Open Source Embedded Projects

A real-time audio frequency visualizer built on the ESP32 microcontroller using the Arduino framework and Kiss FFT library. It processes audio signals through ADC or I2S inputs to display 64 frequency bands on an SSD1322 OLED screen.

A game selection menu and emulator frontend for running single-screen Game & Watch ROMs on the M5Stack Tab5. It features support for touch controls, USB gamepads, and automatic screen orientation via the built-in IMU.

A Rust-based firmware project for the Solum EL029H4WRC electronic shelf label featuring the nRF52811 SoC. It enables custom code execution on the tag, including e-paper display control for text and images using the embedded-graphics ecosystem. The project demonstrates how to use a Raspberry Pi Pico as a debug probe for flashing and debugging via SWD.

An nRF52840-based Zigbee sensor designed to monitor flow and return temperatures in heating systems using dual NTC thermistor probes. Built with the nRF Connect SDK and Zephyr RTOS, it is optimized for ultra-low power consumption, achieving over a year of battery life on a coin cell.

An ESP32-S3 based portable intelligent electronic load featuring high-precision control and a rich graphical interface. It utilizes FreeRTOS for multi-tasking and integrates PID and Model Predictive Control (MPC) algorithms with Kalman filtering for accurate current regulation. The system supports Constant Current (CC), Constant Power (CP), and Constant Resistance (CR) modes with real-time monitoring via LVGL.

A sophisticated multi-mode audio system built by upcycling a 1978 Sony FX-300 chassis. It utilizes a distributed architecture with a Teensy 4.0 for main control, an ESP32 for Bluetooth A2DP, and an Arduino Nano for peripheral management, supporting FM radio, SD playback, and NFC-triggered automation.

A portable real-time aircraft tracker for the M5StickC Plus 2 that utilizes the adsb.lol API to display flight telemetry and route information. It features a multi-page OLED interface, emergency squawk highlighting, and a web-based setup portal for easy configuration.

A high-performance library for RP2040 and RP2350 microcontrollers that implements 100 MBit/s Fast Ethernet transmission using the PIO peripheral. It achieves throughput of approximately 11 MByte/s by offloading MLT-3 encoding, 4B5B line coding, and scrambling to hardware-assisted lookups and DMA.

A 4-voice polyphonic synthesizer designed for the Raspberry Pi Pico 2 and RP2350 microcontroller. It features built-in chorus and delay effects, MIDI control via USB or UART, and support for high-quality I2S DACs or PWM audio output.

A Model Context Protocol (MCP) server implementation for the ESP32-CAM that enables remote camera control and system monitoring through a standardized JSON-RPC 2.0 API. It supports image capture optimized for AI assistants, LED/flash management, and comprehensive hardware diagnostics.

A comprehensive treadmill computer replacement based on the ESP32-S3 and ESPHome firmware. It implements the Fitness Machine Service (FTMS) protocol to enable direct Bluetooth connectivity with fitness apps like Zwift and Kinomap while controlling treadmill hardware via UART.

A firmware project for an STM32L071-based USB dongle that enables LoRa communication via AT commands. It utilizes the Semtech SX1262 transceiver and FreeRTOS to provide a plug-and-play wireless link for testing, range measurement, and sensor networks.

A modular, high-performance weather display system for the LilyGO T-Display S3 powered by an ESP32-S3. It provides real-time weather updates via the OpenWeatherMap API, featuring a smooth 40 FPS UI, automatic NTP time synchronization, and robust error recovery.

A tiny, wireless co-processor and debugger for ARM microcontrollers based on the ESP32-C3. It enables remote telemetry, live re-programming, and wireless debugging via SWD using the Rust Embassy framework.

A technical implementation and hardware guide for the ESP32-C3 Supermini board equipped with a 0.42-inch OLED. It provides a specific software workaround for the U8g2 library to support the non-standard 72x40 resolution using coordinate offsets. The project includes pin mappings and an Arduino-based example for I2C display communication.

Open-source hardware design for a color e-Paper photo frame utilizing the Spectra 6 EInk display technology. The repository provides PCB source files, 3D-printable mechanical components, and laser-cutting templates for a complete embedded display assembly.

An ESPHome component designed to interface with Hitachi air conditioners using the serial H-Link protocol. It serves as a local, open-source alternative to proprietary cloud adapters, providing full integration with Home Assistant. The project supports a wide range of features including climate control, outdoor temperature sensing, and maintenance alerts on ESP32 and LibreTiny hardware.

A standalone ESP32-based voice assistant that enables natural conversations with multiple custom AI personalities. It integrates ElevenLabs for speech-to-text, GroqCloud or OpenAI for LLM processing, and OpenAI for text-to-speech, supporting real-time web searches and email archiving of chat history.

