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. 07, 1989
Filed:
Apr. 15, 1986
Erich Knothe, Eddigehausen, DE;
Franz-Josef Melcher, Hardegsen, DE;
Sartorius GmbH, , DE;
Abstract
Method and apparatus of storing data in an electrically erasable memory connected to a microprocessor to effectively protect data stored in the memory from being unintentionally overwritten in cases of defective operation of the microprocessor, an overwrite protection system consisting of a write protect flip-flop (1) whose two logical states signify 'with write protection' and 'without write protction' and also a gate (3) in the write line which is controlled by the write protect flip-flop and in whose logical 'with write protection' state, write errors are prevented from being conducted to the individual memory locations, and, finally a mechanical switch element (5) whereby these components are connected in such a manner that the write protect flip-flop (1) can only be brought into the one logical 'with write protection' state by the microprocessor, while it can only be brought into the other logical 'without write protection' state, if and when the mechanical switch element (5) is actuated. The overwrite protection can apply depending on the embodiment to the entire electronically erasable memory or only to the subareas thereof.