Being the control unit which is loaded onto the program null USB storage device in order to make the USB storage device

摘要

PPROBLEM TO BE SOLVED: To provide a USB storage device having the function of preventing the wrong erasing of stored software, the function being realized with a simple structure as much as possible. PSOLUTION: In this device, a storage area is divided to an area where read, write and deletion of data are executable and an area where only the read is executable, and information for making a USB mass storage class driver possessed by a host recognize these areas as areas corresponding to logic unit numbers defined in the SCSI command set of the USB mass-storage class driver is retained. This information is formed of a logic number unit 31, a format 33, a writable/deletable flag 35, a logic block number 37, and a physical block number 39. Consequently, the USB mass storage class driver recognizes the USB storage device as one SCSI device having two logic units. PCOPYRIGHT: (C)2006,JPO&NCIPI