Patent ID: 7039754
Filing Date: 2006-05-02
Classification: G06F,G06Q,G07F

Abstract:
1. A removable data storage device, detachably mounted to a host device, comprising a non-volatile semiconductor memory, wherein data recorded thereon is erased as a block of a predetermined data volume, wherein the non-volatile semiconductor memory is divided into a user area and a system area, wherein the user area is internally managed by logical block numbers and by physical block numbers, and wherein file management data is recorded in said user area in accordance with the logical block numbers and the physical block numbers; an interface for inputting/outputting data between the data storage device and said host device; and a controller for controlling file management in the semiconductor memory in response to a command from said host device over said interface, wherein file management is performed using at least one block area, wherein the block area is divided into a plurality of clusters, wherein each cluster is a size equal to 1/n times the size of said block, n being an integer not less than two, wherein parameters for recording said file management data on said user area are stored in a system information storage unit, and wherein said controller records the file management data in the semiconductor memory when supplied with an initialization command from said host device.