AQI Monitor
35
Air Quality Index
EXCELLENT
OLED Display
SmartAir v1.0
AQI: 35
Status: GOOD
CO2: 412ppm
Fan: OFF Rly: OFF
Up: 00:00:00
RGB LED Status
GREEN — GOOD
D3=0 D5=255 D6=0
🔄 Assembled View — Drag to Rotate · Scroll to Zoom
View Controls
Airflow Path
INTAKE
HEPA
CARBON
EXHAUST
Intake → MQ135 → HEPA Filter → Carbon Filter → Fan → Exhaust
Wiring Diagram
| Component | Pin | | Arduino |
|---|
| MQ135 | VCC | → | 5V |
| A0 | → | A0 |
| OLED | SDA | → | A4 |
| SCL | → | A5 |
| Relay | IN | → | D7 |
| RGB LED | R | → | D3(PWM) |
| G | → | D5(PWM) |
| B | → | D6(PWM) |
| Buzzer | + | → | D8 |
| Buck Conv. | 12V IN | → | Adapter |
| 5V OUT | → | Vin/GND |
Arduino Code (Live)
// Smart Air Purifier — Live Code
void loop() {
airQuality = analogRead(A0);
aqi = map(airQuality, 200, 800, 0, 500);
aqi = constrain(aqi, 0, 500);
// Relay / Fan control
if (aqi > 100) {
digitalWrite(RELAY_PIN, HIGH);
}
// Buzzer alert
if (aqi > 150) {
for(int i=0; i<3; i++) {
tone(BUZZER_PIN, 1000, 200);
delay(250);
}
}
updateLED();
updateDisplay();
delay(1000);
}