Abstract: A search mechanism improves the performance of a queue system including a queue for storing a plurality of data items and search mechanism by maintaining a key cache data structure having an array of entries, each of which have a key field and a pointer field. The key and pointer fields respectively of each cache entry are used for storing a key value of a different one of the enqueued data items of the queue and a pointer to that enqueued item. The key of each data item to be enqueued is used to generate an index value for accessing a location of the key cache array to obtain immediate access to the corresponding enqueued data item thereby reducing the search time for determining the proper point within the queue for inserting the data item to be added.

Abstract: The emulation of a first system disk drive on a second processing system including a second system user level process including first system user and executive tasks issuing disk input/output requests. An emulator level is interposed between the second system user level process and a kernel level and includes a pseudo device driver corresponding to the first system disk drive and the kernel level includes a kernel process corresponding to the pseudo device driver and emulating the disk drive. The pseudo device driver and the kernel process execute in a second system process to emulate the operations of the disk drive and the kernel process emulating the disk drive is a file input/output process. The pseudo device driver includes a pseudo device queue, a return queue and a queue manager responsive to first system disk input/output instructions and to completed disk operations.

Abstract: An emulator executes on a second data processing system as a second system user level process including a first system user level program, a first system executive program, and first system user and executive tasks. An emulator level is interposed between the second system user level process and a kernel level and contains pseudo device drivers. Each pseudo device driver corresponds to a first system input/output device. The kernel level includes kernel processes, each kernel process corresponding to a pseudo device driver. The second system hardware platform includes a plurality of second system input/output devices, wherein each second system input output device corresponds to a kernel process. Each combination of a pseudo device driver, a corresponding kernel process and a corresponding second system input/output device executes in a second system process and emulates the operations of a corresponding first system input/output task and the corresponding first system input/output device.

Abstract: The present invention which makes use of knowledge developed at the program writing stage by the programmer or by software tools such as a compiler that some substantial number of data accesses would miss in the cache hierarchy to the detriment of performance and that it would be possible to prefetch the necessary data in parallel with performing useful work. The invention provides a background memory move (BMM) mechanism by which the program can specify such prefetching of data from main memory to a quickly-accessible data cache and by which the program can determine which such prefetches have completed. This mechanism makes it possible to improve the performance of the computer system through the effective use of added concurrency while avoiding the overheads of process-swapping.

Abstract: A method and apparatus provides an analog mode of operation of a standard test access bus interface based on a standard boundary scan architecture which is limited to use of digital signals. Circuits are included in the interface which enable the sharing of control paths at separate time intervals defined under instruction control for processing analog and digital signals thereby providing a hybrid capability without any increase in the number of lines required by the interface.

Abstract: In order to provide communication between two processors in a data processing system, a target processor includes apparatus that can store data signal groups from a source processor. Having stored a data signal group from the source processor, the target processor notifies the source processor of the receipt of the data signal group. In response to the presence of the stored data signal group, the target processor executes a interprocessor command or instruction identified by the transferred data signal group. The source processor at a preselected time, executes an instruction to determine if the command designated by the data signal group stored in the target processor has been executed. The commands specified by the transferred data signal groups can be executed under hardware control by the target processor in a relatively short time immediately following completion of the instruction in execution in the target processor at the time of the transfer of the data signal group.

Abstract: An ESD protection system which shields PCAs during the assembly process comprises transportable support means for holding an ESD bag in a predetermined position which is convenient both for the insertion and extraction of a PCA(s) and for observing stored PCA(s), thus ensuring proper handling. The system has first and second attachment means for attaching the ESD bag to the frame and for holding papers associated with the PCA(s) outside the ESD bag and for providing the weight necessary for maintaining a sealing fold in the bag whenever the PCA(s) are enclosed therein. The transportable support means is a frame which is constructed to mate with a rack designed for accommodating a plurality of frames. When so mated, the rack provides the desired level of stability and orderly positioning of a desired number of frames spaced apart such that the ESD bags attached to the frames may be easily observed for correct loading, closure and paperwork processing.

