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:
Sep. 24, 1996
Filed:
Jan. 11, 1993
Applicant:
Inventors:
Peter Stutz, Hinterkappelen, CH;
Daniel Fl uckiger, Walkringen, CH;
Assignee:
Ascom Autelca AG, Berne, CH;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ; G06F / ; G06F / ;
U.S. Cl.
CPC ...
395490 ; 36446402 ; 364D / ; 3642469 ; 3642466 ; 365195 ; 39518503 ; 39518504 ;
Abstract
A data protection apparatus has chip select logic, a protection circuit and one or more memory devices. The chip select logic is designed so that when protected memory is addressed, more than one selection signal is generated. In this way, a protected memory area may encompass all, or a portion, of one or more memory devices. The additional selection signal is processed by a protection circuit which will interrupt the processor if protected memory is addressed during a write cycle in the absence of a request signal which the processor is programmed to generate just prior to its writing to a protected memory area.