Building an Industrial Field Switch/Gateway with Raspberry Pi and BE-IIS HAT++ Boards
The Problem
Many industrial systems still use established fieldbus interfaces such as CAN, RS-485 or Modbus. At the same time, Single Pair Ethernet is becoming more important, especially with 10BASE-T1L and 10BASE-T1S. This creates a practical question: How can engineers connect the old fieldbus world with the new Single Pair Ethernet world without building a complete custom gateway from scratch or spending a large budget on specialized equipment? One possible answer is to use a Raspberry Pi as a flexible Linux platform and extend it with modular BE-IIS HAT++ interface boards. Together with a web-based configuration and diagnostics tool, this creates a compact development platform for testing, diagnostics, protocol bridging and early migration projects between classic industrial interfaces and Single Pair Ethernet.
What Makes the BE-IIS System Simple?
The BE-IIS system is based on the standard Raspberry Pi HAT concept. Developers who already know the Raspberry Pi ecosystem can use a familiar platform and extend it with industrial interfaces.
But the system goes one step further.
BE-IIS HAT++ boards are designed for combination. Depending on the setup, up to five interfaces can be used in one system, and at least three identical interfaces can be combined in a typical stack. Installation is also kept simple. An installer and auto-detection mechanism help bring the system from assembled hardware to loaded device drivers in only a few minutes. Working on the Linux terminal is still possible, but it is not required for every task. A web-based configuration tool can be used to configure and diagnose the interfaces directly from a browser.
Typical functions include: * setting IP addresses * configuring 10BASE-T1S PLCA or CSMA mode * creating bridges * setting up traffic mirroring * running diagnostics * checking interface status
For advanced users, the system remains open and can still be configured with native Linux tools.
Available Interfaces
The BE-IIS HAT++ system provides several industrial interfaces that can be combined in one Raspberry Pi-based gateway.
All field interfaces are designed with galvanic isolation. This helps separate the Raspberry Pi and the Linux host system from the electrical conditions on the field side.
The hardware is built with a focus on reliable industrial electronics, robust interface circuits and suitable protection concepts. Depending on the interface, this includes protection against ESD, burst and surge events.
This makes the boards suitable not only for laboratory setups, but also for more demanding development, test and industrial prototype environments.
BE-IIS products are available through DigiKey:
https://www.digikey.com/en/supplier-centers/industrial-interface-solutions
All product documentation is published on the BE-IIS website. For each board, the product page provides access to the datasheet, schematic, layout view and 3D view.
This makes the hardware transparent and helps engineers evaluate the boards before using them in their own systems.
Product documentation:
https://www.be-iis.eu/products/
How to Get It Running
Getting the system running only takes a few minutes.
You need a Raspberry Pi with Raspberry Pi OS installed. If no system is available yet, create a new SD card image with the Raspberry Pi Imager on Windows or Linux.
Prepare the HAT++ stack before powering the system. There are no fixed stacking restrictions, but each HAT++ board must use a different Instance ID. Instance I must be present exactly once.
Example Raspberry Pi HAT++ stack with LAN, 10BASE-T1S, PoSPE, Modbus and UART interfaces
Figure 1: Example Raspberry Pi HAT++ stack with multiple industrial interfaces.
After power-on, assign the Instance ID of each HAT++ board by pressing the button on the board until the desired ID is selected.
Annotated BE-IIS HAT++ board showing the Instance ID configuration button
Figure 2: Example HAT++ board with annotated Instance ID button.
The Instance ID defines the position of each board in the stack.
The system uses this information to detect the connected boards and load the required configuration.
Overview of HAT++ Instance ID nodes
Figure 3: Overview of the HAT++ Instance ID concept.
Once the hardware preparation is done, log in to the Raspberry Pi. This can be done by SSH, display and keyboard, UART console or any other standard login method. Make sure the Raspberry Pi has a working network connection.
Clone the BE-IIS installer repository:
Run the installer:
cd be-iis-installer
./scripts/install/install-all.sh
Example output:
[INFO] Done
[INFO] Total scripts : 6
[INFO] Successful : 6
[INFO] Failed : 0
[INFO] --------------------------------------------------
[INFO] Installation complete.
[INFO] The following changes will become active after reboot:
[INFO] - systemd service
[INFO] - udev rules
[INFO] - module autoload / runtime setup
[INFO] --------------------------------------------------
Press ENTER to reboot now or CTRL+C to cancel…
For a gateway setup with two Raspberry Pi systems, the installation must be performed on both systems.
Verify System Integration
After reboot, the BE-IIS system integration log can be checked with:
journalctl -b | grep “BE-IIS”
Example output on a Raspberry Pi Zero 2 W:
BE-IIS ========================================
BE-IIS HAT++ System Integration
BE-IIS ========================================
BE-IIS [1/2] Scanning BE-IIS HAT++ EEPROMs…
BE-IIS Instance I (0-0050): HAT detected → BE-IIS-HPP-T1L-I
BE-IIS Instance I (0-0050): Base instance (overlay handled by HAT+ autodetect)
BE-IIS [2/2] Loading BE-IIS kernel modules…
BE-IIS Loading module: adin1110
BE-IIS HAT++ system integration complete.
