Patents Represented by Attorney, Agent or Law Firm Samuel G. Campbell, III
  • Patent number: 8220060
    Abstract: Approaches for protecting design information are disclosed. In one approach, a request for an IP core from an integrated circuit device is received, and the request includes identification information. An identifier range is determined from the identification information. The identifier range includes a plurality of unique device identifiers identifying a plurality of integrated circuit devices that are allowed to receive the IP core. The identifier range is downloaded to the integrated circuit device, which evaluates whether or not a unique device identifier that is stored on the integrated circuit device is within the downloaded identifier range. The IP core is programmed into the integrated circuit in response to the unique device identifier that is stored on the integrated circuit device being within the downloaded identifier range.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: July 10, 2012
    Assignee: Xilinx, Inc.
    Inventor: James M. Simkins
  • Patent number: 7757294
    Abstract: A method and system for maintaining the security of design information is disclosed. The method includes generating an encrypted IP core by encrypting an IP core using a public key, downloading the encrypted IP core to a programmable logic device (PLD), and recovering the IP core by decrypting the encrypted IP core using a private key. The private key is associated with the PLD, and the public key and the private key correspond to one another. The method may further include the PLD receiving authorization information corresponding to the IP core and comparing local authorization information stored at the PLD with the authorization information.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: July 13, 2010
    Assignee: Xilinx, Inc.
    Inventor: James M. Simkins
  • Patent number: 7623660
    Abstract: A method and system for pipelined decryption is disclosed. One embodiment includes a circuit having an iterative calculation section and a cipher text storage section in support of cipher block chaining (CBC) encryption mode. The iterative calculation section may be pipelined and configured to process multiple ciphertexts at once for increased throughput.
    Type: Grant
    Filed: February 1, 2005
    Date of Patent: November 24, 2009
    Assignee: Xilinx, Inc.
    Inventor: Warren E. Cory
  • Patent number: 6819312
    Abstract: A set of haptic elements (haptels) are arranged in a grid. Each haptel is a haptic feedback device with linear motion and a touchable surface substantially perpendicular to the direction of motion. In a preferred embodiment, each haptel has a position sensor which measures the vertical position of the surface within its range of travel, a linear actuator which provides a controllable vertical bi-directional feedback force, and a touch location sensor on the touchable surface. All haptels have their sensors and effectors interfaced to a control processor. The touch location sensor readings are processed and sent to a computer, which returns the type of haptic response to use for each touch in progress. The control processor reads the position sensors, derives velocity, acceleration, net force and applied force measurements, and computes the desired force response for each haptel. The haptels are coordinated such that force feedback for a single touch is distributed across all haptels involved.
    Type: Grant
    Filed: November 1, 2001
    Date of Patent: November 16, 2004
    Assignee: Tactiva Incorporated
    Inventor: Daniel E. Fish
  • Patent number: 6772270
    Abstract: A multi-port Fibre Channel controller is disclosed. Such a multi-port Fibre Channel controller includes a number of Fibre Channel ports, an interface unit coupled to each one of the Fibre Channel ports, a Fibre Channel controller, and a processor. The processor is coupled to the Fibre Channel controller, and the Fibre Channel controller is coupled to control the interface unit and coupled to the subsystem interface. Such a multi-port Fibre Channel controller may be configured as a dual-port Fibre Channel controller by, for example, employing only two Fibre Channel ports (i.e., a first Fibre Channel port and a second Fibre Channel port).
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: August 3, 2004
    Assignee: Vicom Systems, Inc.
    Inventor: Dietmar M. Kurpanek
  • Patent number: 6727837
    Abstract: A method and a system for acquiring local signal behavior parameters (LSBPs) of a band-limited (BL) signa, for representing and processing the signal, wherein the LSBPs encode the signal's local behavior in between Nyquist rate points. Preferably, a section of a BL signal within a sampling window is represented as a truncated series of order n at a sampling moment within the sampling window. The truncated series having n+1 LSBPs as its coefficients, encoding the signal's local behavior between Nyquist rate points. Compared to the conventional approach that encodes a signal's behavior by signal samples taken at Nyquist rate points, the invention encodes more signal behavior. Discrete signal samples are obtained from the signal. The LSBPs are solved numerically such that the interpolated values of the truncated series provide the least-square fit with the discrete signal samples.
    Type: Grant
    Filed: July 13, 2001
    Date of Patent: April 27, 2004
    Assignee: Kromos Communications, Inc.
    Inventors: Aleksandar Ignjatovic, Nicholas A. Carlin
  • Patent number: 6724757
    Abstract: A signal router, configured to receive information carried by a first signal and transmit the information on a second signal, is described. The signal router, using routing information it gathers, selects the second signal from a number of signals, with the first and the second signals differing in at least one physical characteristic. The signal router operates in a network of a number of such signal routers, and so each one of the signal routers is coupled to at least one of the other signal routers. The routing information is used to create a circuit from a first one of the signal routers to a second one of the signal routers. Once the circuit is created, the information is routed over the circuit. According to one aspect of the present invention, the signals are optical signals.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: April 20, 2004
    Assignee: Cisco Technology, Inc.
