Abstract: In a telephone system serving premises having a plurality of terminals offering subscriber selectable features, an arrangement is described for changing the active features of the terminals according to whether the associated subscribers are on or off the premises. The arrangement comprises a device for generating signals identifying the subscribers and indicating an "in" or "out" status therefor, a memory for storing data indicating the features required by the respective subscribers in their "in" and "out" status, and a device responsive to the signals and the data stored in the memory to select the appropriate features in the telephone system as the subscribers enter and leave the premises.

Abstract: A method of processing calls in a telephone switching system which is comprised of voice trunks and a message signalling link for carrying signalling data relating to calls on the voice trunks, and a processor for controlling the switching system. The method comprises the steps of receiving an incoming signalling message on the signalling link, converting the message into signalling messages of a type recognizable by the processor as received from a voice trunk, and including a signalling trunk identification address, looking up in a table a correspondence between the signalling trunk identification address and a voice trunk identification address, passing the messages with the voice trunk identification address replacing the signalling trunk identification address to the processor, and processing the call in the switching system as if the messages had come from the voice trunk.

Abstract: A method of providing a visual indication to a first communication connection (CC) subscriber of the status of a telephone CC comprising the steps of providing ah icon on a display that represents the first CC subscriber, providing a call setup icon on a display representing a command to set up a CC, dragging the icon representing the first CC subscriber to the call setup icon, automatically displaying a directory of subscribers, dragging an identity of a second CC subscriber from the directory to the call setup icon, establishing a CC between communication apparatus used by the first subscriber and communication apparatus used by the second CC subscriber via subscriber's lines, changing the identity of the calls setup icon to a call icon, displaying an icon representing the second CC subscriber in the call icon, and displaying a new call setup icon, whereby icons representing CC subscribers of a call in progress are both represented and are visually discernible by the first CC subscriber in the call icon.

Abstract: A method of resource management for elements interfacing a communication control system is comprised of firstly providing a queue list containing a sequence of fields. Each field contains at least the number of a queue in which the element is contained. A table of queue records is provided, each containing at least a head pointer to a first element in the queue list. A record of the table is accessed, and the head pointer stored therein is retrieved. The element number represented by the head pointer is accessed for use by the control system.

Abstract: A method of maintaining directory data in a switching system network having plural switching systems and a centralized directory data management system in which local directory data is stored at each switching system, A copy of directory data of all the switching systems is stored at the management system. Directory data entries of the directory data stored at the management system are associated with groups of switching systems. Data entries associated within each group are downloaded to the switching systems designated in that group.

Abstract: A semiconductor test chip has an array of active semiconductor devices to be individually tested, a number of test lines for connection to external test circuitry, an enabling circuit associated with each device for selectively connecting it to the test lines, an input for receiving an instruction identifying a device that it is desired to test, and a decoder incorporated into the chip for receiving the instruction from the input. The decoder is connected by enabling lines to the individual test devices so that on receipt of an instruction the decoder enables the identified test device such that it becomes connected to the test lines. This circuit is more efficient and less cumbersome than the prior art.

Abstract: An auxiliary regulated power supply is described for use in a system having a main load directly connected to a main regulated power supply and an auxiliary load connected to the main regulated power supply by a line in which a voltage drop occurs. The auxiliary regulated power supply comprises a pair of input terminals for connection to the line, a pair of terminals for connection to a voltage source, a pair of output terminals for connection to the auxiliary load, a circuit for sensing the voltage at the output terminals, and an arrangement for boosting the output voltage at the output terminals from a secondary voltage source as necessary to maintain it at a level appropriate for the auxiliary load.

Abstract: A telephone switching system is comprised of a main controller, switching circuits controlled by the main controller, a peripheral controller for controlling the seizing of subscriber lines for calls routed through the switching circuits, and further comprising a first memory associated with and accessible by the main controller for storing user data associated with each directory number, the user data comprising a ring type, a second memory associated with the peripheral controller for storing ringing cadence indicators associated with respective plural ring types, the main controller for reading the station data from the first memory upon receiving a request for service to a directory number, and sending the ring type indicator with a subscriber line seize message to the peripheral controller, the peripheral controller for reading the second memory and obtaining the ring cadence indicators associated with the ring type, and ringing a line according to the indicated ring cadence.

Abstract: An integrated circuit analog crosspoint switch FET array which utlilizes considerably reduced silicon substrate area than previously. In a preferred embodiment, pairs of the separate diffused regions of different FETs which are connected to the same input are common, forming separate single diffused regions. The separate single diffused regions and the central single diffused regions alternate continuously in a row, separated by the channel regions forming the various transistors. The result is a continuous row of transistors having common diffused regions, except for the transistors at the end of the row, which have their outer diffused regions not in common with any other.

Abstract: A method and apparatus for holding a line busy from which a party has disconnected and providing an indication to the other party that the first party has hung up. The invention operates by receiving a call in a telephone switching office from a first subscriber on an incoming line destined for a second subscriber, storing an indication signal signifying that the call has been received; in case the first subscriber has hung up, accessing the indication signal, and as a result sending a signal to the second subscriber which is indicative that the first subscriber has hung up. Such systems are useful in emergency call handling systems, such as 911 emergency call systems.

