KR19980073503A - Locks on personal computers - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a locking device for a personal computer, and more particularly, to a locking device for a personal computer capable of maintaining the security of the personal computer by locking the keyboard and locking the mouse when the locking switch is turned on. .

The locking device provided in the conventional personal computer only locks the keyboard, so that in the current computing environment where GUI environment is most, the data stored in the hard disk can be easily accessed using only the mouse. Since data can be easily leaked by the mouse, there is a problem that the security of the system is lacking.

According to the present invention, when the locking device of the personal computer is operated, the keyboard is locked and the mouse is also locked, thereby preventing data leakage by the mouse, thereby improving the security effect of the personal computer.

Description

Locks on personal computers

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a locking device for a personal computer, and more particularly, to a locking device for a personal computer capable of maintaining the security of the personal computer by locking the keyboard and locking the mouse when the locking switch is turned on. .

In general, a personal computer these days is a popular graphics operating system, for example, Windows 3.1 or Windows 95, so that users do most of the work using the mouse in the GUI (Graphic User Interface) environment, Input the word processor or other data using the keyboard, and input and output general data, that is, save the data stored on the hard disk to a floppy disk, or vice versa. Accessing peripheral devices such as copying or printing can be done conveniently using the mouse. On the other hand, a conventional personal computer is generally equipped with a lock device, and when the lock device is operated, it is designed to prevent the leakage of information by making the keyboard inoperable and preventing a third party from using the computer illegally. .

As described above, the locking device provided in the conventional personal computer locks only the keyboard, so that in the current computing environment where GUI environment is most, the data stored in the hard disk can be easily accessed using only the mouse. Even if it is activated, data can be easily leaked by the mouse, and thus there is a problem that the security of the system is lacking.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. When the locking device of the personal computer is operated, the keyboard is locked and the mouse is locked, thereby preventing the mouse from being used and preventing the leakage of data by the mouse. An object of the present invention is to provide a lock of a personal computer.

In order to achieve the above object, the present invention provides a locking device for a personal computer, comprising: a lock switch outputting or blocking a lock signal according to a user's operation; A keyboard control unit which inputs / outputs a keyboard, a clock, and keyboard data to each other, mutually inputs and outputs a mouse, a clock, and mouse data, and blocks data input / output with the keyboard in response to a lock signal applied from the lock switch; A keyboard connector which connects the keyboard controller with a keyboard to input and output clocks and keyboard data; A mouse connector which connects the keyboard control unit and a mouse to input and output clock and mouse data; A three-state buffer that operates when a predetermined signal is applied to a control terminal according to the operation of the lock switch to maintain a clock of a mouse connected to the keyboard control unit at a predetermined signal level; A resistor for adjusting the level of the voltage applied to the control terminal of the tri-state buffer; The keyboard controller may include a plurality of inverters that prevent the reverse flow of signals when the keyboard and the mouse connected to the keyboard connector and the mouse connected to the mouse connector interoperate with each other.

1 is a block diagram of a locking device of a personal computer according to the present invention;

2 is an operation timing diagram of a mouse according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

10: keyboard control unit 20: keyboard connector

30: mouse connector 40: lock switch

50: tri-state buffer R: resistance

I1 to I4: Inverter

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

Locking device of a personal computer according to the present invention, as can be seen in Figure 1, the keyboard control unit 10, the keyboard connector 20, the mouse connector 30, lock switch 40, three-state buffer ( 50), resistor R and a plurality of inverters I1 to I4.

The keyboard controller 10 inputs / outputs a keyboard, a clock, and keyboard data to each other, inputs / outputs a mouse, a clock, and mouse data to each other, and receives a data input / output with the keyboard in response to a lock signal applied from the lock switch 40. Block it. The keyboard connector 20 connects the keyboard controller 10 and the keyboard to input and output clock and keyboard data, and the mouse connector 30 connects the keyboard controller 10 and the mouse to input and output clock and mouse data. To help. The lock switch 40 outputs or blocks the lock signal to the keyboard control unit 10 in response to the user's operation. The tri-state buffer 50 operates when a predetermined signal is applied to the control terminal according to the operation of the lock switch 40 to maintain the clock of the mouse connected to the keyboard controller 10 at a predetermined signal level. The resistor R adjusts the level of the voltage applied to the control terminal of the three-state buffer 50, and the plurality of inverters I1 to I4 are keyboard and mouse connectors in which the keyboard controller 10 is connected to the keyboard connector 20. When the clock and data are inputted and outputted to the mouse connected to the 30, the reverse flow of the signal is prevented.

Meanwhile, the mouse is generally classified into a serial type and a PS / 2 type according to an interface method. The serial type is the most commonly used mouse. The mouse is connected to a serial port RS-232C and used as a PS / 2. The type is a method used in the IBM PS / 2 series and some PC series using a port used by the keyboard, since the PS / 2 keyboard control unit 10 can directly control a device such as a mouse or trackball. to be. They have special serial ports, have a separate PS / 2 mouse connector connected to the motherboard, and are controlled by the keyboard control unit 10 together with the keyboard. Therefore, according to the embodiment of the present invention, the mouse is applied to the PS / 2 type mouse whose connector structure is the same as that of the keyboard connector rather than the general serial mouse. On the other hand, most of the current IBM PC compatible series support PS / 2 type mouse port, and of course, a serial interface mouse can be used. The current trend is that most PS / 2 type connectors are supported by PC motherboards, so there is no need to purchase a separate connector, and most PC users are using PS / 2 type mice rather than serial mice.

