JPS6362937B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a dial confirmation tone generation circuit in a subscriber telephone. There are generally two methods for transmitting the contents of a dial operation to a switching center: a pulse dial method and a tone dial method. In the pulse dial system, the number of continuous pulses received at a pulse rate of, for example, 10 times per second is counted as a dial signal. In the tone dial system, a dial signal is a signal that is a combination of two types of sine waves that individually correspond to numbers, symbols, etc. on the dial. By the way, if you use pulse dialing, for example, to call a bank's main phone number, and tone dialing to check your bank account balance,
It is convenient to provide a circuit that generates a dial confirmation sound to confirm the operation of both dials.
In this case, it is more convenient for the confirmation sounds for the operations of both dials to be different than for them to be the same. On the other hand, configuring both dial system circuits with a single chip IC is
This can contribute to reducing circuit manufacturing costs. However, conventionally, sound generation circuits for confirming the operation of both dials have been provided separately. Therefore, even if it is possible to reduce manufacturing costs by configuring the circuits for both dial systems on a single chip IC in the conventional system, it is necessary to add a dial confirmation sound generation circuit for the pulse dial system separately, and the circuit This not only complicates the configuration, but also poses difficulties in reducing manufacturing costs. The present invention incorporates both dial type circuits into one chip.
It is configured with an IC and does not require a separate pulse dial type dial confirmation sound generation circuit.
That is, it is an object of the present invention to make it possible to generate a confirmation sound for operation of a pulse dial using a circuit configuration that is simple and inexpensive to manufacture. Hereinafter, the present invention will be explained in detail based on an embodiment shown in the drawings. FIG. 1 is a circuit diagram of this embodiment. In FIG. 1, numeral 1 is a keyboard in which numerical keys, symbol keys, etc. are arranged in a matrix, and numeral 2 is a one-chip IC including a pulse dialer circuit and a tone dialer circuit. The IC 2 includes a keyboard logic 3 that outputs a predetermined dial signal in response to a dial operation on the keyboard 1, a pulse dialer circuit 4, and a tone dialer circuit 5. The pulse dialer circuit 4 includes a memory 6 for storing the output of the keyboard logic 3, a counter 7 for counting dial signals stored in the memory 6,
It also includes a circuit 8 that outputs a pulse dial based on the output of the counter 7. The tone dialer circuit 5 is connected to the reference oscillation circuit 9 and the row side (row) of the keyboard 1.
and a row counter 10 and a column counter 11 that count the output from the keyboard logic 3 corresponding to each column, and sine wave counters 12 and 13 that count the outputs of both counters 10 and 11, respectively. /A converter 14,1
5 and an amplifier 16. 17 is a crystal oscillation element externally attached to IC2 for reference oscillation, 18 is a mode changeover switch that can be switched according to tone dial mode and pulse dial mode,
The individual contact C ₁ on the tone dial mode side connected to the power supply V _DD , the individual contact C ₂ on the grounded pulse dial mode side, and the movable switch that can be switched by manual operation for both the individual contacts C ₁ and C ₂ . Contact C ₃
Equipped with. This movable contact _C3 is connected to the keyboard logic 3. The keyboard logic 3 is adapted to give a predetermined dial signal to both dial circuits 4, 5 in accordance with the switching position of the movable contact _C3 . 19 is an amplifier that derives an output for generating a dial confirmation sound when in pulse dial mode;
This amplifier 19 sends the output of one of the counters 10, 11 to the corresponding sine wave counters 12, 13,
The signal is received via D/A converters 14 and 15, and the output is provided to an audio output device (not shown). This amplifier 19 is also prohibited from providing output to the audio output device by an output prohibition signal from the keyboard logic 3 when the mode selector switch 18 is switched to the individual contact _C1 on the tone dial mode side. It is becoming more and more common. FIG. 2 is a circuit diagram of the row counter 10 and column counter 11. In FIG. 2, a reference signal S ₁ is applied from a reference oscillation circuit 9 to both counters 10 and 11 via a signal line l ₁ . Signal S ₂ from keyboard logic 3 has 4 signal lines
It is applied to the row counter 10 via a bus _B1 including _l2 , _l3 , _l4 , _l5 and a signal line _l6 . Each input R ₁ , R ₂ , R ₃ , R ₄ of the row counter 10 receives a signal from the keyboard logic 3 corresponding to each key on the row side of the keyboard 1. Another signal S ₃ from the keyboard logic 3 is connected to a bus B ₂ containing four signal lines l ₇ , l ₈ , l ₉ , l ₁₀ and a signal line l ₁₁
It is given to the column counter 11 via. Each input section C ₁ , C ₂ of the column counter 11,
C ₃ and C ₄ are supplied with signals from the keyboard logic 3 corresponding to the respective keys on the column side of the keyboard 1. In addition, 20 is an AND circuit, and when the signal S3 from the keyboard logic ₃ inputted via the signal line _l11 and the output of the tone dial mode match, the output is sent to the column counter 11.
give to Therefore, when the tone dial mode output is not provided to the AND circuit 20, the output from the column counter 11 is no longer provided to the sine wave counter 13. Now, in the tone dial mode, tone dial outputs as shown in the following table are outputted via the amplifier 16.

