ESP8266 WiFi Relay Controller

Overview

This project provides a versatile WiFi-controlled relay module for the ESP-01 using the ESP8266 microcontroller. The device offers remote relay control through a web interface, WebSocket, and optional Adafruit IO integration.

Features

• WiFi-enabled relay control
• Captive portal for easy device configuration
• Persistent device state storage
• Web-based user interface
• WebSocket real-time control
• Optional Adafruit IO cloud integration
• mDNS support for easy device discovery

Hardware Requirements

• ESP-01 module
• Relay module
• Power supply (3.3V recommended)

Pin Configuration

• RELAY_PIN: GPIO0 (Controls relay)
• LED_PIN: GPIO1 (Status indicator)

Setup and Configuration

Initial Setup

1. Power on the device
2. If no WiFi credentials are configured, the device will create a captive portal
3. Connect to ESP8266-Setup WiFi network (password: configme123)
4. Open http://192.168.4.1 in your web browser

Configuration Options

• WiFi SSID and Password
• Custom mDNS name (e.g., my-relay.local)
• Optional Adafruit IO integration
  • Adafruit IO Username
  • Adafruit IO Key
  • Relay Feed Name
  • IP Feed Name

Control Methods

Web Interface

• Access via http://[device-mdns-name].local
• Toggle relay on/off directly from the web page

WebSocket

• Real-time relay control
• Supports ON and OFF commands

Adafruit IO (Optional)

• Cloud-based control and monitoring
• Publish and subscribe to relay state
• Periodic IP address updates

Connectivity Features

• Automatic WiFi reconnection
• Configurable connection timeout
• Fallback to setup mode after multiple connection failures
• mDNS support for easy local network discovery

Configuration Storage

• Device settings stored in EEPROM
• Persistent relay state memory
• Supports default configuration if no valid config found

Debugging

• Serial output at 115200 baud
• Detailed logging for WiFi and Adafruit IO connections

Troubleshooting

• If WiFi connection fails, device enters captive portal mode
• Reset device or reconfigure WiFi credentials if needed

Dependencies

• ESP8266WiFi
• ESP8266WebServer
• ESP8266mDNS
• WebSocketsServer
• EEPROM
• DNSServer
• AdafruitIO_WiFi

Recommended Power Supply

• 3.3V, minimum 500mA
• Stable power source recommended for reliable operation

Flashing the Device

1. Use Arduino IDE or PlatformIO
2. Select "Generic ESP8266 Module"
3. Configure appropriate flash settings
4. Upload the firmware

Security Considerations

• Change default AP password
• Use strong WiFi credentials
• Consider using Adafruit IO's security features

License

MIT License

Contributing

Pull requests and issues are welcome. Please follow standard GitHub contribution guidelines.

Support

For issues or questions, please open a GitHub issue or contact the maintainer.