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:
Jun. 30, 1987
Filed:
Aug. 15, 1984
Mikito Ogata, Odawara, JP;
Masahito Mori, Odawara, JP;
Takashi Doi, Hadano, JP;
Michio Miyazaki, Odawara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A data recording/reproducing method for a non-rewritable recording medium of a rotating type, each of tracks on the recording medium is divided into a plurality of blocks which are allotted with respective addresses. Each block includes a data recording area and a deletion flag area which is divided into a plurality of sub-areas. One of the sub-areas in a given block is associated with other block which is in a predetermined address relation with the given block. When the content in the data recording area of one block on the recording medium is to be rendered invalid, deletion flag information is also recorded in the sub-area of the other block having the predetermined address relation with the one block. Upon reading, the data of the blocks read out from the recording medium exclusive of the data of the block determined to be invalid on the basis of the flag information is transferred to a high-rank system.