Meadow.Foundation.Sensors.Motion.Hmc5883 1.2.1.11-beta

Meadow.Foundation.Sensors.Motion.Hmc5883

Hmc5883 / Qmc5883 I2C digital compass

The Hmc5883 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 of Wilderness Labs open-source projects, including samples, visit github.com/wildernesslabs

Usage

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));
}