Module com.pi4j

Package com.pi4j.io.gpio.digital

Class DigitalOutputBase

java.lang.Object

com.pi4j.common.IdentityBase

com.pi4j.io.IOBase<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>

com.pi4j.io.gpio.GpioBase<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>

com.pi4j.io.gpio.digital.DigitalBase<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>

com.pi4j.io.gpio.digital.DigitalOutputBase

All Implemented Interfaces:

Describable, Identity, Lifecycle, Extension, Bindable<DigitalOutput,DigitalBinding>, Digital<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>, DigitalOutput, com.pi4j.io.gpio.Gpio<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>, IO<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>, OnOff<DigitalOutput>, OnOffRead<DigitalOutput>, OnOffWrite<DigitalOutput>, Output

public abstract class DigitalOutputBase
extends DigitalBase<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>
implements DigitalOutput

Abstract DigitalOutputBase class.

Version:

$Id: $Id

Author:

Robert Savage (http://www.savagehomeautomation.com)

Field Summary

Fields

Modifier and Type	Field	Description
protected DigitalState	state

Fields inherited from class com.pi4j.io.gpio.digital.DigitalBase

bindings, stateChangeEventManager

Fields inherited from class com.pi4j.io.IOBase

config, provider

Fields inherited from class com.pi4j.common.IdentityBase

description, id, logger, metadata, name

Constructor Summary

Constructors

Constructor	Description
DigitalOutputBase(DigitalOutputProvider provider, DigitalOutputConfig config)	Constructor for DigitalOutputBase.

Method Summary

Modifier and Type	Method	Description
DigitalOutput	blink(int delay, int duration, TimeUnit unit, DigitalState state, Callable<Void> callback)	This method will blink an output pin of the RPi according the given specifications.
Future<?>	blinkAsync(int delay, int duration, TimeUnit unit, DigitalState state, Callable<Void> callback)	This method is exactly the same as the blink() method, except that this method is non-blocking and returns a Future with which the action can be cancelled, or it can be detected if the task is complete
DigitalOutput	initialize(Context context)	initialize.
DigitalOutput	off()
DigitalOutput	on()
DigitalOutput	pulse(int interval, TimeUnit unit, DigitalState state, Callable<Void> callback)	pulse.
Future<?>	pulseAsync(int interval, TimeUnit unit, DigitalState state, Callable<Void> callback)	pulseAsync.
DigitalOutput	shutdown(Context context)	shutdown.
DigitalState	state()	state.
DigitalOutput	state(DigitalState state)	state.

Methods inherited from class com.pi4j.io.gpio.digital.DigitalBase

addListener, bind, dispatch, isOn, removeListener, unbind

Methods inherited from class com.pi4j.io.gpio.GpioBase

toString

Methods inherited from class com.pi4j.io.IOBase

config, context, describe, description, name, provider

Methods inherited from class com.pi4j.common.IdentityBase

description, id, metadata, name

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.pi4j.io.binding.Bindable

bind, unbind

Methods inherited from interface com.pi4j.io.gpio.digital.Digital

addListener, equals, equals, equals, equals, equals, equals, equals, equals, equals, isHigh, isLow, removeListener

Methods inherited from interface com.pi4j.io.gpio.digital.DigitalOutput

blink, blink, blink, blinkAsync, blinkAsync, blinkAsync, high, low, pulse, pulse, pulseAsync, pulseAsync, pulseHigh, pulseHighAsync, pulseLow, pulseLowAsync, setState, setState, setState, setState, setState, setState, setState, toggle

Methods inherited from interface com.pi4j.io.gpio.Gpio

address, getAddress

Methods inherited from interface com.pi4j.common.Identity

description, getDescription, getId, getMetadata, getName, id, metadata, name

Methods inherited from interface com.pi4j.io.IO

config, description, name, provider, type

Methods inherited from interface com.pi4j.io.OnOffRead

isOff, isOn

Field Details

state

protected DigitalState state

Constructor Details

DigitalOutputBase

public DigitalOutputBase(DigitalOutputProvider provider,
 DigitalOutputConfig config)

Constructor for DigitalOutputBase.

Parameters:

provider - a DigitalOutputProvider object.

config - a DigitalOutputConfig object.

Method Details

initialize

public DigitalOutput initialize(Context context)
                         throws InitializeException

initialize.

