Patents by Inventor Shoichi Hirashita

Shoichi Hirashita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6516401
    Abstract: The present invention provides, at a lower cost, a highly reliable data reading method and data reading apparatus that can improve backward sequential reading performance. The disk drive is provided with a magnetic disk and a control section having an HDC, a RAM, an MPU controlling the operation of the entire HDD, including control of the HDC, a ROM, and an I/F for connecting to an external host device. The control section executes a backward reading detection step that detects backward reading, a step of receiving a command that reads a block of a first length from a first LBA, a step that reads a block of the first length from the first LBA when backward reading is detected, and a step that pre-fetches a second block from a second LBA smaller than the first LBA; when backward reading is detected, upon completion of the reading of data from the disk, the reading of data predicted to be requested by the next command begins immediately.
    Type: Grant
    Filed: April 6, 2001
    Date of Patent: February 4, 2003
    Assignee: International Business Machines Corporation
    Inventors: Ryoji Fukuhisa, Hirofumi Saitoh, Shoichi Hirashita, Minoru Hashimoto
  • Publication number: 20020023194
    Abstract: The present invention provides, at a lower cost, a highly reliable data reading method and data reading apparatus that can improve backward sequential reading performance. The disk drive is provided with a magnetic disk and a control section having an HDC, a RAM, an MPU controlling the operation of the entire HDD, including control of the HDC, a ROM, and an I/F for connecting to an external host device. The control section executes a backward reading detection step that detects backward reading, a step of receiving a command that reads a block of a first length from a first LBA, a step that reads a block of the first length from the first LBA when backward reading is detected, and a step that pre-fetches a second block from a second LBA smaller than the first LBA; when backward reading is detected, upon completion of the reading of data from the disk, the reading of data predicted to be requested by the next command begins immediately.
    Type: Application
    Filed: April 6, 2001
    Publication date: February 21, 2002
    Applicant: International Business Machines Corporation
    Inventors: Ryoji Fukuhisa, Hirofumi Saitoh, Shoichi Hirashita, Minoru Hashimoto
  • Patent number: 6249854
    Abstract: The present invention provides, at a lower cost, a highly reliable data reading method and data reading apparatus that can improve backward sequential reading performance. The disk drive is provided with a magnetic disk and a control section having an HDC, a RAM, an MPU controlling the operation of the entire HDD, including control of the HDC, a ROM, and an I/F for connecting to an external host device. The control section executes a backward reading detection step that detects backward reading, a step of receiving a command that reads a block of a first length from a first LBA, a step that reads a block of the first length from the first LBA when backward reading is detected, and a step that pre-fetches a second block from a second LBA smaller than the first LBA; when backward reading is detected, upon completion of the reading of data from the disk, the reading of data predicted to be requested by the next command begins immediately.
    Type: Grant
    Filed: August 26, 1998
    Date of Patent: June 19, 2001
    Assignee: International Business Machines Corporation
    Inventors: Ryoji Fukuhisa, Hirofumi Saitoh, Shoichi Hirashita, Minoru Hashimoto