Abstract: A security system arrangement utilizing a standard PBX for monitoring a plurality of concurrently administrable guard tours. A control processor of the PBX administers the security monitoring processing operation. This processing operation monitors the activities of tour guards as the guards progress through one or more tours. In particular, a programmable memory defines a plurality of tours. Each tour comprises a finite list of sequentially defined checkpoints where each checkpoint is a designated conventional station set of the PBX. A security controller activates the security system by "dialing" the appropriate feature code at a central control facility, such as an attendant console. The security controller than selects one or more the available tours by "dialing" a tour code. Following the selection and activation of a tour, a tour guard "dials" a check-in code at each checkpoint and progresses sequentially through the checkpoints contained in the list comprising the selected tour or tours.

Abstract: A multi-stage time division switch interconnects a plurality of processors that individually communicate over one or more channels at various signalling rates. Any processor may initiate a call and request that a connection be set by the switch. The switch assigns one or more time slots to the call and gathers or distributes data over the interconnecting channels through the utilization of polling techniques, thereby creating a virtual circuit through the combination of a time division switch and a polled communication line.

Abstract: There is disclosed a clock circuit for a PBX system that uses phase locked loop technology to perform synchronization between two input signals. The system can switch between different reference sources without introducing error and without requiring the entire circuit to become realigned with the phase of the newly selected reference signal. This is accomplished with a phase build-out circuit that uses a phase locked loop divider to change the phase of the internal control signal to match the phase of the newly selected reference thereby eliminating timing changes on the system clock bus. The system can also be used to change between redundant clock circuits.

Abstract: A communication system includes station sets having one or more function enable buttons and a plurality of line access buttons. The function enable buttons include the extension, transfer and send message buttons. Each line select button is associated with a communication line and with the station set associated with that line. Operation of a function enable button initiates the feature associated with that button and also changes the function of a line select button from a line access button to an auto-dial select button for dialing the station associated with the line select button.

Abstract: A tape, with holes therein adjacent an edge of the tape, an adhesive surface and a succession of discs on such surface, is moved step by step to advance each disc in turn to a work station having pins outward of that edge. At the station, wire is wound around the disc and the pins to form (a) a wire coil surrounding the disc and adhered to such surface, and (b) wire segments extending from such disc to such pins so that each segment spans one of such holes. The segments are pressed against the surface so that each is adhered thereto on opposite sides of the hole spanned by that segment. The segments are severed at such edge to detach them from the pins, and a piece of the tape bearing the coil and adhered severed segments is severed from the rest of the tape and removed from the station. The assemblage comprising such tape piece and the coil and segments thereon constitutes a useful article of manufacture.

Abstract: A data structure and program routines for use in a private branch exchange telephone system (PBX) for automatically routing calls via a private telephone network in response to a dialed public telephone network number and for restricting outgoing calls from the PBX to specific public network telephone stations. In a large corporate PBX switching network interconnected by both a public telephone network and a private telephone network, a telephone set connected to one PBX system establishes a switch connection through the private network by dialing the public telephone network's number for a destination telephone set connected to another PBX system. In response to the dialed number, the first PBX system automatically determines that the destination telephone set can be reached via the private telephone network and automatically converts the dialed public telephone network number to a private telephone network number designating the destination telephone set.

Abstract: Presently available printed wiring board backplanes used in switching systems and the like are wired at the time of manufacture to enable only a fixed number of groups of circuit boards to communicate with each other. This limitation prevents a backplane from having the capability of serving a varying number of groups of boards. The present invention enables a backplane to have the capability of serving a variable number of groups of boards. The number of groups that can be served by a given backplane need not be fixed when the backplane is designed and manufactured. Each backplane of the present invention comprises backplane bus conductors and board conductors. The boards are effectively a part of the bus. The use of a first type of board in a backplane connector continues the bus to the adjacent connector. The use of a second type of board terminates the bus and does not extend it beyond the connector into which the second type of board is inserted.

Abstract: A receiver circuit uses switched capacitor circuits to couple signals received over a communication facility to connected apparatus. During a first time interval a capacitor is connected across each lead of a facility to sample the facility voltages. During a second time interval these capacitors are disconnected from the facility lines and reconnected in series as the input to a voltage regenerator circuit. The regenerator circuit reconstructs the received signals for output to connected apparatus.

Abstract: Circular paths in a multinode connection are avoided by passing an adaptive routing state, from node to node, which specifies the path options that the current node may use in its selection of a next step in the connection. The routing state, which is characterized by, for example, a single digit, is updated by the current node and is a function of the recent path history of the connection. The single-digit routing state controls the advancement of the connection by specifying whether the next selected step can be either a forward step, a null step or a backward step, or any combination thereof. A forward step advances the connection toward its destination, a null step does not advance the connection and a backward step causes the connection to step backward to a node not yet in the connected path. When a node selects a next step, it adapts the routing state digit to reflect its selection and passes the new routing state digit to the next node.

Abstract: A packet switching system having separate arbitration and data buses together with circuitry for dividing the buses into a plurality of time segments termed phases. The plurality of phases permit a like plurality of separate arbitration operations and a like plurality of separate data exchanges to be effected concurrently on the arbitration bus and data bus, respectively. The use of n phases increases the data transmission capability of the system by a factor of n over prior art arrangements using only a single phase.

Abstract: A jack has therein a longitudinal guideway in the back of which the free end of a printed wiring jack board projects longitudinally forward in the guideway and has laterally spaced conductive terminals on its top. The guideway is adapted to slidably receive a cartridge connector plug comprising a cartridge housing with a front opening for a longitudinal passage therein, a pair of axleless resiliently deformable lateral rollers in said housing back of said opening on opposite sides of said passage, and a flex bond unit longitudinally displaceably received in the passage and comprising a printed circuit plug board and a flexible sheet bonded to that board and having a forwardly projecting tail with laterally spaced conductive terminals matching those of the jack board.

Abstract: An arrangement for achieving multi-processing is disclosed for use in a communication system where it is desired to have several independent processors operating in parallel on stimuli received from the connected terminals. Each such terminal is associated with a particular processor and that processor serves to control connections involving its associated stations. Stimuli from the station are stored in a queue and processed in an intermixed fashion such that stimuli from the connection are processed in order of arrival of the stimulus, but stimuli from different connections are processed without regard to the relative order of arrival of stimuli between connections.