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:
Feb. 01, 2005
Filed:
May. 20, 2002
Fumihiko Akahane, Nagano, JP;
Tsutomu Baba, Nagano, JP;
Fumihiko Akahane, Nagano, JP;
Tsutomu Baba, Nagano, JP;
Sankyo Seiki Mfg. Co., Ltd., Nagano, JP;
Abstract
In a nonvolatile memory such as flash memory where data is stored sector by sector, a method of overwriting a data sector is provided. The old data to be overwritten in a data sector along with its error detection code are initially saved to a backup region which is also in a non-volatile area. The old data in the data sector is then erased and new data along with its own error detection code are written into the same data sector where the old data was previously stored. When a power outage occurs during the overwrite process, error checking is performed to determine whether the data in the data sector is valid using the associated error detection code. Because the old data is saved in a non-volatile area, even if such unexpected power outage occurs during the overwrite process and the data in the data sector is determined to be invalid, at least the old data can be recovered from the non-volatile backup region which is not affected by the power outage.