The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 30, 1996
Filed:
May. 25, 1994
Applicant:
Inventor:
Thomas W Savage, San Jose, CA (US);
Assignee:
Tandem Computers, Incorporated, Cupertino, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
371 223 ; 371 492 ; 371 53 ; 371 572 ;
Abstract
A boundary scan bus error reporting circuitry loads an unused sentinel bit pattern into the boundary scan instruction register in a conventional error reporting boundary scan test system. The unused sentinel bit pattern signifies that a fault exists somewhere upstream of the instruction register in the boundary scan circuitry associated with a specific integrated circuit. The special sentinel pattern is loaded into the instruction register in response to an illegal instruction control signal generated by an instruction decoder coupled to the instruction latch in the boundary scan architecture.