JPH03156518A - Keyboard controller - Google Patents

Abstract

PURPOSE:To obtain a keyboard controller free from contradiction between normal key input and special key input by sending a corresponding key code to an I/O port different between the normal state and the special state of a one-chip microcomputer by transmitting means different between them. CONSTITUTION:When a general key 3 is depressed in the normal state, its key code is sent to an I/O port 1 of a one-chip microcomputer 4 by a general key code transmitting means 5 and is received by a CPU 15. If a special key 2 is depressed in the normal state, the special state is set, and this setting is reported to a CPU 15 through an I/O port 2 of the microcomputer 4 by a special key state transmitting means 6. When another key is depressed in such a state, a corresponding assigned special key code is reported to the CPU 15 through an I/O port 3 of the microcomputer 4 by a special/general key state transmitting means 7. Consequently, the system is controlled without an influence on an application operated in the computer.

Description

[Detailed Description of the Invention] [Industrial Application Field J] The present invention relates to a control system for a keyboard of a portable computer having electronic devices such as a CPU, memory, input/output device, external storage device, display device, keyboard, power supply device, etc. involved in
More particularly, it relates to a key code or status transmitting device for a keyboard with special key switches.

[Prior Art 1] A keyboard is the most common input device in computers. The keyboard includes a plurality of key switches arranged at appropriate positions, each of which can electrically detect on/off, and a keyboard that monitors the keyboard switches and detects whether the key switches are on or off. Generally, the key switch is made up of a one-chip microcomputer whose main body knows the key code that corresponds to the on/off state of each key switch when it is pressed or released.

The l-chip microcomputer has ROM, RAM, I/O, C
It consists of a PU core, and is characterized by its ability to execute programs and perform input/output operations.

Using a 1-chip microcomputer to control the keyboard is the cheapest way to improve the throughput of the main body's CPU.

The key switch has an electrically shorted state and an oven state. When the key switch is pressed, the electrically shorted state is entered, and when the key switch is released, the electrically oven state is entered. An electrically shorted state is called on, and an electrically oven state is called off.

When one key switch is pressed on the keyboard,
The key switch is turned on, and the L chip microcomputer recognizes that the key switch has been pressed.
1. The chip microcomputer sends information indicating that the key switch has been pressed to the CPU.

Further, when a key switch that has been pressed on the keyboard is released, the key switch is turned off, and the one-chip microcomputer recognizes that the key switch has been released. The l-chip microcomputer sends information indicating that the key switch has been released to the CPU.

In this manner, the CPU of the main body can know whether a key switch has been pressed or released.

The keyboard of a conventional computer typically has about 100 key switches and is connected to the computer main body by a cable. In such a keyboard configuration, the on/off status of the key switch is generally sent to the main computer as coded information. This code is called a key code, and the means of transmitting the key code is generally serial communication.

For example, in the case of a keyboard with 100 key switches, 200 key codes are required to notify the on/off status of each key switch. These key codes are then sent to the computer main body via serial communication such as R5-232C.

The basic operational relationship between the computer keyboard and the computer itself is as described above.
On the other hand, what is the form of a computer?

Due to the miniaturization and reduction in power consumption of electronic components related to computers, as well as improvements in actual technology, the CPU, memory, input/output devices, external storage devices, display devices, keyboards,
The power supply device is compactly layered. So-called portable computers have come to be realized.

In portable computers, the keyboard is often housed in the same case as the computer itself, and the means of transmitting the key code is not something like serial communication, but is sent directly from the l-chip microcomputer to the CPU. . That is, the I10 port of the one-chip microcomputer is connected to the I/O port of the CPU via a data latch, buffer, etc., and the key code is sent via these I/O ports.

On the other hand, in portable computers, in order to further improve portability and usability, the keyboard is required to have a function for controlling the system in addition to the conventional functions.

That is, there is a strong demand for changing CPU speed, switching display devices, and controlling for lower power consumption through the keyboard.

For example, in the past, changing the CPU speed or switching the display device was done using a specially provided switch, but in order to reduce the space for the switch,
In order to easily control these systems, it is conceivable to control these systems by inputting from a keyboard.

In order to explain this situation in more detail, a change in CPU speed will be taken as an example and explained according to FIG.

