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:
Sep. 22, 1998
Filed:
Dec. 02, 1996
Philip A Murphy, King of Prussia, PA (US);
Timothy D Updegrove, Birdsboro, PA (US);
John A Keller, Coatesville, PA (US);
Unisys Corporation, Blue Bell, PA (US);
Abstract
A system and method are disclosed for providing computers, particularly the Unisys A series computers, with the capability to function with disk drives of more than one sector format, especially if a predetermined sector format is inefficient and/or cost prohibitive. Interfacing is provided for processing I/O requests between a predetermined logical sector format (e.g., 180 byte sectors) and a variable physical sector format (e.g., 512 or 720 byte sectors). Read operations compare read request addresses to physical sector boundaries and discard unwanted data. Write operations, using at least one sector buffer, perform a read/modify/write cycle, such that the necessary physical sector data not associated with the write request is read into the sector buffer, modified and written back to the disk along with the write data inserted at the appropriate location. This system and method can effectively increase the usable capacity of selected disk drives by 15-20%.