AU749917B2

AU749917B2 - Voice mail detector arrangement for a telephone

Info

Publication number: AU749917B2
Application number: AU23700/99A
Authority: AU
Inventors: Spiro Petratos
Original assignee: Alcatel SA; Nokia Inc
Current assignee: Alcatel Lucent SAS
Priority date: 1998-04-14
Filing date: 1999-04-12
Publication date: 2002-07-04
Anticipated expiration: 2019-04-12
Also published as: AU2370099A

Description

r1W P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "VOICE MAIL DETECTOR ARRANGEMENT FOR A TELEPHONE" The following statement is a full description of this invention, including the best method of performing it known to us: This invention relates to telephone subsets, and in particular to telephone subsets for connexion to a telephone system that includes an exchange-based message recording systems, sometimes called "message bank" or "voice mail", wherein the presence of a message can be determined by a subscriber by bringing a phone connected to such a system into the off-hook mode. If one or more messages have been left in the message bank, a stuttering dial tone, transmitted from exchange equipment, will be heard in the phone's receiver. A problem exists in that, in addition to the audible indication of a left message, a visual indication is desirable.

A known arrangement for providing a visual indicator comprises means to periodically and automatically cause the phone to seize the exchange line for a minimum period while the phone is in the on-hook mode. If stuttering dial tone is present upon automatic seizure, a display means and a message light means are activated.

S 15 Such a solution however, is unsatisfactory in that it is not uncommon to have •a number of parallel phones connected to one exchange line. Periodic seizures by each of the parallel phones for purposes other than establishing a connexion with another subscriber is unacceptable to Telecom Authorities because such multiple seizures overload register equipment and the like at the exchange, and do not generate revenue.

It is an object of the present invention to provide an arrangement by which only a selected one of a plurality of parallel phones connected to an exchange line is able to seize the exchange equipment while in the on-hook mode for the purpose of detecting the presence of stuttering dial tone.

According to the invention, in a telephone system that includes an exchangebased message recording system in which the presence of a message for a subscriber whose telephone is connected, via an exchange line, to such an exchange can be determined by the presence of a message tone on said exchange line when the subscriber causes said telephone subset to loop exchange equipment, a parallel telephone arrangement for connexion to such a telephone system, said arrangement comprising a plurality of telephones comprising one selected master telephone and remaining slave telephones, all connected in parallel to a common exchange line, each said telephone including a programmable microprocessor, an electronic line switch, a message-tone detector, a parallel phone detector, a display means and means to select a master telephone, wherein each telephone's associated programmable microprocessor is programmed to perform, when all telephones are in an on-hook mode, a controlled periodic line seizure cycle that produces a periodic line seizure enabling pulse only in the programmable microprocessor associated with the selected master telephone, whereby only said master telephone's associated electronic line switch is enabled to periodically loop the exchange line for a predetermined period thereby periodically coupling said master telephone's associated message-tone detector to said exchange line, and if message-tone is detected during said predetermined period, said master telephone's associated microprocessor enables the master telephone's display means, and wherein upon each slave telephone's associated parallel phone detector detecting 15 that said master telephone's associated electronic line switch has been enabled by a line seizure enabling pulse in the master telephone's programmable microprocessor, the line seizure enabling pulse in each of said slave telephone's programmable microprocessors is disabled.

In order that the invention may be readily carried into effect, an embodiment thereof will now be described in relation to the figure of the accompanying drawing, which shows a block schematic of one of a plurality of parallel phones connected to a exchange having an exchange-based message bank facility. All of the parallel phones are the same as that shown in the figure.

Referring to the figure of the drawing, the telephone comprises a programmable microprocessor 1, an electronic line switch 2, a stuttering dial tone detector 3, a parallel phone detector 4, a display means 5, an LED 6, a keypad 7, and a master selector means (not shown), to select a master telephone. Preferably, the master selector means is a dedicated key on the telephone. In the parallel arrangement of telephones according to the present invention the telephone selected by the user to periodically seize the line in the on-hook mode to detect a left message in the exchange based message bank, and provide a visual indication on that telephone when a left message is detected, is referred to as the master telephone. The remaining parallel telephones are referred to as slave telephones which, when in the on-hook mode, are unable to periodically seize the line when in on-hook mode.

This selective seizure of the line in the on-hook mode is accomplished by a program in each programmable microprocessors 1 programmed to perform a controlled periodic line seizure cycle of a predetermined period, typically every minutes. In each said line seizure cycle there is produced a line- seizure enabling pulse, typically of 15 seconds duration, which is utilised in the selected master telephone to enable its electronic line switch to seize the line for the duration of the pulse, but this pulse is prevented from occurring in each slave telephone by a control signal provided by each slave telephone's parallel phone detector which detects the off- hook operation of the master telephone's electronic line switch by sensing a change in line voltage or line current caused by the master telephone being in an off-hook condition.

Preferably, the programmable microprocessors 1 are programmed such that, 0 on initial installation of the parallel telephone arrangement, the first telephone to be brought into an off-hook mode becomes the master telephone, the remaining telephones becoming slave telephones. Henceforth, this selected telephone remains the master telephone until the master selector means is operated on a slave .i telephone chosen by the user to be the new master telephone; the old master telephone becoming a slave telephone after a "handshake" with the new master telephone at the line seizure enabling pulse of the next line seizure cycle.

The controlled periodic line seizure cycle is programmed to stop when any telephone in the parallel arrangement is brought into the off-hook mode by a user to either establish a call or to answer an incoming call; the said cycle starting again when the off-hook telephone goes on-hook.

Claims

1. In a telephone system that includes an exchange-based message recording system in which the presence of a message for a subscriber whose telephone is connected, via an exchange line, to such an exchange can be determined by the presence of a message tone on said exchange line when the subscriber causes said telephone subset to loop exchange equipment, a parallel telephone arrangement for connexion to such a telephone system, said arrangement comprising a plurality of telephones comprising one selected master telephone and remaining slave telephones, all connected in parallel to a common exchange line, each said telephone including a programmable microprocessor, an electronic line switch, a message-tone detector, a parallel phone detector a display means, and means to select a master telephone, wherein each telephone's associated programmable *see microprocessor is programmed to perform, when all telephones are in an on-hook mode, a controlled periodic line seizure cycle that produces a periodic line seizure S 15 enabling pulse only in the programmable microprocessor associated with the selected master telephone, whereby only said master telephone's associated electronic line switch is enabled to periodically loop the exchange line for a predetermined period thereby periodically coupling said master telephone's associated message-tone detector to said exchange line, and if message-tone is 0 0 detected during said predetermined period, said master telephone's associated :microprocessor enables the master telephone's display means, and wherein upon G each slave telephone's associated parallel phone detector detecting that said master telephone's associated electronic line switch has been enabled by a line seizure enabling pulse in the master telephone's programmable microprocessor, the line seizure enabling pulse in each of said slave telephone's programmable microprocessors is disabled.

2. A parallel telephone arrangement substantially as herein described with reference to the figure of the accompanying drawings. DATEDTHIS THIRTYFIRST DAYOF MARCH 1999 RA~\" ALGATE! R E

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