Air Quality Monitor

🚀 Features

• Dual-Sensor Monitoring:
  
  CO₂, Temperature, and Humidity: via Sensirion SCD30 (NDIR technology for laboratory-grade precision).
  
  Particulate Matter (PM1.0, PM2.5, PM10): via Plantower PMS5003 (Laser scattering).
• Advanced Display UI (ST7735):
  
  Real-time CO₂ Graph: 30-minute visual history with auto-scaling.
  
  Persistent Clock: Smart RTC logic that continues to show time even if Wi-Fi connection is lost (after initial sync).
  
  Uptime Tracker: Automatically switches to system uptime if NTP time is not yet available.
  
  Smooth Progress Bar: Visual refresh-rate indicator for data updates.
  
  System Diagnostics: Detailed splash screen showing sensor and network status on boot.
• Smart Connectivity & Logic:
  
  Multi-WiFi Support: Remembers up to 5 networks and connects to the strongest available.
  
  Automatic AP Mode: Enters Access Point mode (192.168.4.1) for configuration if no saved Wi-Fi is found.
  
  MQTT Integration: Pro-level data streaming to Home Assistant, OpenHAB, or Node-RED in JSON format with status indicators (M:OK/M:ERR).
• Web-Based Settings Manager (V1.12):
  
  On-the-fly Config: Change Wi-Fi credentials, MQTT broker details, GMT offset, and DST (Daylight Saving Time) directly from your browser.
  
  Network Scanner: Built-in WiFi scanner in the web interface for easy setup.
• Reliability:
  
  Non-Volatile Memory: All settings are securely saved in ESP32 Flash (Preferences).
  
  Internal RTC Persistence: Enhanced time-keeping stability without constant internet polling.

📊 Interpretation Levels

The device uses universal color-coding for both the Web UI and the TFT Display:

⚙️ Configuration & Setup

• Upload:
  Download the AirMonitor_v2.0 directory.
  Open AirMonitor_v2.0.ino in your Arduino IDE.
  Note: Ensure all project files (.ino, .h, .cpp) remain in this folder for the project to compile correctly.
  Select ESP32-S3 Dev Module and flash the sketch to your device.
  
• First Boot:
  The device will create a temporary Wi-Fi network: AIR-SCAN-CONFIG (Password: 12345678).
  
• Web Portal:
  Connect your phone or PC to this network and navigate to http://192.168.4.1 in your browser.
  
• Settings:
  Scan for your local Wi-Fi network and enter the credentials.
  Enter your MQTT Broker details (optional).
  Click Save & Restart.
  
• Operation:
  After rebooting, the device will display its new local IP address on the screen.
  Enter this IP in your browser to access the real-time monitoring dashboard.
  

📡 MQTT Payload Format

The device publishes a JSON string to the topic air/status every 10 seconds:

{
  "co2": 650,
  "pm1": 5,
  "pm25": 12,
  "pm10": 15,
  "t": 24.5,
  "h": 45
}