Command Dictionary

Set Loop Handling

 

 

FlexTest uses a gate duplication technique to reduce the impact of the TIEX and DELAY gates that it places to break combinational loops. You can use this command to turn on this feature thereby allowing FlexTest to performing a further analysis to verify whether the inserted TIEX and DELAY gates are necessary.

For another look at combinational feedback loops, refer to “ Feedback Loops” in the Scan and ATPG Process Guide.

Arguments

Tiex

A literal that specifies that TIE-X gates are used to break combinational loops.

Simulation

A literal that specifies for the tool to use a simulation process to stabilize values in the loop. This option gives more accurate simulation results than other options. This is the default.

Delay (FlexTest Only)

A literal that inserts a delay element to break a loop.

-Duplication ON OFf

An optional switch and literal pair that specify whether the tool can insert duplicate gates to reduce the impact of the gates that the tool places to break combinational loops. The literal choices are as follows:

oON — An optional literal that specifies for the circuit learning process to generate duplicate gates within any identified feedback paths.

oOFf — An optional literal that specifies for the circuit learning process to not generate duplicate gates within any identified feedback paths. This is the default upon invocation.

FlexTest — If this option is selected, FlexTest does no further analysis to verify whether the inserted TIEX and DELAY gates are necessary. Because some combinational loops are functionally incapable of actually behaving as a loop, you can eliminate those unnecessary TIEX and DELAY gates that FlexTest would have inserted.

FastScan and FlexTest Reference Manual, V8.6_4

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Mentor v8.6_4 manual ∙ Tiex, ∙ Simulation, ∙ Delay FlexTest Only