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 MeadowApp()
{
    Console.WriteLine("Initializing");

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

    // classical .NET events can also be used:
    sensor.Updated += (sender, result) => {
        Console.WriteLine($"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 => Console.WriteLine($"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);

    //==== one-off read
    ReadConditions().Wait();

    // start updating
    sensor.StartUpdating(TimeSpan.FromMilliseconds(500));
}

protected async Task ReadConditions()
{
    var result = await sensor.Read();
    Console.WriteLine("Initial Readings:");
    Console.WriteLine($"Accel: [X:{result.X.MetersPerSecondSquared:N2}," +
        $"Y:{result.Y.MetersPerSecondSquared:N2}," +
        $"Z:{result.Z.MetersPerSecondSquared:N2} (m/s^2)]");
}

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> SensorBase<Acceleration3D> SamplingSensorBase<Acceleration3D> Adxl3xxBase > Adxl335
Implements	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) SamplingSensorBase<Acceleration3D>.StartUpdating(Nullable<TimeSpan>) SamplingSensorBase<Acceleration3D>.StopUpdating() SensorBase<Acceleration3D>.Updated SensorBase<Acceleration3D>.samplingLock SensorBase<Acceleration3D>.SamplingTokenSource SensorBase<Acceleration3D>.Conditions SensorBase<Acceleration3D>.IsSampling SensorBase<Acceleration3D>.UpdateInterval SensorBase<Acceleration3D>.RaiseEventsAndNotify(IChangeResult<Acceleration3D>) SensorBase<Acceleration3D>.Read() ObservableBase<Acceleration3D>.observers ObservableBase<Acceleration3D>.NotifyObservers(IChangeResult<Acceleration3D>) Meadow.Foundation.ObservableBase<Acceleration3D>.Subscribe(IObserver<>) Meadow.Foundation.ObservableBase<Acceleration3D>.CreateObserver(Action<>, System.Nullable<Predicate<Meadow.IChangeResult<UNIT>>>)
Namespace	Meadow.Foundation.Sensors.Motion
Assembly	Adxl3xx.dll

Syntax

public class Adxl335 : Adxl3xxBase, IAccelerometer

Constructors

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

Create a new ADXL335 sensor object.

Declaration

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

Parameters

Type	Name	Description
IAnalogInputController	device	Device that has the analog pins.
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.