Abstract: An apparatus for suppressing the effect of noise from a first circuit on the performance of a second circuit wherein the first and second circuits are on a common substrate. Each of the first and second circuits include first and second supply rails. The apparatus includes a noise isolation circuit and a noise transference circuit. The noise isolation circuit is for coupling the first supply rails of the first and second circuits to prevent noise on the first supply rail of the first circuit from transferring to the first supply rail of the second circuit. The noise transference circuit is for coupling the second supply rails of the first and second circuits so that noise on the second supply rail of the first circuit is transferred to the second supply rail of the second circuit.

Abstract: Data structures, methods, and devices for facilitating servant invocation in a distributed client-server based object oriented operating system are disclosed. In one aspect of the invention, descriptor data structures, which contain a typecode indicator, a marshaling function identifier, and an unmarshaling function identifier, are used to enable modules of application code to be shared between different objects, thereby facilitating servant invocation by increasing the amount of commonized code in the operating system. In another aspect of the invention, a server invocation object is used in the execution of a method call. In still another aspect of the invention, a commonized code base is used to process typecode interpreted and compiled calls to a server process.

Abstract: A new file system partition is added to an existing partition in disk storage space by creating a new file in the existing storage space of the existing partition and giving this file the attributes of a partition. This new file having partition attributes is referred to as a "raw file." Apparatus in a computing system for creating and accessing a raw file would comprise a storage system controller for creating a raw file of a predetermined size with the attributes of a partition, a storage space driver for accessing storage space in a data storage system and a storage access control for translating an access request for a raw file to an actual address for the raw file so the storage space driver can access the raw file based on the actual address for the raw file.

Abstract: Inconsistencies between cache and memory in a memory system operating in a computer are traced and corrected. A cache entry is checked against a counterpart memory entry to trace inconsistencies between the cache entry and the memory entry and to correct the cache entry. A page table entry in memory with a zero mapping mark is checked against a counterpart page entry in a translation lookaside buffer. Inconsistencies between the page table entry with a zero mapping mark and the existence of a counterpart page entry in the translation lookaside buffer is traced. The inconsistency is corrected by deleting the counterpart page entry in the translation lookaside buffer. Address mapping is checked comparing a page entry in the translation lookaside buffer against a counterpart page table entry in the memory. Inconsistencies between the page entry and the page table entry are traced and corrected.

Abstract: A database system wherein one or more entry databases store a plurality of entries. Each entry is of a given type that defines the fields of the entry. Each of the fields contains or identifies an object with associated attributes or data. The type of each entry may further define behavior in the form of methods the entry is configured to implement. An entry type which is a subtype of another inherits all of the fields and behavior of its supertype, and contains additional fields and/or defines new/modified behavior. Entries may be expressed in a Java.TM. class of the Java.TM. programming language. The database system may further employ a search engine which allows queries to be made upon entries in the database. In one implementation, the queries include a read operation, a take operation, and a notify operation. Each query request includes a command indicating the type of operation, and a template which is an entry object having some or all of its fields set to specified values that must be matched exactly.

Abstract: A method of providing a graphical user interface on a client network device is described. The client network device is coupled to a server network device and has a local storage facility, such as a hard disk unit, storing a first version of a software program. The method requires the selection of the first version of the software program as an execution version of the software program. A graphic object identifying the software program is displayed, the graphic object being user selectable to execute the execution version of the software program. A version control indicator, for example an icon, is displayed and indicates to a user of the client network device whether or not a second version of the software program, propagated to the client network device from the server network device, will automatically be selected as the execution version of the software program.

Abstract: A clock recovery circuit uses a pair of variable delay lines to recover clock from a non-return to zero (NRZ) data stream. If an incoming clock transition occurs in the NRZ data, it is passed through one delay line to the output. If no incoming transition occurs, the transition at the output of the first delay line is recycled back through the second delay line. The outputs of the first and second delay lines are combined so that a transition occurs at every possible transition instant, regardless of whether a transition is present in the incoming data at the corresponding time. This permits the benefits of a delay locked loop to be achieved when using NRZ data. Applications of the clock recovery circuits to gigabit data communications systems are describe.

