JPH0518130B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a keyboard that is widely used as an input device for information processing devices.

[Conventional technology]

Keyboards conventionally used in information processing devices are
A key matrix in which a plurality of character keys and a plurality of function keys are arranged in a matrix; a scan signal is sent to the key matrix; a control circuit that inputs a scan response signal indicating the position of a pressed key, and sends out a character code or function code corresponding to the pressed character key or function key; It has an interface circuit that inputs a character code or function key code and sends it as an information signal to an external information processing device. Character keys are keys for inputting character codes corresponding to letters, numbers, etc. to an external information processing device as information signals, and function keys are keys for controlling the operation of an external information processing device. This key is used to input the code to an external information processing device as an information signal. When a keyboard is used, letter keys are pressed more frequently compared to function keys;
There is also a function key that has the function of canceling the input of a character code, and by pressing this key, even if a character key is pressed by mistake, it can be canceled relatively easily. On the other hand, once a function key is pressed, an external information processing device often starts operating based on the information corresponding to the function code. takes a lot of time.

To prevent erroneous inputs caused by pressing the wrong function key, conventional keyboards either separate the function key from the character keys and place it in a position that is difficult to press, or adjust the pressing force of the function key to the character key. This was prevented by making it harder to press by making it heavier than the pressing force.

[Problem that the invention seeks to solve]

However, with conventional methods, the number of types of keys increases due to restrictions on key placement and the use of keys with different pressing forces, which makes standardization of keys difficult and increases the manufacturing cost of keyboards. There is. Furthermore, if an external information processing device is provided with a function to prevent mistakenly pressing a function key, there are problems such as narrowing the user's program area in the memory of the external information processing device and limiting its performance.

SUMMARY OF THE INVENTION An object of the present invention is to provide a keyboard that can easily and accurately prevent erroneous inputs caused by pressing a function key by mistake.

[Means for solving problems]

The keyboard according to the present invention turns on/off a plurality of row-direction wires, a plurality of column-direction wires, and a part of the intersection between the row-direction wires and the column-direction wires, and information about the intersection with a single press. a key matrix having a first group of keys for transmitting a signal and a second group of keys for turning on and off another part of the intersection and permitting transmission of the information signal of the intersection when pressed again; , a first means for scanning by sequentially applying a predetermined level to the column direction wiring; and a first means for scanning by sequentially applying a predetermined level to the column direction wiring; a second means for confirming that the
a third means for confirming that one key in the second key group has been recovered after the first predetermined period of time has passed since the key in the first key group has been recovered; , fourth means for outputting only the information signal corresponding to the key confirmed to have been pressed by the second means to an external information processing device; and one key in the second key group. the key whose depression was confirmed by the second means is restored;
Only when the second means confirms that the same key has been pressed within a second predetermined period of time after the recovery of the key is confirmed by the third means. The present invention is characterized by comprising a fifth means for sending an information signal corresponding to the key to an external information processing device.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the keyboard of the present invention, and FIGS.
3 is a flowchart showing the operation of the keyboard shown in FIG. In FIG. 1, a key matrix 7 includes four character keys 4A, 4B, 4C, and 4D and two function keys 4E and 4F arranged in a matrix. Character keys 4A, 4B and character key 4 located at the intersection of the matrix in each column in the vertical direction
The fixed contacts of C and 4D are each drive circuit 2A.
The fixed contacts of the function keys 4E and 4F are connected to the output end of the drive circuit 2C. The movable contacts of the character keys and function keys located at the intersections of the matrix in each row in the horizontal direction are pull-up resistors of 3A, one end of which is connected to the pull-up power supply 11 (+5V).
3B and the input port 1D of the control circuit 1,
Connected to 1E. Drive circuit 2A, 2B, 2
The input terminal of C is the output port 1 of each control circuit 1.
Connected to A, 1B, and 1C.

