KR0150740B1 - Long distance call controller - Google Patents

Abstract

The present invention relates to a long-distance automatic telephone outgoing control device that can block 700 phone calls and mobile phone calls and other area codes other than local area codes, but can make emergency calls or wireless calls in any state. In the long distance automatic telephone call control device according to the present invention, the rectifier outputs a pulse voltage by full-wave rectifying AC voltage, and the line output unit and the voltage output from the line control unit for controlling the flow of current according to the applied signal level to a predetermined level. A line interface section comprising a constant voltage holding section for holding, a data converter for extracting a frequency component from the pulse voltage output from the rectifier section, and decoding the frequency component, and for synchronizing the operation with the signal frequency supplied from the telephone station. The clock generator that generates the clock signal, Extracting the local area code corresponding to the base area code output from the area code memory unit and the area code memory unit storing the base area code, and comparing each extracted near area code with the data signal input from the data conversion unit A central processing unit for controlling the line interface unit by outputting a signal of a high or low level in accordance with whether or not matching, and switch means for controlling the supply of operating power for operating the central processing unit.

Description

Long distance automatic telephone call control

1 is a connection system between a telephone line and a trunk line of a long distance automatic telephone call control device according to the present invention.

2 is a detailed circuit diagram of a long distance automatic telephone call control device according to the present invention.

* Explanation of symbols for main parts of the drawings

1: line interface unit 2: data conversion unit

3: Clock generator 4: Area code memory

5: central processing unit 6: switch unit

D1, D2: Rectifier IC1: Photocoupler

IC2: DTMF Decoder IC3: EEPROM

IC4: One-chip microprocessor ZD1, ZD2: Zener diode

[Field of Invention]

The present invention relates to a long-distance automatic telephone call control device, and more particularly, the 700 service, as well as the wireless telephone (mobile phone) call and other area code calls other than the local area code, but emergency calls or radio calls in any state (Beep) relates to long distance automatic telephone call control system.

[Prior art]

In offices and hospitality offices, unauthorized people can make some high-priced tolls such as long-distance calls, international calls, mobile phone calls, and 700 country calls, which can cause damage to subscribers. have. It is impossible for the subscriber to leave this situation as it is, but it must be very cumbersome to monitor it individually. In addition, it may be considered that in places such as hospitality, free calls such as radio calls or emergency calls as well as to the area where the city rate is applied are allowed to unauthorized persons.

Therefore, at the request of the subscriber, long-distance tolls such as the above-mentioned long distance calls can be blocked, while low-cost or toll-free calls such as radio calls or emergency calls to the city rate coverage area can be permitted. Automatic telephone call control device has been developed.

However, in the long-distance automatic dialing control system developed to date, all long-distance area codes to be blocked had to be entered by pressing the telephone button. This would be very cumbersome considering that there are about 140 area codes in Korea. Also, if the phone subscriber moves to the base area where the phone is registered, the area code to be blocked must be entered again. Will be added. In addition, long-distance automatic call outgoing control method requires a password to be entered, so if a password is leaked, the long-range automatic outgoing call control will not be effective and the subscriber must always remember the password. There is no guarantee of reliability to the subscriber.

[Overview of invention]

The present invention has been made to solve the above inconvenience, by adopting a switching method using a key instead of a password input method for long-distance automatic telephone call control to improve security, and input the area code to block Even if you enter only the area code of the base area where you subscribed to the phone, you can automatically block the long distance area code outside the local area where the local call charge is applied, and do not block the wireless call or emergency call, and only receive the call. It is an object of the present invention to provide a long distance automatic telephone call control device that can enable it.

