FastScan and FlexTest Reference Manual, V8.6_4
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Analyze Control Command Dictionary
Analyze Control
Tools Supported: FastScan
Scope: Atpg, Fault, and Good modes
Usage
ANAlyze COntrol
Description
Calculates zero and one-state controllability.
The Analyze Control command calculates the zero and one–state controllability
by performing good circuit simulation for all gates in the design. Controllability
coverage (either one or zero) is a measure of the percentage of times a gate can
achieve a zero or one state for a set number of random patterns. You set the
number of applied random patterns with the Set Random Patterns command.
Gates should attain both zero and one states a reasonable number of times (the
control threshold), which you determine and set with the Set Control Threshold
command.
After issuing the Analyze Control command, you can display detailed information
about individual gates by using the Report Control Data command. This
information helps you identify circuit points that can increase the design’s
controllability. You can then evaluate the effects of making these points control
points by using the Add Control Points command and then reissuing the Analyze
Control command.
You use this command primarily for developing Built-In Self Test (BIST)
circuitry.
Examples
The following example calculates the controllable test coverage from gate values
which fail to achieve a state of minimum number of patterns:
set system mode atpg
set random patterns 612
set control threshold 5
analyze control
report control data