Abstract: A real time graphic processor is disclosed which processes graphic cell specifications on a scan line-by-line basis to generate pixel data. The pixel data from each cell specification is assembled to form a completed scan line of pixel data which is used to modulate a printing element, such as a laser diode. The invented graphic processor contains a special purpose cell specification processor which, in addition to generating the pixel data, modifies the cell specification by substituting new horizontal location and cell height indicator values. The modified graphic cell specification is then recirculated to the cell specification processor memory for processing the next scan line.

Abstract: Disclosed is a processor and method for the real time generation of linear arrays of pixel data. The generated pixel data is used to modulate a laser diode as it scans across a printing medium, thereby producing printed font and logo characters.In accordance with the present invention, the real time processor receives a series of cell specifications on a scan line-by-scan line basis, the cell specifications identifying the font type and placement information. The real-time processor uses this information to access from its font memory a linear array of pixel data corresponding to the identified font type. The accessed pixel data is used to modulate the laser diode as it scans the printing medium line-by-line. Thus, as the laser diode is modulated by the pixel's "ones" and "zeros", it is pulsed "off" and "on", thereby generating pixel dots on the print medium itself or on a photosensitive drum which subsequently prints an image on a page through an electrostatic process.

Abstract: In a continuous printing plant a timer unit is provided with indication whenever a first control is operated to supply power to the printing plant and whenever a second control is operated to inch a new batch of paper into the printer. The timer unit commences a first timing operation of a first predetermined period whenever indication is received from the first or second controls and switches off power to the entire printer if no reset signal is received within the first predetermined period. A sensor detects the movement of a printed paper web between the printer and a set of takeup rollers and indicates the movement to the timer unit. The timer unit initiates a second timing operation whenever it receives indication from the sensor and switches off power to the takeup rollers if indication is not received from the sensor or from the first and second controls within a second predetermined period, thereby independently switching off the takeup rollers in the event of a failure in the printer.

Abstract: A microcontroller for controlling a digital device which controller is formed of a plurality of control stores each of which is provided with a register counter to address different locations within corresponding control store. Each control store is accessed each clock cycle and an instruction register is provided to receive one of the fetched microinstructions from the selected control store. In this manner, a microinstruction is presented to the instruction register each clock cycle even though the previous microinstruction was a conditional branch, a jump to subroutine or a return to subroutine instruction. In order to accommodate jump to subroutine and corresponding return from subroutine instructions, the respective address of the return subroutine is stored in a push-down stack for presentation to a selected one of the above-referred-to register counters in an order the reverse of the order in which those addresses were placed on the top of the stack.

Abstract: In a rotating disc information storage system, a cover is designed to induct laminary airflow at the disc surface and to reduce the impurity level of the disc atmosphere. The laminar airflow results from the shape of the cover which closely conforms to the contours of the disc and its drive spindle and is closely spaced thereto. The impurity level is reduced by the spiral airflow produced by disc rotation being provided to a divergent filter duct and filter to capture airborn particles. The divergent filter duct and opening to the duct are formed between the cover and a wall around the periphery of the disc. The position of the wall is mechanically adjustable to control the spiral airflow into the filter duct. Air is filtered and returned to the disc storage system.

Abstract: Disclosed is a method and apparatus for the lowcost assembly of precision optical devices utilizing single or multiple bounces. The apparatus makes use of a precision machined alignment platform to support optical mirrors in precise alignment. A low cost holding structure is clamped over the alignment platform to position one of a plurality of connected sections adjacent to the back of each mirror. An adhesive is injected through holes provided in the holding structure adjacent to the back of each mirror. The adhesive bridges each mirror to the holding structure in a position corresponding exactly to the position of the mirrors on the alignment platform, thereby eliminating any need to adjust the mirrors for correct alignment.

Abstract: In a display panel comprising a gas-filled envelope containing at least two arrays of electrodes defining gas-filled cells, at least one array of electrodes is insulated from the gas and comprises A.C. electrodes. If the panel is turned off for any length of time with display information contained therein, the information can be re-displayed by applying special pulses during a re-ignition period and then applying normal sustaining pulses during the normal display period.

Abstract: Disclosed is an improved electrostatic ink jet printing system which provides a potential barrier to block static charges built up on a recording medium from influencing the electric field which draws a liquid imaging material from an ink jet nozzle to the recording medium. The system's ink jet nozzle is supplied with a liquid imaging material at a hydrostatic pressure such that a meniscus of the imaging material forms at the tip of the ink jet nozzle. A conductive platen is positioned in front of the exit oriface of the ink jet nozzle and the recording medium is interposed between the conductive platen and the tip of the ink jet nozzle. A potential difference is applied between the platen and the ink jet nozzle in order to generate the electric field. The potential barrier is effected by providing a conductive plate having an aperture between the recording member and the ink jet nozzle, the platen and plate maintained at an identical potential level.

Abstract: Disclosed is an energy detection circuit for use in a facsimile system autodialer/controller. The circuit monitors a telephone line and nulls out transmit tones leaving only receive signals. The analog receive signals are processed to produce a digital signal indicating the on-off times of receive energy on the telephone line. The energy on-off times may then be evaluated by a microprocessor included in the facsimile system autodialer/controller to determine whether a dial tone, busy signal or ring back is being received.

