Class Pcx857x

Represents a Pcx857x I2C IO Expander

Assembly: Pcx857x.dll

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public abstract class Pcx857x : IDigitalOutputController, IDigitalInputController, IDigitalInterruptController, IPinController, II2cPeripheral, IDisposable

Derived:
Meadow.Foundation.ICs.IOExpanders.Pcx8574, Meadow.Foundation.ICs.IOExpanders.Pcx8575

Implements:
Meadow.Hardware.IDigitalOutputController, Meadow.Hardware.IDigitalInputController, Meadow.Hardware.IDigitalInterruptController, Meadow.Hardware.IPinController, Meadow.Hardware.II2cPeripheral, System.IDisposable

Properties

NumberOfPins

The number of IO pins available on the device

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public abstract int NumberOfPins { get; }

DefaultI2cAddress

The default I2C address for the peripheral

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public byte DefaultI2cAddress { get; }

IsDisposed

Is the object disposed

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public bool IsDisposed { get; }

Fields

createdPorts

Did we create the port(s) used by the peripheral

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protected bool createdPorts

i2cComms

The I2C Communications object

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protected readonly II2cCommunications i2cComms

Methods

GetAddressFromPins(bool, bool, bool, bool)

Helper method to get address from address pin configuration

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public static byte GetAddressFromPins(bool pinA0, bool pinA1, bool pinA2, bool isATypeDevice = false)

Returns

System.Byte: The device address

Parameters

Type	Name	Description
`System.Boolean`	pinA0	State of A0 address pin - true if high
`System.Boolean`	pinA1	State of A1 address pin - true if high
`System.Boolean`	pinA2	State of A2 address pin - true if high
`System.Boolean`	isATypeDevice	Is an A hardware variant, this shifts the address returned by 24

CreateDigitalOutputPort(IPin, bool, OutputType)

Creates an IDigitalOutputPort on the specified pin.

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public IDigitalOutputPort CreateDigitalOutputPort(IPin pin, bool initialState = false, OutputType initialOutputType = OutputType.PushPull)

Returns

Meadow.Hardware.IDigitalOutputPort

Parameters

Type	Name	Description
`Meadow.Hardware.IPin`	pin	The pin on which to create the port.
`System.Boolean`	initialState	The default initial state of the port,
either `LOW` (`false`), or `HIGH` (`true`).
`Meadow.Hardware.OutputType`	initialOutputType	Whether the port is initially configured
as PushPull or OpenDrain. PushPull by default.

CreateDigitalInputPort(IPin, ResistorMode)

Creates an IDigitalInputPort on the specified pin.

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public IDigitalInputPort CreateDigitalInputPort(IPin pin, ResistorMode resistorMode)

Returns

Meadow.Hardware.IDigitalInputPort

Parameters

Type	Name	Description
`Meadow.Hardware.IPin`	pin	The pin on which to create the port.
`Meadow.Hardware.ResistorMode`	resistorMode	The `ResistorMode` specifying whether an

        external pull-up/pull-down resistor is used, or an internal pull-up/pull-down
        resistor should be configured for default state. |

CreateDigitalInterruptPort(IPin, InterruptMode, ResistorMode)

Creates a new DigitalInputPort using the specified pin

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public IDigitalInterruptPort CreateDigitalInterruptPort(IPin pin, InterruptMode interruptMode = InterruptMode.None, ResistorMode resistorMode = ResistorMode.Disabled)

Returns

Meadow.Hardware.IDigitalInterruptPort: IDigitalInterruptPort

Parameters

Type	Name	Description
`Meadow.Hardware.IPin`	pin	The pin representing the port
`Meadow.Hardware.InterruptMode`	interruptMode	The port interrupt mode
`Meadow.Hardware.ResistorMode`	resistorMode	The port resistor mode

CreateDigitalInterruptPort(IPin, InterruptMode, ResistorMode, TimeSpan)

