Michael J Mahon, Allen Baum, William R Bryg, Terrence C Miller: Privilege level checking instruction for implementing a secure hierarchical computer system. Hewlett Packard Company, February 28, 1989: US04809160 (112 worldwide citation)

A low overhead way for insuring that only routines of sufficient privilege can execute on a secured page of memory in an hierarchial computer system, and for raising the privilege level of a low privilege process in an orderly and secure way is presented. This is done through the execution of a sing ...

Steven C Boettner, William R Bryg, David V James, Tso Kai Liu, Michael J Mahon, Terrence C Miller, William S Worley Jr: Direct input/output in a virtual memory system. Hewlett Packard Company, October 11, 1988: US04777589 (69 worldwide citation)

A virtual memory system is used to control access to I/O device address space in accordance with a preferred embodiment of the present invention. In a virtual memory system, access to pages within a processor's address space are assigned to each application program. Each I/O device is assigned two p ...

Allen Baum, William R Bryg, Michael J Mahon, Ruby B Lee, Steven S Muchnick: Cache memory with variable fetch and replacement schemes. Hewlett Packard Company, Roland I Griffin, Alan H Haggard, May 22, 1990: US04928239 (58 worldwide citation)

An instruction is presented to the cache; the instruction includes a cache control specifier which identifies a type of data being requested. Based on the cache control specifier, one of a plurality of replacement schemes is selected for swapping a data block out of the cache.

Ruby B Lee, Michael J Mahon: Computer providing flexible processor extension, flexible instruction set extension, and implicit emulation for upward software compatibility. Hewlett Packard Company, Douglas L Weller, August 9, 1988: US04763242 (53 worldwide citation)

A computer and an instruction set are presented which allow for a number of assists to be easily incorporated into the computer, and which allow for an instruction set extension. The computer is designed to support instructions which move data between an assist and a location, although an assist's o ...

Ruby Bei Loh Lee, Michael J Mahon: Expediting blending and interpolation via multiplication. Hewlett Packard Company, May 26, 1998: US05757377 (28 worldwide citation)

Circuitry combines a first operand A.sub.0, a second operand A.sub.1, and a third operand X in a blend function to produce a result Z. The result Z has a value equal to X*A.sub.0 +(1-X)* A.sub.1. The circuitry includes a plurality of logic gates organized in rows. When performing the blend operation ...

Michael J Mahon, Roy R Shanks: Controlled selective disconnect system for wafer scale integrated circuits. Burroughs Corporation, Mervyn L Young, Kevin R Peterson, May 11, 1982: US04329685 (27 worldwide citation)

This disclosure relates to a controlled selective power disconnect means for employment with the various circuits implemented on a crystalline wafer so that a particular circuit can be selectively disconnected when it has developed a defect or short or is unwanted in the system for other reasons. Th ...

Michael J Mahon: Automatic power disconnect system for wafer scale integrated circuits. Burroughs Corporation, M L Young, K R Peterson, October 12, 1982: US04354217 (14 worldwide citation)

This disclosure relates to a wafer scale power interconnect system by which defective circuits on the wafer can be automatically disconnected from the power and ground lines supplied to each of the circuits. The disconnect device employs a gate between the power source and the circuit, which gate is ...

Daryl K Odnert, Michael J Mahon, Dale C Morris, Jerome C Huck, Ruby B Lee, Stephen G Burger, William R Bryg, Vivek S Pendharkar: Software method for implementing dismissible instructions on a computer. Hewlett Packard Company, Roland I Griffin, Alan H Haggard, January 11, 1994: US05278985 (7 worldwide citation)

A method for operating a digital computer in response to the occurrence of an exception is disclosed. The method provides for the examination both of the contents of a predetermined computer location and of the instruction code for the instruction causing the exception. The computer then utilizes th ...

Michael J Mahon, Allen Baum: Method in a computing system for performing a multiplication. Hewlett Packard Company, Roland I Griffin, Alan H Haggard, August 7, 1990: US04947364 (4 worldwide citation)

In a computing system a method for performing a multiplication of a first multiplicand and a second multiplicand is presented. The computing system includes a plurality of registers, an instruction decoder, an arithmetic logic unit, and a preshifter. The first multiplicand is divided into a pluralit ...

Bret A McKee, Blaine D Gaither, Michael J Mahon: Method and apparatus for gathering three dimensional data with a digital imaging system. Hewlett Packard Development Company, Leslie P Gehman, September 27, 2005: US06950135 (3 worldwide citation)

A digital image capture device including circuits capable of measuring the distance between the image capture device and an imaged object allows the capture of three-dimensional data of the surface of the object facing the image capture device. The distance data is obtained by the addition of a flas ...