Device Files and udev Rules
After installation and reboot, the BE-IIS interfaces are available as Linux device files on the Raspberry Pi.
The installer also adds udev rules so that BE-IIS devices get stable and readable names. All BE-IIS device names start with beiis.
The detected devices can be listed with:
ls /dev/ | grep beiis
This makes it easier to identify the installed HAT++ interfaces and use them from scripts, applications or diagnostic tools.
How to Use the Gateway/Switch
Linux specialists can already do many things directly with the device drivers and native Linux tools. Interfaces can be configured with standard tools, traffic can be captured with tcpdump and bridges or routing setups can be created manually.
But not every user is a Linux specialist. And even experienced users do not always want to type long terminal commands for basic configuration and diagnostics.
For this reason, BE-IIS also provides a web-based network configuration and diagnostics tool:
The tool provides access to the most important network functions directly from a browser. It does not replace the full Linux terminal, but it makes common gateway and switch tasks easier and faster.
Typical functions include:
- viewing detected network interfaces
- checking IP addresses and routes
- configuring Ethernet connections
- configuring 10BASE-T1S PLCA or CSMA mode
- creating and managing bridges
- setting up traffic mirroring
- running basic diagnostics
- capturing and analyzing traffic
Advanced users can still use the terminal at any time. The system remains a normal Linux system, so the full power of native Linux networking is still available when needed.
Installing the Web Tool
Clone the repository:
Enter the project directory:
cd be-iis-network-web
Install the web tool as a systemd service:
chmod +x install_be_iis_network_web.sh
sudo ./install_be_iis_network_web.sh
After installation, check the service status:
sudo systemctl status be-iis-network-web
The web interface can then be opened in a browser:
https://:8080/
Example:
From there, the Raspberry Pi-based gateway can be configured and diagnosed through the web interface instead of using only terminal commands.
Web Tool Impressions
Optional Web-Based Configuration
For users who do not want to configure everything manually on the Linux terminal, BE-IIS provides an open web-based configuration and diagnostics tool:
The software is currently experimental. The basic functions are tested, and it already allows many Linux network functions to be accessed from a web browser.
Typical functions include interface overview, IP configuration, bridge setup, diagnostics, traffic view, mirroring and 10BASE-T1S PLCA/CSMA configuration.
Advanced users can still use the full Linux terminal at any time.
BE-IIS network web dashboard
Figure X: Web-based overview of the detected network interfaces.
BE-IIS 10BASE-T1S configuration
Figure X: Example 10BASE-T1S configuration through the web interface.
Conclusion
The BE-IIS HAT++ system provides a modular way to build industrial gateway and field switch systems with a Raspberry Pi.
By combining a flexible Linux platform with stackable industrial interface boards, engineers can quickly create compact systems for testing, diagnostics, protocol bridging and technology evaluation.
The system can be used for:
- sniffing and analyzing network traffic
- bridging data between different interfaces
- diagnostic access to fieldbus systems
- Single Pair Ethernet testing, especially 10BASE-T1S with PLCA or CSMA
- interface stimulation during development and testing
- evaluating new industrial communication concepts
An open web-based configuration and diagnostics tool makes many network functions accessible from a browser. Advanced users can still use the full Linux terminal and standard Linux tools at any time.
The goal is to provide a practical development platform for connecting established fieldbus technologies with modern Ethernet-based interfaces such as Single Pair Ethernet.
Feedback is welcome.
What is missing? Which interfaces would be useful for your application? Do you see a need for a custom implementation?
Productlinks to parts from Brechel Electronic-Industrial Interface Systems (BE-IIS): Products
BE-IIS-HPP-MODBUS – Raspberry Pi MODBUS HAT++
BE-IIS-HPP-T1S – Raspberry Pi 10BASE-T1S HAT++
BE-IIS-HPP-CAN – Raspberry Pi CAN-FD-SIC HAT++
BE-IIS-HPP-T1L – Raspberry Pi 10BASE-T1L HAT++
Hint to a further article on their Website:
https://www.be-iis.eu/technology/BE-IIS-HPP-T1L/
Additional Reference
- ADIN1110 10BASE-T1L Ethernet MAC-PHY, Analog Devices / DigiKey
https://www.digikey.de/de/product-highlight/a/analog-devices/adin1110-10base-t1l-ethernet-mac-phy
About the Author
Philipp Brechel
Philipp Brechel is an electrical engineer and the founder of Brechel Electronic / Industrial Interface Systems.
He has many years of experience in electronics development for automotive hardware and has always had a strong interest in Linux-based systems.
With BE-IIS, he combines his professional hardware development experience with his passion for Linux, embedded systems and industrial communication interfaces.
BE-IIS focuses on modular industrial interface hardware for Raspberry Pi-based systems, Single Pair Ethernet, CAN FD, RS-485/Modbus and other field-level communication technologies.