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Meadow.Foundation.Sensors.Atmospheric.Bme688

Bme688
StatusStatus badge: working
Source codeGitHub
Datasheet(s)GitHub
NuGet packageNuGet Gallery for Meadow.Foundation.Sensors.Atmospheric.Bme68x

Code Example​

Bme688? sensor;

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

    //CreateSpiSensor();
    CreateI2CSensor();

    //uncomment to enable on sensor heater for gas readings
    //EnableGasHeater();

    var consumer = Bme688.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($"  Temperature: {result.New.Temperature?.Celsius:N2}C");
            Resolver.Log.Info($"  Relative Humidity: {result.New.Humidity:N2}%");
            Resolver.Log.Info($"  Pressure: {result.New.Pressure?.Millibar:N2}mbar ({result.New.Pressure?.Pascal:N2}Pa)");
            if (sensor.GasConversionIsEnabled)
            {
                Resolver.Log.Info($"  Gas Resistance: {result.New.GasResistance:N0}Ohms");
            }
        };
    }

    sensor?.StartUpdating(TimeSpan.FromSeconds(2));

    ReadConditions().Wait();

    return base.Initialize();
}

void EnableGasHeater()
{
    if (sensor != null)
    {
        sensor.GasConversionIsEnabled = true;
        sensor.HeaterIsEnabled = true;
        sensor.ConfigureHeatingProfile(Bme688.HeaterProfileType.Profile1, new Temperature(300), TimeSpan.FromMilliseconds(100), new Temperature(22));
        sensor.HeaterProfile = Bme688.HeaterProfileType.Profile1;
    }
}

void CreateSpiSensor()
{
    Resolver.Log.Info("Create BME688 sensor with SPI...");

    var spiBus = Device.CreateSpiBus();
    sensor = new Bme688(spiBus, Device.CreateDigitalOutputPort(Device.Pins.D01));
}

void CreateI2CSensor()
{
    Resolver.Log.Info("Create BME688 sensor with I2C...");

    var i2c = Device.CreateI2cBus();
    sensor = new Bme688(i2c, (byte)Bme688.Addresses.Address_0x76);
}

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

    var (Temperature, Humidity, Pressure, Resistance) = await sensor.Read();

    Resolver.Log.Info("Initial Readings:");
    Resolver.Log.Info($"  Temperature: {Temperature?.Celsius:N2}C");
    Resolver.Log.Info($"  Pressure: {Pressure?.Hectopascal:N2}hPa");
    Resolver.Log.Info($"  Relative Humidity: {Humidity?.Percent:N2}%");
    Resolver.Log.Info($"  Gas Resistance: {Resistance?.Ohms:N0}Ohms");
}

Sample project(s) available on GitHub

Wiring Example​

To wire a BME688 to your Meadow board, connect the following:

Wiring a BME680 sensor to Meadow, which has near-identical pins to a BME688 package.

Class Bme688

Represents a BME688 Temperature, Pressure, Humidity and VOS sensor

Assembly: Bme68x.dll​
View Source​
Declaration
public class Bme688 : Bme68x, IObservable<IChangeResult<(Temperature? Temperature, RelativeHumidity? Humidity, Pressure? Pressure, Resistance? GasResistance)>>, ISamplingSensor<(Temperature? Temperature, RelativeHumidity? Humidity, Pressure? Pressure, Resistance? GasResistance)>, ISensor<(Temperature? Temperature, RelativeHumidity? Humidity, Pressure? Pressure, Resistance? GasResistance)>, ITemperatureSensor, ISamplingSensor<Temperature>, ISensor<Temperature>, IHumiditySensor, ISamplingSensor<RelativeHumidity>, ISensor<RelativeHumidity>, IBarometricPressureSensor, ISamplingSensor<Pressure>, ISensor<Pressure>, IGasResistanceSensor, ISamplingSensor<Resistance>, ISensor<Resistance>, ISensor, ISamplingSensor, ISpiPeripheral, II2cPeripheral, ISleepAwarePeripheral, IDisposable

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>,System.Nullable<Meadow.Units.Pressure>,System.Nullable<Meadow.Units.Resistance>>>>, Meadow.Peripherals.Sensors.ISamplingSensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>,System.Nullable<Meadow.Units.Pressure>,System.Nullable<Meadow.Units.Resistance>>>, Meadow.Peripherals.Sensors.ISensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>,System.Nullable<Meadow.Units.Pressure>,System.Nullable<Meadow.Units.Resistance>>>, 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.Atmospheric.IBarometricPressureSensor, Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Pressure>, Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Pressure>, Meadow.Peripherals.Sensors.Environmental.IGasResistanceSensor, Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Resistance>, Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Resistance>, Meadow.Peripherals.Sensors.ISensor, Meadow.Peripherals.Sensors.ISamplingSensor, Meadow.Hardware.ISpiPeripheral, Meadow.Hardware.II2cPeripheral, Meadow.ISleepAwarePeripheral, System.IDisposable

Implements​

  • System.IObservable<Meadow.IChangeResult<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>,System.Nullable<Meadow.Units.Pressure>,System.Nullable<Meadow.Units.Resistance>>>>
  • Meadow.Peripherals.Sensors.ISamplingSensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>,System.Nullable<Meadow.Units.Pressure>,System.Nullable<Meadow.Units.Resistance>>>
  • Meadow.Peripherals.Sensors.ISensor<System.ValueTuple<System.Nullable<Meadow.Units.Temperature>,System.Nullable<Meadow.Units.RelativeHumidity>,System.Nullable<Meadow.Units.Pressure>,System.Nullable<Meadow.Units.Resistance>>>
  • 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.Atmospheric.IBarometricPressureSensor
  • Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Pressure>
  • Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Pressure>
  • Meadow.Peripherals.Sensors.Environmental.IGasResistanceSensor
  • Meadow.Peripherals.Sensors.ISamplingSensor<Meadow.Units.Resistance>
  • Meadow.Peripherals.Sensors.ISensor<Meadow.Units.Resistance>
  • Meadow.Peripherals.Sensors.ISensor
  • Meadow.Peripherals.Sensors.ISamplingSensor
  • Meadow.Hardware.ISpiPeripheral
  • Meadow.Hardware.II2cPeripheral
  • Meadow.ISleepAwarePeripheral
  • System.IDisposable