Abstract: A computer system having a core logic chipset that functions as a bridge between an Accelerated Graphics Port ("AGP") bus device such as a graphics controller, and a host processor and computer system memory wherein a Graphics Address Remapping Table ("GART table") is used by the core logic chipset to remap virtual memory addresses used by the AGP graphics controller into physical memory addresses that reside in the computer system memory The GART table enables the AGP graphics controller to work in contiguous virtual memory address space, but actually use non-contiguous blocks or pages of physical system memory to store textures, command lists and the like. The GART table is made up of a plurality of entries, each entry comprising an address pointer to a base address of a page of graphics data in memory. The core logic chipset may cache a subset of the most recently used GART table entries to increase AGP performance when performing the address translation.

Abstract: A computer is provided having a bus interface unit between a CPU bus and a memory bus. The bus interface unit includes a memory controller and a read/write queue manager. The memory controller dispatches, or removes read requests or write requests from respective read or write requests queues depending on various modes of operation. Typically, the read requests are dispatched or removed either singularly or as a programmed series of read requests prioritized over write requests unless the write request queue is almost full. If the write request queue is almost full, then write request are removed either singularly or in a series before servicing the read request queue. The number of read or write request being removed from their respective queues can be programmed within a configuration register operably coupled to a controller arranged between the read and write request queues. The memory controller determines how many requests will be serviced within possibly a lengthy series of requests.

Abstract: A method for providing secure registration and integrity assessment of software in a computer system is disclosed. A secure hash table is created containing a list of secure programs that the user wants to validate prior to execution. The table contains a secure hash value (i.e., a value generated by modification detection code) for each of these programs as originally installed on the computer system. This hash table is stored in protected memory that can only be accessed when the computer system is in system management mode. Following an attempt to execute a secured program, a system management interrupt is generated. An SMI handler then generates a current hash value for the program to be executed. In the event that the current hash value matches the stored hash value, the integrity of the program is guaranteed and it is loaded into memory and executed.

Abstract: A battery pack which contains an integral bidirectional up/down voltage converter, so that the voltage of the battery does not have to match the voltage of the system power lines at all. Thus a single battery pack can be used in different systems which have different power bus voltages.

Abstract: A distributed interrupt controller system for use in a multiprocessor environment, having at least two local programmable interrupt controllers (LOPICs) coupled to at least one central programmable interrupt controller (COPIC) via a dedicated bus. One of the at least one COPICs functions as a master arbiter, while the LOPICs, each of which may be integrated with its corresponding processing unit, and other non-master COPICs are treated as bus agents. Bus grant is achieved by a "round robin" arbitration protocol. For distributed delivery of interrupts, the master arbiter compares a current-task-priority-register value associated with each bus agent to determine the agent that is least busy for delivery of the interrupt thereto.

Abstract: A universal battery pack in which an internal switch-mode power converter's control circuitry is powered from the battery side of the converter, rather than from the system side.

Abstract: A combination support and heat sink structure is mounted within a computer housing for pivotal movement between connected and disconnected positions and includes a pair of cooling plates, one air cooled and the other liquid cooled, carried in a spaced apart, parallel opposing relationship. The two cooling plates are movable toward and away from one another and a pair of manually operable spring clip members permit a processor card to be removably sandwiched and clamped between the cooling plates without the use of tools.

Abstract: An apparatus handles long latency interrupt signals in a computer which posts I/O write operations. The apparatus includes a posting buffer for posting write operations and circuitry for ensuring that End-of-Interrupt (EOI) write operations (and other interrupt controller directed I/O operations) are properly synchronized to prevent false interrupts from reaching the processor. Upon receipt of the EOI write operation, the apparatus verifies that the posting buffer is empty before it imposes a pre-determined delay to ensure sufficient time for the cleared the interrupt signal to be transmitted over the interrupt serial bus. Next, the apparatus checks the interrupt serial bus for activities. If the interrupt serial bus is idle, the EOI write operation is issued to the interrupt controller. Alternatively, the apparatus waits until the serial bus becomes inactive for two back-to-back cycles before allowing the EOI write operation to be issued to the interrupt controller.

Abstract: A computer system has a bus, a connector for a circuit card, and a clamp configured to selectively prevent removal of the circuit card from the connector when the clamp is engaged. The computer system has circuitry connected to monitor the engagement status of the clamp and to regulate delivery of power to the connector based on the engagement state of the clamp.

Abstract: A computer system including a small array of backlit buttons that can be used to control certain computer system functions. Each button includes a built-in backlight which preferably is a light emitting diode ("LED") that allows a user to see more easily the label on the button. Visual feedback that a button is pressed is provided to the user by turning off a button's backlight when the button is pressed. Thus, once the light in a button turns off, the user knows the button has been depressed sufficiently to activate the function associated with the button. In another aspect of the invention, the computer system may enter a low power consumption sleep mode in which most of the computer's functions are disabled. In the sleep mode the backlights in the button array are turned off to further save power. The computer system also includes a telephone answering machine ("TAM") capability which includes a backlit button that allows the user to play back a previously recorded telephone message.

