Remarks

Hmc5883
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

Code Example

Hmc5883 sensor;

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

    sensor = new Hmc5883(Device.CreateI2cBus());

    // classical .NET events can also be used:
    sensor.Updated += (sender, result) => {
        Resolver.Log.Info($"Direction: [X:{result.New.X:N2}," +
            $"Y:{result.New.Y:N2}," +
            $"Z:{result.New.Z:N2}]");

        Resolver.Log.Info($"Heading: [{Hmc5883.DirectionToHeading(result.New).DecimalDegrees:N2}] degrees");
    };

    // Example that uses an IObservable subscription to only be notified when the filter is satisfied
    var consumer = Hmc5883.CreateObserver(
        handler: result => Resolver.Log.Info($"Observer: [x] changed by threshold; new [x]: X:{Hmc5883.DirectionToHeading(result.New):N2}," +
                $" old: X:{((result.Old != null) ? Hmc5883.DirectionToHeading(result.Old.Value) : "n/a"):N2} degrees"),
        // only notify if there's a greater than 5° of heading change
        filter: result => {
            if (result.Old is { } old) { //c# 8 pattern match syntax. checks for !null and assigns var.
                return (Hmc5883.DirectionToHeading(result.New - old) > new Azimuth(5));
            }
            return false;
        });

    sensor.Subscribe(consumer);

    return Task.CompletedTask;
}

public async override Task Run()
{
    var result = await sensor.Read();
    Resolver.Log.Info("Initial Readings:");
    Resolver.Log.Info($"Direction: [X:{result.X:N2}," +
        $"Y:{result.Y:N2}," +
        $"Z:{result.Z:N2}]");

    Resolver.Log.Info($"Heading: [{Hmc5883.DirectionToHeading(result).DecimalDegrees:N2}] degrees");

    sensor.StartUpdating(TimeSpan.FromMilliseconds(1000));
}

Sample project(s) available on GitHub

Characteristic	Locus
Inheritance	System.Object ObservableBase<Vector> SamplingSensorBase<Vector> PollingSensorBase<Vector> ByteCommsSensorBase<Vector> > Hmc5883 > Qmc5883
Implements	ISamplingSensor<Vector> ISamplingSensor<Vector> IDisposable
Inherited Members	ByteCommsSensorBase<Vector>.Peripheral ByteCommsSensorBase<Vector>.ReadBuffer ByteCommsSensorBase<Vector>.WriteBuffer ByteCommsSensorBase<Vector>.Init(Int32, Int32) ByteCommsSensorBase<Vector>.Dispose(Boolean) ByteCommsSensorBase<Vector>.Dispose() PollingSensorBase<Vector>.StartUpdating(Nullable<TimeSpan>) PollingSensorBase<Vector>.StopUpdating() SamplingSensorBase<Vector>.samplingLock SamplingSensorBase<Vector>.Updated SamplingSensorBase<Vector>.SamplingTokenSource SamplingSensorBase<Vector>.Conditions SamplingSensorBase<Vector>.IsSampling SamplingSensorBase<Vector>.UpdateInterval SamplingSensorBase<Vector>.RaiseEventsAndNotify(IChangeResult<>) SamplingSensorBase<Vector>.Read() ObservableBase<Vector>.observers ObservableBase<Vector>.NotifyObservers(IChangeResult<>) Meadow.Foundation.ObservableBase<Meadow.Foundation.Spatial.Vector>.Subscribe(IObserver<>) Meadow.Foundation.ObservableBase<Meadow.Foundation.Spatial.Vector>.CreateObserver(Action<>, System.Nullable<Predicate<IChangeResult<UNIT>>>)
Namespace	Meadow.Foundation.Sensors.Motion
Assembly	Hmc5883.dll

Syntax

public class Hmc5883 : ByteCommsSensorBase<Vector>, ISamplingSensor<Vector>, ISamplingSensor<Vector>, IDisposable

Constructors

Hmc5883(II2cBus, Byte, Hmc5883.GainLevels, Hmc5883.MeasuringModes, Hmc5883.DataOutputRates, Hmc5883.SampleAmounts, Hmc5883.MeasurementConfigurations)

Create a new Hmc5883 object

Declaration

public Hmc5883(II2cBus i2cBus, byte address = null, Hmc5883.GainLevels gain = default(Hmc5883.GainLevels), Hmc5883.MeasuringModes measuringMode = default(Hmc5883.MeasuringModes), Hmc5883.DataOutputRates outputRate = default(Hmc5883.DataOutputRates), Hmc5883.SampleAmounts samplesAmount = default(Hmc5883.SampleAmounts), Hmc5883.MeasurementConfigurations measurementConfig = default(Hmc5883.MeasurementConfigurations))

Parameters

Type	Name	Description
II2cBus	i2cBus	The I2C bus
System.Byte	address	The I2C address
Hmc5883.GainLevels	gain	Gain
Hmc5883.MeasuringModes	measuringMode	Measuring mode
Hmc5883.DataOutputRates	outputRate	Output rate
Hmc5883.SampleAmounts	samplesAmount	Samples amount
Hmc5883.MeasurementConfigurations	measurementConfig	Measurement configuration

Properties

DeviceStatus

HMC5883L Status

Declaration

public Hmc5883.Statuses DeviceStatus { get; }

Property Value

Type	Description
Hmc5883.Statuses

Direction

HMC5883L Direction as a Vector

Declaration

public Vector? Direction { get; }

Property Value

Type	Description
System.Nullable<Vector>

Heading

HMC5883L Heading (DEG)

Declaration

public Azimuth? Heading { get; }

Property Value

Type	Description
System.Nullable<Azimuth>

Methods

DirectionToHeading(Vector)

Calculate heading

Declaration

public static Azimuth DirectionToHeading(Vector direction)

Parameters

Type	Name	Description
Vector	direction	HMC5883L Direction

Returns

Type	Description
Azimuth	Heading (DEG)

Initialize()

Initalize the sensor

Declaration

protected virtual void Initialize()

RaiseEventsAndNotify(IChangeResult<Vector>)

Raise events for subcribers and notify of value changes

Declaration

protected override void RaiseEventsAndNotify(IChangeResult<Vector> changeResult)

Parameters

Type	Name	Description
IChangeResult<Vector>	changeResult	The updated sensor data

ReadSensor()

Reads data from the sensor

Declaration

protected override Task<Vector> ReadSensor()

Returns

Type	Description
Task<Vector>	The latest sensor reading

Overrides

Meadow.Foundation.SamplingSensorBase<Meadow.Foundation.Spatial.Vector>.ReadSensor()

Events

DirectionUpdated

Event to be raised when the compass changes

Declaration

public event EventHandler<IChangeResult<Vector>> DirectionUpdated

Event Type

Type	Description
EventHandler<IChangeResult<Vector>>