Arduino Nano Matter AQI

This project runs on Arduino Nano Matter and measures indoor air quality using:

• ENS160 → eCO₂ and tVOC
• BME680 → Humidity & Pressure (gas sensing disabled)
• DS18B20 → Temperature
• OLED (128×64 SSD1306) for local display
• RGB LED (or fallback single LED) for air quality alerts
• Matter protocol for HomeKit / Matter integration

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Features

• OLED Display
  • Shows AQI (1–5 with label), eCO₂, tVOC, Humidity, Pressure, Temperature
• LED Alerts (simplified)
  • tVOC out of safe range → Purple
  • eCO₂ out of safe range → Blue
  • Both out of safe range → Red
  • Constant light, no blinking
• Safe Ranges
  • eCO₂: ≤ 1000 ppm
  • tVOC: ≤ 500 ppb
  • Humidity: 30–70 %
  • Temperature: 18–25 °C
  • Pressure: 950–1050 hPa
• Matter Integration
  • Publishes: Temperature, Humidity, Pressure
  • Optional: Air Quality index (enum for HomeKit)
• Pairing Screen
  • QR code and manual code shown on OLED for quick onboarding

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License

This project is licensed under the MIT License – free to use, modify, and distribute.

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Hardware Setup

• Arduino Nano Matter
• ENS160 sensor (I²C, addr 0x53)
• BME680 sensor (I²C, addr 0x76/0x77)
• DS18B20 sensor (1-Wire, pin D5)
• SSD1306 OLED 128×64 (I²C, addr 0x3C)
• RGB LED (active HIGH) or onboard LED

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Screenshots

OLED Sensor Display

Shows live AQI, eCO₂, tVOC, Humidity, Pressure, Temperature.

OLED Pairing Screen

Shows Matter QR code + manual pairing code, with Thread status.

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Notes

• At the moment, iOS / HomeKit only exposes Temperature, Humidity, and Pressure over Matter.
• Air Quality (enum tile) is experimental and optional.
• LED indication is simplified to avoid night-time blinking and distraction.

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