JPH0249071B2 - DENWAGATATANMATSUSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a telephone type terminal device capable of voice calls and data communications.

(b) Conventional technology In recent years, telephone-type terminal devices have begun to be widely adopted in credit card verification and banking operations. Application of
An overview of various telephone terminal devices is disclosed.

Generally, in order to enable data communication in such terminal devices, the control section is composed of a microprocessor and its peripheral circuits, and this control section is supplied with DC power voltage obtained from a commercial power supply. .

On the other hand, the dialing circuit that sends the dialing signal corresponding to the telephone number to the telephone line is the pulse dialer of "Mostek Communication Element Data Book".
As disclosed in the description of ICMK50992(N), the power supply voltage is usually obtained from the telephone line.

(c) Problems to be solved by the invention Telephone-type terminal devices are often used in financial services as mentioned above, so unauthorized use by third parties must be avoided as much as possible. Therefore, a specific mode is designated by a predetermined key operation, and during this specific mode,
By stopping the dialing function under the control of the microprocessor, data communication by third parties other than store owners can be prevented.

However, in conventional terminal devices, the power to the microprocessor is obtained from the commercial power supply, and the power to the dial circuit is obtained from the telephone line, so the specific mode mentioned above is canceled when the power plug is removed. In this state, it is possible to make a voice call. Therefore, a new problem has arisen in that a third party uses the telephone without permission and makes long-distance or international calls, resulting in surprisingly high telephone charges.

(d) Means for Solving Problems The present invention provides a latching relay circuit that is set or reset by a control unit in response to a predetermined key operation on a keyboard, and a latching relay circuit that is set or reset by a control unit in response to a predetermined key operation on a keyboard, and A means for stopping the dial function of the dial circuit is provided.

(e) Effect In the present invention, when a predetermined key is operated on the keyboard, a latching relay circuit is set, and this latching relay circuit maintains its state regardless of whether the power is turned on or off, so that the dial function can be maintained even after the power is turned off. will remain suspended and you will not be able to make voice calls.

(f) Embodiment FIG. 1 is a block diagram showing the overall configuration of a telephone terminal device according to the present invention, in which 1 is a diode bridge circuit connected to a telephone line 2, and 3 is a piezoelectric circuit for receiving a call signal. A ringer detection circuit drives the buzzer 4; 5 is a switch inserted into the telephone line 6; 7 is a communication circuit connected to the telephone line 6; 8 and 9 are a transmitter and receiver; 10 is a dial pulse switch 11 that turns on and off. a pulse dialer that controls and sends out dial pulses corresponding to a telephone number; 12 corresponds to a telephone number;
A tone dialer 13 that sends out a DTMF (dual tone multi-frequency) signal is connected to the telephone line 6, and the output voltage is set to the power supply voltage V _DS
This is a regulator circuit that supplies the dialers 10 and 12 and the telephone communication circuit 7 as a main terminal.

In addition, 14 is a keyboard equipped with multiple operation keys such as function keys, character keys, and numeric keys;
5 is a CPU that constitutes a control unit together with I/O interfaces 16 and 17; 18 is a display device; 19 is a RAM 20 for storing communication data transmitted and received with the host computer;
A memory system consisting of an EPROM 21 that stores programs and an E ² PROM 22 that serves as a non-luminous generation memory that stores data that you do not want to erase even when the power is turned off, such as telephone numbers, and a memory system 23 that converts communication data and telephone signals. modem, 24 is I/O
A dialer control circuit 25 controls the dialing functions of the pulse dialer 10 and tone dialer 12 in accordance with the output signal of the interface 16, and a dialer control circuit 25 inputs commercial power voltage through a power plug 26;
CPU15, I/O interface 16 and 1
7. Supply voltage V _DD to each part of the memory system 19, etc.
The dialer control circuit 24 receives the power supply voltage from the regulator circuit 13.
V _DS is also supplied.

By the way, as the pulse dialer 10 and the tone dialer 12, for example, the dialers ICMK50992 and MK5089 manufactured by Mostitsu may be used, and these ICs have terminals for controlling the dial function on pin 17 and pin 2, respectively. When the input signal to pin 17 is at "H" level or in an open state, and when the input signal to pin 2 is at "L" level, the dialing function of each dialer is stopped.