[Table] In this table, rows 1 to 4 indicate the frequencies f _R1 to f _R4 of each output of the row counter 10, and columns 1 to 4 indicate the frequencies f _C1 to f _C4 of each output of the counter 11. show. Therefore, for example,
When the numerical key "1" on the keyboard 1 is operated, the row counter 10 outputs the frequency f _R1 and the column counter 11 outputs the frequency f _C1 .
These outputs are superimposed at the outputs of the D/A converters 14 and 15 and then output from the amplifier 16. Therefore, an output having a frequency corresponding to each key of the keyboard 1 is derived from the amplifier 16 as a tone dial output. At this time, the D/A converter 1 is also connected to the other amplifier 19.
A combined output of 4 and 15 is given, but since the output operation of this amplifier 19 is prohibited, it does not derive any output. By the way, when in tone dial mode,
Since the tone dial mode output is not given to the AND circuit 20 in FIG.
The output of 1 passes through the sine wave counter 13 and the D/A converter 15 and is not given to the amplifier 19. on the other hand,
The output of row counter 10 is sine wave counter 1
2, applied to the amplifier 19 via the D/A converter 14. Since the prohibition of the output operation of this amplifier 19 has been lifted, only a single frequency output from this amplifier 19, that is, the output from the row counter 10 is used as the output for generating the dial confirmation sound in the pulse dial mode. It is derived as Figure 3 shows row counter 10 and column counter 1.
1, and parts corresponding to those in FIG. 2 are given the same reference numerals. What should be noted in FIG. 3 is that the input section R ₁ of the row counter 10 is provided with an OR circuit 21, and the other input sections R ₂ , R ₃ , and R ₄ are provided with AND circuits 22 , 23 , and 24 , respectively. That's true. In the circuit shown in Figure 2, the row counter 1
0, the outputs of each frequency f _R1 to f _R4 are derived, but in the circuit of FIG. 3, in the pulse dial mode, the output of the column counter 11 is not only inhibited by the AND circuit 20 , the output of the signal S ₂ input to the input sections R ₂ , R ₃ , and R ₄ of the row counter 10 is prohibited. Then, the input section R ₁ of the row counter 10
I am trying to output the output for .
Therefore, in the pulse dial mode, no matter which key on the keyboard 1 is operated, only the output of a single frequency f _R1 will be output from the low counter 10, and the dial confirmation sound from the amplifier 19 will be output. The generation output is a single frequency f _R1 output.
In the above-described embodiment, the output of the row counter 10 is used as the output for generating the dial confirmation sound, but it goes without saying that the output of the column counter 11 can be similarly implemented as the output for generating the dial confirmation sound. As described above, according to the present invention, the tone dialer circuit and the pulse dialer circuit are configured with a single chip IC, and the tone dialer circuit is installed on each of the horizontal and vertical columns of the keyboard in which keys are arranged in a matrix. It has a corresponding row counter and column counter, and in the pulse dial output mode, the output of one of the counters is used as the output for generating the dial confirmation sound, so both dialer circuits can be manufactured by configuring them with a single chip IC. In addition to being able to reduce costs, it is no longer necessary to provide a circuit for generating a dial confirmation sound separately from both dialer circuits, which not only simplifies the circuit configuration but also reduces manufacturing costs. It is played.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, with FIG. 1 being an overall circuit diagram, and FIGS. 2 and 3 showing a row counter 10.
3 is a circuit diagram for applying signals to each input section of the column counter 11 and the column counter 11. FIG. 1...Keyboard, 2...1 chip IC, 3...
...Keyboard logic, 4...Pulse dialer circuit, 5...Tone dialer circuit, 10...Row counter, 11...Column counter, 19...Dial confirmation sound output amplifier.

Claims (1)

[Claims] 1 A tone dialer circuit and a pulse dialer circuit are configured with one chip IC, and the tone dialer circuit is
It has row counters and column counters corresponding to the horizontal and vertical columns of the keyboard, in which keys are arranged in a matrix, and when in pulse dial output mode, the output of one of the two counters is output for generating a dial confirmation sound. Dial confirmation tone generation circuit in subscriber telephones used for.