KR960011215B1 - Facsimile control circuit and method - Google Patents

Abstract

The circuit for preventing an unauthorized person from using a fax. or a phone, includes a trans former(NT1) linked to a line to detect a DTMF(Dual Tone Multi Frequency), a Zener diode(ZD1) and a resistor linked in parallel to the NT1, a DTMF decoder decoding received data from a resistor(R2), a CPU linked to a relay, the relay linked to a switch opening or shortening the lines. The control method comprises the steps of: disabling all functions of the fax. for an unauthorized password; hanging up on the line in case of "0" for the first dial; enabling the line in case of not "0" for the first dial.

Description

Fax control circuit and control method

1 is a connection diagram of a conventional fax and a telephone.

2 is a control circuit diagram using a fax of the present invention.

3 is a flowchart of a method for controlling fax use.

* Explanation of symbols for main parts of the drawings

1 connector 2 network control unit

3: CPI 4: Phone

5: DMP decoder

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the use of faxes, and more particularly, to a fax use control circuit and a control method suitable for preventing unauthorized persons from using faxes and fax telephones in the absence of a person in charge of a fax.

In general, the fax apparatus used is provided with a password input device so that only a specific person can use the fax. When the user inputs the correct password, the fax apparatus becomes available for faxing and transmitting and receiving documents.

When using such a fax machine, you enter a specific menu and register a password while the fax is in operation.

If the person in charge has registered a password, in the absence of the person in charge, another person puts the manuscript to send a fax, dials the other party's phone number, and a message prompting the user to enter the password appears on the LCD display.

At this time, transmission is possible only when key input of four or more digits corresponding to the password is possible. If key-entering wrong number, a message or alarm sounds that the password is wrong and transmission is impossible.

However, such a conventional fax machine is not a complete fax permission control device because it is impossible to send a document through a fax without a password in the absence of the person in charge of the fax, but a telephone call or a copy is possible.

Therefore, since a general fax line is installed in a long distance / overseas call, a telephone can be used even if a fax cannot be transmitted, and thus an increase factor of a telephone charge due to a long distance / oversea call exists.

Accordingly, an object of the present invention is to solve the deficiencies according to the conventional fax machine as described above, if the password entered by the fax user does not match the registered password, make the fax unusable and make a telephone call. The present invention provides a control circuit and a control method for using a fax machine to detect a DTMF (Dual Tone Multi Frequency Tone) and cut a line in a long distance / international telephone except a downtown.

FIG. 2 is a block diagram of the control circuit for fax use according to the present invention, in which a transformer NT1 for detecting DMP is connected to the line 6 connected to the telephone 4, and the secondary side of the transformer NT1 is connected. The Zener diode ZD1 and the resistor R1 are connected in parallel, and the resistor R2 is connected to the common connection point, and input to the demultiplexer decoder 5.

In addition, the output signal of the DMP decoder 5 is applied to the CPI 3, and the CPI 3 connects the relay U1 to the output terminal P1 so that the line 6 is connected by the switch SW1. Configure to open or short.

On the other hand, Figure 3 is a control flow diagram for a method for restricting use of a fax according to the present invention. If a password is registered, the step of disabling all the functions of a fax is disabled. If it is confirmed to be 0, the relay U1 is operated to cut the line 6, and if the first dial number is not 0, the call is enabled.

Referring to the operation and effects of the fax use control circuit of the present invention configured as described above in detail as follows.

First, if you want to use the fax with the password registered by the person in charge of the fax, you have to enter the registered password. If the entered number matches the saved password, all the functions of the fax are operated normally and the entered number is stored. If the password does not match, the fax only performs the receiving operation.

On the other hand, if a password is not entered and attempts to make a call using the telephone 4, the fax detects the D-Tamp tone through the D-MP decoder 5 to determine whether the first number is 0. In the case of the telephone dial used, if the first signal is 0, this is a long distance or overseas call, so the CPI 5 outputs the relay U1 driving signal through the output terminal P1 so that the switch SW1 is opened so that the telephone line 6 is open. Will be cut.

However, in the case of the local call, even if the fax detects the DFM tone by the DMP decoder 5, since the first dial number does not start with 0, the local call is possible because the line 6 is not cut.

Therefore, the present invention, unlike the lock of the conventional fax machine, not only controls the fax transmission, but also manages copying or telephone calls, so that the person in charge of the fax can manage the fax machine efficiently and reduce the telephone call volume, thereby reducing the telephone charges. You can get it.

As described above, the present invention provides an effect of efficiently managing a fax and a fax phone.

Claims (2)

A transformer NT1 for detecting a DMT tone is connected to a line 6 connected to the telephone 4, and a zener diode ZD1 and a resistor R1 are connected in parallel to the secondary side of the transformer NT1, and The common connection point is input to the DMP decoder 5, and the output terminal of the DMP decoder 5 is connected to the CPI 3, and the CP 3 has an output terminal P1 open to the telephone line 6. And a switch (SW1) for opening / shorting a line (6) connected to the relay (U1) for short-circuit. If a password has been registered, disable all the functions of the fax; if you pick up the phone, detect the dial number to see if the first dial number is zero; if it is zero, cut the telephone line; if the first dial number is zero, If not, the fax use control method, characterized in that consisting of steps that enable the call.