Abstract: A database system provides a manufacturing factory environment which integrates a plurality of manufacturing processes used to control the manufacture of a number of electronic board products on a plurality of manufacturing lines. The database system responds to operator initiated commands and provides a predetermined number of control table structures in memory for storing predetermined types of control parameter entries used in controlling the manufacturing processes. The database system includes a number of control mechanisms which in response to operator commands perform sequences of operation for enabling process steps to be added, applied or linked to other processes or modified in a reliable and efficient manner.

Abstract: A software implemented control mechanism is used in a test system for assigning unique pre-established electronic addresses which are to be written into the memory elements of printed circuit boards during the manufacture thereof. Each PCB is previously encoded with a scannable board serial number label, and the test system includes a processing unit and a memory configured for storing test software for testing PCBs. The control mechanism is incorporated into the test software which when installed into the test system configures the system's memory for assigning electronic addresses. The control mechanism includes first and second sets of tables containing entries which define the ranges of valid serial numbers and preallocated electronic addresses.

Abstract: A local host data processing system operating under the control of a local host operating system includes components of multiple emulating hosted operating systems. The host operating system further include a TCP/IP network protocol stack which couples to the communications facilities of the host system connected to a local area network for communicating with a number of remote host systems. Host and hosted operating systems share the same TCP/IP network protocol stack. A virtual network mechanism is configured within the local host system to be operatively coupled to the host network protocol stack and provide access to well-known port application programs. When so configured, the mechanism functions as another LAN to which multiple virtual host systems are attached for executing applications under control of the emulating hosted operating systems.

Abstract: A host data processing system operating under the control of a host operating system such as an enhanced version of the UNIX operating system on a RISC based hardware platform includes an emulator which runs as an application process for executing emulated system (ES) user application programs. The emulator includes a number of emulated system executive service components including a socket command handler unit and a socket library component operating in shared memory and an interpreter, an emulator monitor call unit (EMCU) and a number of server components operating in host memory. The host operating system further includes a host socket library interface layer (API) which operatively connects through a TCP/IP network protocol stack to the communications facilities of the hardware platform. The socket server components operatively connect ES TCP/IP application programs to the socket library interface layer of the host operating system when such application programs issue standard ES socket library calls.

Abstract: An application such as an interpretative emulator executes a wide range of different classes of emulated program instructions developed for the processor architecture being emulated on a host system which includes an dual integer pipelined execution unit. The sets of RISC instructions which execute emulated program instructions are organized within the emulator so as to be processed as two distinct instruction streams by the dual integer pipelined execution units wherein one of the pipelined unit performs the steps necessary to completing a current or foreground like operation on each emulated program instruction while the other pipelined unit performs the steps of an anticipated lookahead or background like operation on the next emulated program instruction.

Abstract: A host data processing system which includes a plurality of input/output devices operates under the control of an enhanced version of the UNIX operating system. The host system includes an emulator which runs as an application process for executing user emulated system (ES) application programs. The emulator includes a number of emulated system executive service components operating in shared memory and an interpreter, an emulator monitor call unit (EMCU) and a number of server facilities operating in the host memory. The ES executive service command handler component is extended to accommodate a number of dual decor commands which invoke host system facilities to execute terminal based commands either synchronously or asynchronously through the automatic creation of host shell mechanisms directly accessible by emulated system users. The server facilities include a network terminal driver (NTD) server for executing emulated system user terminal requests through host system drivers.