In order to achieve the above object, the long-distance automatic telephone call control device according to the present invention, a rectifier comprising a bridge diode for full-wave rectifying the input AC voltage to output a pulse voltage of a predetermined period, and to adjust the output pulse voltage A first transistor that is on / off controlled according to a voltage distribution resistor and a signal level applied to the base, and a second transistor that is turned on during an off operation of the first transistor to form a current path, and the second transistor is turned on The photodiode emits light according to the operation and the photocontroller is composed of a photocoupler which turns on the phototransistor and flows the current according to the light emission, and is connected to the base of the second transistor to adjust the operation time of the second transistor. And time constant adjusting means connected in parallel with each other, and a voltage output from the photocoupler. Zener diode to maintain a voltage of a resistor and a capacitor is composed of parts of the line interface unit connected in parallel with maintaining a constant voltage; The DC component removal capacitor is configured to remove the DC component from the pulse voltage from the rectifying unit, extract and output the frequency component signal of the dial signal of the telephone caller, and input the frequency component signal output from the DC component removal capacitor. A data converter comprising a DTMF decoder for decoding component signals; A clock generator for generating a clock signal having a predetermined frequency and inputting the DTMF decoder to a decoder of the DTMF in order to synchronize the operation of the DTMF decoder with a signal frequency supplied from a telephone station; An area code memory unit for storing a base area code of an installation place of the phone inputted through the phone; Extracts the local area code corresponding to the base area code outputted from the area code memory unit and operates the local area code, and compares each extracted local area code with the data signal input from the DTMF detoder. If it is determined that the first transistor to output a low level pass signal to turn off the first transistor, and if it is determined that there is no match, a high level cutoff signal to the first transistor is output to the first transistor And a central processing unit unit for turning on the transistor.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a connection system between a telephone line and a trunk line of a long distance automatic telephone call control apparatus according to the present invention.

As shown in the drawing, the long distance automatic telephone call control device is inserted into and connected between a telephone and a trunk line. The connection method includes a parallel connection to two trunk lines and a serial connection to one trunk line. The parallel connection method can minimize the deterioration of call quality due to the connection of a long distance automatic telephone call control device, but requires a separate operating power source to operate the call control device because the operating power supplied to the call control device is small. . On the other hand, in the serial connection method, the operation power supplied to the transmission control device is sufficient, so that no separate operation power is required, and the circuit is provided with a separate circuit for controlling the operation power supplied to the transmission control device. This can prevent the degradation of call quality. Therefore, the present applicant will be described for the way the long distance automatic telephone call control device is connected in series between the CO line and the telephone.

2 is a detailed circuit diagram of a long distance automatic telephone call control device designed to use both a serial connection method and a parallel connection method as necessary. However, as mentioned above, only the serial connection method will be described in practical terms. However, even in parallel mode, the operation of the long distance automatic telephone call control device according to the present invention should be understood that the same as the serial connection method.

First, the circuit configuration of the present invention will be described in detail with reference to FIG. Long distance automatic telephone call control device according to the present invention is largely the line interface unit 1, the data conversion unit 2, the clock generation unit 3, the area code memory unit 4, the central processing unit 5, and the switch It is roughly divided into parts (6).

At the first end of the line interface unit 1, two rectifying units D1 and D2, in which four diodes are bridged, are provided. The rectifier D2 on the upper side is for parallel connection to the telephone line and the trunk line, and the rectifier D1 on the lower side is for serial connection to the telephone line and the trunk line. The two rectifiers D1 and D2 are optional.

That is, when the serial connection method is used, only the lower rectifier D1 operates. On the contrary, when the parallel connection method is used, only the upper rectifier D2 operates. In addition, the capacitors SG1 and SG2 are connected to the two rectifiers D1 and D2, respectively. These capacitors SG1 and SG2 are intended to protect the rectifiers D1 and D2 by preventing surge current from flowing due to lightning.