Abstract: A handsfree telephone circuit has separate transmit and receive audio paths for connection to a microphone and speaker respectively. The circuit comprises a controllable attenuator in each of said transmit and receive paths, an attenuator control responsive to control signals to set the attenuation level of said attenuators, and a separate monitoring circuit connected to each of said transmit and receive paths for sensing audio signals therein. Each monitoring circuit comprises a filter for band limiting the audio signals, a peak level detector receiving said band limited signals, and a speech detector for distinguishing speech from background noise. A switching comparator compares the outputs of the peak level detectors in the two monitoring circuits and produces directional control signals for said attenuator control means to determine which audio path has control. The circuit eliminates "hollow" effect in the speech due to bandlimiting filtering in the audio paths.

Abstract: In a method of planarizing a semiconductor wafer having aluminum interconnect tracks formed thereon, a method is disclosed for applying inorganic spin-on glass which comprises applying the spin-on glass to the wafer in a coating and spinning chamber in a moisture-free environment, transferring the wafer in a moisture-free environment to a curing station, curing the spin-on glass at a temperature in the range of about 80.degree. to 250.degree. C. in the moisture-free environment at the curing station, and returning the wafers to the coating and spinning chamber. The above steps are repeated until a sufficient film thickness has been achieved without in the interim exposing the wafer to moisture conditions such that reverse hydrolysis si minimized during the planarization process. In this way crack-free inorganic SOG films can be produced.

Abstract: A method of manufacturing a semiconductor wafer, which includes performing a first metallization to deposit a first layer of interconnect material on a substrate, etching the interconnect material to form interconnect tracks, depositing a first low temperature dielectric layer over the interconnect tracks, planarizing the first low temperature dielectric layer with quasi-inorganic or inorganic spin-on glass by a non-etchback process, depositing a second low temperature dielectric layer over the spin-on glass, etching via holes through the dielectric and spin-on glass layers to reach the tracks of the first interconnect layer, performing an in-situ desorption of physically and chemically bonded water vapour in a dry environment at a temperature of at least 400.degree. C. and not more than 550.degree. C. for a time sufficient to obtain a negligible desorption rate, the temperature exceeding by at least 25.degree. C.

Abstract: A method of establishing a telephone communication link from a calling line to one of plural peripheral devices associated with a single telephone number in a central office telephone switching system or PBX is comprised of storing in a memory a first table of directory numbers and equipment identifiers associated with each directory number, storing in a memory a second table of references to physical peripheral devices associated with each equipment identifier, receiving a request for service to a particular directory number, accessing the first table using the particular directory number and obtaining references to all equipment identifiers associated therewith, accessing the second table using the particular equipment identifiers associated with the particular directory number and identifying the particular physical peripheral devices associated with the particular identifiers, ringing all of the particular physical peripheral devices, detecting one of the particular physical devices going off-hook, ceasin

Abstract: A method of fabricating multilevel semiconductor wafers including a spin-on glass planarization layer is described. Prior to sputtering of the interconnect layer and after application of the spin-on glass layer, the wafer is exposed to an intense glow discharge in such a way that it is bombarded in at least a partial vacuum with ions and/or electrons and/or photons while at a temperature that is between 400.degree. C. and 550.degree. C. and that is at least 25.degree. C. higher than the temperature to which the wafer is to be subjected during the subsequent sputtering step. In this way undesirable molecules can be desorbed from the spin-on glass layer so that they do not interfere with the subsequent sputtering step.

Abstract: A telephone apparatus comprises a base and a handset. An inclined cradle is provided on the base for receiving the handset and is shaped such that a handset placed thereon normally falls naturally into a fully seated position. A switch responsive to the presence or absence of the handset in the cradle places the apparatus in an "on-hook" or "off-hook" condition respectively. A co-operating arrangement respectively on the handset and the base permit the handset to be temporarily retained in a partially seated position on the cradle without activating the switch so as to permit the handset to be parked temporarily on the cradle without placing the apparatus in the "on-hook" condition.

Abstract: A receiver including a vibrator plate vibrating together with a voice coil in response to electrification of said voice coil which comprises an electrostatic discharge prevention plate having a central opening arranged above the vibrator plate with a small air gap provided therebetween. A metal cover around the top and sides of the receiver is imbedded in plastic for inhibiting electrostatic discharge via the cover. As a result the discharge path length through the air is substantially increased, reducing the likelihood of electrostatic discharge from the ear of the user.

Abstract: In accordance with an embodiment of the invention, a method of establishing call progress tones for a switching system having a generic signal generating apparatus, comprising the steps of displaying at least one form on a display and inserting into fields of the form definitions of the cadencing and particular generic signals associated with each call progress tone for a tone plan, temporarily storing the definitions in a memory, compiling the definitions as control signals into object code, storing the object code in a random access memory, and using the object code in the processing of a call by a switching system processor to control provision of particular signals from the generic signal generating apparatus with a particular cadence and signal level to a subscriber or operator.

Abstract: A digital switching system comprises a plurality of digital interface cards for connection to a public telecommunications network, each card including at least one digital interface circuit with a synchronization detector for detecting a network synchronization signal. A control unit includes a system clock having a clock synchronization input. A a system bus carries data through the switching system and is connected between the interface cards and the control unit. A switch in the interface cards is operative in response to control data from the control unit and carried over the system bus in an overhead channel to connect the synchronization detector of a selected active digital interface circuit to the clock synchronization input of the system clock over a clock synchronization line so as to pass detected synchronization signals on the active circuit directly thereto. The system clock can thus be brought directly into synchronization with the detected synchronization signal of the active interface unit.