Patents by Inventor Thomas E. Ludwig

Thomas E. Ludwig 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: 9213611
    Abstract: A storage system including a first boot drive configured to store an operating system, one or more data drives configured to store user data, the one or more data drives distinct from the first boot drive, and a controller configured to detect when a second boot drive is added to the storage system, and automatically configure the first boot drive and the second boot drive in a redundant array of independent disks (“RAID”) configuration when the controller detects that the second boot drive is added to the storage system.
    Type: Grant
    Filed: August 26, 2013
    Date of Patent: December 15, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Thomas E. Ludwig, John E. Maroney
  • Patent number: 9122405
    Abstract: The invention relates to an improved RAID initialization method. Prior to operational use, the device undergoes a forced rebuild that supplements the initialization process. Since the RAID device is in a pre-operational condition, the data does not have to be preserved. Thus, the forced rebuild can employ bulk read and write operations using large portions of data. The forced rebuild results in RAID protection data that can be produced more quickly and is more coherent than what is created by quick initialization. Accordingly, embodiments provide a device that is delivered in an initialized state that is safer and more stable for use by the user.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: September 1, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Thomas E. Ludwig, David N. Still, Edwin D. Barnes
  • Publication number: 20150033067
    Abstract: A storage system including a first boot drive configured to store an operating system, one or more data drives configured to store user data, the one or more data drives distinct from the first boot drive, and a controller configured to detect when a second boot drive is added to the storage system, and automatically configure the first boot drive and the second boot drive in a redundant array of independent disks (“RAID”) configuration when the controller detects that the second boot drive is added to the storage system.
    Type: Application
    Filed: August 26, 2013
    Publication date: January 29, 2015
    Applicant: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: THOMAS E. LUDWIG, JOHN E. MARONEY
  • Patent number: 5555381
    Abstract: A computer system includes a microprocessor that is electrically connected to a first synchronous bus operating in synchronism with a first clock signal at a first clock frequency. A second synchronous bus operates in synchronism with a second clock signal at a second clock frequency and provides electrical communication to a number of peripheral devices. An asynchronous bus provides data communication between the first and second synchronous bus using handshaking signals so that the first and second clock signals operate independently of each other. The operating frequency and other parameters of the microprocessor and the first synchronous bus can be changed without requiring any changes to the second synchronous bus so that the microprocessor and the first synchronous bus can take advantage of advances in technology while allowing the second synchronous bus and the associated peripheral devices to remain compatible with previous versions of the computer system.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: September 10, 1996
    Assignee: AST Research, Inc.
    Inventors: Thomas E. Ludwig, Thomas W. Craft
  • Patent number: 5455912
    Abstract: A high speed/low overhead bus arbitration apparatus for allocating system bus mastership in a system containing two processing devices. The apparatus includes control logic which controls the access of each of the processing devices to the system bus. The apparatus further includes a multiplexer for selecting the control information presented on the system bus based upon the state of the control logic. The apparatus finally includes a latch for alternatively passing through to and latching onto the system bus, based upon the state of the control logic, an address, which is driven by only one of the processing devices. The control logic transfers access to the system bus from the first processing device to second when the second requests access and the bus is not busy, preventing both processing devices from contending for the system bus by forcing the driving processor device to relinquish the address lines prior to completion of the current bus cycle.
    Type: Grant
    Filed: June 18, 1993
    Date of Patent: October 3, 1995
    Assignee: Vtech Industries, Inc.
    Inventor: Thomas E. Ludwig
  • Patent number: 5438666
    Abstract: An arbitration system for a shared address, data and control bus provides burst mode operations for transferring data between a peripheral device and memory via a bus master. The arbitration system is responsive to high priority bus activities, such as memory refresh cycles and DMA cycles to temporarily transfer control of the shared bus from the bus master to a circuit controlling the high priority activity. After the high priority activity is completed, the arbitration system returns control of the shared bus to the bus master so that the associated peripheral device may continue operating in the burst mode. This transfer of control occurs without requiring the time overhead of arbitrating priority between bus masters having active bus requests. The arbitration system further includes timing circuits to assure that a bus master transferring data in the burst mode does not retain control of the shared bus for an excessive amount of time.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: August 1, 1995
    Assignee: AST Research, Inc.
    Inventors: Thomas W. Craft, Bradley T. Herrin, Thomas E. Ludwig
  • Patent number: 4987529
    Abstract: An arbitration system for a shared address, data and control bus provides burst mode operations for transferring data between a peripheral device and memory via a bus master. The arbitration system is responsive to high priority bus activities, such as memory refresh cycles and DMA cycles to temporarily transfer control of the shared bus from the bus master to a circuit controlling the high priority activity. After the high priority activity is completed, the arbitration system returns control of the shared bus to the bus master so that the associated peripheral device may continue operating in the burst mode. This transfer of control occurs without requiring the time overhead of arbitrating priority between bus masters having active bus requests. The arbitration system further includes timing circuits to assure that a bus master transferring data in the burst mode does not retain control of the shared bus for an excessive amount of time.
    Type: Grant
    Filed: August 11, 1988
    Date of Patent: January 22, 1991
    Assignee: AST Research, Inc.
    Inventors: Thomas W. Craft, Bradley T. Herrin, Thomas E. Ludwig
  • Patent number: 4973860
    Abstract: A circuit for synchronizing an asynchronous input signal with an internal time base clock operates at a high frequency. The circuit includes an input flip-flop that receives the input signal and an output flip-flop that provides an output signal that is synchronized with the internal time base clock. The input flip-flop and the output flip-flop are interconnected via logic circuitry so that any instability on the output of the input flip-flop caused by failure of the input signal to satisfy the setup and hold conditions of the input flip-flop are isolated from the output of the output flip-flop. The output of the output flip-flop is a stable signal that is synchronized with the internal time base clock.
    Type: Grant
    Filed: May 2, 1989
    Date of Patent: November 27, 1990
    Assignee: AST Research Inc.
    Inventor: Thomas E. Ludwig
  • Patent number: 4444592
    Abstract: This invention relates to novel pigmentary products, particularly valuable in the textile art, prepared by using strong acid solvents to solubilize or form fine colloidal dispersions of normally water-insoluble aryl pararosanilines in an aqueous medium. The aryl pararosaniline which is thus solubilized or dispersed is reacted with a heteropoly acid to produce water-insoluble blue-hued pigments. By various modifications in the process, the pigments can be co-precipitated with other pigments and/or dyes to produce pigments or pigment lakes of different shades and intensities.
    Type: Grant
    Filed: November 15, 1982
    Date of Patent: April 24, 1984
    Assignee: The Sherwin-Williams Company
    Inventor: Thomas E. Ludwig