A current adjusting resistor R1 is connected to the output terminal of the rectifying unit D1 connected in series with the telephone line and the trunk line, and a voltage distribution for distributing the output voltage from the rectifying unit D1 is connected between the resistor R1 and the ground. Dragon resistance R3 is provided. The capacitor C1 and the resistor R4 are connected in parallel to the connection points of the resistors R1 and R3 in order to adjust the time constant. A current adjusting resistor R5 and two switching transistors TR1 and TR2 are connected to both ends of the capacitor C1 and the resistor R4, and the photocoupler IC1 is connected between the resistor R5 and the transistor TR2. Is installed. In the present invention, the photocoupler uses an IC chip having four terminals. The capacitor C1, resistors R4, R5, two switching transistors TR1, TR2, and photocoupler IC1 form a line control section in this circuit. A zener diode DZ1, a resistor R6, and a capacitor C2 are connected in parallel to the output terminal (terminal 3) of the photocoupler IC1 to maintain a constant voltage regardless of the fluctuation of the output voltage of the photocoupler IC1. A constant voltage holding unit is formed. On the other hand, in the line interface unit 1, the switch unit indicated by JUMP1 and JUMP2 is currently connected to a switch to operate according to the serial connection method in the drawing. Alternatively, the switch may be switched to operate according to the parallel connection method according to a selection. It should be noted.

Next, the configuration of the data converter 2 will be described.

The data converter 2 is provided with a DTMF (Dual Tone MutiFrequency) decoder IC2 having 18 pins. The output terminal of the rectifying unit D1 of the line interface unit 1 is connected to the DC component removing capacitor C3 and the current adjusting resistor R7 via a switch unit JUMP2. It is connected to pin 2 of the DTMF decoder IC2 and is connected to pin 3 via a resistor R8.

Pins 1 and 4 of the DTMF decoder IC2 are commonly connected to each other. Pins 5, 6, and 9 are commonly grounded, and pins 7 and 8 are connected to the clock generator described below. In addition, pin 10 is connected to the operating power supply (Vcc) through a resistor (R15), and pins 11 to 14 are connected to a line for data output. Pin 15 is for confirmation signal output, and resistor (R9) is connected between pins 16 and 17 to set the reference voltage from the operating power source to match the frequency characteristics, and capacitor (C4) is connected between pins 17 and 18. It is.

The clock generator 3 preferably uses a crystal oscillator having three terminals. Pin 2 of the clock generator 3 is grounded, and pins 1 and 3 are connected to pins 7 and 8 of the DTMF decoder IC2. The clock generator 3 typically generates a clock signal of 3.75 MHz to synchronize the operation of the DTMF decoder IC2 with the frequency signal transmitted from the telephone station.

The area code memory section 4 is preferably composed of an electrically erasable and programmable ROM (IC3) EEPROM and has eight pins. Pins 1 to 3 are connected to lines for outputting the area code stored in the EEPROM (IC3). On pin 4, the operating power supply (Vcc) is supplied through the current regulation resistor (R14). Pin 5 is grounded, and pin 8 is directly supplied with the operating power supply (Vcc). Pins 6 and 7 are area code input pins.

Next, the configuration of the central processing unit 5 will be described.

The central processing unit 5 uses a one chip microprocessor IC4 in which the judgment and extraction program programmed by the present inventor is incorporated. The one-chip microprocessor (IC4) has 28 pins. Pin 1 and pin 2 are directly supplied with the operating power supply (Vcc), and are supplied to pin 4 through the capacitor (C7). Pin 6 is connected to pin 4 of the EEPROM (IC3). Pins 7, 8 and 9 are connected to the area code output lines respectively connected to pins 1, 2 and 3 of the EEPROM (IC3). Pins 10 to 13 are connected to data output lines connected to pins 11 to 14 of the DTMF decoder IC2 of the data converter 2, respectively. Pin 14 is connected to pin 15 of the DTMF decoder (IC2). Pin 15 is connected to the operating power supply (Vcc) through the current regulating resistor (R13). The pin 16 is connected to the light emitting diode LED1 and the current regulating resistor R12.

Pin 17 is connected to the base of the switching transistor TR1 of the line interface unit 1 through a current regulating resistor R16. Pin 18 is connected to the operating power supply (Vcc) through the current control resistor (R15) and at the same time to pin 10 of the DTMF decoder (IC2). Pins 19 to 26 are used to input the one chip microprocessor's decision and extraction operation program into the one chip microprocessor (IC4). Pin 27 is connected to pin 1 of the clock generator 3 via a capacitor C5. Pin 28 is connected to the operating power supply (Vcc) through a resistor (R10) and a resistor (R11). The zener diode ZD2 and the capacitor C5 are connected between the resistor R10 and the resistor R11. These devices R10, R11, ZD2, and C5 set an operation start time of the one-chip micropressor IC4.