Next, the operation of the keyboard shown in FIG. 1 will be explained. First, to explain the operation of the control circuit 1 to determine which key position on the keyboard has been pressed, the control circuit 1 uses the output port 1A to check which key in the key matrix 7 has been pressed. , 1B, 1C to drive circuits 2A, 2
High level scan signals are sequentially sent to the input terminals of B and 2C. Drive circuit 2A, 2B, 2C
inputs the high-level scan signal sent from the control circuit 1, converts it to a low-level scan signal, and connects each row of keys of the key matrix 7 from the output end to the fixed contacts to output this low-level scan signal. Sends a scan signal. The fixed contact of the pressed character key or function key is turned on by the movable contact, and when a scan signal is sent to a row of the pressed key, input port 1 is turned on.
If either D or 1E is set to low level and no key is pressed, it will be kept at high level even when an information signal is sent to the fixed contact of the key in any column of input port 1D or 1E. It will be done. That is, the input ports 1D and 1E correspond to the scan signals sequentially sent from the control circuit 1, and when there is a pressed key in the key matrix 7, the input port (1D or 1E) of the row to which the key belongs )
A scan response signal is sent, which causes the signal to go low. The control circuit 1 inputs this scan response signal, detects the terminal number of the input port, and uses the combination of the terminal number of the input port and the terminal number of the output port set to high level to create the key matrix 7.
It is determined which key constituting the key has been pressed, and the character code corresponding to the pressed character key or the function code corresponding to the pressed function key is sent to the interface circuit 5. The interface circuit 5 sends the input code as an information signal to an external information processing device.

Next, the operation when using the keyboard shown in FIG. 1 will be described in detail using a flowchart. When the keyboard is powered on and becomes operational, a scan signal is sent to the fixed contacts of the character keys 4A and 4B of the key matrix 7 via the drive circuit 2A in step 21 of FIG.
Move to step 22, press character key 4A, character key 4B
It is determined whether any of the buttons are pressed. If neither the character key 4A nor the character key 4B is pressed, the process moves to step 24, and a scan signal is sent to the fixed contacts of the character key 4C and the character key 4D of the key matrix 7 via the drive circuit 2B. Then, the process moves to step 25, where it is determined whether either the character key 4C or the character key 4D is pressed. If neither the character key 4C nor the character key 4D is pressed, the process moves to step 27, where a scan signal is sent to the fixed contacts of the function key 4E and the function key 4F of the key matrix 7 via the drive circuit 2C, and the process proceeds to step 27. 28, it is determined whether either the function key 4E or the function key 4F is pressed. Faxion key 4E, Faxion key 4
If none of F is pressed, go to step 21 again.
If no key in the key matrix 7 has been pressed, the process moves from step 21 to step 28 and waits for any key to be pressed. When either character key 4A or character key 4B of key matrix 7 is pressed, the step
At step 22, it is determined that either the character key 4A or the character key 4B has been pressed, and the process moves to step 23, where the character code corresponding to the pressed key is stored in the memory (not shown) of the control circuit 1. , proceed to step 30 in FIG. Even if the contact turns on when a character key is pressed, the contact breaks momentarily due to collision vibration. Since the time during which this instantaneous interruption occurs is approximately 1/100th of a second or less, in order to prevent malfunctions due to instantaneous interruption of this contact, in step 30, a predetermined time t ₁ (here, 1/100th of a second) is set.
After the time has elapsed, go to step 31 and then step 23 again.
It is determined whether or not the character key corresponding to the character code stored in is pressed. If the same character key is pressed, the process moves to step 32, and the character code corresponding to the pressed character key is stored in the interface. Send to the ace circuit. At step 31, if the character key corresponding to the character code stored at step 23 is not pressed, the process returns to the first step 21 (Figure 2).
, and waits for any key in key matrix 7 to be pressed. When either the character key 4C or the character key 4D of the key matrix 7 is pressed, the process moves to step 24, and the scan signal is sent to the fixed contact of the character key 4C or the character key 4D of the key matrix 7 to the drive circuit. 2B, and the process moves to step 25. At step 25,
It is determined that either the character key 4C or the character key 4D has been pressed, and the process moves to step 26, where the character code corresponding to that character key is stored in the memory (not shown) of the control circuit 1, and as shown in FIG. step 30
Move to. In order to prevent malfunctions due to instantaneous interruption when a character key is pressed in step 30 and its contact is turned on, after a predetermined time _t1 has elapsed, the process moves to step 31, and in step 26 the character key corresponding to the stored character code is pressed. It is determined whether or not the same character key is pressed. If the same character key is pressed, the process moves to step 32, and in step 32, the character code corresponding to the pressed character key is sent to the interface circuit 5. be done. If the same character key as the character key corresponding to the character code stored in step 26 is not pressed in step 31, the process returns to step 21 (Figure 2) and any key in key matrix 7 is pressed. I'm waiting for you. At step 32, press letter key 4
When the character code corresponding to the pressed character key of A, 4B, 4C, or 4D is sent to the interface circuit 5, the process moves to step 33, and the character code stored in step 23 or step 26 is sent to the interface circuit 5. It is determined whether the same character key corresponding to the character key has been restored (the corresponding input port 1D or input port 1E is at a high level), and if the character key has not been restored, the loop path returning to step 33 is followed. Wait for this key to be restored. When this character key is restored, the process moves to step 34, and after a predetermined time _t1 has elapsed to prevent malfunctions due to instantaneous disconnection of the contacts of this character key, the process moves to step 35, where it is checked again whether or not this character key has been restored. is determined,
If not recovered, proceed from step 35 to step 34.
It loops back to and waits for this key to be restored. If this key is restored, it is determined that the key has been restored in step 35, and the process returns to the first step 21.
It is waiting for any key in the key matrix 7 to be pressed.

