A comprehensive RFID sensor system built for ESP8266 microcontrollers, featuring LED control, RFID card detection, serial communication via Protocol Buffers, and over-the-air (OTA) update capabilities.

Features
Hardware Requirements
Software Requirements
Installation
Configuration
Building and Uploading
Usage
API/Message Protocol
OTA Updates
Development
Contributing
License

Features

RFID Detection: Reads RFID cards/tags using MFRC522 module
LED Control: Advanced LED animations including static, pulse, fade, and flicker effects
Serial Communication: Protocol Buffer-based messaging system for reliable data exchange
OTA Updates: Over-the-air firmware updates for remote maintenance
Modular Architecture: Clean separation of hardware components (LED, RFID, Serial)
Configurable: Extensive configuration options via protobuf messages
ESP8266 Compatible: Optimized for ESP8266 microcontrollers

Hardware Requirements

Microcontroller: ESP8266 (ESP-12E module recommended)
RFID Reader: MFRC522 RFID/NFC module
LED Strip: WS2812B or compatible addressable LED strip (NeoPixel)
Power Supply: 3.3V-5V DC power supply (depending on LED strip requirements)
Connections:
- RFID SS pin → GPIO4 (D2)
- RFID RST pin → GPIO5 (D1)
- LED data pin → GPIO2 (D4)
- Serial communication via USB/UART

Software Requirements

PlatformIO: For project management and building
Arduino Framework: ESP8266 core
Dependencies:
- MFRC522 (RFID library)
- FastLED (LED control library)
- Nanopb (Protocol Buffers for embedded systems)

Installation

Clone the repository:

git clone <repository-url>
cd RFID-SENSOR-GEN2

Install PlatformIO (if not already installed):
```
pip install platformio
```
Install dependencies:
```
pio pkg install
```

Configuration

PlatformIO Configuration

The project uses platformio.ini for configuration. Key settings:

[platformio]
default_envs = esp8285

[env]
framework = arduino
monitor_speed = 9600
board_build.filesystem = littlefs

[env:esp8285]
platform = espressif8266
board = esp12e

[env:esp8285-ota]
platform = espressif8266
board = esp12e
upload_protocol = espota
upload_port = 192.168.20.41

Hardware Pin Configuration

Modify pin assignments in src/main.cpp:

// LED pin (default: GPIO2)
HardwareLed<2> led;

// RFID pins (SS=D2/GPIO4, RST=D1/GPIO5)
HardwareRfid rfid(4, 5);

Building and Uploading

Standard Upload (USB)

Connect ESP8266 to computer via USB
Build and upload:
```
pio run -t upload
```

OTA Upload

Ensure device is connected to network
Use OTA environment:
```
pio run -e esp8285-ota -t upload
```

Monitor Serial Output

pio device monitor

Usage

Basic Operation

The device continuously monitors for RFID cards and controls LED animations based on received commands. It communicates with a control system via serial interface using Protocol Buffer messages.

LED Control

The system supports multiple LED animation types:

Static: Solid color display
Pulse: Breathing effect with configurable speed
Fade: Smooth color transitions
Flicker: Random intensity variations

RFID Detection

When an RFID card is detected, the system:

Reads the card ID
Sends a SensorToControlMessage with RFID reading
Can trigger LED animations based on configuration

API/Message Protocol

The system uses Protocol Buffers for all communication. Messages are defined in proto/hardware.proto.

Message Types

Sensor to Control Messages

message SensorToControlMessage {
    uint32 sensor_id = 1;
    oneof payload {
        RfidReading rfid_reading = 2;
        SensorOTAEnableResponse ota_response = 3;
    }
}

Control to Sensor Messages

message ControlToSensorMessage {
    uint32 control_id = 1;
    oneof payload {
        LedConfig led_config = 2;
        SensorOTAEnable ota_enable = 3;
        SensorRestart restart = 4;
    }
}

LED Configuration

message LedConfig {
    uint32 brightness = 1; // 0-255
    uint32 duration_ms = 2; // 0 for indefinite

    oneof animation_params {
        StaticParams static_params = 3;
        PulseParams pulse_params = 4;
        FadeParams fade_params = 5;
        FlickerParams flicker_params = 6;
    }
}

Example Usage

Send LED configuration via serial:

// Create LED config message
hardware_ControlToSensorMessage msg = {0};
msg.control_id = 1;
msg.which_payload = hardware_ControlToSensorMessage_led_config_tag;

// Configure static green LED
msg.payload.led_config.brightness = 128;
msg.payload.led_config.which_animation_params = hardware_LedConfig_static_params_tag;
msg.payload.led_config.animation_params.static_params.color = 0x00FF00;

// Send via serial
serial.sendMessage(msg);

OTA Updates

Enabling OTA

Send an OTA enable message:

message SensorOTAEnable {
    string ssid = 1;
    string password = 2;
    uint32 timeout_seconds = 3;
    bool as_station_mode = 4;
    bool use_static_ip = 5;
    string static_ip = 6;
    string netmask = 7;
    string gateway = 8;
}

OTA Response

The device responds with:

message SensorOTAEnableResponse {
    bool success = 1;
    string ip_address = 2;
    string error_message = 3;
}

Performing OTA Update

Enable OTA mode on device
Use PlatformIO OTA environment:
```
pio run -e esp8285-ota -t upload
```

Development

Project Structure

RFID-SENSOR-GEN2/
├── lib/
│   ├── hardware/
│   │   ├── hardware_led.cpp/hpp    # LED control
│   │   ├── hardware_rfid.cpp/hpp   # RFID reading
│   │   ├── hardware_serial.cpp/hpp # Serial communication
│   │   └── library.json
│   └── ota/
│       ├── ota_update.cpp/hpp      # OTA functionality
│       └── library.json
├── proto/
│   ├── hardware.proto              # Protocol definitions
│   └── hardware.options            # Nanopb options
├── src/
│   └── main.cpp                    # Main application
├── test/                           # Unit tests
├── platformio.ini                  # PlatformIO config
└── README.md                       # This file

Adding New Features

Hardware Components: Add new classes in lib/hardware/
Message Types: Extend proto/hardware.proto
Regenerate Protobuf: Run pio run -t build to regenerate C++ files
Integration: Update src/main.cpp to include new components

Testing

Run unit tests:

pio test

Debugging

Use Serial.println() for debug output
Monitor via pio device monitor
Check LED patterns for status indication

Contributing

Fork the repository
Create a feature branch: git checkout -b feature-name
Make your changes
Add tests if applicable
Run tests: pio test
Commit changes: git commit -am 'Add feature'
Push to branch: git push origin feature-name
Submit a pull request

Code Style

Use consistent naming conventions
Add Doxygen-style comments for classes and methods
Follow Arduino coding standards
Keep functions focused and modular

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

For questions, issues, or contributions:

Create an issue on GitHub
Check the PlatformIO documentation
Review ESP8266 Arduino documentation

Version History

v1.0.0: Initial release with basic RFID detection, LED control, and OTA support
Future versions: Enhanced animations, additional sensors, improved error handling

Built with ❤️ using PlatformIO and ESP8266

README.md

RFID-SENSOR-GEN2

Table of Contents