Specified by:

initialize in interface Lifecycle

Overrides:

initialize in class IOBase<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>

Parameters:

context - a Context object.

Returns:

a T object.

Throws:

InitializeException - if an error occurs during initialization.

state

public DigitalOutput state(DigitalState state)
                    throws IOException

state.

Specified by:

state in interface DigitalOutput

Parameters:

state - a DigitalState object.

Returns:

a DigitalOutput object.

Throws:

IOException - if any.

pulse

public DigitalOutput pulse(int interval,
 TimeUnit unit,
 DigitalState state,
 Callable<Void> callback)
                    throws IOException

pulse.

Specified by:

pulse in interface DigitalOutput

Parameters:

interval - a int.

unit - a TimeUnit object.

state - a DigitalState object.

callback - a Callable object.

Returns:

a DigitalOutput object.

Throws:

IOException - if any.

pulseAsync

public Future<?> pulseAsync(int interval,
 TimeUnit unit,
 DigitalState state,
 Callable<Void> callback)

pulseAsync.

Specified by:

pulseAsync in interface DigitalOutput

Parameters:

interval - a int.

unit - a TimeUnit object.

state - a DigitalState object.

callback - a Callable object.

Returns:

a Future object.

blink

public DigitalOutput blink(int delay,
 int duration,
 TimeUnit unit,
 DigitalState state,
 Callable<Void> callback)

This method will blink an output pin of the RPi according the given specifications. The pin itself is created while creating a DigitalOutput configuration where one of the parameters is an address (= a BCM pin number).

Specified by:

blink in interface DigitalOutput

Parameters:

delay - The toggle time.

duration - The amount of times the output has to toggle.

Representation:

   Output HIGH +-----+     +-----+     +-----+     +-----+     +-----+
               |     |     |     |     |     |     |     |     |     |
   Output LOW  +     +-----+     +-----+     +-----+     +-----+     +-----+
               ^                                                           ^
        start -┘                                                           └- stop
                \___/ \___/
                delay  delay

               \___________________________________________________________/
                                        duration
 

Example:

Delay = 1 sec / duration = 5
Output will be like so (suppose the initial state is set to HIGH):
1 - 0 - 1 - 0 - 1 - 0 - 1 - 0 - 1 - 0 with each state lasting for 1 second.
So, if you would connect a LED to the pin, you would see the LED switching
on and off for 5 times.

Note: this is a blocking method!
For as long as it takes to manipulate the output pin, the method will not return.

In the example given above, it means the method will block for 10 seconds (5 times high for a second
and 5 times low for a second), also for calling the callback function.

If you don't want the blink() method to block the calling thread, pls. use the blinkAsync() method instead.

unit - The time unit used to calculate the delay.

state - The initial state of the pin.

callback - The method to call, if any, once the blinking is done.

Returns:

The DigitalOutputBase object itself.

blinkAsync

public Future<?> blinkAsync(int delay,
 int duration,
 TimeUnit unit,
 DigitalState state,
 Callable<Void> callback)

This method is exactly the same as the blink() method, except that this method is non-blocking and returns a Future with which the action can be cancelled, or it can be detected if the task is complete

See the blink() method for a more detailed explanation on how the method works.

Specified by:

blinkAsync in interface DigitalOutput

Parameters:

delay - The toggle time.

duration - The amount of times the output has to toggle.

unit - The time unit used to calculate the delay.

state - The initial state of the pin.

callback - The method to call, if any, once the blinking is done.

Returns:

A Future object that can be used to observe the end of the async blinking.

state

public DigitalState state()

state.

Specified by:

state in interface Digital<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>

Returns:

a DigitalState object.

shutdown

public DigitalOutput shutdown(Context context)
                       throws ShutdownException

shutdown.

Specified by:

shutdown in interface Lifecycle

Overrides:

shutdown in class DigitalBase<DigitalOutput,DigitalOutputConfig,DigitalOutputProvider>

Parameters:

context - a Context object.

Returns:

a T object.

Throws:

ShutdownException - if an error occurs during shutdown.

on

public DigitalOutput on()
                 throws IOException

Specified by:

on in interface OnOffWrite<DigitalOutput>

Throws:

IOException

off

public DigitalOutput off()
                  throws IOException

Specified by:

off in interface OnOffWrite<DigitalOutput>

Throws:

IOException