Abstract: An active digital voltage regulator circuit is a two terminal device that is connected in shunt to first and second power supply input lines. The active digital voltage regulator circuit stores energy during times when the local power supply voltage is greater than a predefined voltage, e.g., during times when the parasitic inductances supplement the local power supply voltage. The active digital voltage regulator circuit uses the stored energy to supplement the local power supply voltage during times when the local power supply voltage starts to collapse, e.g., during periods when inductive losses are preventing the power supply from maintaining the local power supply voltage. Consequently, digital active voltage regulator circuit smooths the local power supply voltage by greatly ameliorating the ripple voltages associated with parasitic inductances and resistances. A control circuit within the regulator circuit is a combination of two self-biasing and off-set nulling power supply monitor circuits.

Abstract: CSMA/CD is used to implement flow control in a full-duplex Ethernet network in a lossless fashion. Uniquely identifiable flow control transmit on/off ("XON/XOFF") messages are transmitted, preferably during IPG, by a receiving station about to be congested to the transmitting station whose data output is to be controlled. The transmitting station physical layer receives and decodes these messages. If XOFF is recognized, the transmitting station continuously asserts CRS to its MAC layer at the MII, regardless of the prior CRS current state. CRS is continuously asserted until the receiving station transmits an XON flow control signal, indicating its ability to accept further data. During CRS assertion, the transmitting station defers transmission, e.g., is flow controlled. The MAC layer is slightly modified (but is still backward compatible with half-duplex networks) to provide separate transmit deferral receive data frame mechanisms using separate and independent input status signals, namely CRS and RX.sub.

Abstract: Three-dimensional compressed geometry is decompressed with a unit having an input FIFO receiving compressed data bits and outputting to an input block state machine and an input block, whose outputs are coupled to a barrel shifter unit. Input block output also is input to Huffman tables that output to the state machine. The state machine output also is coupled to a data path controller whose output is coupled to a tag decoder, and to a normal processor receiving output from the barrel shifter unit. The decompressor unit also includes a position/color processor that receives output from the barrel shifter unit. Outputs from the normal processor and position/color processor are multiplexed to a format converter. For instructions in the data stream that generate output to the format converter, the decompression unit generates a tag sent to the tag decoder in parallel with bits for normals that are sent to the format converter.

Abstract: A fiber optic cable is provided with a thermal shield which consists (proceeding outward from the cable) of a temperature insulating layer of a foam plastic such as polyethylene, a plastic film wrap such as aluminized nylon, a metallic braid such as tinned copper and an outer jacket of plastic as additional temperature insulation and to facilitate pulling the cable. The film wrap and outer jacket are optional. For further shielding a second layer of foam plastic may be positioned outside the first metallic braid followed by a second plastic film wrap, a second metallic braid and an outer plastic jacket. If the shielded cable is near a source of heat, such as a hot water pipe or an air conditioning duct, the fiber optic cable temperature is uniform throughout its cross-section. Without the thermal shield instability of the signals in different fibers may occur because of heat differential.

Abstract: A method of controlling a microprocessor to transform unsigned data to a signed format so that the unsigned data can be processed by signed instructions. In particular, a subtraction between two unsigned numbers can be transformed into a subtraction between two signed numbers.

Abstract: In a printer, periodic testing of printer ink density occurs once the number of print operations exceeds a particular threshold. The threshold is either determined from use or from statistics which summarize the performance of a particular manufacturer and ink supply. Testing results are reported to a maintenance facility and to an MIS application over a network or over a point to point link. Local warnings may be given that the ink supply is low and double printing may be used to darken the printed product until the ink supply is changed.