Finally, the switch means SW1 is connected to pin 15 of the one-chip microprocessor IC4 in the switch section 6 of the long distance automatic telephone call control apparatus according to the present invention. The switch means (S1) is composed of a push-pull button using a key and the switch is on / off operation by the push-pull operation according to the rotation of the key.

The circuit configuration of the long distance automatic telephone call control device according to the present invention has been described above, and the circuit operation will be described in detail below.

Long distance automatic telephone call control device of the present invention is to block or release the long-distance call according to the rotation direction of the key mounted on the back of the device case.

First, an operation of blocking a call will be described.

When the key is rotated in the blocking direction, the switch means SW1 is opened, and thus the operating power source Vcc is supplied to pin 15 of the one-chip microprocessor IC4 of the central processing unit 5 through the current regulating resistor R13. The one-chip microprocessor IC4 is ready to execute the judgment operation. The one-chip microprocessor (IC4) has a built-in ROM that contains data determination and extraction programs and national area codes. In addition, the area code of the area (base area) where the telephone is located is entered in the EEPROM (IC3). In this state, when the telephone caller dials an arbitrary area code, the DC signal is removed from the capacitor C3 of the data converter 2 and becomes a frequency component signal so that the DTMF decoder of the data converter 2 Pins 2 and 3 of IC2) are decoded in hexadecimal and then output to pins 11-14 of the DTMF decoder (IC2). The decoded data signal is input to pins 10 to 13 of the one-chip microprocessor IC4 of the central processing unit 5. At the same time, the base area number stored in the EEPROM (IC3) from the pins 1 to 3 of the EEPROM (IC3) of the area code memory unit 4 is input through pins 7 to 9 of the one-chip microprocessor (IC4). In the one-chip microprocessor (IC4), when the input base area code is input, the local area code (local call charge area code) for the base area code is extracted according to the execution of the area code extraction program embedded in the ROM.

Then, according to the execution of the judgment program, the data signal input from the DTMF decoder IC2 (area number dialed by the telephone caller) and the extracted short-range area number are compared and judged, and the data inputted by the telephone caller is determined. If there is a match between the signal and the extracted local area codes, the one-chip microprocessor IC4 generates a low level signal through pin 17. Since the low-level signal does not turn on the switching transistor TR1 of the line interface unit 1, the pulsation (direct current) voltage output from the rectifying unit D1 is not bypassed toward the switching transistor TR1, and other switching is performed. The photo coupler IC1 is applied to the base of the transistor TR2 to turn it on, so that a current flows through the photocoupler IC1 so that a constant voltage formed in the constant voltage holding units DZ1, R6, and C2 can be transmitted to the telephone station through the trunk line. In other words, if the caller dials the area code of the local toll coverage area in the base area, for example, if the telephone installation area (base area) is Seoul (area code 02), the caller is within 30 km radius of Seoul. When dialing any one of the local area codes (eg, Anyang-si (area code 0343), Seongnam-si (area code 0342), etc.), the caller sends a low-level pass signal from the one-chip microprocessor (IC4). You can effectively talk to the other party.

However, as a result of the determination by the one-chip microprocessor IC4, if the data signal inputted by the telephone caller and the extracted local area codes do not match, the one-chip microprocessor IC4 sends a high level signal through pin 17. This high level signal turns on the switching transistor TR1 of the line interface unit 1. Therefore, the DC voltage output from the rectifier D1 is bypassed through the switching transistor TR1. Therefore, since the DC voltage output from the rectifying unit D1 is not applied to the photocoupler IC1, no current flows through the top coupler, and thus, the dialing signal of the telephone caller cannot transmit the trunk line. That is, when the caller dials a long distance area code outside the local call coverage area of the base area, the WinChip microprocessor (IC4) outputs a high level cutoff signal to block the caller from talking to the other party.

