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. 10, 2001
Filed:
Aug. 06, 1997
Keitaro Ado, Hyogo, JP;
Isamu Moriwaki, Osaka, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A data processing apparatus of an optical disk drive includes a buffer memory which has a page area divided into a plurality of pages, each page having a predetermined size and containing a main data, a subcode and an error code within the page, each page corresponding to one sector of digital data produced by the disk drive with respect to a compact digital disk, an address of each page of the buffer memory being specified by a page number. A buffer management unit accesses data of a particular page of the buffer memory in response to an input address, the input address specifying a starting address of the data of the particular page of the buffer memory. A system control unit having a page register generates the input address by combining a page number stored by the page register with a predetermined offset, and supplies the input address to the buffer management unit when the data of the buffer memory is accessed, the offset being determined in accordance with the data to be accessed, the page number specifying a starting address of the particular page of the buffer memory, the offset specifying a location of the data to be accessed in the particular page relative to the starting address.