Meadow.Foundation.Sensors.Atmospheric.Sht4x

Sht4x
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

Code Example

Sht4x sensor;

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

    sensor = new Sht4x(Device.CreateI2cBus());

    var consumer = Sht4x.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 is { } old)
            {
                return (
                (result.New.Temperature.Value - old.Temperature.Value).Abs().Celsius > 0.5
                &&
                (result.New.Humidity.Value.Percent - old.Humidity.Value.Percent) > 0.05
                );
            }
            return false;
        }
    );
    sensor.Subscribe(consumer);

    sensor.Updated += (sender, result) =>
    {
        Resolver.Log.Info($"  Temperature: {result.New.Temperature?.Celsius:N2}C");
        Resolver.Log.Info($"  Relative Humidity: {result.New.Humidity:N2}%");
    };

    return Task.CompletedTask;
}

public override async Task Run()
{
    var conditions = await sensor.Read();
    Resolver.Log.Info("Initial Readings:");
    Resolver.Log.Info($"  Temperature: {conditions.Temperature?.Celsius:N2}C");
    Resolver.Log.Info($"  Relative Humidity: {conditions.Humidity?.Percent:N2}%");

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

Sample project(s) available on GitHub

Wiring Example

To wire a Sht4x to your Meadow board, connect the following:

Sht4x	Meadow Pin
GND	GND
SCL	D08 (SCL)
SDA	D07 (SDA)
VCC	3V3

Class Sht4x

Represent a SHT4x temperature and humidity sensor (SHT40, SHT41, SHT45, etc.)

Assembly: Sht4x.dll

View Source

Declaration

public class Sht4x : ByteCommsSensorBase<(Temperature? Temperature, RelativeHumidity? Humidity)>, IObservable<IChangeResult<(Temperature? Temperature, RelativeHumidity? Humidity)>>, ISamplingSensor<(Temperature? Temperature, RelativeHumidity? Humidity)>, ISensor<(Temperature? Temperature, RelativeHumidity? Humidity)>, IDisposable, ITemperatureSensor, ISamplingSensor<Temperature>, ISensor<Temperature>, IHumiditySensor, ISamplingSensor<RelativeHumidity>, ISensor<RelativeHumidity>, ISensor, ISamplingSensor, II2cPeripheral

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

Implements:

Expand

System.IObservable<Meadow.IChangeResult<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>>, Meadow.Peripherals.Sensors.ISamplingSensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>, Meadow.Peripherals.Sensors.ISensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>, System.IDisposable, 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.ISensor, Meadow.Peripherals.Sensors.ISamplingSensor, Meadow.Hardware.II2cPeripheral

Properties

ReadPrecision

Precision of sensor reading

View Source

Declaration

public Sht4x.Precision ReadPrecision { get; protected set; }

Temperature

The current temperature

View Source

Declaration

public Temperature? Temperature { get; }

Humidity

The current humidity

View Source

Declaration

public RelativeHumidity? Humidity { get; }

DefaultI2cAddress

The default I2C address for the peripheral

View Source

Declaration

public byte DefaultI2cAddress { get; }

Methods

RaiseEventsAndNotify(IChangeResult<(Temperature? Temperature, RelativeHumidity? Humidity)>)

Raise events for subscribers

View Source

Declaration

protected override void RaiseEventsAndNotify(IChangeResult<(Temperature? Temperature, RelativeHumidity? Humidity)> changeResult)

Parameters

Type	Name
Meadow.IChangeResult<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>	changeResult

GetDelayForPrecision(Precision)

Returns the appropriate delay in ms for the set precision

View Source

Declaration

protected int GetDelayForPrecision(Sht4x.Precision precision)

Returns

System.Int32

Parameters

Type	Name	Description
Meadow.Foundation.Sensors.Atmospheric.Sht4x.Precision	precision	Precision to calculate delay

ReadSensor()

Get a reading from the sensor and set the Temperature and Humidity properties.

View Source

Declaration

protected override Task<(Temperature? Temperature, RelativeHumidity? Humidity)> ReadSensor()

Returns

System.Threading.Tasks.Task<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>

Implements

• System.IObservable<Meadow.IChangeResult<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>>
• Meadow.Peripherals.Sensors.ISamplingSensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>
• Meadow.Peripherals.Sensors.ISensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>>>
• System.IDisposable
• 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.ISensor
• Meadow.Peripherals.Sensors.ISamplingSensor
• Meadow.Hardware.II2cPeripheral