The operation of the present invention configured as described above will be described in detail with reference to the accompanying drawings.

First, the operation of locking the keyboard according to the operation of the lock switch 40 is the same as the conventional operation.

That is, when the lock switch 40 is turned off, the high level signal supplied from the Vcc is applied to the LOCK port of the keyboard control unit 10, so that the keyboard control unit 10 receives the keyboard clock out (KCO) and the keyboard clock in (KCO). By activating the KCI), keyboard data out (KDO), and keyboard data in (KDI) ports, the keyboard side and keyboard data and clocks can be input and output, so that the user can use the keyboard. Thereafter, as the user turns on the lock switch 40, since the power supplied from the Vcc flows through the ground terminal, a low level signal is applied to the LOCK port side of the keyboard controller 10, whereby the keyboard controller 10 ) Disables the Keyboard Clock Out (KCO), Keyboard Clock In (KCI), Keyboard Data Out (KDO), and Keyboard Data In (KDI) ports, making it impossible to input and output keyboard and keyboard data and clocks. Even if is inputted, the data is not applied to the keyboard control unit 10, and the personal computer cannot be operated through the keyboard. Here, if the LOCK port is recognized at a low level, the keyboard interface is blocked in the keyboard controller 10 so that no data is transmitted to the host. However, the signal interfaced through the keyboard connector 20 operates by maintaining the same waveform as before.

Meanwhile, the operation of locking the mouse according to the operation of the lock switch 40 will be described below.

First, when the lock switch 40 is turned off, a high level signal supplied from Vcc is applied to the LOCK port of the keyboard control unit 10 and the control terminal of the three-state buffer 50, so that the three-state buffer is not activated. Instead, the keyboard controller 10 activates the keyboard clock out (KCO), the keyboard clock in (KCI), the keyboard data out (KDO), and the keyboard data in (KDI) port as described above, and at the same time, the mouse clock out. By enabling (MCO), Mouse Clock In (MCI), Mouse Data Out (MDO), and Mouse Data In (MDI) ports, the mouse side and mouse data and clock can be input and output. It becomes available. At this time, between the keyboard control unit 10 and the mouse, a protocol for transmitting 8-bit mouse data accurately in synchronization with the mouse clock is used. As shown in the mouse operation timing diagram of FIG. In order to achieve this, a certain amount of time is required for the A and B states. In this case, the B state is a state in which the signal line is kept high for transmitting mouse data, thereby preparing to synchronize accurately. The A state is necessary to make the B state for the next data transmission after the data transmission is completed. Therefore, no data transmission is made in the A state.

Thereafter, as the user turns on the lock switch 40, since the power supplied from the Vcc flows through the ground terminal, as described above, a low level signal is applied to the LOCK port side of the keyboard controller 10. The keyboard controller 10 disables the keyboard clock out (KCO), the keyboard clock in (KCI), the keyboard data out (KDO), and the keyboard data in (KDI) ports, thereby preventing input and output of the keyboard, keyboard data, and clock. Thus, even if the user inputs the keyboard, the data is not applied to the keyboard control unit 10 side, so that the personal computer cannot be operated through the keyboard. In addition, as the user turns on the lock switch 40, since the power supplied from the Vcc flows through the ground terminal, a low-level signal is applied to the control terminal of the tri-state buffer 50, whereby the tri-state buffer ( 50 is activated, the mouse clock line connected to the keyboard control unit 10 and the mouse is connected to the ground terminal to maintain a low level. Therefore, since the clock line of the mouse maintains the A state at the low level, the keyboard control unit 10 and the mouse do not input or output any data, so that the personal computer cannot be operated through the mouse like the keyboard.

As described above, when the locking device of the personal computer is operated, the keyboard is locked and the mouse is locked, thereby preventing data leakage by the mouse, thereby improving the security effect of the personal computer.

Claims (1)

A lock device of a personal computer, comprising: a lock switch (40) for outputting or blocking a lock signal corresponding to a user's operation; A keyboard control unit which inputs and outputs a keyboard, a clock, and keyboard data to each other, inputs and outputs a mouse, a clock, and mouse data to each other, and blocks data input and output to and from the keyboard in response to a locking signal from the lock switch 40 ( 10); A keyboard connector 20 connecting the keyboard controller 10 to the keyboard to input and output clocks and keyboard data; A mouse connector 30 connecting the keyboard controller 10 and a mouse to input and output clock and mouse data; A three-state buffer 50 that operates when a predetermined signal is applied to the control terminal according to the operation of the lock switch 40 to maintain the clock of the mouse connected to the keyboard control unit 10 at a predetermined signal level; A resistor (R) for adjusting the level of the voltage applied to the control terminal of the tri-state buffer (50); When the keyboard controller 10 inputs / outputs a clock or data to a keyboard connected to the keyboard connector 20 and a mouse connected to the mouse connector 30, a plurality of inverters I1 to I4 which prevent the reverse flow of signals. Locking device of a personal computer, characterized in that it comprises a).