A complete operating system for handheld devices based on ESP32 and FreeRTOS. This project implements a modular kernel architecture, a custom transactional file system, and advanced connectivity capabilities (AI Chat, UDP Mesh Messaging), all running on a low-cost, high-efficiency microcontroller.

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• True Multitasking Architecture: FreeRTOS-based kernel with segregated tasks for UI Rendering (50Hz), Input Sampling (High Speed), Network Communications, and Business Logic.

• Custom Flash File System: A Log-Structured File System designed from scratch featuring:

  • Automatic Wear Leveling and Garbage Collection to extend Flash memory life.
  • Power-loss corruption protection via Atomicity and Journaling.
  • Dynamic partitioning based on key prefixes.

• Modular Application Engine: Uses the Factory design pattern to dynamically load, unload, and manage the lifecycle of "Apps" to optimize RAM usage.

• Hybrid Connectivity:

  • Online Mode: REST Client for interaction with LLMs supporting stream responses.
  • Local Mode: Decentralized "Walkie-Talkie" style chat via UDP Broadcast over local network (Serverless).

• Smart Input: Experimental predictive text engine based on N-Grams to speed up typing.

• Power Management: Smart Deep Sleep with hardware interrupt wake-up and critical state persistence.

The system abandons the simple setup/loop paradigm in favor of a professional layered architecture:

graph TD
    H["Hardware (ESP32)"] --> D["Drivers (Pantalla, Teclado, Flash)"]
    D --> K[Kernel / CoreSystem]
    K --> OS[FreeRTOS Tasks]
    OS --> T1[Input Task]
    OS --> T2[UI Render Task]
    OS --> T3[Network/UDP Task]
    K --> AM[App Manager]
    AM --> App1[Calculator]
    AM --> App2[AI Chat]
    AM --> App3[Messaging]
    AM --> App4[Text Reader]

Acts as the central orchestrator (Singleton). It manages the application lifecycle, injects hardware dependencies, and controls the state machine transitions.

nstead of using standard file systems (SPIFFS/LittleFS), a direct driver over SPI Flash ( Flash.cpp / FlashInterface.cpp) was implemented to allow:

1. Append-Only Writing: Maximizes speed and flash lifespan.

2. Address Virtualization: Apps access data using keys ( MSG_ID, BOOK_TEXT) without knowing physical hex addresses.

3. Garbage Collection (GC): An intelligent background process compacts fragmented sectors when necessary, recovering space without losing active data.

• AI Chat: Client for language models (GPT/Claude/Local). Allows conversation with an AI, configuring parameters such as MODEL and CONTEXT directly in Flash.

2. Messaging (Local): Local instant messaging system. Devices on the same WiFi network automatically discover each other and exchange messages via UDP packets.

3. Text Reader: A book/document reader with smooth pagination, capable of reading large files stored in dedicated partitions.

4. Calculator: Mathematical utilities with a dedicated graphical interface.

5. Settings: Control panel for managing WiFi, brightness, and system parameters.

The system is designed to run on custom hardware.

• lib/APPS: Business logic for each application (Calculator, AI Chat, etc.).
• lib/BASICS: Low-level drivers (Flash, Battery, Screen, Keyboard).
• lib/APPS/CoreSystem: Kernel, State Machine, and Application Manager.
• src/main.cpp: FreeRTOS tasks and interrupts initialization.
• docs/: schematics and diagrams.

© 2025 Felix - Open Source Project.