In FIG. 4, 101 is a keyboard switch, 102
is a 1-chip microcomputer, 103 is a scan line, 104 is a lead line, 105 is a data buffer, 106 is a status buffer, 107 is a system bus, tOS is a CPU, 1
09 is RAM, 110 is a key buffer, 111 is a key buffer pointer, 112 is a key status flag, 1
13 is a control key, 114 is a shift key, 115
is the H key, and 116 is the S key.

The keyboard switch (101) is composed of a plurality of key switches, and each key switch is connected to the scan line (103).
) is connected one end of that switch to one of the lines formed by the lead, and the other end is connected to said lead! ! (104)
Connected to one of the examples configured by

The l-chip microcomputer (102) connects the scan line (1
04), and turn on/off the key switch connected to the selected row using the lead wire (1).
It can be electrically recognized by reading 02). When a certain key switch is pressed, the l-chip microcomputer outputs the key code corresponding to the key switch to the data buffer (105), and at the same time outputs the key code corresponding to the key switch to the data buffer (105) of the status buffer (106).
The buffer empty flag indicating that the key code of 105) is set to 1.

When the buffer empty flag becomes 1, the C
A keyboard interrupt occurs to PU (108),
A keyboard service routine is activated to read the key code contained in the data buffer (105), and the read key code is transferred to the key buffer (110) pointed to by the key buffer pointer (111). can be placed inside. The key buffer pointer (111) is then updated to point to the next location of the key buffer.

On a keyboard, the shift key and control key are called status keys, and are stored in the key buffer (110).
For example, if the control key (113) is pressed, the keyboard service routine detecting that key code will record its state in the status flag (112). The control key bit corresponding to the control key (113) of the status flag (112) is set to 1. When the control key (113) is released, the keyboard service routine that received the key code sets the control key bit to 0. Similarly, for the shift key, the key status flag (
The state is recorded by the shift key bit in 112).

The system switches the speed of the CPtJ (108) when the control key (113) and the shift key (114) are pressed at the same time and the H key (108) is pressed.
115) is pressed to select high speed, said control key (113) and said shift key (114)
Suppose that it is defined that when the S key (l l 6) is pressed at the same time, the low speed is selected.

The keyboard service routine checks whether the input key is the H key (115) or the S key (116), and if it is one of these keys, the control key bit and shift key bit in the key status flag (112) are set. Check that they are both 1, and if they are both 1, if the H key (115) is input, the CP
U is set to high speed, and if the S key (116) is input, the CPU is set to low speed.

In conventional portable computers, the system was controlled from the keyboard in the manner described above.

[Problems to be Solved by the Invention J] However, the above-mentioned prior art has the following problems.

In a computer system, if a combination of key human forces defined to control the system is also defined to achieve a certain function in an application running on that computer system, the user may be able to control the system. If you input that key combination manually, the functions defined in the application may be activated, or conversely, the system may be controlled even if you input it while trying to use the application's functions.

That is, there is a possibility that an expected function may not work or a function other than the expected function may occur. In the worst case, such a problem may cause a fatal flaw to the system, such as data destruction.

The present invention is intended to solve these problems, and its purpose is to provide a keyboard control device that does not conflict with normal manual input when controlling a system using keyboard input. It is about providing.

[Means for Solving the Problems] The present invention provides a portable computer having electronic devices such as a CPU, a memory, an input/output device, an external storage device, a display device, a keyboard, a power supply device, etc., wherein the keyboard has a plurality of general key switches. and a keyboard switch consisting of a plurality of key switches constituted by at least one special key switch, and a keyboard switch connected to the keyboard switch, detects on/off of the key switch, and notifies the CPU of the state of the key switch. , ROM,
It consists of a one-chip microcomputer consisting of RAM, I/O, and a CPU core, and when the general key switch of the keyboard switch is pressed or released, the general key code transmitting means for sending a key code corresponding to a general key switch to the CPU; and an I/O port of the one-chip microcomputer when the special key switch of the keyboard switch is pressed or released; 110 of the l-chip microcomputer when the general key switch is pressed or released while the special key switch of the keyboard switch is pressed; It is characterized by comprising: special general key status transmission means for turning on and off ports;

[Function J] How the keyboard control device of the present invention operates will be explained with reference to FIG.