    Inventors: Haig Michael Zadikian, Ali Najib Saleh, John Conlon Adler, Zareh Baghdasarian, Vahid Parsi
  • Patent number: 6694381
    Abstract: A method and apparatus implement a communications protocol whereby a host application program can communicate with a computer subsystem without the use of special driver software. In this way, the application program is able to invoke virtually any vendor-unique function on a compatible subsystem controller using only standard read/write system calls. This avoids platform dependency and greatly improves the portability of the application program.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: February 17, 2004
    Assignee: Vicom Systems, Inc.
    Inventors: Horatio Lo, David Lee
  • Patent number: 6684193
    Abstract: A method and apparatus providing for an efficient solution to the multivariate allocation of resources are described. A model is formulated that derives the relationship between a set of resources and a set of refinements, wherein any of a number of resources are used to build or comprise a refinement. The model provides for at least: the resource consumption as based upon the relationship between each refinement and its set of supporting resources, a demand distribution of the refinements, and a value function. Each resource, and the refinements that it supports, generates a resource hyperplane in a demand space, and the complete set of refinements generates an intersecting set of hyperplanes forming a polytope on which resource allocation fulfills refinement demand. An expected value function is thereafter formulated and transformed into a closed form solution.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: January 27, 2004
    Assignee: Rapt Technologies Corporation
    Inventors: Thomas A. Chavez, Paul Dagum
  • Patent number: 6634024
    Abstract: The present invention integrates data prefetching into a modulo scheduling technique to provide for the generation of assembly code having improved performance. Modulo scheduling can produce optimal steady state code for many important cases by sufficiently separating defining instructions (producers) from using instructions (consumers), thereby avoiding machine stall cycles and simultaneously maximizing processor utilization. Integrating data prefetching within modulo scheduling yields high performance assembly code by prefetching data from memory while at the same time using modulo scheduling to efficiently schedule the remaining operations. The invention integrates data prefetching into modulo scheduling by postponing prefetch insertion until after modulo scheduling is complete. Actual insertion of the prefetch instructions occurs in a postpass after the generation of appropriate prologue-kernel-epilogue code.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: October 14, 2003
    Assignee: Sun Microsystems, Inc.
    Inventors: Partha Pal Tirumalai, Rajagopalan Mahadevan
  • Patent number: 6594148
    Abstract: A high efficiency multi-directional airflow system for a telecommunications equipment assembly used for housing electronic apparatuses which facilitate telecommunications functionality. The equipment assembly defines an internal cavity which can be divided into a plurality of air flow channels. Each of the plurality of air flow channels captures a sub-portion of the overall volume provided by the internal cavity. The smaller volume flow channels provide a smaller cross-sectional area through which the majority of air travels. Since the cross-sectional area is smaller, the velocity of the air through the flow channels is increased. Since the air velocity is increased, the heat transfer coefficient is also increased, thus allowing for the more efficient removal of heat from the electronic apparatuses. A set of fan trays can include a plurality of fans each directionally positioned to work in series to cause air to flow through the plurality of flow channels.
    Type: Grant
    Filed: January 16, 2002
    Date of Patent: July 15, 2003
    Assignee: Cisco Technology, Inc.
    Inventors: Hiep X. Nguyen, Maurice M. Guy, Osvaldo Garcia
  • Patent number: 6587064
    Abstract: A signal processor and method of signal processing is disclosed. The signal processor includes a differentiator and an extrapolator coupled to the differentiator. The differentiator is configured to receive an input signal and to generate a vector. The input signal is band-limited. The vector includes at least one chromatic derivative. The extrapolator is coupled to the differentiator and is configured to generate an output signal.
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: July 1, 2003
    Assignee: Kromos Communications, Inc.
    Inventors: Matthew Cushman, Aleksander Ignjatovic
  • Patent number: 6560605
    Abstract: A system for presenting hypermedia link information. A computer-implemented method for presenting hypermedia link information is described which relates to the user the characteristics of a data file pointed to by the hypermedia link. The computer system waits for an event to occur. This event is the user or system selecting one or more hypermedia links. The hypermedia link in this scenario points to a data file about which information is to be gathered. The computer system then requests information about the data file. In one embodiment, a cue is generated to communicate information about said data file to a user. This information may be conveyed to the user by auditory or visual means, such as a pop-up information box on the user's display. A powerful and convenient system for browsing hypermedia information is thus provided.
    Type: Grant
    Filed: August 21, 2001
    Date of Patent: May 6, 2003
    Assignee: Sun Microsystems, Inc.