Abstract: A method of producing a sequence of triangles from a compressed geometry stream that includes an array of vertices includes steps of parsing vertices and pushing the parsed vertices into a buffer until the last vertex of the current row of the array is parsed and pushed. The first vertex of the current row is then re-used from the buffer and drawn. The first vertex of the next row is then parsed from the geometry stream, pushed into the buffer and drawn. Thereafter, it is determined whether a quad split bit is asserted. If the quad split bit is not asserted, the next vertex from the current row is parsed, pushed into the buffer, and drawn. The next vertex of the previous row is then re-used from the buffer and the re-used next vertex is drawn. If the quad split bit is asserted, the next vertex of the previous row is re-used from the buffer and drawn. The next vertex from the current row is then parsed and pushed into the buffer.

Abstract: A system, method and computer program product for compiling a source file and to generate a data structure associating a global symbol with a global register referenced in the source file. The data structure enables a linker to initialize the global registers. The compiler also generates an object file from the source file. The object file includes the global register information. A linker links the object file potentially with at least one other object file or shared library to thereby generate an executable file or shared library. The linker uses the global symbol information contained in the object file to initialize the global registers and to perform relocation operations.

Abstract: A bus snooping multimedia subsystem for implementing video multicast transactions. A multimedia data source such as a video input digitizer is coupled to an expansion bus of a computer system. A plurality of multimedia destination subsystems are further coupled to the expansion bus, such as a video accelerator card and a video compression device, among others. At least one of the destination subsystems is configured to implement a snooping mode of operation wherein transactions effectuated upon the expansion bus are monitored. The snooping destination subsystem may include a programmable storage unit to allow the device to be programmed with specified addresses (or address ranges). The programmed address information associated with the storage unit may correspond to addresses mapped to another destination subsystem in the computer system.

Abstract: A system for facilitating determination of accurate timing of execution of a computer program fragment by a digital computer comprises a clock resolution determination subsystem and an iteration number determination subsystem. The clock resolution determination subsystem determines a clock resolution value representing a resolution of a clock provided by the digital computer. The iteration number determination subsystem uses the clock resolution value, and maximum and minimum desired time interval values, to determine an iteration number value, the iteration number representing a number of iterations for execution of the computer program fragment to provide accurate timing of the computer program fragment by the digital computer.

Abstract: Apparatus, methods, and computer program products are disclosed for optimizing programs containing single basic block natural loops with a determinable number of iterations. The invention optimizes, for execution speed, such program loops containing statements that are initially variant, but stabilize and become invariant after some number of iterations of the loop. The invention optimizes the loop by unwinding iterations from the loop for which the statements are variant, and by hoisting the stabilized statement from subsequent iterations of the loop.

Abstract: A method and apparatus for generating additional implicit keys from a key [K.sub.ij ].sub.N without the necessity of generating a new Diffie-Helman (DH) certificate or requiring communication between nodes to change implicit master keys is disclosed. A first data processing device (node I) is coupled to a private network which is in turn coupled to the Internet. A second data processing device (node J) is coupled to the same, or to a different network, which is also coupled to the Internet, such that node I communicates with node J using the Internet protocol. Node I is provided with a secret value i and a public value. Data packets (referred to as "datagrams") are encrypted to enhance network security. Each node maintains an internal value of N which is incremented based on time and upon the receipt of a data packet from another node. The key [K.sub.ij ].sub.N.sbsb.i is derived from the appropriate quantity of .varies..sup.Nij by using high order key-sized bits of the respective quantity.

Abstract: A method and apparatus for handling alpha premultiplication is described. In an embodiment, image data is contained within an instance of an image object that also contains a state variable indicating whether the image data is currently premultiplied or non-premultiplied. A method within the image object responds to requests to coerce the image data into a desired or destination premultiplication state. Based on the value of the state variable, the method multiplies or divides the image data components by the alpha component, or does nothing. The state variable is updated to reflect any change in the premultiplication state of the image data. In one embodiment, the image object is implemented as a buffered image object instance containing a tile object instance and a color model object instance. The tile object instance maintains a reference to a data array(s) containing the image data file, and provides methods for inserting and extracting pixel data from the data array(s).