Abstract: This disclosure relates to a programmable unit employing plural levels of sub-instruction sets in addition to conventional instruction sets. The conventional level of instruction sets is employed to specify computational routines and other processing algorithms to be carried out by the unit. Each instruction in a conventional set is implemented in the unit by a sequence of first level sub-instructions which specify the various operations to be carried out within the unit which operations are comprised within the specific routine. In turn, the various first level sub-instructions are implemented by second level sub-instructions which specify the various control signals required to set the various gates as required for the particular unit operation to be carried out. With this hierarchy of sub-instruction sets, first level sub-instruction sets may be interchanged dynamically during the operation of the unit to dynamically change the processing capability of the unit.

Abstract: A method of allocating available bandwidth between stations configured in a write token controlled loop communications network. When a station desires to reserve additional bandwidth to itself, it captures the write token and transmits a bandwidth allocation token which includes a field indicating the originating station's amount of currently reserved bandwidth. Each station on the loop adds to the field the amount of its currently reserved bandwidth. When the allocation token arrives back at the originating station, the write token is regenerated and transmitted. If the total amount of currently reserved bandwidth indicated in the allocation token plus the desired additional bandwidth sought to be reserved is less than the allocatable bandwidth, then the reservation is granted. The additional bandwidth desired is then added to the total reserved by the originating station.

Abstract: The present disclosure describes an insulated electrical contact pin for use in making wiring changes in an interconnection medium such as a printed circuit board or backplane. More specifically, the present pin replaces the original compliant press-fit type pin mounted in a plated-through hole on the board. The pin is formed in two sections--one section having a threaded extremity, and the other, a tapped bore to receive the former. The pin is mounted in a plated-through hole on the printed wiring board by screwing the two sections together. Portions of the pin sections are electrically insulated from the wiring traces situated on or below the board surface. The present contact pin is versatile, easy to install and tolerance-free with respect to the dimensions of the plated-through hole in which it is mounted.

Abstract: The present disclosure describes a latch assembly wherein structural members are coupled to each other by an electric match-type device interposed therebetween. The latter device generally comprises a body portion having electrical connections thereto and a rigid mass of combustible material firmly adhered to an extremity thereof. At least a pair of the structural members are individually coupled to the combustible material. Remote activation of the match by the passage of electric current therethrough results in the firing of the combustible material and the consequent opening of the latch through the elimination of the coupling force between the structural members.

Abstract: The mounting assembly of the present disclosure finds particular application in shielded electrical cable having connectors at opposite extremities thereof and carrying electrical conductors between spaced-apart equipments having respective mating connectors. In accordance with the disclosure, a mounting assembly is provided which may be disposed at either extremity of the cable, or at both extremities, and which permits the cable connectors to rotate through a prescribed arc about the cable axis. This rotation compensates for the torsional inflexibility of the cable, thereby facilitating the orientation of the mating connectors required for attachment, and electrically linking the equipments.

Abstract: A data storage cell is provided for use when concatenated with similar cells in a wafer-scale integrated circuit as part of a serial memory chain. Data is stored in or retrieved from a shift register. A data switch is operable, dependently upon a selectable match criterion being met between the successive contents of a key word register and selectable sections of the data stored in register, the particular sections so selected being controlled by the contents of a control register. The access control is such that records are selectively stored in, or retrieved from, a particular cell dependent upon the content of the records themselves thus removing the necessity for keeping track of the position of records in the serial memory chain. The switch is selectably operable to provide a copy of the circulating contents of the data storage register as the signal on a data output line of the cell, so providing a means for non-destructive readout from the cell.

Abstract: An encoder/decoder is described which allows data transmission on an A.C. coupled transmission system. The encoder converts a serial data stream comprised of combinations of logical "1"'s and "0"'s in an NRZ format to an output pulse train. The latter is characterized not only by phase reversal for each bit of data, as required for A.C. coupled systems, but by bit durations which are dissimilar for a logic "1" and "0". The encoded data is transmitted and subsequently applied to the decoder which restores the data to an NRZ format, and provides a corresponding series of clock pulses for interpreting the data. The encoder/decoder may be implemented in a simple logic configuration.

Abstract: Disclosed is a selector switch for use in forming an asynchronous network of concurrent processors where the selector switch receives a message from one input port and transmits it to one of two output ports. A path through the network which has been established can be cleared should it become apparent that that particular path has become locked in due to a malfunction of a component in one of the nodes or switches in the network.

Abstract: A four way arbiter switch for a five port module as a node in an asynchronous speed independent network of concurrent processors, each port of the module including an input selector switch and an output selector switch such that each selector switch has a plurality of output channels one for each of the output arbiter switches (except the arbiter switch associated with its own port). Each selector switch is adapted to select a particular output channel (arbiter switch) according to the initial bits received in the asynchronous speed independent message. In this manner, the module of the present invention can accommodate up to five simultaneous asynchronous message transmissions without nodal blocking although the average number of simultaneous messages that can be accommodated will be less.

Abstract: An improved document feeder employs sets of rollers between which it feeds documents of different lengths to generate and maintain gaps of equal length between the documents while transporting them at a constant speed. A first group of rollers separate stacked documents and start the documents moving at a low speed along the track. A second group of rollers, operated at a higher speed, receive documents from the first group of rollers and increase the speed of the first document relative to a second document, still in contact with the first group of rollers, thereby providing an initial gap which continues to lengthen until the second document reaches the second group of rollers. A third group of rollers receives the documents after they leave the second group, imparting a constant system transport speed to them.

Abstract: Non-impact offset printing apparatus providing repeatable top-to-bottom registration of printed matter transferred to cut sheet paper fed in the "portrait" direction by means of a timer-interposer mechanism which contacts the leading edge of each incoming sheet and times the entry of the sheet into the transfer point adjacent to the rim of the offset non-impact rotary printing apparatus effectively creating positive and accurate registration of all four margins of printed matter on each page.