Key matrix 7 function key 4E
Alternatively, if one of the function keys 4F is pressed, function keys 4E and 4F are pressed in step 27.
A scan signal is sent out, and in step 28 it is determined that either function key 4E or 4F has been pressed, and the process moves to step 29, where the character code corresponding to that function key is stored in the memory of control circuit 1 ( (not shown), and the process moves to step 36 in FIG. In step 36, after the required time _t1 has elapsed to prevent malfunctions due to instantaneous disconnection of the contacts of function key 4E or function key 4F, the process moves to step 37, and the function key code stored in step 29 is rewritten. Function key 4E same as corresponding function key
Alternatively, it is determined whether or not the function key 4F is pressed, and if it is not pressed, the process returns to step 21 at the beginning of FIG. When it is confirmed in step 37 that the function key corresponding to the function code stored in step 29 has been pressed, the process moves to step 38 to check whether the same function key has been restored or not. is determined, and if it has not been restored, the process loops back to step 38 and waits for the same function key to be restored. When this function key is restored,
The process moves from step 38 to step 39, and after the required time _t1 has elapsed to prevent malfunctions due to instantaneous disconnection of the contacts of this function key, the process moves to step 40, where it is determined whether or not the same function key has been restored. If the function key has not been restored, the process loops back to step 39 and waits for this function key to be restored. If the same function key is restored at step 40, move to step 41,
A separately arranged timer (not shown) is started. Next, the process moves to step 42, where it is determined whether the time measured by the timer has reached a predetermined time _t2 (for example, 10 seconds), and if the measured time has not reached the required time _t2 , the process moves to step 43. It is determined whether or not the function key is pressed. If it is pressed, the process moves to step 44, and the required time t ₁ is passed to prevent malfunctions due to instantaneous disconnection of the function key contact.
After this has elapsed, the process moves to step 45, where it is determined whether or not the same function key has been pressed. If not, the process loops back to step 42 and waits for this function key to be pressed. If the same function key is pressed in step 45, the process moves to step 46, and the control circuit 1
A function code corresponding to the pressed function key is sent to the interface circuit.
If the same function key is not pressed in step 45, it is determined that the function key was not pressed, and the process returns to step 42. When the timer time reaches the predetermined time _t2 , the process returns to the beginning of FIG. Returning to step 21, the function code corresponding to this function key is not sent to the interface circuit 5. When the function code is sent to the interface circuit 5 in step 46, the process moves to step 47. In step 47, it is determined whether the same function key has been restored, and if not, the process starts again. Going around the loop back to 47, waiting for the same function key to be restored. When the same function key switch is restored, the process moves to step 48, and after a predetermined time _t1 has elapsed to prevent malfunctions due to momentary disconnection of the function key contacts, the process moves to step 49, where it is determined whether the same function key has been restored. If it has not been restored, the process loops back to step 48 and waits for the same function key to be restored. When it is confirmed in step 49 that the function key has been restored, the process returns to the first step 21 in FIG.

