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:
Mar. 17, 1992
Filed:
Dec. 14, 1989
Naoki Yamauchi, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor integrated circuit with a non-volatile memory capable of electric rewriting of data is disclosed. The circuit is provided with inhibiting means for comparing an address of a write inhibition area of the non-volatile memory and an address from an external or internal CPU and inhibiting the writing of data in the area when the two compared addresses coincide, and also comparing an address of a read inhibition area of the non-volatile memory and an address from an external reader/writer and inhibiting the reading of data from the area when the two compared addresses coincide. It is thus possible to prevent erroneous rewriting of a program or protection-required data due to runaway of CPU and also prevent reading of secret data by a third party. Thus, a microcomputer can be realized, in which a program memory and a data memory both consist of non-volatile memories capable of rewriting of data, and which is very easy to use and has improved reliability and confidential property.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile