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TEMPORAL OPERATORS 2

Detach



A detached temporal expression is evaluated independently of the expression in which it is used. It starts evaluation when the main expression does. Whenever the detached TE succeeds it emits an ‚~@~\implicit‚~@~] event which will only be recognized by the main TE. The detached temporal expression inherits the sampling event from the main temporal expression.



Delay



Succeeds after a specified simulation time delay elapses. A callback to Specman Elite occurs after the specified time. A delay of zero succeeds immediately.
Attaching a sampling event to delay has no effect. The delay ignores the sampling event and succeeds as soon as the delay period elapses.



@ Unary Event Operator



An event can be used as the simplest form of a temporal expression. The temporal expression @event-type succeeds every time the event occurs. Success of the expression is simultaneous with the occurrence of the event. The struct-exp is an expression that evaluates to the struct instance that contains the event instance. If no struct expression is specified, the default is the current struct instance.



@ Sampling Operator



Used to specify the sampling event for a temporal expression. The specified sampling event overrides the default sampling event. Every temporal expression has a sampling event. The sampling event applies to all subexpressions of the temporal expression. It can be overridden for a subexpression by attaching a different sampling event to the subexpression. A sampled temporal expression succeeds when its sampling event occurs with or after the success of the temporal expression.



Cycle



Represents one cycle of some sampling event.With no explicit sampling event specified, this represents one cycle of the default sampling event. With a sampling event specified, cycle is equivalent to @sys.any@sampling-event.



True(Exp)



Use a Boolean expression as a temporal expression. Each occurrence of the sampling event causes an evaluation of the Boolean expression. The Boolean expression is evaluated only at the sampling point. The temporal expression succeeds each time the expression evaluates to TRUE.



Change(Exp), Fall(Exp), Rise(Exp)



Detects a change in the sampled value of an expression.



Consume



Removes the occurrence of an event so that it is not available for other temporal expressions. The consume expression succeeds whenever the event occurs. If the event occurs more than once during any given cycle, all occurrences are consumed. After an event occurrence is consumed, that occurrence will not be recognized by any temporal expression during the current Specman Elite tick, unless the event is emitted again. An event cannot be consumed by more then one consume expression. Care should be used to avoid creating race conditions between multiple events that use an event that is consumed.



Exec



Invokes an action block when a temporal expression succeeds. The actions are executed immediately upon the success of the expression, but not more than once per Specman Elite tick.


Index
Introduction
E Basics
Data Types
Operators
Struct
Units
List
Methods
Concurrency Actions
Constraints
Extend
When And Like
Events
Temporal Expressions
Temporal Operators 1
Temporal Operators 2
Synchronizing With The Simulator
Wait And Sync
Physical Virual Feilds
Packing N Unpacking
Pre Run N On The Fly
Coverage
Commands
Extendable Methods
Non Extendable Methods
And Gate Evc

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