Abstract: The subject channel interface circuit functions in a multiprocessor environment to provide a high speed interface between a processor and the communication channel which interconnects all the processors. The communication channel carries data messages, which messages contain a header field specifying source, destination and control information. The subject channel interface circuit is programmable and serves to dynamically translate the header portion of the data message as it is received and thereby determine whether this data message is to be stored in the processor memory. If the data message is to be stored, the channel interface circuit immediately converts the header field into a hardware address, which is used to activate a specific location in processor memory. The data message is then inputted (via DMA) to this memory location and the appropriate buffer pointers are reset.

Abstract: A communication system is arranged having a special hold mode (called parkhold) where a station may place any conference connection associated with that station in the parkhold mode. Any station in the system may, by transmitting a certain signal, become connected to any parked conference without regard to whether that staton has an appearance of the parked line. Selectivity is provided in that each conference is parked on a separate link and the recall signal identifies the link of any particular parked conference. This arrangement can be used for call transfer, meet-me-conferencing as well as for allowing mobility between stations in retrieving a call from the parkhold mode.

Abstract: An optically toggled bidirectional normally-on switch is provided with protection against bilateral voltage and bidirectional current surges by the inclusion of a pair of oppositely poled thyristors. One version uses a large junction-type field-effect transistor in its main path and a pair of smaller junction-type transistors in the subsidiary path. A photodiode array controls the gate voltage on each of the transistors and turns them off when illuminated. A control node in the subsidiary path is connected to the gates of the SCRs so that excess current in this path turns on the appropriately-poled thyristor to provide an additional shunt path for the current.

Abstract: A new tool for assembling stackable elements with multiple conductors is disclosed. The new tool consists of a connector holding bracket 101 for retaining the elements and conductors, a T-bar assembly 120 for applying forces to cut conductors and press stackable elements together, and a support assembly 105 which includes a hydraulic system which positions the T-bar assembly 120.

Abstract: A detector circuit for detecting the on-hook and off-hook states of a communication line includes current and voltage sensors for generating two reference signals. One signal represents the current flowing in the line; the other represents the voltage on the line. A comparator circuit compares these two references to generate an output signal representative of the on-hook state when the magnitude of one of the references is greater than the other. When the magnitude of the one reference signal is less than the other, the comparator circuit generates another output signal representative of the off-hook state of the line. In addition, when the line is electrically isolated from ground, the two comparator output signals may drive an opto-isolator to generate two corresponding output signals electrically isolated from the comparator output signals.

Abstract: A secondary lithium battery system which operates at ambient temperatures. The battery includes an organic solvent for an electrolyte, a conventional cathode, and an intercalation compound for an anode. Such batteries maintain high capacities after numerous discharge-charge cycles.

Abstract: A normally OFF linear bilateral switch using two VMOS FETs is described. The conduction state of the two VMOS FETs is controlled by a photodiode array optically coupled to a light emitting diode. A break-before-make switch may be constructed using this switch together with a normally ON JFET.

Abstract: Iron oxide films for "see-through" photomasks are deposited upon heated substrates by chemical vapor deposition from iron pentacarbonyl in the presence of oxygen. The solubility of the iron oxide film is found to be higher, the lower the temperature of the substrate during deposition. At temperatures below 160 degrees C., films are obtained which can be patterned at reasonable rates by photolithographic procedures using conventional mild etchants.

Abstract: Highly directional response patterns can be obtained by connecting microphones or loudspeakers with tubular coupling path structures. The coupling paths comprise a plurality of elements (110,111 . . . 157) arranged in pairs (110,111; 112,113; . . . 156,157) so that for every element (110) below a center line (102) there is an element (111) above the line. Furthermore, the relationship between the element pairs is nonlinear. The desired directional response comprises one main lobe and a plurality of substantially smaller lobes below a determinable threshold value. The elements may be a bundle of tubes (90) or a plurality of apertures (110,111, . . . 157) in a single tube (100).

