Patents by Inventor Bernard C. Drerup

Bernard C. Drerup 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: 5564027
    Abstract: A bus interface with resources to selectively optimize burst mode data transfers from one bus to another through an automated selection and generation of a cadence. In one form, the cadence is selected based upon memory access latency characteristics, the relative widths of the busses, and the relative clock frequencies of the busses. The selected cadence is provided as a pacing ready signal to the bus receiving the transferred data.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: October 8, 1996
    Assignee: International Business Machines Corporation
    Inventors: Hai Q. Bui, Sean E. Curry, Bernard C. Drerup
  • Patent number: 5377331
    Abstract: A method and apparatus are disclosed for allowing at least one computer subsystem, having a central arbiter, to be interconnected with a host system also including a central arbiter. Conversion logic is added to each computer subsystem desired to be interconnected to the host. The conversion logic is positioned between the arbitration buses of the host system and the subsystem and includes two requesting arbiters, one of which arbitrates for the host system arbitration bus, and the other which arbitrates for the subsystem arbitration bus. At the default state, the conversion logic has successfully arbitrated for, and is maintaining control of the subsystem bus. After a request from a subsystem device for access to the host bus, the conversion logic arbitrates for control of the host bus. When control of the host bus is awarded to the conversion logic, control of the subsystem bus is released and the requesting subsystem device can transfer data between the subsystem and host.
    Type: Grant
    Filed: March 26, 1992
    Date of Patent: December 27, 1994
    Assignee: International Business Machines Corporation
    Inventors: Bernard C. Drerup, James C. Peterson
  • Patent number: 5333285
    Abstract: A hardware and software mechanism is provided for ensuring that a feature processor card, included with other feature cards in a host system, can be reset without interrupting software running on other feature cards. A delay is provided that starts counting each time a watchdog timer expires. If the watchdog timer is reset by an interrupt service routine, then the feature card processor is assumed to be reset. But, if the watchdog timer is not reset before the delay timer expires, then it is assumed that service routine is corrupt and that external reset of the feature card is required. Upon expiration of the watchdog, an error signal is sent, via the system bus, to the host CPU. Recovery code that is resident on the host CPU is then run and resets the CPU on the feature card. A reset signal is output from the host CPU, via the system bus, to a reset register on the feature card which then forwards the signal to the feature card CPU, thereby initiating reset of the system.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: July 26, 1994
    Assignee: International Business Machines Corporation
    Inventor: Bernard C. Drerup