wi-Fi to Ethernet and test it immediately with the `echoback_string` example. ### What is ROS 2 ? - ROS 2 is an open-source framework for developing robot software applications. - It acts as communication middleware, helping a robot's various programs (nodes) exchange data with one another. - It is the next-generation version with improved performance and stability, making it suitable for real-time control, multi-robot systems, and commercial products. #### Micro-ROS #### ## 1. Prerequisites Hardware Components Before you begin, make sure you have all the necessary hardware and software components. #### Hardware Components⚙️ 1. **ESP32-S3 Development Board:** An `ESP32-S3-DevKitC-1` is used in this guide. 2. **WIZnet W5500 Module:** The `WIZ850io` module is recommended as it's a compact board featuring the W5500 chip. 3. **External 3.3V Power Supply:** A dedicated power source for the W5500 module is highly recommended to prevent instability. 4. **Jumper Wires & Breadboard:** For connecting the components. 5. **Ethernet Cable & LAN Connection:** To connect your project to a network switch, router, or PC. #### Software & Services💻 1. **Ubuntu:** Ubuntu 22.04 is used as the development environment. 2. **ESP-IDF v5.x:** The Espressif IoT Development Framework. Ensure it is properly installed and configured. 3. **mros-esp32:** The project files for mros-esp32 on the ESP32, including the required Ethernet sample code ([PR #27](https://www.google.com/search?q=https://github.com/mROS-base/mros2-esp32/pull/27) 4. **idf.py CLI:** The command-line interface for managing ESP-IDF projects. #### ## 2. Hardware Setup & Wiring Properly connecting the ESP32-S3 to the WIZ850io module is the first critical step. The communication is handled over the SPI protocol. Follow this wiring diagram carefully. **Pay special attention to the power supply**—powering the WIZ850io directly from the ESP32's 3.3V pin can cause the module to reset unexpectedly. Using a stable external 3.3V source is the best practice. | ESP32-S3-DevKitC-1 Pin | WIZ850io (W5500) Pin | Description | | --- | --- | --- | | **GPIO 11** | `MOSI` | Master Out, Slave In | | **GPIO 13** | `MISO` | Master In, Slave Out | | **GPIO 12** | `SCLK` | SPI Clock | | **GPIO 10** | `SCS` | SPI Chip Select | | **GPIO 9** | `RESET` | W5500 Reset Control | | **3.3V (External)** | `3.3V` | **Use External Power** | | **GND** | `GND` | Common Ground | ![](https://maker.wiznet.io/upload/ckeditor5/447083964%5F1758741175%2Epng) #### ## 3. Software Configuration With the hardware wired, the next step is to configure the `mros-esp32` project to use the SPI-Ethernet interface instead of Wi-Fi. ![](https://maker.wiznet.io/upload/ckeditor5/447083964%5F1758743231%2Epng) ![](https://maker.wiznet.io/upload/ckeditor5/447083964%5F1758743290%2Epng) 1. **Navigate to your project directory** in the terminal. 2. **Launch the configuration menu** by running the following command: idf.py menuconfig 3. **Configure the network interface** by navigating to the following path: `mros-esp32` → `Network Interface` → Select `Ethernet-SPI` 4. **Set up the Ethernet driver** in the next menu: `Example Ethernet Configuration` → `SPI Ethernet` → `Enable` 5. **Assign the Reset Pin** to match your hardware wiring: `PHY Reset GPIO number` → Enter `9 `Save your changes and exit `menuconfig`. #### **Code Initialization Snippet** The ESP-IDF Ethernet driver makes initialization straightforward. The configuration you just set in `menuconfig` is used by code like this to set up the W5500's MAC (Media Access Control) and PHY (Physical) layers and install the driver. ```cpp // Summary of the initialization process in the application code // 1. Define default MAC and PHY configurations. eth_mac_config_t mac_config = ETH_MAC_DEFAULT_CONFIG(); eth_phy_config_t phy_config = ETH_PHY_DEFAULT_CONFIG(); // 2. Configure the SPI device interface. spi_device_interface_config_t spi_cfg = { // ... SPI pin settings are configured here based on menuconfig ... }; // 3. Create new MAC and PHY instances for the W5500. esp_eth_mac_t *mac = esp_eth_mac_new_w5500(&spi_cfg, &mac_config); esp_eth_phy_t *phy = esp_eth_phy_new_w5500(&phy_config); // 4. Combine MAC and PHY into a default Ethernet configuration. esp_eth_config_t eth_config = ETH_DEFAULT_CONFIG(mac, phy); // 5. Install the Ethernet driver. esp_eth_handle_t eth_handle = NULL; ESP_ERROR_CHECK(esp_eth_driver_install(ð_config, ð_handle)); ``` #### ## 4. Build, Flash, and Test Now you're ready to build the firmware, flash it to your ESP32, and test the mros-esp32 communication. ![](https://maker.wiznet.io/upload/ckeditor5/447083964%5F1758743262%2Epng) 1. **Build the project** using the following command. If you've previously built for Wi-Fi, run `idf.py fullclean` first to avoid build errors. **idf.py build ** 2. **Flash the firmware** to the ESP32-S3 (make sure it's connected via USB): **idf.py -p /dev/ttyUSB0 flash** Replace `/dev/ttyUSB0` with your device's serial port. 3. **Monitor the output** to see the device connect to the network and start the mros-esp32 node: **idf.py monitor** 4. **Test the connection** using the `echoback_string` example. On your PC (which should have mros-esp32 2 installed and be on the same network), publish a message to the `to_mag` topic. The ESP32 node will receive it and echo it back on the `to_linux` topic. You should see the message appear on your PC, confirming a successful round trip. #### ## 5. Performance and Benefits By switching to a wired connection with the W5500, you can expect significant performance gains and stability. **Low Latency:** Average ping times can drop to **less than 1 ms**, which is over 10 times faster than a typical Wi-Fi connection. **High Throughput:** `iperf` tests show TCP throughput reaching **~40 Mbps**, making it suitable for high-bandwidth ROS 2 data. **Reliability:** In a 30-minute `ROS 2 topic echo` test, there was **0% packet loss**. This stability is crucial for robotics applications where dropped messages can lead to failures. The diagram below shows how ROS 2 DDS frames are sent directly over the wired interface, reducing the software buffering and wireless-related jitter that can affect Wi-Fi. ![](https://maker.wiznet.io/upload/ckeditor5/447083964%5F1758741626%2Epng) #### ## 6. Troubleshooting and Lessons Learned Here are solutions to common challenges you might encounter during setup. ![](https://maker.wiznet.io/upload/ckeditor5/447083964%5F1758741646%2Epng) #### ## 7. Future Improvements This project provides a solid foundation. Here are a few ways it could be enhanced: **Power-over-Ethernet (PoE):** Add a PoE HAT to deliver both power and data over a single Ethernet cable. **IPv6 Support:** Upgrade the hardware to the WIZnet W6100 chip to add support for IPv6. **QoS Optimization:** Fine-tune the mros-esp32 Quality of Service (QoS) profiles for different types of ROS2 data to optimize real-time performance. --- Source: https://maker.wiznet.io/lawrence/projects/spi-ethernet-module-w5500-usage-manual-for-mros2-esp32/