Jeffrey Alan Techau

54523095, Sep 19, 1995

Dec 18, 1992

7/993136

David T. Ino - Santa Clara CA
Patricia A. Simonson - San Jose CA
Jeffrey A. Techau - Sunnyvale CA
Richard H. Larson - Los Gatos CA

Amdahl Corporation - Sunnyvale CA

G01R 3128

371 223

An apparatus and method for forcing stuck-at and transient errors at sequential and combinational logic and signal lines in a large scale data processing system. Error forcing is achieved by including a scan-in gate with error input and address lines for each scan point to be tested. A fault signal of adjustable duration is generated and combined in a unique fashion to an existing scan-in signal to permit either stuck-at or transient errors to be forced.

52710190, Dec 14, 1993

Mar 15, 1991

7/670289

Robert Edwards - San Jose CA
Jeffrey Techau - Sunnyvale CA
Rita Rudolph - Sunnyvale CA

Amdahl Corporation - Sunnyvale CA

G01R 31318

371 223

A set of scan latches is partitioned into unique groups where each group is addressable by a group initializing circuit. The group initializing circuit initializes all the latches of an addressed group to a predefined state thereby quickly loading a test vector into the addressed group of scan latches while leaving other latches undisturbed.