FIG. 5 is a block diagram showing a second embodiment of the keyboard of the present invention. In FIG. 5, the key matrix 9 has 16 keys arranged in a matrix, including character keys 8a and function keys 8b. Output port 1 of control circuit 10
A, 1B, 1C, 1D are each drive circuit 2
Connected to the input terminals of A, 2B, 2C, and 2D. The fixed contact terminals of the keys at the intersections of the matrices in each row in the vertical direction are commonly connected to each drive circuit 2A,
The movable contacts connected to the output terminals 2B, 2C, and 2D at the intersections of each row of horizontal matrices are as follows:
Pull-up resistors 3A, 3B, 3C, 3 commonly connected to each pull-up power supply 11 (+5V)
D, and these movable contacts are connected to the input ports 1E, 1F, 1 of the control circuit 10, respectively.
Connected to G and 1H. Drive circuit 2A, 2
The input terminals of B, 2C, and 2D are each connected to control circuit 1.
0 output ports 1A, 1B, 1C, and 1D.

The keyboard in FIG. 5 differs from the keyboard in FIG. 1 in that the keys connected to the drive circuit 2C and arranged in a vertical line are only function keys 4E and 4F. Circuit 1 simplifies the circuit that determines that the pressed key is a function key, but
In the keyboard of FIG. 8, the keys arranged in a vertical line in the key matrix 9 are function keys, numeric keys, and other character keys, and the control circuit 10 has the following functions:
Memorize in advance the position of the function key in the key matrix as a combination of the input port number that sends out the high-level scan signal and the number of the output port that inputs the low-level scan response signal, and then press the key. The keyboard in Figure 2 compares the position of the pressed key to determine whether the pressed key is a function key or not, and processes the code of the pressed key in exactly the same way as the keyboard in Figure 1. As shown in the flowchart from step 28 onwards, the function key and other keys are distinguished. Therefore, its function as a key matrix is exactly the same as that of the keyboard shown in FIG.
That is, with the keyboards shown in FIGS. 1 and 5, if you press the function key once and realize that you have pressed it incorrectly when inputting the information signal corresponding to the function key to an external information processing device, If the same function key is not pressed again within the predetermined time _t2 , the control circuit 10 will
The program proceeds to step 21 without proceeding from step 45 to step 46 in FIG. 4, and the function code of the function key is not sent to the interface circuit 5, making it easy to input incorrectly due to pressing the wrong function key. can be prevented.

〔Effect of the invention〕

As explained above, the keyboard of the present invention prevents the information signal corresponding to the function key from being input to the information processing device unless the function key is pressed once to recover and then pressed again within a predetermined time. This makes it extremely easy to implement functions without increasing manufacturing costs by placing restrictions on key layouts or making it difficult to standardize keys, and without restricting the performance of external information processing devices. This has the effect of preventing erroneous key input.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the keyboard of the present invention, FIGS. 2, 3, and 4 are flowcharts showing the operation of the keyboard of FIG. 1, and FIG. 5 is a block diagram showing an embodiment of the keyboard of the present invention. FIG. 3 is a block diagram showing a second embodiment. 1, 10...control circuit, 1A, 1B, 1C, 1
D...Output port, 1D, 1E, 1F, 1G, 1
H...Input port, 2A, 2B, 2C, 2D...
Drive circuit, 3A, 3B, 3C, 3D...Pull-up resistor, 4A, 4B, 4C, 4D, 8a...
Character keys, 4E, 4F, 8b...Function key, 5...Interface circuit, 7, 9...Key matrix, 11...Pull-up power supply.

Claims (1)

[Claims] 1 Multiple row-direction wiring, multiple column-direction wiring,
A first key group for turning on and off a part of the intersection between the row-direction wiring and the column-direction wiring and transmitting an information signal at the intersection with a single press, and turning on and off another part of the intersection. a key matrix having a second key group for permitting transmission of an information signal at an intersection point when pressed again; a first means for scanning by sequentially applying a predetermined level to the column direction wiring; a second means for confirming that one key in the first and second key groups is pressed a first predetermined time after the key is pressed; and a second means for confirming that one key in the first and second key groups is pressed. third means for confirming that one of the keys has been recovered after the first predetermined time period has elapsed since the key has been recovered;
fourth means for outputting only information signals corresponding to keys confirmed to have been pressed by the second means among the keys in the first key group to an external information processing device; A point in time when the key whose pressing of one key in the second key group is confirmed by the second means is restored, and the recovery of the key is confirmed by the third means. and a fifth means for transmitting an information signal corresponding to the key to an external information processing device only when the second means confirms that the same key has been pressed within a second predetermined time period. A keyboard comprising: means.