ehRadio

Introduction

ehRadio is an advanced internet radio firmware designed to run on the ESP32 ecosystem. While it supports standard ESP32 and ESP32-C3 boards, it is optimized for the ESP32-S3 to take advantage of improved peripherals and processing power. The project allows builders to create a fully functional radio using an ESP32, an audio decoder (such as I2S PCM or VS1053), a display, and various input methods. For certain integrated boards like the ES3C28P, the firmware can run with almost no additional peripherals.

Developed primarily using VS Code and PlatformIO, ehRadio is a fork of the well-known ёRadio (yoRadio) project. It aims to bridge the gap between complex DIY builds and user-friendly consumer devices by providing a web-based flasher and OTA updates, making the firmware accessible even to those who prefer not to dive deep into IDEs.

Features and Capabilities

ehRadio focuses on increasing usability for end-users while maintaining deep customizability for hardware builders. It inherits a robust control architecture supporting up to two rotary encoders, six buttons, touchscreens, and IR remotes.

User Experience

The user interface has been significantly overhauled from its predecessor. It features a mobile-first WebUI available in 50 languages, supporting playlist editing, importing, and merging. Integration with the Radio-browser API allows for easy station searching, and a curated list feature enables users to preview and download playlists. For smart home enthusiasts, the firmware offers improved Home Assistant integration via MQTT, alongside Telnet and HTTP control options.

Builder Flexibility

For hardware builders, the project moves the focus toward the ESP32-S3, recommending 8MB of flash to support all features. It offers extensive support for various audio decoders:

• I2S PCM decoders and VS1053/VS1003 (updated for high bitrate streams).
• ES8311 codecs common on modern S3 display boards.
• Custom SPI bus pin assignments, allowing displays and audio decoders to share or separate buses (Bus A and Bus B) more flexibly than standard implementations.

Interface and Control

The WebUI is a centerpiece of the project, optimized for mobile browsers to provide a seamless remote control experience. Beyond the web interface, the system supports physical interaction through various hardware peripherals. Almost all system and user default settings are configurable via a myoptions.h file, which can be generated using a dedicated web-based tool provided by the project.

Technical Architecture and Libraries

The codebase relies on specialized audio handling, currently utilizing the ESP32-audioI2S and ESP32-vs1053_ext libraries. These are tightly integrated to ensure stable playback of internet streams. The project also incorporates a custom command handler, unified error logging, and an optimized RTOS background task for the playback queue to ensure smooth performance even during heavy network activity.

Hardware Implementation

Real-world builds often utilize repurposed hardware, such as gutting cheap Bluetooth speakers and fitting them with ESP32-S3 internals. Reliability is emphasized through the use of XH2.54 connectors rather than breadboards or DuPont wires, ensuring stable connections within portable enclosures.

A History of ESP Radios

The project is part of a long lineage of ESP-based audio projects. It traces its roots back to Edzelf’s original Esp-radio from 2016, through Ka-Radio, and eventually to ёRadio. ehRadio represents a modern evolution of these efforts, focusing on the latest ESP32-S3 hardware and modern web standards while maintaining compatibility with the vast ecosystem of DIY radio hardware developed over the last decade.