FIG. 2 is a circuit diagram showing a specific configuration of the dialer control circuit 24.
The collector is connected to pin No. 2, the emitter is grounded, and the base is connected to the power supply potential through resistors 25 and 26.
Switching transistor 27 connected to V _DS
and a switching transistor 30 whose collector is connected to pin 17 of the pulse dialer 10, whose emitter is grounded via a switch 28, and whose collector is connected to the power supply potential _VDS via resistors 29 and 26; A switching transistor 31 whose collector is connected to the base of 30 and whose emitter is grounded, and resistors 25 and 2
The output is connected to the connection point P of 9, and the selection switch 32 selects between a pulse dialer and a tone dialer, and a signal from the I/O interface 16.
A latching relay circuit 33 is provided which is set and reset by CN1 and CN2, and the C terminal of the contact 34 of the latching relay circuit 33 is connected to the power supply potential V _DS via a resistor 35, The M terminals of diodes 36 and 37
are connected to the bases of switching transistors 27 and 31, respectively.

Next, the operation of this embodiment will be explained.

Normally, the latching relay circuit 33 is in a reset state, and the contact 34 is coupled to the B side. Therefore, the power supply voltage V _DS is not supplied to the terminal M. In this state, when the selection switch 32 is set to the DTMF side as shown in the figure, the connection point P between the resistors 25 and 29 is grounded, so the switching transistors 27 and 30 are turned off, and both dialers 12,
Input signal of pin 2 and pin 17 of 10 and
Both OHTs are in an open state. Therefore, the tone dialer 12 becomes operational, and the pulse dialer 10 becomes inactive, stopping the dialing function.

If the selection switch 32 is set to the DP side, the connection point P
Since the power supply voltage V _DS is supplied to through the resistor, the switching transistors 27 and 30 are both turned on, and the input signal and OHT become "L". Therefore, in this case, the tone dialer 12 becomes inactive and the pulse dialer 10 becomes operable.

In this way, one of the dialers is selected depending on the selection switch 32.

However, when a predetermined key operation is performed on the keyboard 14,
For example, if you specify a specific mode by operating the keys ENTER → A3 → □1, the CPU 15 responds to this key operation and selects the I/O interface 1.
6's output signal CN1 is set to "H". Then, the switching transistor 38 turns on, current flows through the set coil 39, and the latching relay circuit 3
3 is set, and the contact 34 is connected to the M side.
Therefore, the power supply voltage V _DS is applied to the bases of the switching transistors 27 and 31 via the resistor 35, the latching relay circuit 33, and the diodes 36 and 37, and these transistors are turned on. is turned off. Therefore, the input signal becomes "L", the input signal OHT becomes open, and both dialers 10 and 12 become inactive, stopping the dialing function.

Once the latching relay circuit 33 is set, it maintains the set state even if the power supply voltage V _DD from the power supply circuit 25 is cut off, so that the power supply voltage V _DD remains unchanged.
If a specific mode is set while power is being supplied, the dialing functions of dialers 10 and 12 will remain stopped even if the power plug 26 is removed.
Data communication and voice calls will be impossible.

To cancel this specific mode, perform a predetermined key operation, for example, ENTER → A3 → □0, and the CPU 15 will respond to this key operation and send a signal.
In order to set CN2 to "H" level, the switching transistor 40 is turned on and the reset coil 41 is turned on.
A current flows through, the latching relay circuit 33 is reset, and the contact 34 is connected to the B side.
Therefore, one dialer selected by the selection switch 32 returns to the operable state.

(g) Effects of the invention According to the present invention, if a predetermined key operation is performed,
Even when the supply of power supply voltage to the microprocessor and its peripheral circuits is cut off, the dialing function of the dialing circuit continues to be stopped, so a third party may make long-distance calls, international calls, etc. for private purposes in this state. It is possible to prevent third parties from making unnecessary phone calls.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention, and FIG. 2 is a detailed circuit diagram of the main parts of this embodiment. Explanation of main drawing numbers, 2...Telephone line, 10...Pulse dialer, 12...Tone dialer, 1
3...regulator circuit, 14...keyboard,
15...CPU, 24...Dialer control circuit,
25...power supply circuit, 33...latching relay circuit.

Claims (1)

[Claims] 1 A keyboard equipped with a plurality of operation keys, a control unit that operates using a first power supply voltage obtained from a commercial power supply, and a dial circuit that operates using a second power supply voltage obtained from a telephone line and sends a dial signal to the telephone line. a latching relay circuit that is set or reset by the control section in response to a predetermined key operation on the keyboard; 1. A telephone-type terminal device comprising: means for stopping a dialing function.