Abstract: A new register test system and method is provided for testing a register. The register under test has a number of bit storage locations, each of which is associated with one of a plurality of categories, including, for example, a read/write category, a read-only category, a write-only category, an always-"1" category and an always-"0" category. In accordance with the method, in each of a plurality of iterations, a data word is generated, stored it in the register under test, and thereafter retrieved from the register. For each iteration, an expected pattern is generated for comparison to the retrieved contents, using the original data, the retrieved contents and a plurality of mask patterns each associated with one of the categories. The expected pattern is compared to the pattern of the contents retrieved from the register and whether the register is deemed to be operating properly can be determined by whether the expected pattern corresponds to the retrieved pattern.

Abstract: A digital data storage subsystem comprises a cache memory, a digital data store and a host adapter. The cache memory includes a plurality of cache slots, each of which caches digital data from the digital data store for access by the host adapter. The digital data store includes a disk drive, in which data is stored in the form of variable- or fixed-length records. The storage controller identifies one of said data storage sections as constituting a current owner of respective ones of the cache slot, and is responsive to record staging requests to selectively transfer records from the data storage section identified as the owner of said at least one cache slot to said cache slot for caching. In staging records for the current owner, the storage controller may, but need not, over-write records that were previously staged in the cache slot for previous owners.

Abstract: A data visualization arrangement facilitates the display of a selected region of a multi-dimensional data object in a selected one of a plurality of display modes. The arrangement comprises a data object store, an interface, an object region retrieval component and a display. The data object store stores the data object, the data object comprising a plurality of data items in a predetermined organization. The interface receives a region identification for identifying a particular region of the object and a display mode identification. The object region retrieval component retrieves data items from a region of the data object as identified by the region identification received by the interface. Finally, the display receives the data items as retrieved by the object region retrieval mechanism and displays them in the display mode as identified by the display mode identification.

Abstract: In brief summary, the invention provides a new message packet transfer system, which may be used in, for example, a multiprocessor computer system. The message packet transfer system comprises a plurality of switching nodes interconnected by communication links to define at least one cyclical packet transfer path having a predetermined diameter. The switching nodes may be connected to, for example, digital data processors and memory to form processing nodes in an multiprocessor computer system, and/or to other sources and destinations for digital data contained in the message packets. The switching nodes transfer message packets each from a respective one of the switching nodes as a respective source switching node to a respective one of the switching nodes as a respective destination switching node.

Abstract: A communications driver is provided for establishing communications sessions between a computer system and a remote device, such as another computer system. The computer system includes a plurality of ports which are connected to a number of diverse types of communications media. At least one of the ports comprises a network port controlled by a network socket driver, so that the communications driver can be used in connection with lower-level networking drivers which may be provided by a variety of manufacturers. The communications driver selectively establishes a communications session such that the computer system will operate as a terminal with the remote device over one of the communications media, as selected by an operator. The communications driver initially enables the operator to identify a communications medium and a remote device, and the driver thereafter selects one of the ports in response to identification by the operator of a communications medium and a remote device.

Abstract: New face masks protect a wearer's eyes against impact by a projectile or the like. In one aspect, the face mask comprising a plurality of frames, each of which is adapted to fit onto the wearer's face around one of the wearer's respective eyes, with each frame having mounted thereon a bar arrangement comprising a plurality of generally vertically directed protective bars. The bars are variably spaced in a horizontal direction and mounted into the respective frames so as to avoid obscuring the wearer's vision in any direction of the wearer's field of vision when both frames mounted onto the wearer's face. A "frame mounting arrangement," which in one embodiment includes a nose guard that is mounted between the frames to be situated over the wearer's nose, and a strap attached to both frames to extend behind the wearer's head, holds both the frames onto the wearer's face such that one of the frames is fitted around one of the wearer's eyes.

Abstract: Interconnection subsystems having diverse topologies are disclosed for interconnecting small numbers of nodes having a predetermined maximum degree in a multiprocessor computer system. The interconnection subsystems are generally classified into three diverse classes of topologies, including a "polygonal" class, a "ladder" class and a "tiled" class. In topologies of the polygonal class, a majority of the nodes in the multiprocessor computer system are connected in a ring and the remaining nodes are connected to the nodes in the ring, and in some cases also to each other. In topologies of the ladder class, the nodes are interconnected in a "ladder" topology comprising a series of nodes connected in a ring, the ring corresponding to one standard of a ladder topology folded on itself. Each node in the ring is connected to another node in a second series, effectively forming rungs of the ladder topology.

Abstract: A computer system includes a information type source file, an information value file and a dynamic dialog box processor. The information type source file includes a plurality of text entries in, for example, ASCII text form, which can be easily edited by an operator. The information value file includes a plurality of value entries each for storing a value used in other processing by the computer system. The dynamic dialog box processor uses the text entries from the information type source file to generate a dialog box for display to an operator, and receives information values provided by an operator in connection with respective information text entries to update the values in the value entries in the information value file. Since the ASCII text entries in the information type source file can be easily edited, the particular types of information to be provided through the dynamic dialog box can be easily modified by the operator with a minimum of programming and debugging effort.

Abstract: A programmable clock circuit generates a real time clock value, which is incremented in response to a real time clock increment signal. The real time clock increment signal is generated after a selected number of ticks of a system clock signal, with the number of ticks being determined by whether it is operating in a normal mode or an error compensation mode. In the normal mode, the real time clock increment signal is generated after a selected number of ticks of the system clock signal, which results in an increasing cumulative timing error. In the error compensation mode, the real time clock increment signal will be generated after a number of ticks of the system clock signal selected so as to reduce this cumulative error. The programmable clock circuit keeps track of the cumulative error in the real time clock signal while operating in the normal mode.

