ch.eitchnet.beaglebone

Interface GpioBridge

All Known Implementing Classes:

GpioBridgeImpl

public interface GpioBridge

Method Summary

Modifier and Type	Method and Description
Gpio	getGpio(Pin pin, Direction direction) Returns the Gpio for the given Direction.
Signal	readValue(Gpio gpio) Public API method to read the current Signal on the given Gpio's pin.
void	register(Gpio gpio, GpioSignalListener listener) Registers the given GpioSignalListener for changes to Signals on the given Gpio
void	start() Starts the GpioBridge's signal observing Thread.
void	stop() Stops observing any pins and stops the Thread
boolean	unregister(GpioBridgeTest gpio, GpioSignalListener listener) Unregisters a GpioSignalListener from changes to the given Gpio
void	writeValue(Gpio gpio, Signal signal) Public API method to write the given Signal on the given Gpio's pin.

Method Detail

writeValue

void writeValue(Gpio gpio,
                Signal signal)
         throws GpioException

Public API method to write the given Signal on the given Gpio's pin.

Parameters:

gpio - the Gpio to which the Signal should be written

signal - the Signal to write to the given Gpio

Throws:

GpioException - if the direction of the Gpio is not Direction.OUT, or if something goes wrong while writing to the file

readValue

Signal readValue(Gpio gpio)
          throws GpioException

Public API method to read the current Signal on the given Gpio's pin.

Parameters:

gpio - the Gpio for which the Signal should be read

Returns:

The Gpio's current signal

Throws:

GpioException - if the direction of the Gpio is not Direction.IN, or if something goes wrong while reading from the file

start

void start()

Starts the GpioBridge's signal observing Thread. If no observers are registered with the register(Gpio, GpioSignalListener)-method, then this method needs not to be called.

stop

void stop()

Stops observing any pins and stops the Thread

getGpio

Gpio getGpio(Pin pin,
             Direction direction)
      throws GpioException

Returns the Gpio for the given Direction.

Note: This method can not be called multiple times with different Directions. The GpioBridge does not handle pins that are simultaneously input and output as this is not supported by the Linux kernel.

Parameters:

pin - The Pin for which the Gpio in the given Direction is to be returned

direction - the Direction for which this Gpio is to be returned

Returns:

The Gpio with the configured Direction

Throws:

GpioException - If the given Direction does not match the kernel's configured direction, or if the file permissions are not set so that the Java process can access the file (read access for input pin, write access for output pin.

register

void register(Gpio gpio,
              GpioSignalListener listener)
       throws GpioException

Registers the given GpioSignalListener for changes to Signals on the given Gpio

Parameters:

gpio - the Gpio being observed

listener - the GpioSignalListener to be notified on changes on the Gpio's Signal

Throws:

GpioException - if the Direction of the Gpio is not Direction.IN

unregister

boolean unregister(GpioBridgeTest gpio,
                   GpioSignalListener listener)

Unregisters a GpioSignalListener from changes to the given Gpio

Parameters:

gpio - the Gpio for which the listener is to be removed

listener - the GpioSignalListener to be removed from changes to the given Gpio

Returns:

true if the listener was unregistered, false if not