SPECIFICATIONRepertory diallerThis invention relates to repertory diallers, such as used with a telephone subscriber's instrument.
The majority of such diallers consist of a unit additional to the telephone instrument, which has some selection arrangement for causing the read out and transmission of wanted numbers. In some cases this consists of an array of switches or push-buttons one per number, while in others the selection is by the insertion into the machine of a perforated card the hole patterns of which represent the number. Such devices are complex and expensive, and in the case of the latter sort, the so-called card dialler, there is the disadvantage that the cards may get lost.
An object of the present invention is to provide an arrangement which minimizes or even overcomes the above disadvantages.
According to the present invention there is provided a repertory dialler which includes digit sending means similar to that normally used for transmitting decimal digits from a telephone subscriber's instrument in response to direct manual digit sending, the elements of said set being allocated alphabetical significations in addition to or instead of the numerical significations, a memory containing the telephone numbers appropriate to a number of different call destinations each of which numbers is located at a memory address defined by two or more of said alphabetical significations, a memory-accessing circuit responsive to the operations of said elements to extract from the memory the telephone number to which the operated elements correspond, and meansfortransmitting a telephone number thus extracted from the memory in a manner appropriate to the telephone exchange to which the repertory dialler is connected.
The digit sending means could in certain instance be a conventional telephone dial, but in our preferred arrangements it is a pushbutton set.
According to the present invention we also provide a repertory dialler which includes a set of push-buttons similar to or including the set of push-buttons normally used for transmitting decimal digits in response to direct manual pushbutton sending the keys of said set each being allocated an alphabetical significance in addition to the numerical sequence, a control push-button or other form of switch which when operated sets the dialler to a repertory dialling condition a memory containing the telephone numbers appropriate to a number of different call destinations each of which numbers is located at a memory address defined by the alphabetical significances of two or more of said push-buttons, a a memory accessing circuit responsive to the operation of said control push-button or other form of switch plus the operation of two or more of said push-buttons to extract from the memory the telephone number to which the operated pushbuttons correspond, and means for transmitting atelephone number thus extracted from thememory in a manner appropriate to the telephoneexchange to which the repertory dialler isconnected.
Such arrangements exploit the fact that mostpeople tend to remember names rather thannumbers. Hence when it is desired to set up a call to a subscriber whose number is in the repertory dialler's memory it is desirable that the caller should be able to enter a name or part of a name in alphabetical form. In this context "name or part of a name" should be considered to include initials or nick-names. The "mechanical" task of relating the name to a complete telephone number is handled by a logic unit.
Consequent upon modern developments in electronics, the logic circuitry needed to do the above task is relatively small and can be readily accommodated in a conventional telephone instrument in addition to the apparatus already present. Such circuitry can be line powered, powered by a battery maintained charged from the line, or locally powered if this is preferable.
The repertory dialler can, if desired, be provided with a small alpha-numeric display of about 1 5 characters to display the called party's name when the dialler is used.
Embodiments of the invention will now be described with reference to the drawings, in whichFig. 1 is an example of a keyboard for a repertory dialler embodying the invention, in which the keys are operated singly or in pairs.
Fig. 2 shows another keyboard suitable for use in a repertory dialler embodying the invention, this being referred to as an "alpha and calculator" keyboard.
Fig. 3 is another keyboard in which the keys are operated singly for number selection.
Fig. 4 is a simplified block diagram of a repertory dialler embodying the invention and using the keyset of Fig. 3.
With suitable logic it is possible to arrange a numerical keyboard to give alphabetical entry with "chord-keying" of two keys at à time, and one possible arrangement is shown in Fig. 1. In this arrangement if key A is operated, the letter entered is A, while if A + C are operated together, then the logic interprets it as B. Other "chordtype" arrangements are possible, including ones based on diagonal associations of keys. Where the keyboard also acts as a digit sender for normal digital number sending, a separate control is needed to set the dialler into its "alpha-controlled" state.
While such a keyset is cumbersome for typing, in the present case where a small number of key strokes, on average two or three being adequate, are made it is acceptable. For best discriminations of names in the dialler's memory, one method is to enter initials of the subscribers to be called in sequence, with as many letters entered as needed to uniquely identify the portion. In each case the initials are followed by the wanted number. Where the instrument has a digital display, the "operation.
of the buttons to select the wanted number also displays the wanted subscriber's name. Thus where the caller keys in WPW, the name W. P.
