Meadow.Foundation.Sensors.Environmental.Scd40

Scd40
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

Code Example

Scd40 sensor;

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

    var i2cBus = Device.CreateI2cBus(Meadow.Hardware.I2cBusSpeed.Standard);

    sensor = new Scd40(i2cBus);
    var serialNum = sensor.GetSerialNumber();
    Resolver.Log.Info($"Serial: {BitConverter.ToString(serialNum)}");

    var consumer = Scd40.CreateObserver(
        handler: result =>
        {
            Resolver.Log.Info($"Observer: Temp changed by threshold; new temp: {result.New.Temperature?.Celsius:N2}C, old: {result.Old?.Temperature?.Celsius:N2}C");
        },
        filter: result =>
        {
            if (result.Old?.Temperature is { } oldTemp &&
                result.Old?.Humidity is { } oldHumidity &&
                result.New.Temperature is { } newTemp &&
                result.New.Humidity is { } newHumidity)
            {
                return ((newTemp - oldTemp).Abs().Celsius > 0.5 &&
                        (newHumidity - oldHumidity).Percent > 0.05);
            }
            return false;
        }
    );

    sensor?.Subscribe(consumer);

    if (sensor != null)
    {
        sensor.Updated += (sender, result) =>
        {
            Resolver.Log.Info($"  Concentration: {result.New.Concentration?.PartsPerMillion:N0}ppm");
            Resolver.Log.Info($"  Temperature: {result.New.Temperature?.Celsius:N1}C");
            Resolver.Log.Info($"  Relative Humidity: {result.New.Humidity:N0}%");
        };
    }

    sensor?.StartUpdating(TimeSpan.FromSeconds(6));

    return base.Initialize();
}

Sample project(s) available on GitHub

Class Scd40

Represents an SCD40 C02 sensor

Assembly: Scd4x.dll

View Source

Declaration

public class Scd40 : Scd4xBase, IObservable<IChangeResult<(Concentration? Concentration, Temperature? Temperature, RelativeHumidity? Humidity)>>, ISamplingSensor<(Concentration? Concentration, Temperature? Temperature, RelativeHumidity? Humidity)>, ISensor<(Concentration? Concentration, Temperature? Temperature, RelativeHumidity? Humidity)>, ITemperatureSensor, ISamplingSensor<Temperature>, ISensor<Temperature>, IHumiditySensor, ISamplingSensor<RelativeHumidity>, ISensor<RelativeHumidity>, ICO2ConcentrationSensor, ISamplingSensor<Concentration>, ISensor<Concentration>, ISensor, ISamplingSensor, II2cPeripheral

Inheritance: System.Object -> Meadow.Foundation.ObservableBase<UNIT>

Implements:

Expand

System.IObservable<Meadow.IChangeResult<System.ValueTuple<System.Nullable<Meadow.Units.Concentration>,System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>>, Meadow.Peripherals.Sensors.ISamplingSensor<System.ValueTuple<System.Nullable<Meadow.Units.Concentration>,System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>, Meadow.Peripherals.Sensors.ISensor<System.ValueTuple<System.Nullable<Meadow.Units.Concentration>,System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>, Meadow.Peripherals.Sensors.ITemperatureSensor, Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Temperature>, Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Temperature>, Meadow.Peripherals.Sensors.Atmospheric.IHumiditySensor, Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.RelativeHumidity>, Meadow.Peripherals.Sensors.ISensor<Meadow.Units.RelativeHumidity>, Meadow.Peripherals.Sensors.Environmental.ICO2ConcentrationSensor, Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Concentration>, Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Concentration>, Meadow.Peripherals.Sensors.ISensor, Meadow.Peripherals.Sensors.ISamplingSensor, Meadow.Hardware.II2cPeripheral

Implements

• System.IObservable<Meadow.IChangeResult<System.ValueTuple<System.Nullable<Meadow.Units.Concentration>,System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>>
• Meadow.Peripherals.Sensors.ISamplingSensor<System.ValueTuple<System.Nullable<Meadow.Units.Concentration>,System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>
• Meadow.Peripherals.Sensors.ISensor<System.ValueTuple<System.Nullable<Meadow.Units.Concentration>,System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>
• Meadow.Peripherals.Sensors.ITemperatureSensor
• Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Temperature>
• Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Temperature>
• Meadow.Peripherals.Sensors.Atmospheric.IHumiditySensor
• Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.RelativeHumidity>
• Meadow.Peripherals.Sensors.ISensor<Meadow.Units.RelativeHumidity>
• Meadow.Peripherals.Sensors.Environmental.ICO2ConcentrationSensor
• Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Concentration>
• Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Concentration>
• Meadow.Peripherals.Sensors.ISensor
• Meadow.Peripherals.Sensors.ISamplingSensor
• Meadow.Hardware.II2cPeripheral