Patents by Inventor Tadahisa Kawa

Tadahisa Kawa 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: 8539176
    Abstract: A data storage device accepts queued read and write commands that have deadlines. The queued read and write commands are requests to access the data storage device. The deadlines of the queued read and write commands can be advisory deadlines or mandatory deadlines.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: September 17, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Donald Joseph Molaro, Frank Rui-Feng Chu, Jorge Campello de Souza, Atsushi Kanamaru, Tadahisa Kawa, Damien C. D. Le Moal
  • Patent number: 7664884
    Abstract: Embodiments of the present invention provide a media drive that is intended for reduction in power consumption required for serial communications to/from a host, and a power saving method thereof. In one embodiment, a HDD includes: a cache; a host interface for transferring, to a host, transfer data read out from the cache; a host interface manager that controls the execution of commands so as to generate a transfer unnecessary period during which a command and transfer data need not be exchanged with the host; and a MPU that brings a serial communication part of the host interface into a power save mode during the transfer unnecessary period. The host interface manager determines the optimum data transfer timing of transferring data from the cache to the host on the basis of a transfer rate at which data is transferred to the host, and a read rate at which data is read out from a disk into the cache.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: February 16, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Atsushi Kanamaru, Tadahisa Kawa, Hiromi Kobayashi, Hirofumi Saitoh
  • Publication number: 20100011149
    Abstract: A data storage device accepts queued read and write commands that have deadlines. The queued read and write commands are requests to access the data storage device. The deadlines of the queued read and write commands can be advisory deadlines or mandatory deadlines.
    Type: Application
    Filed: July 8, 2008
    Publication date: January 14, 2010
    Applicant: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Donald Joseph Molaro, Frank Rui-Feng Chu, Jorge Campello de Souza, Atsushi Kanamaru, Tadahisa Kawa, Damien C. D. Le Moal
  • Patent number: 7487392
    Abstract: Data in a nonvolatile memory included in a data storage device is rewritten with higher security. According to one embodiment of the present invention, if an error is included in data stored in a nonvolatile semiconductor memory, the HDD rewrites correct data to the nonvolatile semiconductor memory. In particular, during the execution sequence of a write command, the HDD executes rewrite processing of control data stored in the nonvolatile semiconductor memory. More specifically, data is rewritten during a specified period of time that falls within a period of time starting from a start notification of write-data transfer processing that is sent from the HDD to the host, until a command completion notification. Since there is a very small possibility that the power of the host may be interrupted during this specified period of time, it is possible to securely rewrite data.
    Type: Grant
    Filed: March 23, 2006
    Date of Patent: February 3, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Tadahisa Kawa, Atsushi Kanamaru, Tsuguaki Kowa
  • Patent number: 7373460
    Abstract: Embodiments of the present invention provide a media drive capable of improving command processing performance by, when a plurality of commands is queued, shortening seek time and rotational latency, and also effectively making use of the shortened period of time. In one embodiment, a HDD includes a queue capable of storing a plurality of commands, and a queue manager for optimizing the execution order of the plurality of commands on the basis of whether or not the execution of each command requires access to a medium. The queue manager determines the execution order so that medium access processing of accessing a disk for execution, and data transfer processing of transferring data between the HDD and a host, are executed in parallel with each other. For example, read processing and transfer processing are executed in parallel with each other. The read processing is adaptive to read out a read command, data of which does not exist in the cache, from the disk into the cache.
    Type: Grant
    Filed: November 10, 2005
    Date of Patent: May 13, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hiromi Kobayashi, Hirofumi Saitoh, Takahiro Saito, Tadahisa Kawa, Atsushi Kanamaru
  • Publication number: 20060218437
    Abstract: Data in a nonvolatile memory included in a data storage device is rewritten with higher security. According to one embodiment of the present invention, if an error is included in data stored in a nonvolatile semiconductor memory, the HDD rewrites correct data to the nonvolatile semiconductor memory. In particular, during the execution sequence of a write command, the HDD executes rewrite processing of control data stored in the nonvolatile semiconductor memory. More specifically, data is rewritten during a specified period of time that falls within a period of time starting from a start notification of write-data transfer processing that is sent from the HDD to the host, until a command completion notification. Since there is a very small possibility that the power of the host may be interrupted during this specified period of time, it is possible to securely rewrite data.
    Type: Application
    Filed: March 23, 2006
    Publication date: September 28, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Tadahisa Kawa, Atsushi Kanamaru, Tsuguaki Kowa
  • Publication number: 20060106980
    Abstract: Embodiments of the present invention provide a media drive capable of improving command processing performance by, when a plurality of commands is queued, shortening seek time and rotational latency, and also effectively making use of the shortened period of time. In one embodiment, a HDD includes a queue capable of storing a plurality of commands, and a queue manager for optimizing the execution order of the plurality of commands on the basis of whether or not the execution of each command requires access to a medium. The queue manager determines the execution order so that medium access processing of accessing a disk for execution, and data transfer processing of transferring data between the HDD and a host, are executed in parallel with each other. For example, read processing and transfer processing are executed in parallel with each other. The read processing is adaptive to read out a read command, data of which does not exist in the cache, from the disk into the cache.
    Type: Application
    Filed: November 10, 2005
    Publication date: May 18, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hiromi Kobayashi, Hirofumi Saitoh, Takahiro Saito, Tadahisa Kawa, Atsushi Kanamaru
  • Publication number: 20060101174
    Abstract: Embodiments of the present invention provide a media drive that is intended for reduction in power consumption required for serial communications to/from a host, and a power saving method thereof. In one embodiment, a HDD includes: a cache; a host interface for transferring, to a host, transfer data read out from the cache; a host interface manager that controls the execution of commands so as to generate a transfer unnecessary period during which a command and transfer data need not be exchanged with the host; and a MPU that brings a serial communication part of the host interface into a power save mode during the transfer unnecessary period. The host interface manager determines the optimum data transfer timing of transferring data from the cache to the host on the basis of a transfer rate at which data is transferred to the host, and a read rate at which data is read out from a disk into the cache.
    Type: Application
    Filed: November 4, 2005
    Publication date: May 11, 2006
    Applicant: Hitachi Global Storage Technologies
    Inventors: Atsushi Kanamaru, Tadahisa Kawa, Hiromi Kobayashi, Hirofumi Saitoh