Characteristic	Locus
Inheritance	object PortBase<IAnalogChannelInfo> AnalogPortBase > AnalogInputPortBase > AnalogInputPort
Implements	IAnalogInputPort IAnalogPort IPort<IAnalogChannelInfo> IDisposable IObservable<IChangeResult<Voltage>>
Inherited Members	PortBase<IAnalogChannelInfo>.disposed PortBase<IAnalogChannelInfo>.Channel PortBase<IAnalogChannelInfo>.Pin PortBase<IAnalogChannelInfo>.Dispose(bool) PortBase<IAnalogChannelInfo>.Dispose() object.Equals(object) object.Equals(object, object) object.GetHashCode() object.GetType() object.MemberwiseClone() object.ReferenceEquals(object, object) object.ToString()
Namespace	Meadow.Hardware
Assembly	Meadow.Contracts.dll

Syntax

public abstract class AnalogInputPortBase : AnalogPortBase, IAnalogInputPort, IAnalogPort, IPort<IAnalogChannelInfo>, IDisposable, IObservable<IChangeResult<Voltage>>

Constructors

AnalogInputPortBase(IPin, IAnalogChannelInfo, int, TimeSpan, Voltage)

Initializes a new instance of the AnalogInputPortBase class.

Declaration

protected AnalogInputPortBase(IPin pin, IAnalogChannelInfo channel, int sampleCount, TimeSpan sampleInterval, Voltage referenceVoltage)

Parameters

Type	Name	Description
IPin	pin	The pin associated with the analog input port.
IAnalogChannelInfo	channel	The channel information for the analog input port.
int	sampleCount	The number of samples to be taken during each reading.
TimeSpan	sampleInterval	The time interval between samples during each reading.
Voltage	referenceVoltage	The reference voltage used for analog-to-digital conversion.

Properties

BufferSyncRoot

Gets the internal synchronization object for the analog buffer

Declaration

protected object BufferSyncRoot { get; }

Property Value

Type	Description
object

Observers

A collection of state observers

Declaration

protected List<IObserver<IChangeResult<Voltage>>> Observers { get; }

Property Value

Type	Description
List<IObserver<IChangeResult<Voltage>>>

ReferenceVoltage

The reference voltage being used for the ADC comparison

Declaration

public Voltage ReferenceVoltage { get; protected set; }

Property Value

Type	Description
Voltage

SampleCount

Number of samples to take per reading. If > 1 then the port will take multiple readings and These are automatically averaged to reduce noise, a process known as oversampling.

Declaration

public int SampleCount { get; protected set; }

Property Value

Type	Description
int

SampleInterval

Duration in between samples when oversampling.

Declaration

public TimeSpan SampleInterval { get; protected set; }

Property Value

Type	Description
TimeSpan

UpdateInterval

A TimeSpan that specifies how long to wait between readings. This value influences how often *Updated events are raised and IObservable consumers are notified.

Declaration

public TimeSpan UpdateInterval { get; protected set; }

Property Value

Type	Description
TimeSpan

Voltage

Gets the average value of the values in the buffer. Use in conjunction with StartUpdating() for long-running analog sampling. For occasional sampling, use Read().

Declaration

public virtual Voltage Voltage { get; }

Property Value

Type	Description
Voltage	The average buffer value.

VoltageSampleBuffer

Gets the sample buffer. Make sure to call StartUpdating() before use.

Declaration

public Voltage[] VoltageSampleBuffer { get; }

Property Value

Type	Description
Voltage[]	The sample buffer.

Methods

ConvertReadingToVoltage(int)

Converts a raw 32-bit reading to a scaled value in volts

Declaration

protected double ConvertReadingToVoltage(int rawReading)

Parameters

Type	Name	Description
int	rawReading	The raw reading to convert

Returns

Type	Description
double

RaiseChangedAndNotify(IChangeResult<Voltage>)

Raises the Changed event and notifies the observers with the specified change result.

Declaration

protected void RaiseChangedAndNotify(IChangeResult<Voltage> changeResult)

Parameters

Type	Name	Description
IChangeResult<Voltage>	changeResult	The change result to be passed to the event and observers.

Read()

Convenience method to get the current voltage. For frequent reads, use StartUpdating() and StopUpdating() in conjunction with the SampleBuffer.

Declaration

public abstract Task<Voltage> Read()

Returns

Type	Description
Task<Voltage>

StartUpdating(TimeSpan?)

Starts continuously sampling the analog port.

This method also starts raising Changed events and IObservable subscribers getting notified. Use the readIntervalDuration parameter to specify how often events and notifications are raised/sent.

Declaration

public abstract void StartUpdating(TimeSpan? updateInterval)

Parameters

Type	Name	Description
TimeSpan?	updateInterval

StopUpdating()

Stops sampling the analog port.

Declaration

public abstract void StopUpdating()

Subscribe(IObserver<IChangeResult<Voltage>>)

Subscribes an observer to receive notifications of voltage change.

Declaration

public IDisposable Subscribe(IObserver<IChangeResult<Voltage>> observer)

Parameters

Type	Name	Description
IObserver<IChangeResult<Voltage>>	observer	The observer to subscribe.

Returns

Type	Description
IDisposable	An IDisposable object that can be used to unsubscribe from the observer.

Events

Updated

Raised when the value of the reading changes.

Declaration

public event EventHandler<IChangeResult<Voltage>> Updated

Event Type

Type	Description
EventHandler<IChangeResult<Voltage>>