A collection of ESPHome configuration files and external components specifically designed for M5Stack hardware. It provides ready-to-use YAML templates for devices like the CoreS3, Atom EchoS3R, and PowerHub, utilizing the ESP-IDF framework for Home Assistant integration.

A hardware modification project that replaces the WWVB radio receiver in an atomic clock with an ESP8266 module. It synchronizes time via the Network Time Protocol (NTP) and generates a digital signal mimicking the WWVB format to update the clock's original controller.

A dedicated hardware controller for Eight Sleep mattresses using the M5Stack ATOMS3 Dev Kit and ESPHome. It provides a physical interface to monitor bed temperature, sleep stages, and state, while allowing users to cycle through temperature presets via a built-in button and Home Assistant integration.

A dual-processor flight control system based on the STM32H753VI microcontroller, designed for UAVs, drones, and hobby rockets. It features a dedicated co-processor for sensor fusion and supports advanced protocols including DShot, SBUS, and CRSF.

An ESP32-C3 based HDMI multiplexer that enables wireless switching between two HDMI sources. It utilizes the TS3DV642 high-speed switch IC to support HDMI 2.0 specifications, including 4K resolution at 60Hz.

A custom firmware project for a home-built radio receiver based on the ESP32-S2 and SI4732 module. It features a high-resolution Sharp LS027B7DH01 LCD and utilizes the Arduino framework with libraries like U8g2 and PU2CLR SI4735 for multi-band radio reception.

An ESP32-based hardware wallet for the M5Stack Cardputer that enables seed generation, address management, and transaction signing. It supports BIP39 standards, BIP84 Native SegWit addresses, and secure seed storage using RFID tags or SD cards.

Buttfinity is a modular, customizable button and control system designed for the Gridfinity ecosystem. It utilizes ESP32, ESP8266, and RP2040 microcontrollers to provide functionality as a BLE keyboard, Home Assistant interface, or MIDI controller.

An ESP32-based application that displays daily C++ quiz questions on a 7.5-inch E-Ink screen. It utilizes a Google Sheets backend with Apps Script for content delivery and implements deep sleep for extended battery life.

Chronos Watchy is an alternative firmware for the Watchy e-ink smartwatch, built using the LVGL graphics library and the Arduino framework for ESP32. It enables advanced features like turn-by-turn navigation, smartphone notifications, and activity tracking through integration with the Chronos companion app.

A foundational starter application for the MXChip AZ3166 IoT DevKit based on the Eclipse ThreadX RTOS and NetX Duo network stack. It provides a preconfigured environment for the STM32F412RG MCU, enabling WiFi connectivity and peripheral access for embedded IoT development.

A firmware project for ESP32-S3 that acts as a USB-to-BLE HID bridge, allowing Bluetooth controllers like the Xbox Wireless Controller to be used with the Nintendo Switch. It utilizes ESP-IDF, FreeRTOS, and the TinyUSB stack to emulate a Nintendo Switch Pro Controller over USB while acting as a BLE GATT client.

An advanced internet radio streamer built on the ESP32-S3 platform, featuring support for MP3, AAC, VORBIS, and FLAC streams. It integrates a web server for remote control, an OLED display for visualization, and supports both rotary encoder and infrared remote inputs.

A custom ESP8266 firmware for Geek Magic smart clock clones featuring NTP synchronization, Pomodoro timers, and a web-based configuration dashboard. It utilizes the TFT_eSPI library for display management and LittleFS for asset storage. The project also includes a Linux-based companion server for forwarding system notifications to the device display.

A Wi-Fi-enabled pixel art player built on the ESP32-P4 platform featuring multi-buffer rendering for gapless playback of animated WebP, GIF, and PNG files. It integrates with the Makapix Club social network via secure MQTTS and provides a local web interface for device management.

A high-performance wavetable synthesizer firmware for the ESP32-S3 that enables high-quality SoundFont 2 (SF2) playback. It leverages PSRAM for sample loading and supports USB MIDI, external I2S DACs, and runtime switching between LittleFS and SD card storage.

A Rust-embedded firmware for the SparkFun ProMicro RP2040 that implements a variant of the Chordite chorded keyboard. It leverages the Embassy async framework to provide HID keyboard and mouse functionality with support for IMU-based motion sensing and LCD displays.

An end-to-end conversational AI assistant using an ESP32 for real-time audio capture and playback. It leverages a Python backend for Speech-to-Text (Whisper), Language Modeling (Gemini), and Text-to-Speech (Piper) via WebSocket streaming. The system targets ESP32 hardware with I2S peripherals for high-quality voice interaction.