Abstract: A method and apparatus for controlling access to a shared memory in a network system is described. The apparatus includes at least one fast port interface circuit, each comprising a fast input port interface configured to sequentially receive data, address, and command information from a network client at a first data rate in segments of a first width. Each fast input port interface comprises a fast interface register configured to temporarily store the data and address information. Each fast input port interface further comprises a command decode circuit configured to receive the command information and, in response, sequentially store the segments of data and address information in the fast interface register until the fast interface register is full, the fast interface register further configured to be read out in parallel to the shared memory.

Abstract: A cell bus arbitration device and method arbitrating a cell bus transmitting data in a certain size of packet unit is disclosed. The cell bus arbitration device comprises a filter for outputting request signals not to be masked by using service mask data, a decoder for outputting only the highest priority request signal, a latching and counting unit latching and counting the priority signal, a service flag for outputting service mask data according to the bus grant signals, and a detector for detecting the state of the bus request signals and controlling the service flag unit. The device is used for arbitrating a cell bus for transmitting data in packet unit.

Abstract: An apparatus is provided that improves memory storage and access speed by repackaging various types of memories, SRAM, DRAM, and Disk, into a single storage unit. Each unit contains a slice of all the various memories along with programmable logic to control the accessing of the memories. This unit appears to the central processing unit (CPU) of a computer system as an extremely large secondary cache. Independent management of each unit greatly reduces bus traffic to implement any particular address space. By using a plurality of these memory units, an extremely large amount of memory can be accessed by the CPU with the speed of accessing a cache system.

Abstract: A very fast, memory efficient, highly expandable, highly efficient CCNUMA processing system based on a hardware architecture that minimizes system bus contention, maximizes processing forward progress by maintaining strong ordering and avoiding retries, and implements a full-map directory structure cache coherency protocol. A Cache Coherent Non-Uniform Memory Access (CCNUMA) architecture is implemented in a system comprising a plurality of integrated modules each consisting of a motherboard and two daughterboards. The daughterboards, which plug into the motherboard, each contain two Job Processors (JPs), cache memory, and input/output (I/O) capabilities. Located directly on the motherboard are additional integrated I/O capabilities in the form of two Small Computer System Interfaces (SCSI) and one Local Area Network (LAN) interface. The motherboard includes main memory, a memory controller (MC) and directory DRAMs for cache coherency.

Abstract: In this device, each processor (P1 to P3) is associated with at least one dressable space (R1 to R3), whereas all the processors and all the addressable spaces are in communication by way of a common communication bus (BC).Between all the processors and each addressable space is connected an intercommunicating connection node (N1 to N3), each connection node including control means (LC, D1, D2) forensuring priority of access of any processor to its own addressable space; andensuring a hierarchy of priority of access to the addressable spaces of the other processors among said plurality of processors.

Abstract: A naming system for resolution of hierarchically named computer accessible objects to respective object identifiers. The naming system includes a global namer module which is instantiated on multiple systems. Resolution of a hierarchical name begins at a first instance of the global namer module. The first instance resolves one or more successive portions of the hierarchical name to a respective object identifier(s). If the hierarchical name cannot be completely resolved at the first instance, the hierarhcial name is forwarded to a second instance which is referenced by an object identifier identified by the first instance. Resolution then continues at the second instance, and possibly at additional instances of the global namer module, until the last portion of the hierarchical name is resolved to an object identifier. The object identifier is then returned as that of the entire hierarchical name.

Abstract: A device for controlling data transmission between a docking station and a portable computer includes signal control circuitry connected to the docking station for selectively enabling and disabling data transmission between the docking station and the portable computer to enable and disable expanded operating functions of the portable computer, respectively. The signal control circuitry enables and disables the data transmission between the docking station and the portable computer in dependence upon a first signal indicating a power supply state of the docking station, a second signal indicating a power supply state of the portable computer, and a third signal indicating a connection state between the docking station and the portable computer.

