16.8.3 Sampled value functions

REPLACE

This subclause describes the system functions available for accessing sampled values of an expression.These functions include the capability to access current sampled value, access sampled value in the past, or detect changes in sampled value of an expression. Sampling of an expression is explained in 16.4. The sequence methods ended, triggered, and matched cannot be used as arguments to these functions. The following functions are provided:

$sampled(expression [, clocking_event])

$rose( expression [, clocking_event])

$fell( expression [, clocking_event])

$stable( expression [, clocking_event])

$past( expression1 [, number_of_ticks] [, expression2] [, clocking_event])

WITH

This subclause describes the system functions available for accessing sampled values of an expression.These functions include the capability to access current sampled value, access sampled value in the past, or detect changes in sampled value of an expression. Sampling of an expression is explained in 16.4. The sequence methods ended, triggered, and matched cannot be used as arguments to these functions. The following functions are provided:

$sampled(expression [, [clocking_event]])

$rose( expression [,[clocking_event]])

$fell( expression [,[clocking_event]])

$stable( expression [,[clocking_event]])

$past( expression1 [,[number_of_ticks] [,[expression2] [,[clocking_event] ] ]])

19.11 Assertion system functions

REPLACE

A function is provided to return sampled value of an expression.

$sampled ( expression [, clocking_event] )

Three functions are provided for assertions to detect changes in values between two adjacent clock ticks.

$rose ( expression [, clocking_event] )

$fell ( expression [, clocking_event] )

$stable ( expression [, clocking_event] )

The past values can be accessed with the $past function.

$past ( expression [, number_of_ticks] [, expression2] [, clocking_event] )

Functions $sampled, $rose, $fell, $stable, and $past are discussed in 16.8.3.

WITH

A function is provided to return sampled value of an expression.

$sampled ( expression [,[clocking_event]] )

Three functions are provided for assertions to detect changes in values between two adjacent clock ticks.

$rose ( expression [,[clocking_event]] )

$fell ( expression [,[clocking_event]] )

$stable ( expression [,[clocking_event]] )

The past values can be accessed with the $past function.

$past ( expression [,[number_of_ticks] [,[expression2] [,[clocking_event]]]] )

Functions $sampled, $rose, $fell, $stable, and $past are discussed in 16.8.3.