WILBY appears on the display. This, in addition to having "customer appeal" is a useful check that the correct number has been selected.
Other methods of selection than initials could be used, e.g. forenames or nick-names, and different ways to access a wanted number could be provided if desired.
To simplify the keying, it would be possible to use a larger matrix of keys, e.g. as shown in Fig.2, where the ten keys within the broken line rectangle are the normal keyset of a push button telephone. Although this and other arrangements described herein uses double labelling of keys for both alphabetical and numerical use, such plural labelling is well-accepted on calculators. In fact, the layout of Fig. 2 would also control a calculator in addition to the repertory dialler. This would need a three-way controí switch, for normal numerical push-button "dialling", for repertory dialling, and for calculator use.In the latter case the calculator can be provided with "hold" storage so that if calculator operation has to be interrupted for telephone use, the current state of a calculation can be put in storage until the call ends.
Where the controlling logic includes amicroprocessor, as in the repertory dialler described in our Application No.45604/74 SerialNo. 1 524028 (B. A. Bidwell et al 5-1-1-1), extra functions can be added, e.g. keep trying a number at intervals (often called Camp-on-Busy), select two or more names to be accessed as soon as possible and in sequence with each successful call indicated on the display. Memory capacity should not cause difficulty; thus with 256 bits perperson stored a 1 6K bit memory on a chip isadequate for 40 entries.
The logic for responding to the chord-typekeying uses relatively simple gating controlled in response to operation of two keys at once, andhence is not shown.
In certain cases the use of chord-type keyingmay not be possible especially where the keysetalso has a numerical function since many telephone administrations insist that it not bepossible to operate two keys of the actual digitsending act simultaneously. In such a case thekeys of a conventional keyset are additionallylabelled, e.g. as in Fig. 3, so that each keycorresponds to two or three letters (except the 0key which corresponds to the letter 0) when in thealphabetical function. This is, of course, analogous to the old British system where the digits on the dial had letters as well as numbers. With such akeyset, a 16K bit memory allows the storage ofabout 200 name codes with associated numbers.
In such case three or more key operations may beneeded for some at least of the wanted number selections.
Switching between alphabetical and numerical functions in the arrangement of Fig. 3 uses anadditional switch (not shown), preferably with anindicator light to "teli" the user when the device isin its alphabetic state. A further visual indication,e.g. by flashing the indicator light or an additionalindicator can be given when auto-diallingcommences.
To record a new number, the record made is selected by a separate function key, and flagged by an indicator light. In this case the access code,e.g. the wanted party's initials, followed by hisnumber, is keyed in. The logic circuitry responds tothis by placing the number in a free memory section, which latter is then allotted the accesscode as its address. If al: sections of the memoryare full, a visual indication to this effect is given,e.g. by flashing the record indication light. The user then has to consider erasing one of the less used numbers, for which see below.
If an error is made in wanted number selection, an erase mode is selected by the operation of a separate erase function key, which cancels the existing call. To erase entry from the memory, the user selects erase and then keys the alphabetical code for the memory section to be erased.
During the second mode it may happen that a user inadvertently inserts the same number with its access code for a second time: To advise him of this mistake, the logic can be arranged to compare each entry with all those already in memory, and an alarm given if a duplication has occured. This appears instantaneous to the user as it takes place at "electronic" speeds.
We now consider the highly schematic block diagram, Fig. 4. This is highly schematic as the various individual circuit functions may follow established practice. Further, where a microprocessor is used, the techniques of our above mentioned Application No. 45604/74 Serial No. 1524028 (B. A. Bidwell et al 5-1-1-1) may be used. This particularly applies to the auto-dialler chip.
In this diagram we see the push button instrument 1 which is connected to a line interface 2 and a logic unit 3. This latter may incorporate a microprocessor, and associated with it is a memory chip 4, from which wanted numbers are extracted. Each such number on extraction is passed to an auto-dialler chip 5, which is also connected to the interface 2.
The additional indicator lights R, A and C are for the record, alphabetical operation and conflict function mentioned above, and are controlled from the logic unit 3 via lamp drivers 6. Below the lights are shown the Record, Alpha and Erase function keys.
The blocks 2 to 6 are all, in the preferred arrangement, within the telephone set body, and the keys and lights are on the outside thereof.
Hence we have a powerful and versatile repertory dialler which is no bigger than a convertional telephone set.