Abstract: A fingerprint generating system generates a fingerprint value for an object in an object-oriented programming arrangement. The object comprises a digital information stream and the fingerprint generating system generates a fixed-length fingerprint value from the digital information stream. The fingerprint generating system receives the digital information stream comprising the object and processes the digital information stream in accordance with a selected hash value generating algorithm to generate a hash value which comprises the fingerprint value. The hash value generating algorithm is selected from a class of hash value generating algorithms characterized in that:i. in response to said input digital information stream, a digital hash value having a predetermined number of digital bits will be generated as an output;ii.

Abstract: A fault-tolerant computer system comprises a plurality of processing nodes and a plurality of storage nodes interconnected by a network. The processing nodes perform processing operations in connection with user-generated processing requests. The processing nodes, in connection with processing a processing request, generate storage and retrieval requests for transmission to the storage node to enable storage of data thereon and retrieval of data therefrom. The storage nodes store data in at least one replicated partition group comprising a plurality of replicated partitions distributed across the storage nodes. A storage node, on receiving a retrieval request from a processing node provide the requested data to the processing node. In addition, on receiving a storage request from a processing node, a storage node initiates an update operation to update all of the replicated partitions in the replicated partition group.

Abstract: A digital data processing system comprises a host information generating device, a mass storage subsystem, and a back-up information storage subsystem. The host information generating device generates information and provides it to the mass storage subsystem for storage. The mass storage subsystem receives and stores the generated information from the host information generating device and transfers the generated information to the storage element for storage, and further transfers the generated information to the back-up information storage subsystem. The back-up information storage subsystem receives and stores the generated information from the mass storage subsystem's storage subsystem receives and stores the generated information from control element. The back-up information storage subsystem includes a filter/buffer module, a tape log module and a reconstruction module.

Abstract: A debugger for use in connection with a parallel computer including a plurality of processing nodes. The debugger enables the operator to establish a processing node set in response to certain criteria, such as the respective identifications of the processing node and their prior processing under the debugger. The debugger, in response to a processing node set establishment command from the operator, enables each processing node to establish and condition a set membership flag in response to the operator-supplied set membership criteria. The debugger is then responsive to a debugging command from the operator to enable the processing nodes to use their respective set membership flags to condition their execution of the debugging command.

Abstract: A communication subsystem for a digital computer system, which processes application programs under a base operating system (such as the MS-DOS operating system) in a first processor operational mode (such as the V86 mode), and also under an enhanced operating system (such as Microsoft Windows) during a session under a second processor operational mode (such as a privileged or user mode). During an enhanced operating system session, the enhanced operating system makes use of at least some selected elements of the base operating system, in particular relation to the current invention some of the communications drivers. The communication subsystem enables the digital computer system to transfer messages, each comprising a series of characters, over a communications network.

Abstract: An information transfer system transfers information, in the form of at least one digital data word, from an source operating in a first clock signal domain defined by a first clock signal, to a destination operating in a second clock signal domain defined by a second clock signal. The information transfer system includes a buffer, a buffer storage element, a buffer retrieval element and a synchronizer. The buffer storage element stores the data word in the buffer under control of a data word present indication, and the buffer retrieval element retrieves the data word from the buffer under control of the second clock signal and a synchronized data word present indication. The synchronizer generates the synchronized data word present indication in response to the first clock signal, the second clock signal, and the data word present indication, thereby to synchronize the data word present indication from the first clock signal domain into the second clock signal domain.

Abstract: A computer system comprises a plurality of programs, each operating in an operating area such as a virtual machine. The programs are provided with a common data buffer for buffering data for processing by said programs. Each program also has a buffer control including at least one pointer for pointing to a buffer containing data to be processed by the program. One of the programs will initially process the data in the common data buffer and, after it is finished processing, will control the other program's buffer pointer to enable the other program to process the data in the common data buffer. By using the same buffer to contain data to be processed by both programs, the programs can avoid having to copy the data between private buffers maintained for each, which can assist in accelerating through-put by the computer system.

Abstract: A network navigation and viewing system is disclosed for use in managing a network. The network includes a plurality of digital devices interconnected by communication links in at least one domain, with each device having a device identifier and each domain having a domain identifier. The network navigation and viewing system facilitates generation of a graphical image depicting a logical organization of the network. The network navigation and viewing system in one aspect retrieving device identifier and domain identifier information for the devices connected in the network and uses them to generate a network organization graphical image for display to an operator, the image comprising a plurality of icons each representing a device, with the icons being aggregated in the network organization graphical image by domain thereby to depict the logical organization of the network.

Abstract: A digital computer system comprises a precise exception handling processor and a control subsystem. The precise exception handling processor performs processing operations under control of instructions. The precise exception handling processor is constructed in accordance with a precise exception handling model, in which, if an exception condition is detected in connection with an instruction, the exception condition is processed in connection with the instruction. The precise exception handling processor further includes a pending exception indicator having a pending exception indication state and a no pending exception indication state. The control subsystem provides a series of instructions to the precise exception handling processor to facilitate emulation of at least one emulated program instruction.

Abstract: A digital data processing system comprises a host information generating device, a mass storage subsystem, and a back-up information storage subsystem. The host information generating device generates information and provides it to the mass storage subsystem for storage. The mass storage subsystem receives the generated information from the host information generating device and transfers the generated information to the storage element for storage, and further transfers the generated information to the back-up information storage subsystem. The back-up information storage subsystem receives and stores the generated information from the mass storage subsystem's control element. The back-up information storage subsystem includes a filter/buffer module, a tape log module and a reconstruction module. The filter/buffer module filters and buffers the information received from the mass storage subsystem and provides the buffered information to the tape log module for storage.