Air quality monitor

Connected Particle matter, eCO2 & TVOC air quality monitor.

Features:

• Particle matter monitoring (PM1, PM12.5, PM4, PM10)
• eCO2 / TVOC monitoring
• MQTT connectivity

Todo

• Store sgp sensor baseline in esp32 memory & restore it on boot.

Parts

• LILYGO® TTGO T-Display ESP32
• Particulate Matter Sensor SPS30
• SGP30 Air Quality Sensor

Wiring

Both SPS & SGP sensor are connected to the I2C bus (pin 21 & 22)

Build

Dependencies

• Button2
• TFT_eSPI
• PubSubClient
• WiFiClientSecure
• Adafruit_SGP30
• arduino-sps

Configuration

Display:
The TFT_eSPI needs to be configured for TTGo board / screen. Edit the <your-TFT_eSPI-library-path>/User_Setup_Select.h:

//#include <User_Setup.h>
#include <User_Setups/Setup25_TTGO_T_Display.h>

Connectivity:
Edit the configuration section of the main.ino file according to your needs:

// Configuration
char* wifiSsid = "your-ssid";
char* wifiPassword = "your-wifi-password";
char* mqttServer = "your-mqtt.server";
char* mqttUser = "your-mqtt-user";
char* mqttPassword = "your-mqtt-password";

Compiler:
Make sure to include the repository directory to your compiler include path. Example for vscode:

// .vscode/c_cpp_properties.json (inside the source directory)
"configurations": [
        {
            "includePath": [
                ...
                "${workspaceFolder}",
            ],
            ...
        }
    ],
    ...
}

References

• https://github.com/Bodmer/TFT_eSPI/tree/master/examples
• https://github.com/Xinyuan-LilyGO/TTGO-T-Display
• https://cdn.sparkfun.com/assets/2/d/2/a/6/Sensirion_SPS30_Particulate_Matter_Sensor_v0.9_D1__1_.pdf
• https://forum.airnowtech.org/t/the-aqi-equation/169
• https://www.epa.gov/sites/production/files/2014-05/documents/zell-aqi.pdf
• https://forum.airnowtech.org/t/aqi-calculations-overview-ozone-pm2-5-and-pm10/168