An All-in-One Platform for Automotive Electronics Projects

Modern cars are packed with electronics, but manufacturers don't exactly make them easy to modify. Whether you're trying to add Bluetooth audio to a classic car, reverse engineer a vehicle's communication systems, or automate an accessory, you'll probably need more than a typical development board to get the job done. That's where Ermine, a new extensible electronics platform from St11 Digital, comes in. It combines several automotive communication interfaces, programmable I/O, and expansion capabilities in a compact, rugged package.

Ermine grew out of a couple of automotive projects that needed specialized hardware. The developers wanted to replace the original phone system in a 1990s Jaguar and emulate a CD changer in an early 2000s Volvo. Neither project had a convenient off-the-shelf solution, especially one small and reliable enough to leave permanently installed in a vehicle. Rather than build separate boards for each application, they decided to create a more versatile platform that could handle both projects and plenty more.

At the core of Ermine is an ESP32 microcontroller with 4 MB of flash memory, Wi-Fi, and Bluetooth connectivity. What makes the board particularly interesting, however, is its collection of built-in interfaces. CAN, ISO9141 K-line, LIN, and RS-485 are all supported, allowing Ermine to communicate with a wide variety of automotive electronics and industrial equipment. There's also general-purpose digital I/O, a microSD card slot, and a 25-pin D-sub connector for external connections.

Two versions are planned: the Ermine XK, which has one expansion slot and four high-side MOSFET switches for controlling electrical loads, and the Ermine DX, which offers two expansion slots. Optional modules further extend the platform's capabilities. An audio module adds a stereo DAC and microphone preamplifier for projects like CD changer emulators and hands-free phone systems, while a GNSS module provides satellite positioning and a three-axis gyroscope. Another module adds four general-purpose I/O connections.

Ermine is designed for permanent installation as well as experimentation. Its anodized aluminum enclosure measures just 95×63×25 mm, and the board can operate from either a 5 V supply or a 10 V to 28 V input. Built-in voltage and current monitoring provide additional information about the power supply.

On the software side, Ermine ships with an enhanced version of MicroPython, so there's no need to develop everything from scratch. The self-hosted Ermine Dash application provides a browser-based interface for programming, file management, interactive terminal access, and data logging.

St11 Digital plans to make the platform open source, including hardware schematics, expansion module documentation, firmware, and software tools. These resources are expected to become available when Ermine enters production.

For anyone who enjoys tinkering with automotive electronics, Ermine could eliminate a lot of the wiring and custom hardware development that usually comes with these projects. Its versatility also makes it a promising option for industrial automation and other applications beyond the garage. St11 Digital hasn't announced a launch date or pricing yet, but interested developers can sign up to receive notifications when the crowdfunding campaign goes live.