GB2183423A - Telephone tone caller - Google Patents

Abstract

A tone calling arrangement, for a telephone set, includes a microprocessor which drives the tone caller. It does this by switching the microprocessor output port between high and low at a rate appropriate to the desired frequency. This switching is also done in a pattern to give the wanted "ringing" pattern. The arrangement is programmed to give the wanted "ringing" signal from the keypad. The microprocessor also performs other functions as needed for a "features" telephone. <IMAGE>

Description

SPECIFICATION Telephone tone caller This invention relatesto tone calling arrangements such as are used in telephone subscribers' apparatus.

Conventional tone callers produce a warbling tone by switching between two or more frequencies at a constant rate. Normallythesefrequencyvaluesare fixed, so that only one tone is allowed. In microprocessor-based telephones it is possible to syn thesisethewaveform using its software. However the user can normally only select one of a small fixed number of combinations.

An object ofthis invention is to enable a telephone userto programme a tone callerto his/her own needs, which is useful in an office with a number of telephones.

According to the invention there is provided a tone calling arrangementfor use in a telephone sub- scriber's instrumentorthe like, which includes tone calling circuitry connected to and controlled via an output from a microprocessor, wherein the microprocessor controls the tone caller by alternately switching said output between high and low con- ditions at a rate appropriate to the desired tonefrequency, wherein the switching is so effected that the tone has a desired pattern of on and off states, and wherein the parameters which effect said control of the tone output are programmed into the microprocessor from the instruments keypad or the like, whereby the instrument's ringing tone can be given the frequency and on-off characteristics desired by the subscriber.

An embodiment of the invention will now be des cribed with reference to the accompanying highly schematic drawing.

A microprocessor as used in the present arrange ment can be programmed to produce a number of different frequencies, e.g. it can produce sixteen dif ferent values forthe switching frequencies, and up to sixteen values for the warbling frequency. This would, in the case of a dual-tone ringer, permitthe production of 2176 differenttones. Similartech- niques to those described herein can be used in a three tone ringer.

The central element of the arrangement to be des cribed herein, seethe drawing, is a microprocessor which controls the tone generation. It also performs otherfunctions as needed bythefacilities provided by the telephone instrument in which it is used.

Thus, as can be seen, the microprocessor monitors all the user inputs and outputs, which include a keypad, handset (i.e. off hook-on hook indications) and a recall button to the tone caller. There are also outputs to lineforVF, marked DTMF (Dual-Tone Multi-Frequency), and for DC pulsing. It also controls thetone caller, as will be described.

When a ringing tone is needed, the micro processor creates a drive waveform on the output to the tone caller circuitry, this latter includes one or more amplifiers, with volume control, and an output transducer. The output waveform is produced by switching the output port between its high and low levels at a rate appropriate to the frequency used for the tone ringer.

When the user programmesthetonecaller, he enters a value from the keypad, which value is stored in the microprocessor's internal memory. During ring ing the microprocessor usesthis value to varythe period of the drive waveform, i.e. its frequency. Also entered at this stage are other parameters to control the on-off patterns of the tone. The values thus entered are entered after a special "tone caller programme" prefix is keyed in. This prefix is followed by one or more values to define the nature ofthe ringing signal required.

1. Atone calling arrangementforuse in atelephone subscriber's instrument or the like, which includes tone calling circuitry connected to and controlled via an output from a microprocessor, wherein the microprocessor controls the tone caller by alternately switching said output between high and low conditions at a rate appropriate to the desired tone frequency, wherein the switching is so effected that the tone has a desired pattern of on and off states, and wherein the parameters which effect said control of the tone output are programmed intothemic- roprocessorfrom the instruments keypad or the like, whereby the instrument's ringing tone can be given the frequency and on-off characteristics desired by the subscriber.

2. An arrangement as claimed in claim 1 ,wherein the tone calling circuitry can produce two-tone or other plural tone outputs, with a large number (e.g.

morethan 2000)tone combinations available, and with a substantial range of patterns available.

3. Atone calling arrangement for use in atelephone subscriber's instrument, substantially as described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Telephone tone caller This invention relatesto tone calling arrangements such as are used in telephone subscribers' apparatus. Conventional tone callers produce a warbling tone by switching between two or more frequencies at a constant rate. Normallythesefrequencyvaluesare fixed, so that only one tone is allowed. In microprocessor-based telephones it is possible to syn thesisethewaveform using its software. However the user can normally only select one of a small fixed number of combinations. An object ofthis invention is to enable a telephone userto programme a tone callerto his/her own needs, which is useful in an office with a number of telephones. According to the invention there is provided a tone calling arrangementfor use in a telephone sub- scriber's instrumentorthe like, which includes tone calling circuitry connected to and controlled via an output from a microprocessor, wherein the microprocessor controls the tone caller by alternately switching said output between high and low con- ditions at a rate appropriate to the desired tonefrequency, wherein the switching is so effected that the tone has a desired pattern of on and off states, and wherein the parameters which effect said control of the tone output are programmed into the microprocessor from the instruments keypad or the like, whereby the instrument's ringing tone can be given the frequency and on-off characteristics desired by the subscriber. An embodiment of the invention will now be des cribed with reference to the accompanying highly schematic drawing. A microprocessor as used in the present arrange ment can be programmed to produce a number of different frequencies, e.g. it can produce sixteen dif ferent values forthe switching frequencies, and up to sixteen values for the warbling frequency. This would, in the case of a dual-tone ringer, permitthe production of 2176 differenttones. Similartech- niques to those described herein can be used in a three tone ringer. The central element of the arrangement to be des cribed herein, seethe drawing, is a microprocessor which controls the tone generation. It also performs otherfunctions as needed bythefacilities provided by the telephone instrument in which it is used. Thus, as can be seen, the microprocessor monitors all the user inputs and outputs, which include a keypad, handset (i.e. off hook-on hook indications) and a recall button to the tone caller. There are also outputs to lineforVF, marked DTMF (Dual-Tone Multi-Frequency), and for DC pulsing. It also controls thetone caller, as will be described. When a ringing tone is needed, the micro processor creates a drive waveform on the output to the tone caller circuitry, this latter includes one or more amplifiers, with volume control, and an output transducer. The output waveform is produced by switching the output port between its high and low levels at a rate appropriate to the frequency used for the tone ringer. When the user programmesthetonecaller, he enters a value from the keypad, which value is stored in the microprocessor's internal memory. During ring ing the microprocessor usesthis value to varythe period of the drive waveform, i.e. its frequency. Also entered at this stage are other parameters to control the on-off patterns of the tone. The values thus entered are entered after a special "tone caller programme" prefix is keyed in. This prefix is followed by one or more values to define the nature ofthe ringing signal required. CLAIMS

1. Atone calling arrangementforuse in atelephone subscriber's instrument or the like, which includes tone calling circuitry connected to and controlled via an output from a microprocessor, wherein the microprocessor controls the tone caller by alternately switching said output between high and low conditions at a rate appropriate to the desired tone frequency, wherein the switching is so effected that the tone has a desired pattern of on and off states, and wherein the parameters which effect said control of the tone output are programmed intothemic- roprocessorfrom the instruments keypad or the like, whereby the instrument's ringing tone can be given the frequency and on-off characteristics desired by the subscriber.

2. An arrangement as claimed in claim 1 ,wherein the tone calling circuitry can produce two-tone or other plural tone outputs, with a large number (e.g.

morethan 2000)tone combinations available, and with a substantial range of patterns available.

3. Atone calling arrangement for use in atelephone subscriber's instrument, substantially as described with reference to the accompanying drawing.