Mentor v8.6_4 manual Add LFSRs, ∙ Prpg, ∙ Misr, ∙ length

Add LFSRs Command Dictionary

Add LFSRs

Tools Supported: FastScan

Scope: Setup mode

Usage

ADD LFsrs lfsr_name {Prpg Misr} length seed [-Both -Serial -Parallel] [-Out -In]

Description

Adds Linear Feedback Shift Registers (LFSRs) for use as Pseudo-Random Pattern Generators (PRPGs) or Multiple Input Signature Registers (MISRs).

The Add LFSRs command defines LFSRs, which FastScan uses as PRPGs, to create pseudo-random values for the Built-In Self Test (BIST) patterns or as MISRs to compact responses.

You specify the LFSR’s shift technique by using one of the following shift_type switches: -Both, -Serial, or -Parallel. You specify the placement of the exclusive- OR taps by using one of the following tap_type switches: -Out or -In. You can change the default setting of the shift_type and tap_type switches by using the Setup LFSRs command.

You use this command primarily for simulating Built-In Self Test (BIST) circuitry.

Arguments

∙lfsr_name

A required string that specifies the name that you want to assign to the LFSR.

∙Prpg

A literal that indicates the LFSR functions as a PRPG.

∙Misr

A literal that indicates the LFSR functions as a MISR.

∙length

A required integer, greater than 1, specifying the number of bits in the LFSR.

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