Creates a new DigitalInputPort using the specified pin

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public IDigitalInterruptPort CreateDigitalInterruptPort(IPin pin, InterruptMode interruptMode, ResistorMode resistorMode, TimeSpan debounceDuration)

Returns

Meadow.Hardware.IDigitalInterruptPort: IDigitalInterruptPort

Parameters

Type	Name	Description
`Meadow.Hardware.IPin`	pin	The pin representing the port
`Meadow.Hardware.InterruptMode`	interruptMode	The port interrupt mode
`Meadow.Hardware.ResistorMode`	resistorMode	The port resistor mode
`System.TimeSpan`	debounceDuration	The debounce duration

CreateDigitalInterruptPort(IPin, InterruptMode, ResistorMode, TimeSpan, TimeSpan)

Creates a new DigitalInputPort using the specified pin

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public IDigitalInterruptPort CreateDigitalInterruptPort(IPin pin, InterruptMode interruptMode, ResistorMode resistorMode, TimeSpan debounceDuration, TimeSpan glitchDuration)

Returns

Meadow.Hardware.IDigitalInterruptPort: IDigitalInterruptPort

Parameters

Type	Name	Description
`Meadow.Hardware.IPin`	pin	The pin representing the port
`Meadow.Hardware.InterruptMode`	interruptMode	The port interrupt mode
`Meadow.Hardware.ResistorMode`	resistorMode	The port resistor mode
`System.TimeSpan`	debounceDuration	The debounce duration
`System.TimeSpan`	glitchDuration	The glitch duration - not configurable on Mcpxxxx

GetPin(string)

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public abstract IPin GetPin(string pinName)

Returns

Meadow.Hardware.IPin

Parameters

Type	Name
`System.String`	pinName

IsValidPin(IPin)

Checks if a pin exists on the Pcx857x

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protected abstract bool IsValidPin(IPin pin)

Returns

System.Boolean

Parameters

Type	Name
`Meadow.Hardware.IPin`	pin

ReadState()

Reads the peripheral state register for 8 pin devices

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protected abstract ushort ReadState()

Returns

System.UInt16

WriteState(ushort)

Writes to the peripheral state register

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protected abstract void WriteState(ushort state)

Parameters

Type	Name
`System.UInt16`	state

SetState(ushort)

Writes to the peripheral state register and saves internal output state

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protected abstract void SetState(ushort state)

Parameters

Type	Name
`System.UInt16`	state

SetPinDirection(bool, byte)

Set the pin direction

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protected abstract void SetPinDirection(bool input, byte pinKey)

Parameters

Type	Name	Description
`System.Boolean`	input	true for input, false for output
`System.Byte`	pinKey	The pin key value

AllOff()

Convenience method to turn all outputs off

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public void AllOff()

AllOn()

Convenience method to turn all outputs on

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public void AllOn()

GetPinState(IPin)

Retrieves the state of a pin

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protected abstract bool GetPinState(IPin pin)

Returns

System.Boolean

Parameters

Type	Name	Description
`Meadow.Hardware.IPin`	pin	The pin to query

SetPinState(IPin, bool)

Sets the state of a pin

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protected abstract void SetPinState(IPin pin, bool state)

Parameters

Type	Name	Description
`Meadow.Hardware.IPin`	pin	The pin to affect
`System.Boolean`	state	<b>True</b> to set the pin state high, <b>False</b> to set it low

Dispose(bool)

Dispose of the object

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protected virtual void Dispose(bool disposing)

Parameters

Type	Name	Description
`System.Boolean`	disposing	Is disposing

Dispose()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.

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public void Dispose()

Implements

Meadow.Hardware.IDigitalOutputController
Meadow.Hardware.IDigitalInputController
Meadow.Hardware.IDigitalInterruptController
Meadow.Hardware.IPinController
Meadow.Hardware.II2cPeripheral
System.IDisposable