Next, an operation of releasing call control will be described.

When the key is rotated in the release direction, the switch means SW1 is closed. Therefore, since the operating power supply Vcc is bypassed to the ground through the resistor R13, the operating voltage is not applied to the one-chip microprocessor IC4 of the central processing unit 5, and the determination and extraction program of the one-chip microprocessor IC4 is executed. As a result, a low level signal is output through pin 17 for any dialing signal from the caller, so that a call can be made anywhere in the country.

In addition, in the present invention, it is possible to input only the 8888 and # through the telephone to enable only the telephone reception function.

Until now, the detailed description of the present invention has described a technique of passing a short distance area code to which a local call charge is applied and blocking other long distance area codes.

The long distance automatic telephone call control apparatus according to the present invention also has functions such as 700 station pay service blocking, emergency call and wireless call (beep) passage, and wireless telephone (mobile phone) call blocking of the conventional long distance automatic telephone call control apparatus. . These functions have been omitted in the present specification because they can be achieved by conventional techniques.

On the other hand, the long-distance automatic telephone call control device according to the present invention has been described with respect to blocking the long-distance area code of the local area code within 30 km from the base area, but is not limited to this modification without departing from the spirit and scope of the present invention. Or it will be apparent to those skilled in the art that modifications are possible. For example, although the current authorities only apply the local call charges within 30 km from the base area, the present invention is still applicable to such areas even if the area of 30 km or more is extended later, for example, in Seoul, Gyeonggi-do, Chungcheongbuk-do, etc. It should be appreciated.

Claims (5)

On / off control according to the rectifier comprising a bridge diode for full-wave rectifying the input AC voltage to output a pulse voltage of a predetermined period, the voltage distribution resistor for adjusting the output pulse voltage, and the signal level applied to the base A second transistor which is turned on when the first transistor and the first transistor are turned off to form a current path, and a photodiode emits light according to the on-operation of the second transistor, and the phototransistor is turned on according to the light emission so that a current A line controller configured to flow a photo coupler, a time constant adjusting means connected to a base of the second transistor and having a capacitor and a resistor connected in parallel to adjust an operation time of the second transistor, and a voltage output from the photo coupler. Zener diode, resistor and capacitor are connected in parallel to maintain the voltage at a constant level. Line interface unit consisting of parts and maintain pressure; The DC component removal capacitor is configured to remove the DC component from the pulse voltage from the rectifying unit, extract and output the frequency component signal of the dial signal of the telephone caller, and input the frequency component signal output from the DC component removal capacitor. A data converter comprising a DTMF decoder for decoding component signals; A clock generator for generating a clock signal having a predetermined frequency and inputting the DTMF decoder to a decoder of the DTMF in order to synchronize the operation of the DTMF decoder with a signal frequency supplied from a telephone station; An area code memory unit for storing a base area code of an installation place of the phone inputted through the phone; Extracting a local area code for one or more local call charges corresponding to the base area code output from the area code memory unit, comparing each extracted local area code with the data signal inputted from the DTMF decoder If it is determined that the first transistor outputs a low level pass signal to the first transistor to turn off the first transistor, and if it is determined that there is no match, a high level cutoff signal to the first transistor to output the first transistor Long distance automatic telephone call control device, characterized in that consisting of a central processing unit to turn on. 2. The long distance automatic telephone call control device according to claim 1, further comprising switch means for controlling a supply of operating power for operating the central processing unit. The long distance automatic telephone call control device according to claim 1, wherein said central processing unit is a one-chip microprocessor. The apparatus of claim 1, further comprising an operation start time setting unit in which a resistor, a zener diode, and a capacitor are connected in parallel to set an operation start time of the central processing unit in the central processing unit. Control unit. The apparatus of claim 2, wherein the switch means comprises a key for blocking a long distance automatic telephone call when the switch means rotates in one direction and releasing the blocking operation when rotating in the other direction.