In FIG. 1, 1 is a keyboard switch, 2 is a special key, 3 is a general key, 4 is an l-chip microcomputer, 5 is a general key code transmitting means, 6 is a special key state transmitting means, and 7 is a special general key state transmitting means. , 15 is a CPU. For convenience of explanation, a normal state and a special state will be introduced and explained as the states of the keyboard.The normal state is a state in which the special key (2) is not pressed. The special state is a state in which the special key (2) is pressed.0 In the normal state, when the general key (3) of the keyboard switch (1) is pressed, the key code is transmitted as the general key code. The signal is sent by the means (5) to the I10 port l of the l-chip microcomputer (4), and further received by the CPU (15). Further, when a certain key is released, the key code is sent to the CPtJ (15) in the same manner as described above.0 When the special key (2) is pressed in the normal state, the state of the keyboard becomes a special state. In the special state, the special key (2) is transmitted by the special key state transmitting means (6).
) is pressed, is notified to the CPU (15) through the I10 port 2 of the L-chip microcomputer (4). Furthermore, when another key is pressed in this state, the special key code assigned to that key by the special general key state transmitting means (6) is transmitted to the I chip microcomputer (4).
/O port 3 to the CPU (15).

[Example] One embodiment of the present invention will be described with reference to FIG.

In FIG. 2, l is a keyboard allocation input, 2 is a special key, 3 is a general key, 4 is an l chip microcomputer, 5 is a general key code transmitting means, 6 is a special key status transmitting means, and 7
is a special general key status transmission means, 8 is I10 port 1.9
is I/O port 2.10 is I/O port 3.11 is data latch l, 12 is data latch 2.13 is data latch 3.14 is system path, 15 is CPU, 16 is RA
M, 17 is a ROM, 18 is a CPU speed selection device, and 19 is a display selection device.

State where the special key (6) is not pressed (normal state)
The manner of input using the keyboard switch (1) will be described below.

When the general key (3) of the keyboard switch (1) is pressed, the key code corresponding to the general key (3) is sent to one of the l-chip microcontrollers (4) by the general key code transmitting means (5). (8)
and its contents are held by the data latch 1 (11). When the key code is output to the data latch 1 (11), a keyboard interrupt is generated to the CPU (15). Said ROM (17
), a routine is activated to read the key code from the data latch 1 (11) and store it in the RAM (t6). The key code stored in the RAM (16) is read out by the keyboard service routine number and passed to the application program to complete the keyboard input.

Next, the state of input using the keyboard switch (1) when the special key (2) is pressed (special state) will be explained. When the special key (2) is pressed, one of the I/O ports 2 (9) of the l-chip microcomputer (4) is turned on by the special key status transmitting means (6).

This information is sent to the data latch 2 (12). While the special key (2) continues to be pressed, the I/O port 2 (9) remains on, and the previous Igc ICPU (1
5), when the data latch 2 (12) is read, it is found that the special key (2) is pressed. Furthermore, when one of the general keys (3) is pressed in a special state, the special key code corresponding to the general key (3) is transmitted to the l-chip microcomputer (4) by the special general key state transmitting means (7). It is output to one of the I/O ports 3 (10). This information is sent to the data latch 3 (13). The states of the data latch 2 (12) and the data latch 3 (13) are monitored at certain intervals by a special key monitoring program stored in the ROM (17). It can be seen that the general key (3) was input in the special state. In this case, if the defined special key code is input, the system will be controlled accordingly.
The CPU (1) is controlled by the PU speed selection device (18).
5) by changing the clock for the display selection device (
19), processing such as switching the display device is performed.

FIG. 3 shows another embodiment of the invention. In Figure 3,
l is the keyboard switch, 2 is the special key, 3 is the general key,
4 is an l-chip microcomputer, 5 is a general key code transmission means,
6 is special key status transmitting means, 7 is special general key status transmitting means, 8 is I/O port 1.9 is I/O port 2, IO
is I/O port 3.11 is data latch 1.14 is system bus, 15 is CPU, 16 is RAM% 17 is ROM
18 is a CPU speed selection device, 19 is a display selection device, and 20 is a system control device.

