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:
Aug. 25, 1998
Filed:
Aug. 02, 1996
Hiroshi Imai, Tokyo, JP;
Tasuku Kasebayashi, Tokyo, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
Test data are written into all password data areas SDAs located on each of surfaces of a disk arranged in a disk drive apparatus. SDAs each having a low error rate are selected. A predetermined number of SDAs dispersed on the plural disk surfaces are selected as effective SDAs from the selected SDAs. Position data of these effective SDAs are registered in an EEPROM. A password is written into each of the effective SDAs in a low error rate order and the disk drive apparatus is set to a locked state. A password input by a user is compared with the password written into each of the effective SDAs to release the locked state. Therefore, when an unlock command is input, the password is read from each of the effective SDAs in the writing sequential order of the password. When the password is correctly read, the read password is compared with the password input by the user. The locked state is released only when these passwords coincide with each other.