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. 06, 1999
Filed:
Jan. 30, 1996
David L Brown, Miami, FL (US);
Raul A Pombo, Grayslake, IL (US);
Paul J Polansky, Dripping Springs, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A data processor (20) which flexibly encrypts data within different address ranges includes an encryption determination circuit (50) to monitor an address conducted on an internal address bus (22) and when the address is within certain predefined ranges, perform encryption or decryption of address and/or data. For example the encryption determination circuit (50) may be used to selectively enable a data encryption-decryption circuit (60). When the data encryption-decryption circuit (60) is disabled, data conducted on an internal data bus (23) becomes 'cleartext', i.e., non-encrypted. In one embodiment, the data encryption-decryption is performed in partial dependence on the address itself, and the address conducted to the external address bus is itself selectively encrypted as well.