The convergence of wireless networking and CAN Bus technology has fundamentally changed how engineers design embedded systems. For years, CAN Bus networks operated as isolated, wired communication systems found in vehicles, industrial equipment, agricultural machinery, and marine electronics. While they excel at reliable real-time communication, accessing data often required a physical connection through a CAN interface or data logger.

The ESP32 family of microcontrollers changes that equation. By combining an integrated CAN controller, Wi-Fi, Bluetooth, and considerable processing power on a single device, the ESP32 enables entirely new classes of applications that bridge traditional CAN networks with modern IoT infrastructure. Whether you are monitoring industrial equipment from across a factory floor or collecting vehicle diagnostics through a web browser, the ESP32 offers a remarkably capable and cost-effective platform.

This article explores practical ways to combine Wi-Fi and CAN Bus technology while highlighting the hardware capabilities that make such projects straightforward to implement.

Why Combine Wi-Fi with CAN Bus?

CAN Bus was designed for deterministic, reliable communication between electronic control units (ECUs). It was never intended to provide remote access or cloud connectivity.

Modern applications, however, increasingly demand:

• Remote diagnostics

• Wireless firmware updates

• Cloud-based data logging

• Mobile applications

• Browser-based configuration

• Predictive maintenance

• Fleet management

• Remote monitoring

Instead of replacing the CAN network, the ESP32 simply acts as an intelligent gateway between the wired CAN Bus and wireless communication.

This approach preserves the reliability of CAN while adding the flexibility of Wi-Fi and Bluetooth.

The ESP32 Advantage

Unlike many microcontrollers that require external networking hardware, the ESP32 integrates:

• Dual-core processor running up to 240 MHz

• Integrated Wi-Fi (802.11 b/g/n)

• Bluetooth Low Energy

• Large memory resources

• USB connectivity

• Extensive peripheral interfaces

• Native Classical CAN controller (TWAI)

This makes it possible to build sophisticated CAN gateways using a single inexpensive controller.

For developers already familiar with the Arduino IDE, getting started is remarkably straightforward.

Practical Application #1 – Wireless CAN Data Logger

One of the most common applications is a Wi-Fi-enabled CAN data logger.

Instead of connecting a USB cable to retrieve recorded traffic, the ESP32 can:

• Store CAN messages locally

• Upload log files automatically

• Serve data through an integrated web server

• Transfer recordings over Wi-Fi

• Stream live traffic to a remote PC

Maintenance personnel no longer need physical access to a machine. The logger can simply appear on the local network.

Practical Application #2 – Browser-Based Machine Dashboard

Imagine opening a browser and immediately viewing:

• Engine RPM

• Temperatures

• Hydraulic pressures

• Battery voltage

• Fuel consumption

• CAN Bus status

The ESP32 can host a lightweight web server that generates dashboards directly from live CAN messages.

No custom Windows application is required.

Any device with a browser—including tablets and smartphones—can become an operator display.

This approach is especially attractive for agricultural equipment, stationary generators, and industrial machines.

Practical Application #3 – Wireless ECU Diagnostics

Traditional diagnostics require a cable between the service computer and the vehicle.

An ESP32 gateway allows diagnostic software to communicate wirelessly with the network.

Typical examples include:

• Reading diagnostic messages

• Monitoring live sensor values

• Sending requests

• Performing service functions

• Recording intermittent failures

For development work, engineers gain significantly more flexibility because they are no longer tethered to the vehicle.

Practical Application #4 – Industrial IoT Gateway

Factories increasingly rely on centralized monitoring systems.

The ESP32 can collect information from CAN-connected controllers and publish selected parameters using standard IoT protocols.

Typical transmitted information includes:

• Machine status

• Production counters

• Alarm conditions

• Operating hours

• Energy consumption

• Temperature trends

Instead of replacing existing equipment, the ESP32 extends its capabilities by adding wireless connectivity.

Practical Application #5 – Mobile Apps for CAN Networks

Because the ESP32 supports Wi-Fi and Bluetooth, it can communicate directly with smartphones.

Applications include:

• Equipment configuration

• Vehicle status displays

• Remote control panels

• Maintenance applications

• Service menus

• Parameter adjustment

Rather than installing specialized software on a laptop, technicians can simply use a mobile device.

Practical Application #6 – Cloud Connectivity

One of the greatest strengths of the ESP32 is its ability to bridge CAN networks with cloud services.

Collected CAN data can be forwarded to cloud platforms for:

• Long-term storage

• Trend analysis

• Fleet management

• Predictive maintenance

• Remote alerts

• Statistical reporting

This is particularly valuable for agricultural machinery, commercial vehicles, industrial automation, and remote monitoring installations.

