Other

Circom Inc.

William T Bloodworth

John J Bednarz

A telephone controller for connecting a single-line telephone in a local N-line system with other telephones equipped with similar controller comprises N interface units each connecting one telephone line to a dual conductor telephone bus in turn connected to the telephone. Each interface unit includes an off-hook/ring detector connected to the telephone line served by that unit, a hold latch to connect a load of predetermined impedance across the telephone line to simulate an off-hook condition, a hold bus driver connected to a hold bus line extending to all system controllers, a telephone line condition indicator lamp that indicates on-hook, off-hook, incoming ring and hold conditions on the line, a line switch for connecting the telephone line to the telephone bus, an activity monitor to detect an off-hook condition for the telephone bus attributable to the associated telephone line, a telephone condition indicator lamp actuated by the activity monitor, a line selector switch, and line switch control circuits to close the line switch in response to actuation of the line selector switch and to keep it closed in response to detection of an off-hook condition by the activity monitor. The controller also comprises a hold switch, a hold latch control that actuates a hold latch when the hold switch is operated coincident with detection of an off-hook condition by the activity monitor associated with that hold latch, audible signal means to signal an incoming call, and a conference switch enabling conference calls.

Plural line telephone controller

A pulse code modulated digital automatic exchange for a telephone network or other communication network has a multiplicity of N input/output ports connected to an input/output system comprising a plurality of multiplexers that each scan a small group of ports in a predetermined cycle; output signals from the multiplexers are converted into M-bit parallel digital data signals and recorded in an input data store at a location identified with the port of origin. The input data store is scanned, by a fully bused synchronous transfer system, in accordance with a predetermined transfer time cycle having at least N fixed transfer time slots, one for each communication port; during the transfer time slot for any port, data recorded in the input store from that port is transferred, via an M-digit parallel data bus, to a location in an output data store associated with another port for which that data is destined. From the output store the data signals are supplied to a reverse converter and then to de-multiplexers, all part of the input/output system, connected back to the input/output ports. Sequence control circuits control the timing of operations within the transfer system to correlate the transfer of data, during a call between any two ports, so that the transfer time slot for each port in a given call becomes the input time slot for that port and the output time slot for the other port. Hook switch information, tone data, port identification data, and all other control information is bused throughout the transfer system of the exchange. For networks in which data is already in digital form, the conversion stages may be required to translate from serial to parallel form or from one digital format to another, as contrasted with the analog-to-digital conversion required for audio circuits. The input and output stores may be combined in a unified input/output store.

Pulse code modulated digital automatic exchange

A cash replacement system using consumable transaction cards, each card comprising a body portion bearing multi-digit magnetically recorded validation and identification codes and a transaction portion divided into a plurality of transaction segments bearing the identification code and a denomination code, both magnetically recorded. A card reader senses the validation code and severs one transaction segment from the card for each transaction after checking the denomination and assuring presence of the required segment. Printed indicia on each card enable the user to determine the number and denomination of possible remaining transactions.

Growing community of inventors

Naperville, IL, United States of America

William T Bloodworth