ptolemy.actor.lib.vhdl
Class RegisterSR

java.lang.Object
  extended by ptolemy.kernel.util.NamedObj
      extended by ptolemy.kernel.InstantiableNamedObj
          extended by ptolemy.kernel.Entity
              extended by ptolemy.kernel.ComponentEntity
                  extended by ptolemy.actor.AtomicActor
                      extended by ptolemy.actor.TypedAtomicActor
                          extended by ptolemy.actor.lib.vhdl.FixTransformer
                              extended by ptolemy.actor.lib.vhdl.SynchronousFixTransformer
                                  extended by ptolemy.actor.lib.vhdl.RegisterSR
All Implemented Interfaces:
java.io.Serializable, java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, TypedActor, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

public class RegisterSR
extends SynchronousFixTransformer

This actor provides a one-tick delay. On each firing, it produces on the output port whatever value it read on the input port in the previous tick of the clock. If the input was absent on the previous tick of the clock, then the output will be absent. On the first tick, the output is initialValue if it is given, and absent otherwise. In contrast to the Pre actor, this actor is non-strict, and hence can break causality loops. Whereas Pre provides a one-step delay of non-absent values, this actor simply delays by one clock tick.

Since:
Ptolemy II 2.0
Version:
$Id: RegisterSR.java 57040 2010-01-27 20:52:32Z cxh $
Author:
Paul Whitaker, Elaine Cheong, and Edward A. Lee
See Also:
Pre, SampleDelay, TimedDelay, Serialized Form
Accepted Rating:
Yellow (cxh)
Proposed Rating:
Yellow (celaine)

Nested Class Summary
 
Nested classes/interfaces inherited from class ptolemy.kernel.Entity
Entity.ContainedObjectsIterator
 
Field Summary
 TypedIOPort input
          The input port.
 
Fields inherited from class ptolemy.actor.lib.vhdl.SynchronousFixTransformer
initialValue, latency
 
Fields inherited from class ptolemy.actor.lib.vhdl.FixTransformer
output
 
Fields inherited from class ptolemy.actor.AtomicActor
_actorFiringListeners, _initializables, _notifyingActorFiring, _stopRequested
 
Fields inherited from class ptolemy.kernel.util.NamedObj
_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS
 
Fields inherited from interface ptolemy.actor.Executable
COMPLETED, NOT_READY, STOP_ITERATING
 
Constructor Summary
RegisterSR(CompositeEntity container, java.lang.String name)
          Construct an actor in the specified container with the specified name.
 
Method Summary
 void fire()
          If the input known and there is a token on the input port, consume the token from the input port, and store it for output on the next iteration.
 void preinitialize()
          Override the base class to declare that the input port does not depend on the output in a firing.
 
Methods inherited from class ptolemy.actor.lib.vhdl.SynchronousFixTransformer
attributeChanged, initialize, isStrict
 
Methods inherited from class ptolemy.actor.lib.vhdl.FixTransformer
_checkFixMaxValue, _checkFixTokenWidth, _setAndHideQuantizationParameters, _setQuantizationParameters, _showQuantizationParameters, getPortPrecision, newFixOutputPort, sendOutput
 
Methods inherited from class ptolemy.actor.TypedAtomicActor
_addPort, _fireAt, _fireAt, attributeTypeChanged, clone, newPort, typeConstraintList, typeConstraints
 
Methods inherited from class ptolemy.actor.AtomicActor
_actorFiring, _actorFiring, addActorFiringListener, addInitializable, clone, connectionsChanged, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, isFireFunctional, iterate, newReceiver, outputPortList, postfire, prefire, pruneDependencies, recordFiring, removeActorFiringListener, removeDependency, removeInitializable, setContainer, stop, stopFire, terminate, wrapup
 
Methods inherited from class ptolemy.kernel.ComponentEntity
_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName
 
Methods inherited from class ptolemy.kernel.Entity
_description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName
 
Methods inherited from class ptolemy.kernel.InstantiableNamedObj
_setParent, exportMoML, getChildren, getElementName, getParent, getPrototypeList, isClassDefinition, isWithinClassDefinition
 
Methods inherited from class ptolemy.kernel.util.NamedObj
_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _debug, _debug, _debug, _debug, _debug, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _propagateValue, _recordDecoratedAttributes, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, attributeList, attributeList, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttributes, getChangeListeners, getClassName, getDecoratorAttribute, getDecoratorAttributes, getDerivedLevel, getDerivedList, getDisplayName, getFullName, getModelErrorHandler, getName, getName, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, lazyContainedObjectsIterator, message, propagateValue, propagateValues, removeChangeListener, removeDebugListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, validateSettables, workspace
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface ptolemy.actor.Actor
createReceivers, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, newReceiver, outputPortList
 
Methods inherited from interface ptolemy.actor.Executable
isFireFunctional, iterate, postfire, prefire, stop, stopFire, terminate
 
Methods inherited from interface ptolemy.actor.Initializable
addInitializable, removeInitializable, wrapup
 
Methods inherited from interface ptolemy.kernel.util.Nameable
description, getContainer, getDisplayName, getFullName, getName, getName, setName
 
Methods inherited from interface ptolemy.kernel.util.Derivable
getDerivedLevel, getDerivedList, propagateValue
 

Field Detail

input

public TypedIOPort input
The input port. The default type is Fix.

Constructor Detail

RegisterSR

public RegisterSR(CompositeEntity container,
                  java.lang.String name)
           throws IllegalActionException,
                  NameDuplicationException
Construct an actor in the specified container with the specified name.

Parameters:
container - The container.
name - The name of this actor within the container.
Throws:
IllegalActionException - If the actor cannot be contained by the proposed container.
NameDuplicationException - If the name coincides with an actor already in the container.
Method Detail

fire

public void fire()
          throws IllegalActionException
If the input known and there is a token on the input port, consume the token from the input port, and store it for output on the next iteration. Otherwise, store an AbsentToken for output on the next iteration. If a token was received on the previous iteration, output it to the receivers. Otherwise, notify the receivers that there will never be any token available in the current iteration.

Specified by:
fire in interface Executable
Overrides:
fire in class AtomicActor
Throws:
IllegalActionException - If there is no director.

preinitialize

public void preinitialize()
                   throws IllegalActionException
Override the base class to declare that the input port does not depend on the output in a firing.

Specified by:
preinitialize in interface Initializable
Overrides:
preinitialize in class SynchronousFixTransformer
Throws:
IllegalActionException - Not thrown in this base class.