Abstract: A host data processing system which includes a plurality of input/output devices operates under the control of an enhanced version of the UNIX operating system. The host system includes an emulator which runs as an application process for executing user emulated system (ES) application programs. The emulator includes a number of emulated system executive service components operating in shared memory and an interpreter, an emulator monitor call unit (EMCU) and a network terminal driver (NTD) component operating in the host memory. Configuration command means are provided for initially configuring a host terminal to operate in a plurality of asynchronous driver (ATD) modes implemented by the NTD component. When a terminal has been configured by a user to run applications written for the ATD driver, it sets a mode indication which causes the NTD component to respond to user applications as an ATD driver and determine if each ATD request can be carried out with functionality included within the NTD component.

Abstract: A remote service facility (RSF) unit is integrated into the operating system of the host system being supported. The RSF unit utilizes a standard generic menu interface system (GMIS) unit through which a user can enter different types of commands which results in the display of a number of menu sequences for configuring how the different independently controllable components of the RSF unit will operate in performing remote support functions. The components include a problem detection and reaction component, a system action component and a callback component, each of which operatively couple to the GMIS unit. The components are integrated in a predetermined manner so that collectively, they carry out remote support according to the way in which they were configured.

Abstract: A host data processing system which includes a plurality of input/output devices operates under the control of an enhanced version of the UNIX operating system. The host system includes an emulator which runs as an application process for executing user emulated system (ES) application programs. The emulator includes a number of emulated system executive service components operating in shared memory and an interpreter, an emulator monitor call unit (EMCU) and a number of server facilities operating in the host memory. The ES executive service components are extended to accommodate a number of dual decor commands and functions which make host system facilities directly available to ES application programs by concurrent execution of program operations within both the emulator and host system environments. The EMCU includes mechanisms for performing an initial level security validation operation which allows subsequent trusted verification of user identity when dual decor commands or functions are invoked.

Abstract: A multiprocessor computer system includes a number of processors, each processor having an interrupt mechanism and connecting in common to a system bus over which interrupt requests are communicated. When a processor accepts an interrupt request from another processor, it generates an acknowledge response on the system bus. If such processor contains a previous and pending interrupt request of an equal or higher priority level, it generates a not acknowledge response on the system bus and refuses the interrupt request. At the completion of servicing an interrupt request, each processor places on the system bus, an interrupt completed command including an address identifying such processor, a code designating a priority level to which it has switched and a code indicating that the processor has completing servicing an interrupt request.

Abstract: A local host data processing system operating under the control of a local host operating system includes components of a hosted operating system. The host operating system further include a TCP/IP network protocol stack which couples to the communications facilities of the host system connected to a local area network for communicating with a number of remote host systems. Host and hosted operating systems share the same TCP/IP network protocol stack. A virtual network mechanism is configured within the local host system to be operatively coupled to the host network protocol stack and provide access to well-known port application programs. When so configured, the mechanism functions as another LAN to which the hosted operating system is attached. The mechanism transforms the well-known port identifier of each inbound packet into a non-well-known port identifier in addition to other station address identifier fields.

Abstract: A layered communications bridge mechanism connected between an upper communications layer of a first communications layer mechanism executing in a user level process and a layered communication kernel process of a second system corresponding to the next lower layers of the first communications layer mechanism. The bridge includes an upper bridge mechanism operating to appear to the lowest layer or the layers of the first communications layer mechanism to be the next lower layer of the first layered communications mechanism and a lower bridge mechanism operating to appear to the upper communications layer of the second system kernel process to be the next higher layer of the communications layers of the second system and the upper and lower bridge mechanisms operate to map between the operations of the lower layer of the first communications layer mechanism and the upper layer of the layered communications layers of the second system.

Abstract: A single device dual action lead forming tool uses standard long nose pliers as the basis of its construction. A set of lead forming elements is incorporated into each plier jaw element. Each set contains forming tooth and forming receptacle elements positioned adjacent to one another in a predetermined manner. The elements of one set are arranged within one jaw element in a reverse order relative to the arrangement of lead forming elements in the other jaw element. When the jaw elements are closed, pairs of like positioned forming tooth and receptacle elements of both sets cooperate together to form both the inner and other leads of a single electronic component in a single operation.