State where the special key (6) is not pressed (normal state)
The manner of input using the keyboard switch (1) will be described below. When the general key (3) of the keyboard switch (1) is pressed, the key code corresponding to the general key (3) is sent to one of the l-chip microcontrollers (4) by the general key code transmitting means (5). The above I
10 port 1 (8), and the data latch 1 (
11), its contents are retained. When the key code is output to the day clutch 1 (11), the CP
A keyboard interrupt occurs for U(15). A keyboard interrupt service routine for the keyboard interrupt stored in the ROM (17) is activated, reads the key code from the data latch 1 (11), and stores it in the RAM (16). The RAM
The key code stored in (16) is read by the keyboard service routine and passed to the application program, thereby completing the keyboard input.

Next, the state of input using the keyboard switch (1) when the special key (2) is pressed (special state) will be explained. When the special key (2) is pressed, a pulse is generated to one of the I/O ports 2 (9) of the l-chip microcomputer (4) by the special key status transmitting means (6). This pulse is applied to the system controller (2).
0). The system control device (20) reads the data outputted to one of the I/O ports 3 (10) of the l-chip microcomputer (4) by inputting the pulses, and furthermore, in a special state, the general key (3)
) is pressed, the special general key status transmitting means (
7), the special key code corresponding to the general key (3) is assigned to one of the I/Os of the l-chip microcomputer (4).
The zero output to port 3 (10) is then transmitted to the l-chip microcomputer (4) by the special key status transmitting means (6).
A pulse is generated at one said I/O port 2 (9) of the . This pulse is sent to the system control device (20), and the system control device (20) controls one of the I10 port (10) of the l chip migration (4) depending on the input of the pulse. The system control device (20) reads the output data, analyzes the read data, and controls the system accordingly.For example, it sends a signal to the CPU speed selection device (18). Processes such as changing the clock for the CPU (15) and sending a signal to the display selection device (19) to switch the display device are performed.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to control the system by inputting from the keyboard without affecting the conventional interface between the keyboard and the system.

Therefore, the system can be controlled without affecting applications running on the computer.

Also, changing the keyboard switch for that purpose requires adding at least one special key and controlling the keyboard.
This can be done by simply changing the chip microcontroller, and there is no particular cost increase compared to the conventional method using switches. However, considering the increase in the number of portable convenience stores in the future, the effect will be enormous, as it will greatly contribute to miniaturization and improved usability.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the operation of the present invention, FIG. 2 is a diagram showing one embodiment of the present invention, and FIG. 3 is a diagram showing another embodiment of the present invention, FIG. 4 is a diagram illustrating an example of changing the CPU speed by conventional keyboard input.・Keyboard switch ・Special key ・General key ・L chip microcomputer ・General key code transmitting means ・Special key status transmitting means ・Special general key status transmitting means ・I/O port I10 port 2 10 ・ 1 l ・ l 2 ・ l 3・ l 4 ・ l 5 ・ 16 ・ 17 ・ l 8 ・ l 9 ・ 20 ・ 101 ・ 102 ・ 103 ・ 104 ・ 105 ・ 106 ・ 107 ・ 108 ・ 109 ・ ・I/O port 3 ・Data latch 2 Data latch 2・Data latch 3 ・System bus ・CPU ・RAM ・ROM ・CPU speed selection device ・Display selection device ・System control device ・Keyboard switch ・l chip microcomputer ・Scan line ・Lead line ・Data buffer ・Status buffer ・System bus ・CPLI・RAM 110 ・ 111 ・ 112 ・ 113 ・ 114 ・ 115 ・ 116 ・ ・Key buffer ・Key buffer pointer ・Key status flag ・Control key ・Shift key ・H key ・S key

Claims (1)

[Claims] A portable computer having electronic devices such as a CPU, a memory, an input/output device, an external storage device, a display device, a keyboard, a power supply device, etc., wherein the keyboard includes a plurality of general key switches and at least one special key switch. A keyboard switch consisting of a plurality of key switches configured by a key switch, and a ROM, RAM, and I /O, CPU
and a 1-chip microcomputer consisting of a core, and when the general key switch of the keyboard switch is pressed or released, the key corresponding to the general key switch is transmitted through the I/O port of the 1-chip microcomputer. a general key code transmission means for sending a code to the CPU; and a special key code transmitting means for turning on and off the I/O port of the one-chip microcomputer when the special key switch of the keyboard switch is pressed or released. a key state transmitting means; when the general key switch is pressed or released while the special key switch of the key port switch is pressed, turning on the I/O port of the one-chip microcomputer; - A keyboard control device comprising: special general key state transmitting means that turns off;