Abstract: A method and apparatus for providing a programmable device with operational parameters applicable to successive operational environments. According to some aspects, the method includes the steps of programming memory with a common operational code applicable to multiple operational environments, programming memory with a first operational environment dependent code, operating said device in a first operational environment, changing to a second operational environment, adding a second operational environment dependent code, and operating in a second operational environment. According to some aspects, the apparatus comprises a programmable device operating according to a set of operational parameters reprogrammably stored therein.

Abstract: A memory controller which provides a series of queues between the processor and the PCI bus and the memory system. Memory coherency is maintained in two different ways. Before any read operations are accepted from the PCI bus, both of the posting queues must be empty. A content addressable memory (CAM) is utilized as the PCI to memory queue. When the processor performs a read request, the CAM is checked to determine if one of the pending write operations in the PCI to memory queue is to the same address as the read operation of the processor. If so, the read operation is not executed until the PCI memory queue is cleared of the write. To resolve the problem of aborting a Memory Read Multiple operation, an abort signal from the PCI bus interface is received and as soon thereafter as can be done the read ahead cycle is terminated, even though the read ahead cycle has not fully completed.

Abstract: A bus ring-back and voltage over-shoot reduction apparatus with capability for rendering an expansion slot of a computer system hot-pluggable, wherein a logic gate controls a switching element so that when the element is turned on, the input and output (I/O) nodes of the element are in a low ohmic conductive relationship. One of the I/O nodes is coupled to an expansion card whereas the other node is coupled to a bus to which the expansion slot is connected. The apparatus operates as a level shifter wherein the output node voltage follows the input node voltage until pinch-off such that the output voltage remains substantially stable thereafter. The apparatus also isolates the expansion card from the bus when the system is running or during the powering up of the card.

Abstract: A computer system having a core logic chipset that functions as a bridge between an Accelerated Graphics Port ("AGP") bus device such as a graphics controller, and a host processor and computer system memory wherein a Graphics Address Remapping Table ("GART table") is used by the core logic chipset to remap virtual memory addresses used by the AGP graphics controller into physical memory addresses that reside in the computer system memory. The GART table enables the AGP graphics controller to work in contiguous virtual memory address space, but actually use non-contiguous blocks or pages of physical system memory to store textures, command lists and the like. A plurality of AGP memory-mapped status and control registers are stored in the computer system memory, and are used for status and control of AGP functions in the computer system.

Abstract: A portable computer docking station has incorporated therein a motorized docking/undocking module which is releasably latched to a housing wall portion of the docking station. The module includes a housing within which a small electric drive motor is operatively mounted, with wall portions of the module housing translationally and rotationally restraining the motor body without the use of screws or other separate fastening members. A docking control system, upon sensing the manual placement of a portable computer on a receiving area adjacent the module energizes the module motor which rotates a cammed worm gear portion of the module which is drivingly linked to latching and ejection portions of the module. The motor-driven latching portion of the module connects to the computer and docks it by forcibly drawing it toward the module in a manner mating facing connectors on the computer and docking station.

Abstract: The placement of components on a circuit board may be controlled automatically by creating a group containing two or more types of components to be placed on the circuit board and by developing a placement path by which any component within the group may be placed on the circuit board at any point along the placement path.

Abstract: A computer docking station is provided which, in a disclosed embodiment thereof, includes multiple security features. The security features are operable to prevent access to interior portions of the docking station, prevent access to a card bay of the docking station, prevent ejection of a disk drive from a disk drive module of the docking station, and prevent operation of the disk drive module. Operation of the security features may be simultaneously and conveniently initiated by rotating a keyed lock mechanism to thereby rotate a cam mounted thereto.

Abstract: A computer system having a core logic chipset that functions as a bridge between an Accelerated Graphics Port ("AGP") bus device such as a graphics controller, and a host processor and computer system memory wherein a Graphics Address Remapping Table ("GART table") is used by the core logic chipset to remap virtual memory addresses used by the AGP graphics controller into physical memory addresses that reside in the computer system memory. The GART table enables the AGP graphics controller to work in contiguous virtual memory address space, but actually use non-contiguous blocks or pages of physical system memory to store textures, command lists and the like. The GART table is made up of a plurality of entries, each entry comprising an address pointer to a base address of a page of graphics data in the computer system physical memory, and feature flags that may be used to customize the associated page of graphics data.

Abstract: A signal represented as a matrix of input values is adaptively filtered using a processor with a multimedia extension unit. A plurality of coefficients are loaded into a first vector register and input values are loaded into a second vector register. Next, for each of the coefficients in the first vector register, (1) a single cycle vector multiply-accumulate operation is performed between the selected coefficient and the input values stored in the second vector register and the result is stored in a third register; (2) a partition-shift on input values in the second vector register is then performed and a new input value is then moved into the second vector register. After each of the four loaded coefficients have been processed, the results are saved and the operation is repeated until all input values in the matrix have been processed.