Remarks

Adxl335
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

The ADXL335 is a low power accelerometer capable of measuring +/- 3g of acceleration along three axes. The ADXL335 is controlled via I2C.

Code Example

Adxl335 sensor;

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

    // create the sensor driver
    sensor = new Adxl335(Device.Pins.A00, Device.Pins.A01, Device.Pins.A02, null);

    // classical .NET events can also be used:
    sensor.Updated += (sender, result) =>
    {
        Resolver.Log.Info($"Accel: [X:{result.New.X.MetersPerSecondSquared:N2}," +
            $"Y:{result.New.Y.MetersPerSecondSquared:N2}," +
            $"Z:{result.New.Z.MetersPerSecondSquared:N2} (m/s^2)]");
    };

    // Example that uses an IObservable subscription to only be notified when the filter is satisfied
    var consumer = Adxl335.CreateObserver(
        handler: result => Resolver.Log.Info($"Observer: [x] changed by threshold; new [x]: X:{result.New.X:N2}, old: X:{result.Old?.X:N2}"),
        // only notify if there's a greater than 1G change in the Z direction
        filter: result =>
        {
            if (result.Old is { } old)
            { //c# 8 pattern match syntax. checks for !null and assigns var.
                return ((result.New - old).Z > new Acceleration(1, AU.Gravity));
            }
            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($"Accel: [X:{result.X.MetersPerSecondSquared:N2}," +
        $"Y:{result.Y.MetersPerSecondSquared:N2}," +
        $"Z:{result.Z.MetersPerSecondSquared:N2} (m/s^2)]");

    sensor.StartUpdating(TimeSpan.FromMilliseconds(500));
}

Sample project(s) available on GitHub

Code Sample

public class MeadowApp : App<F7Micro, MeadowApp>
{
    Adxl335 sensor;

    public MeadowApp()
    {
        sensor = new Adxl335(Device, Device.Pins.A01, Device.Pins.A02, Device.Pins.A03, 500);

        sensor.AccelerationChanged += Sensor_AccelerationChanged;
    }

    private void Sensor_AccelerationChanged(object sender, Meadow.Foundation.Sensors.SensorVectorEventArgs e)
    {
        Console.WriteLine($"X: {e.CurrentValue.X}, Y: {e.CurrentValue.Y}, Z: {e.CurrentValue.Z}");
    }
}

Sample projects available on GitHub

Purchasing

The ADXL335 sensor can be purchased on a breakout board from the following suppliers:

• Adafruit ADXL335
• Sparkfun ADXL335

Wiring Example

Characteristic	Locus
Inheritance	System.Object ObservableBase<Acceleration3D> SamplingSensorBase<Acceleration3D> PollingSensorBase<Acceleration3D> Adxl3xxBase > Adxl335
Implements	ISamplingSensor<Acceleration3D> ISamplingSensor<Acceleration3D> IAccelerometer
Inherited Members	Adxl3xxBase.Acceleration3DUpdated Adxl3xxBase.XAnalogIn Adxl3xxBase.YAnalogIn Adxl3xxBase.ZAnalogIn Adxl3xxBase.SupplyVoltage Adxl3xxBase.GravityRange Adxl3xxBase.Acceleration3D Adxl3xxBase.RaiseEventsAndNotify(IChangeResult<Acceleration3D>) Adxl3xxBase.ReadSensor() Adxl3xxBase.VoltageToGravity(Voltage) PollingSensorBase<Acceleration3D>.StartUpdating(Nullable<TimeSpan>) PollingSensorBase<Acceleration3D>.StopUpdating() SamplingSensorBase<Acceleration3D>.samplingLock SamplingSensorBase<Acceleration3D>.Updated SamplingSensorBase<Acceleration3D>.SamplingTokenSource SamplingSensorBase<Acceleration3D>.Conditions SamplingSensorBase<Acceleration3D>.IsSampling SamplingSensorBase<Acceleration3D>.UpdateInterval SamplingSensorBase<Acceleration3D>.RaiseEventsAndNotify(IChangeResult<>) SamplingSensorBase<Acceleration3D>.Read() ObservableBase<Acceleration3D>.observers ObservableBase<Acceleration3D>.NotifyObservers(IChangeResult<>) Meadow.Foundation.ObservableBase<Acceleration3D>.Subscribe(IObserver<>) Meadow.Foundation.ObservableBase<Acceleration3D>.CreateObserver(Action<>, System.Nullable<Predicate<IChangeResult<UNIT>>>)
Namespace	Meadow.Foundation.Sensors.Motion
Assembly	Adxl3xx.dll

Syntax

public class Adxl335 : Adxl3xxBase, ISamplingSensor<Acceleration3D>, ISamplingSensor<Acceleration3D>, IAccelerometer

Constructors

Adxl335(IPin, IPin, IPin, Nullable<Voltage>)

Create a new ADXL335 sensor object.

Declaration

public Adxl335(IPin xPin, IPin yPin, IPin zPin, Voltage? supplyVoltage)

Parameters

Type	Name	Description
IPin	xPin	Analog pin connected to the X axis output from the ADXL335 sensor.
IPin	yPin	Analog pin connected to the Y axis output from the ADXL335 sensor.
IPin	zPin	Analog pin connected to the Z axis output from the ADXL335 sensor.
System.Nullable<Voltage>	supplyVoltage	The voltage supplied to the sensor. Defaults to 3.3V if null.