Mentor v8.6_4 manual ∙ passesinteger, ∙ -ResetauFastScan Only, ∙ -ForceFlexTest Only

Compress Patterns Command Dictionary

FlexTest Self-Initialized Specifics

You may only use the Compress Patterns command for combinational circuits or scan circuits. For scan circuits, FlexTest assumes all the non-scan cells will not hold their values during loading. By default, FlexTest does not allow pattern compression for scan circuits that contain any non-scan cells having Hold capability during scan operation. This is because the results may change due to the reordering of the test patterns causing reduced fault coverage. You can override the default by using the -Force option to compress these patterns, but the results may change. You should understand the impact of this option when deciding whether or not to use this option.

The Compress Patterns command has a residual memory effect. The initial mode (reverse/random) is not fixed. Instead, it toggles back and forth, starting with the mode last used in the same run. You must quit and restart FlexTest to begin with the same compaction mode.

Arguments

∙passes_integer

An optional integer that specifies the number of pattern compression passes. The default is 1 (perform a single compression pass only).

∙-Reset_au(FastScan Only)

An optional switch that specifies fault simulation of AU faults.

∙-Force(FlexTest Only)

An optional switch that specifies pattern compression for scan circuits which contain any non-scan cells that have Hold capability during scan operation.

∙-MAx_useless_passes integer

An optional switch and integer pair that specifies the maximum number of consecutive useless (no eliminated patterns) passes the tool allows before terminating the pattern compression process. This command option has no effect on the pattern set if the number of passes (passes_integer argument) is smaller than the integer value of this switch. The default is the passes_integer value.

2-150 FastScan and FlexTest Reference Manual, V8.6_4