Abstract: An electrical-optical interface network for use in a carrier-sense, multiple-access system with collision-detection provides two-way transmission between an electrical circuit (5,7,9) and a pair of lightguides (21,22), but prevents signal transmission between the lightguides.

Abstract: The disclosed communication system operating mode signaling method and arrangement utilizes dc current signaling over the loop facility connecting a customer to a central office (CO). The dc current on the facility provides concurrent on-hook/off-hook signaling and voice/digital data operating mode signaling between the customer and CO. A current flow in a first direction over the facility signals a voice operating mode while a current flow in a second direction signals a digital data operating mode. A customer signals a change in the operating mode by reversing the direction of allowed current flow at the customer unit. The resulting interruption of the current flow is detected at the CO which responds by reversing the direction of current flow over the facility. The reappearance of current flow over the facility distinguishes a customer's change in operating mode from an on-hook condition.

Abstract: A process employing bodies that are fabricated to have a specific configuration are useful for the storage of information such as digital data. In one embodiment a material, such as germanium, is etched to produce a structure having a multiplicity of columnar or conical features. By providing a sufficient number of these features per unit area, it is possible to store at a relatively high density a variety of information. This information storage is accomplished by melting the columns or cones in a localized area. If these structures are of the appropriate size and spacing, they appear optically absorbing before melting and a reflective region appears in the treated area. In this manner archival storage of densely packed information is possible.

Abstract: An improved architecture for a single chip microprocessor CPU includes provision for directly observing at its terminals the control signals from its instruction decoder to facilitate functional testing of the chip. The CPU, upon receiving a command signal transfers the signals on the control lines of its instruction decoder to its output terminals. In one embodiment of the invention the command signal is applied to the CPU chip at a designated input terminal. In another embodiment, the command signal is applied through a special instruction. The improvements permit increased functional test fault coverage and shorter test programs.

Abstract: A simple method for increasing the dynamic range of a GaAs FET amplifier is described. The drain resistance of the FET is adjusted to induce leakage current across the gate-source junction when excessive power levels are imposed on the gate. This current shunt is provided without added circuit components and therefore does not affect the sensitivity or bandwidth performance of the amplifier.

Abstract: Magnetically actuated devices such as, e.g., switches and synchronizers typically comprise a magnetically semihard component having a square B-H hysteresis loop and high remanent induction. Among known alloys having such properties are Co-Fe-V, Co-Fe-Nb, and Co-Fe-Ni-Al-Ti alloys which, however, contain undesirably large amounts of cobalt.According to the invention, devices are equipped with a magnetically semihard, high-remanence Fe-Cr-Mo alloy which comprises Cr in a preferred amount in the range of 6-26 weight percent and Mo in a preferred amount in the range of 1-12 weight percent. Preparation of alloys of the invention may be a treatment of annealing, deformation, and aging.Magnets made from alloys of the invention may be shaped, e.g., by cold drawing, rolling, bending, or flattening and may be used in devices such as, e.g., electrical contact switches, hysteresis motors, and other magnetically actuated devices.

Abstract: A series of words each representing one of at least M (M.gtoreq.3) different values is encoded by grouping the words into alternate runs of (1) a first, frequently occurring value, and (2) all other values. A coded representation of each run length as well as a representation of the non-frequent values which make up every other run are then combined in a predetermined sequence. Different code tables may be used to generate code words for each type of information.

Abstract: A system for generating a drift-free three-level pulse signal from a two-level input signal involves an improvement over prior art in that output transformers are eliminated. This system is compatible with integrated circuit techniques using solid state logic elements in conjunction with a capacitor-resistor combination at the output.

Abstract: Yttrium-iron magnetic domain materials having bismuth ions on dodecahedral sites are suitable for the manufacture of high-density, high-speed magnetic domain devices for operation at high and especially at very low temperatures. In these devices magnetic domain velocity is greater than 2000 centimeters per second per oersted, and magnetic domain diameter is less than 3 micrometers. A specified operational temperature range may extend from -150 to 150 degrees C.; accordingly, such devices are particularly suitable for operation aboard satellites, e.g., in satellite communications systems.