    Inventors: Michael C. Albers, Eric D. Bergman
  • Patent number: 6535008
    Abstract: A fixture is provided for use in connection with a circuit board tester. The fixture can move the unit under test (UUT), against the urging or a set of springs, to a first position in which the UUT contacts all probes of the tester, for performing a first set of tests. A partial vacuum is created in the region near the probes to permit atmospheric pressure to move the UUT to the first position. A movable or actuateable limiting member is moved to a position which can engage a fixture member in a manner such that, upon movement of the UUT in a direction away from the probes, when the vacuum is released, the amount of movement is limited, to position the UUT to contact only the taller probes. The actuator may engage any of various parts of the fixture, or a pocket found therein, including support plates or lids, or may contact a surface of the UUT.
    Type: Grant
    Filed: August 8, 2001
    Date of Patent: March 18, 2003
    Assignee: Cisco Technology, Inc.
    Inventor: Charles Casale
  • Patent number: 6516383
    Abstract: Techniques for the efficient location of free entries for use in performing insert operations in a binary or ternary content addressable memory. As used in data communications and packet routing, such memories often rely on an organization that maintains entries of the same “length” within defined regions. The present invention keeps the free entries (holes) compacted into a contiguous subregion within each region, without requiring hole movement during deletes. These positive effects are accomplished by initially pre-filling the entire memory with a set of hole codes that each uniquely identify the holes in each region. A conventional memory write is then performed to load routing data into the memory. Typically, such routing information will not fill the entire memory, leaving unused entries (containing the region appropriate hole code) in each region. As entries need to be deleted, they are simply replaced by writing in the region-unique hole code.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: February 4, 2003
    Assignee: Cisco Technology, Inc.
    Inventors: Abhijit Patra, Rina Panigrahy, Samar Sharma
  • Patent number: 6484293
    Abstract: A Scheme-1 Termination scheme maximizes system signaling rates by minimizing the signal settling-time when the distance from the middle node to the intersection of the transmission lines is much smaller than the sum of the distances from the end nodes to the intersection of the transmission lines. If the distance from the middle node to the intersection of the transmission lines is not much smaller than the sum of the distances from the end nodes to the intersection of the transmission lines, it has been discovered that a Scheme-2 Termination scheme minimizes the signal settling-time. Alternately, when a Scheme-3 Termination scheme is available, the Scheme-3 Termination scheme maximizes system signaling rates by minimizing the signal settling time when the third transmission line length is more than the second transmission line length divided by two. Otherwise a Scheme-1 Termination scheme minimizes the signal settling time.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: November 19, 2002
    Assignee: Sun Microsystems, Inc.
    Inventor: Jonathan E. Starr
  • Patent number: 6438606
    Abstract: A multi-network system is provided with a facility for storing an old or superseded router image without the need for increasing router memory. A local storage device is coupled, directly or indirectly, to a router. Before a new image is downloaded to the router, the old or superseded image is first stored in the support device. If the new image is defective or undesirable, the old image can be recovered, even if the wide area link is unopenable, by reloading the old image from the local storage device.
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: August 20, 2002
    Assignee: Cisco Technology, Inc.
    Inventor: Paul Ward
  • Patent number: 6433603
    Abstract: An integrated circuit device for synchronization of data in a data path includes a driver and a storage element coupled to the driver for driving the storage element. The storage element is coupled to the data path outside the data path. The integrated circuit employs a method of operation including passing a time pulse, sampling data during the time pulse, passing the data to a computation logic along a data path, and storing the sampled data in a storage element connected to but outside the data path.
    Type: Grant
    Filed: August 14, 2000
    Date of Patent: August 13, 2002
    Assignee: Sun Microsystems, Inc.
    Inventors: Gajendra P. Singh, Joseph I. Chamdani
  • Patent number: 6412635
    Abstract: An item to be packaged which has at least a first substantially planar surface is positioned within the carton, also having at least a first substantially planar exterior carton surface such that the plane of the item to be packaged is non-orthogonal to and non-parallel with the plane of the carton exterior. In one aspect, a substantially parallelepiped-shaped item is rotated about one, two or three orthogonal axes for placing in a carton which may itself have a substantially parallelepiped exterior shape.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: July 2, 2002
    Assignee: Cisco Technology, Inc.
    Inventor: Torence Lu
  • Patent number: 6414561
    Abstract: A conductive area or layer of a circuit board is aligned with, and spaced from, a portion of a first differential signal conductor pair and connected through a conductive pathway to one of the conductors of a second differential signal conductor pair to provide capacitive coupling for compensating an imbalance arising from non-symmetric pin assignments. By compensating the imbalance, signal quality and/or immunity is improved and noise and/or emission is reduced.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: July 2, 2002
    Assignee: Cisco Technology, Inc.
    Inventor: Neven Pischl