org.eclipse.kura.gpio

Interface KuraGPIOPin

public interface KuraGPIOPin

The KuraGPIOPin class is used to access the GPIO resource.
The pin can be programmed either as an input or as an output. The way this is handled is implementation dependent.

Pins must be opened and closed before setting or getting values. Implementations, however, could automatically open a pin if it is closed when accessing it, or automatically close it when it is not needed anymore.

Status of input pins can be retrieved either with a call to getValue() or by attaching a PinStatusListener to the pin.

Method Summary

Methods

Modifier and Type	Method and Description
void	addPinStatusListener(PinStatusListener listener) Adds a PinStatusListener to this input pin.
void	close() Closes this pin and deallocates the resources needed to communicate with it. If there is a PinStatusListener attached to this pin, the implementation should remove it before closing the resource.
KuraGPIODirection	getDirection()
int	getIndex()
KuraGPIOMode	getMode()
String	getName()
KuraGPIOTrigger	getTrigger()
boolean	getValue() Used to get the current value of a pin, either output or input
boolean	isOpen()
void	open() Opens the pin and allocates the needed resources to communicate with it.
void	removePinStatusListener(PinStatusListener listener) Removes a PinStatusListener from this input pin. If the pin has no listeners attached, this method should fail silently.
void	setValue(boolean active) Used to set the value of an output pin.

Method Detail

setValue

void setValue(boolean active)
              throws KuraUnavailableDeviceException,
                     KuraClosedDeviceException,
                     IOException

Used to set the value of an output pin.

Parameters:

active - New state of the pin.

Throws:

KuraUnavailableDeviceException - when the GPIO resource is not available

KuraClosedDeviceException - when the GPIO resource has not yet been opened

IOException - if an I/O error occurs

getValue

boolean getValue()
                 throws KuraUnavailableDeviceException,
                        KuraClosedDeviceException,
                        IOException

Used to get the current value of a pin, either output or input

Returns:

true if the pin is in active state

Throws:

KuraUnavailableDeviceException - when the GPIO resource is not available

KuraClosedDeviceException - when the GPIO resource has not yet been opened

IOException - if an I/O error occurs

addPinStatusListener

void addPinStatusListener(PinStatusListener listener)
                          throws KuraClosedDeviceException,
                                 IOException

Adds a PinStatusListener to this input pin. The listener will be notified when the status of this input changes.
Attaching a listener to an output pin should not raise an exception, but will have no result.

Parameters:

listener - Listener to be added to this pin

Throws:

KuraClosedDeviceException - when the GPIO resource has not yet been opened

IOException - if an I/O error occurs

removePinStatusListener

void removePinStatusListener(PinStatusListener listener)
                             throws KuraClosedDeviceException,
                                    IOException

Removes a PinStatusListener from this input pin.
If the pin has no listeners attached, this method should fail silently.

Parameters:

listener - Listener to be removed from this pin

Throws:

KuraClosedDeviceException - when the GPIO resource has not yet been opened

IOException - if an I/O error occurs

open

void open()
          throws KuraGPIODeviceException,
                 KuraUnavailableDeviceException,
                 IOException

Opens the pin and allocates the needed resources to communicate with it.

Throws:

KuraGPIODeviceException - when an exception occurs opening the pin

KuraUnavailableDeviceException - when the GPIO resource is not available

IOException - if a generic I/O error occurs

close

void close()
           throws IOException

Closes this pin and deallocates the resources needed to communicate with it.

If there is a PinStatusListener attached to this pin, the implementation should remove it before closing the resource.

Throws:

IOException - if a generic I/O error occurs

getDirection

KuraGPIODirection getDirection()

Returns:

KuraGPIOPinDirection representing the direction (Input/Output) of the PIN

getMode

KuraGPIOMode getMode()

Returns:

KuraGPIOMode representing the mode of the pun.
Open Drain / Push Pull for outputs, Pull Up / Pull Down for inputs.

getTrigger

KuraGPIOTrigger getTrigger()

Returns:

KuraGPIOTrigger representing the trigger mode for this pin.

getName

String getName()

Returns:

the name associated with the the pin

getIndex

int getIndex()

Returns:

the numeric index of the pin's terminal

isOpen

boolean isOpen()

Returns:

true if the pin has been previously opened for use.