Practical Application #7 – CAN-to-Wi-Fi Development Tool

Engineers developing embedded software often need to observe CAN traffic while testing firmware.

An ESP32 can serve as a wireless CAN interface by:

• Capturing messages

• Filtering specific identifiers

• Streaming traffic over TCP/IP

• Supporting browser-based monitoring

• Forwarding selected frames to development software

This eliminates long USB cables and allows the test computer to remain safely outside harsh operating environments.

Classical CAN and CAN FD in One Platform

Many existing systems continue to use Classical CAN, while newer automotive and industrial applications increasingly adopt CAN FD.

Using hardware that supports both technologies provides a convenient migration path.

Copperhill Technologies' ESP32-S3 Board with CAN FD and Classical CAN Ports combines the ESP32-S3 microcontroller with both CAN interfaces on a single development platform. Classical CAN is handled by the ESP32-S3's native controller, while CAN FD communication is provided through a dedicated Microchip MCP2518FD controller. The board also includes integrated Wi-Fi, Bluetooth 5, native USB, generous Flash and PSRAM resources, an industrial-friendly 7–24 V power input, and high-speed CAN transceivers, making it suitable for everything from prototypes to production-oriented embedded applications.

For developers working on next-generation systems, this eliminates the need to choose between today's Classical CAN installations and tomorrow's CAN FD networks.

Typical Development Workflow

A typical ESP32 CAN gateway project often follows these steps:

1. Receive CAN messages from the network.

2. Decode the required parameters.

3. Process or filter the information.

4. Publish the data through Wi-Fi.

5. Display information on a web page, mobile app, or cloud service.

6. Accept commands remotely and transmit corresponding CAN messages back onto the network.

The entire gateway can be implemented on a compact embedded platform consuming only modest power.

Looking Ahead

As embedded systems continue to evolve, the line between traditional field buses and wireless networking continues to blur.

The ESP32 occupies a unique position by offering reliable CAN communication alongside modern wireless connectivity in a single, affordable device. For engineers developing industrial controllers, agricultural electronics, automotive diagnostics, marine systems, or IoT gateways, this combination dramatically reduces hardware complexity while opening opportunities that previously required multiple processors and dedicated networking hardware.

Whether your goal is a wireless data logger, a browser-based dashboard, a cloud-connected monitoring system, or a sophisticated CAN FD gateway, the ESP32 provides an excellent foundation. With development boards that support both Classical CAN and CAN FD, engineers can design solutions that remain compatible with existing equipment while preparing for the next generation of CAN-based networks.

Developing IoT Projects with ESP32: Unlock the full Potential of ESP32 in IoT development to create production-grade smart devices

From smart sensors and edge computing to cloud integration and TinyML, this comprehensive guide walks you through every stage of modern IoT development using the ESP32 and industry-standard tools, frameworks, and technologies.

Key Features

• Build complete IoT applications from the ground up with ESP32

• Connect devices securely to the cloud and visualize real-time data

• Develop practical projects including an audio player, smart home automation, voice-enabled devices, and TinyML applications

Book Description

The ESP32 has become one of the world's most popular microcontrollers for Internet of Things (IoT) applications, combining Wi-Fi, Bluetooth, impressive processing power, and low energy consumption in an affordable platform. Whether you're developing connected sensors, industrial controllers, or smart home devices, this book provides a complete roadmap for creating reliable, production-ready IoT systems.

Beginning with the fundamentals of IoT architecture and real-world design concepts, you'll build an ESP32-based application step by step. Along the way, you'll learn how to interface with sensors, manage peripherals, and integrate powerful libraries such as LittleFS and LVGL. You'll then connect your projects to Wi-Fi networks, implement industry-standard security features, exchange data with cloud platforms, and create professional dashboards using Grafana.

The book also explores emerging edge AI technologies by introducing TinyML on the ESP32-S3. Using the Edge Impulse platform, you'll learn how to develop, deploy, and run machine-learning models directly on embedded hardware, enabling intelligent devices that process data locally without relying on cloud computing.

With numerous hands-on examples and progressively more advanced projects, you'll steadily build practical skills throughout the book. The journey culminates in a complete Smart Home project that brings together embedded hardware, networking, cloud services, security, visualization, and edge AI into one integrated IoT solution.

If you're ready to move beyond simple ESP32 examples and build secure, scalable, and intelligent connected devices, this book will provide the knowledge and practical experience you need. More information...