Meadow.Foundation.Sensors.Atmospheric.Sgp40 1.3.2.1-beta

Meadow.Foundation.Sensors.Atmospheric.Sgp40

SGP40 I2C VOC sensor driver

The Sgp40 library is designed for the Wilderness Labs Meadow .NET IoT platform and is part of Meadow.Foundation

The Meadow.Foundation peripherals library is an open-source repository of drivers and libraries that streamline and simplify adding hardware to your C# .NET Meadow IoT application.

For more information on developing for Meadow, visit developer.wildernesslabs.co, to view all Wilderness Labs open-source projects, including samples, visit github.com/wildernesslabs

Usage

Sgp40? sensor;

public override Task Initialize()
{
    Resolver.Log.Info("Initializing...");

    sensor = new Sgp40(Device.CreateI2cBus());

    Resolver.Log.Info($"Sensor SN: {sensor.SerialNumber:x6}");

    if (sensor.RunSelfTest())
    {
        Resolver.Log.Info("Self test successful");
    }
    else
    {
        Resolver.Log.Warn("Self test failed");
    }

    var consumer = Sgp40.CreateObserver(
        handler: result =>
        {
            Resolver.Log.Info($"Observer: VOC changed by threshold; new index: {result.New}");
        },
        filter: result =>
        {
            //c# 8 pattern match syntax. checks for !null and assigns var.
            return Math.Abs(result.New - result.Old ?? 0) > 10;
        }
    );
    sensor.Subscribe(consumer);

    sensor.Updated += (sender, result) =>
    {
        Resolver.Log.Info($"  VOC: {result.New}");
    };

    return base.Initialize();
}

public override async Task Run()
{
    await ReadConditions();

    sensor?.StartUpdating(TimeSpan.FromSeconds(1));
}

async Task ReadConditions()
{
    if (sensor == null) { return; }

    var result = await sensor.Read();
    Resolver.Log.Info("Initial Readings:");
    Resolver.Log.Info($"  Temperature: {result}");
}