Abstract: A SCSI bus extender apparatus coupling a primary SCSI bus to a secondary SCSI bus includes a mechanism for detecting and resolving contention between a substantially simultaneous SELECTION operation on the primary bus and a RESELECTION operation on the secondary bus. The inventive method contemplates the bus extender arbitrating for control of the primary bus after a conflict is detected, and releasing control of the secondary bus if control of the primary bus is obtained. A target device on the secondary bus can then rearbitrate for control of the secondary bus. Once the target device controls the secondary bus, it can direct a RESELECTION signal to the bus extender, which responsively directs the signal to an initiator device on the primary bus. If the bus extender is unable to gain control of the primary bus after a conflict is detected, the SELECTION operation is allowed to proceed and the target device reattempts to assert the RESELECTION operation thereafter.

Abstract: Low-latency distributed round-robin arbitration is used to grant requests for access to a shared resource such as a computer system bus. A plurality of circuit board cards that each include two devices such as CPUs, I/O units, and ram and an address controller plugs into an Address Bus in the bus system. Each address controller contains logic implementing the arbitration mechanism with a two-level hierarchy: a single top arbitrator and preferably four leaf arbitrators. Each address controller is coupled to two devices and the logical "OR" of their arbitration request is coupled via an Arbitration Bus to other address controllers on other boards. Each leaf arbitrator has four prioritized request in lines, each such line being coupled to a single address controller serviced by that leaf arbitrator. By default, each leaf arbitrator and the top arbitrator implement a prioritized algorithm.

Abstract: The present invention is directed to providing a computer system which arbitrates control of a shared bus among plural devices included in the computer system. In accordance with the present invention, at least one of the devices is afforded a higher priority than the remaining devices, yet none of the remaining devices are effectively denied system bus access or control for extended periods of time. The present invention can therefore increase operating efficiency even as the number of devices included in the computer system is increased to achieve enhanced processing power. In addition, the present invention can provide sophisticated multimedia features, including real time signal processing, without sacrificing overall operating efficiency.

Abstract: An arbitration scheme for a computer system having multiple arbiters for arbitrating access to a plurality of buses. In the preferred embodiment, a computer system is divided into a detachable laptop portion and an expansion base unit coupled through a shared PCI bus. Each of the two portions of the computer system includes separate PCI arbitration circuitry for arbitrating requests for the PCI bus from potential PCI and ISA bus masters. Included within the laptop portion of the computer system is a top level arbiter that determines whether the PCI arbiter in the laptop or expansion base unit has access to the PCI bus. Either PCI arbiter normally must receive a grant from the top level arbiter before it runs a cycle. While the laptop computer is docked, the top level arbiter selects between the PCI arbiters on an essentially time multiplexed basis. While the expansion base and laptop computer are undocked, the top level arbiter grants bus access to the laptop PCI arbiter.

Abstract: An apparatus controls a signal that indicates to a plug-in component board that it is to be connected to a 64-bit data path in a computer system. The apparatus comprises a timing circuit for receiving a reset signal and providing first and second complementary logical signals in response thereto. A selection switch receives the first and second logical signals as well as a control signal and outputs a third signal as determined by the logical level of the reset signal. A method involves generating first and second complementary signals from a reset signal, selecting between the first complementary signal and a control signal, and outputting a third signal, the logical value of the third signal being determined by the logical value of at least one of the reset signal and the control signal.

Abstract: A system and method are presented for transmitting data upon an address portion of a computer system bus during periods of maximum or near-maximum utilization of a data portion of the bus. One embodiment of the computer system includes at least one central processing unit (CPU) and a main memory coupled to a processor bus. The main memory stores data, and the CPU executes instructions stored within the main memory. The processor bus is a split transaction bus. The processor bus is divided into an address bus, a data bus, and a control bus including address, data, and control signal lines, respectively. The CPU and the main memory each include a bus interface, and are coupled to the processor bus via the bus interface. The bus interface includes a transaction queue coupled to an interface unit. The interface unit is coupled to the address, data, and control buses, and performs bus transactions (i.e., read and/or write transactions) upon the processor bus.