W5500 Ethernet-Powered Race Car Telemetry Dashboard

Real-Time Vehicle Telemetry System with Teensy 4.1 and CrowPanel ESP32-S3

Introduction

racecar-35 is a real-time telemetry and digital dashboard project designed for track and motorsport vehicles. Rather than acting as a simple speedometer, the system collects and visualizes live vehicle data such as RPM, GPS, IMU, oil pressure, and coolant temperature in real time.

The project uses a dual-MCU architecture.
A Teensy 4.1 serves as the telemetry controller responsible for sensor processing, SD card logging, and Ethernet networking, while a CrowPanel ESP32-S3 7-inch display handles the driver-facing dashboard UI. The two systems communicate through a UART telemetry stream, separating real-time sensor processing from graphics rendering.

One of the most interesting aspects of the project is the use of the WIZnet W5500 Ethernet controller to provide a stable telemetry backhaul combined with SD card logging and an offline-first upload architecture suitable for motorsport and industrial telemetry environments.

System Architecture

The core design concept is the separation of real-time telemetry processing and UI rendering. Teensy 4.1 handles deterministic sensor tasks, while the ESP32-S3 focuses entirely on graphics rendering and touch interaction. This architecture improves stability and maintainability in demanding vehicle environments.

Hardware Features

Teensy 4.1 Telemetry Unit

The Teensy 4.1 acts as the central telemetry controller.

Main responsibilities:

• GNSS data acquisition
• RPM interrupt processing
• Oil and coolant sensor ADC processing
• MPU6050 IMU sampling
• SD card session logging
• W5500 Ethernet networking

Because Teensy 4.1 is optimized for high-speed real-time processing, it is well suited for telemetry applications requiring stable sensor timing and deterministic behavior.

CrowPanel ESP32-S3 Dashboard

The CrowPanel ESP32-S3 provides the driver-facing interface.

Displayed telemetry includes:

• Vehicle speed
• RPM bar
• GPS status
• Oil pressure
• Coolant temperature
• Recording status

The touch UI also provides:

• Track selection
• Logging control
• System settings

This separation allows the dashboard to remain responsive without affecting telemetry acquisition performance.

PVT (Position Velocity Time) Navigation

The system uses u-blox GNSS PVT (Position Velocity Time) navigation data.

Unlike traditional GPS parsing methods, PVT provides:

• Position
• Vehicle speed
• Heading
• GPS time
• Satellite count
• GPS fix status

within a single navigation packet.

This makes the system suitable not only for dashboard visualization but also for advanced telemetry applications such as:

• Lap timing
• Racing line analysis
• Heading analysis
• Trajectory logging

ASCII CSV Telemetry Protocol

Telemetry data is streamed from the Teensy to the CrowPanel using a human-readable ASCII CSV protocol.

Example:

GPS,3,12,37.5665,126.9780,82.3,184.5
ENG,4520,620,1880
IMU,0.12,-0.03,1.02,0.5,-1.1,0.0

• Easy UART debugging
• Loose coupling between MCUs
• Simple sensor expansion
• Improved maintainability

Instead of relying on complex binary protocols, the project intentionally uses readable telemetry streams to simplify development and troubleshooting.

LovyanGFX-Based Dashboard Rendering

The CrowPanel dashboard uses LovyanGFX, a high-performance graphics library for ESP32 platforms.

LovyanGFX provides:

• DMA-based rendering
• Sprite buffering
• Flicker-free graphics
• Large RGB LCD support

This is especially important for automotive dashboards where RPM and speed values are constantly changing. By rendering frames in memory before updating the display, LovyanGFX enables smooth, automotive-style dashboard animations without visible flickering.

Why W5500 Ethernet?

In this project, the W5500 is more than just an Ethernet interface. It acts as a reliable telemetry networking infrastructure for the vehicle system.

In motorsport and industrial telemetry environments, Wi-Fi may suffer from:

• Interference
• Unstable connectivity
• Outdoor communication limitations

The W5500 provides:

• Reliable TCP/IP networking
• Low latency
• Deterministic communication
• Stable wired connectivity

making it highly suitable for telemetry data upload and synchronization tasks.

W5500 Ethernet Features

The W5500 connected to the Teensy 4.1 handles:

• DHCP-based IP assignment
• NTP time synchronization
• HTTP telemetry upload
• Queue-based retry handling
• Ethernet diagnostics

The project also implements an offline-first architecture.
If the network connection is unavailable, telemetry data is first stored on the SD card and later uploaded automatically when Ethernet connectivity is restored.

This approach is highly valuable for real-world telemetry and industrial logging systems where uninterrupted networking cannot always be guaranteed.

Application Possibilities

Although designed for motorsport telemetry, the architecture can be extended to many other applications.

Possible use cases include:

• Motorsport telemetry systems
• Industrial vehicle monitoring
• Fleet management
• Heavy equipment dashboards
• Outdoor telemetry systems
• Edge data loggers

The combination of real-time telemetry processing and reliable W5500 Ethernet networking makes the design particularly suitable for industrial and embedded telemetry applications.

Conclusion

racecar-35 demonstrates how Teensy 4.1, ESP32-S3, and W5500 Ethernet can be combined to create a powerful real-time vehicle telemetry platform.

By integrating u-blox PVT navigation, ASCII telemetry streaming, LovyanGFX dashboard rendering, and reliable W5500 Ethernet networking, the project showcases a practical architecture for motorsport and industrial telemetry systems.

Most importantly, the W5500 serves not simply as an Internet connectivity device, but as a stable telemetry backhaul that enhances system reliability and enables robust real-time embedded networking in demanding environments.