Mentor v8.6_4 manual Set Xclock Handling, ∙ Retain

Set Xclock Handling Command Dictionary

Set Xclock Handling

Tools Supported: FastScan

Scope: All modes

Usage

SET XCLock Handling Retain X

Description

Specifies whether FastScan changes the sequential element model to always set the output of the element to be X when any of its clock inputs become X.

Upon invocation, FastScan uses the default flip-flop and latch models for sequential elements. These default models retain their output values when their clock value becomes X, so long as the other input values do not cause the stored output value to change, regardless of whether the clock was at a 0 or 1. The Set Xclock Handling command allows you to override this behavior during parallel pattern simulation, thereby causing the stored output value to become X.

This command will have no effect during DRC simulation. FastScan uses the default flip-flop and latch behavior during DRC simulation.

Arguments

∙Retain

A required literal specifying that FastScan use the default sequential element model. This is the default upon FastScan invocation.

∙X

A required literal specifying that FastScan change the sequential element model so that during parallel pattern simulation the output of the element is set to X when any of its clock inputs become X.

2-598 FastScan and FlexTest Reference Manual, V8.6_4