JPH04293113A - Key scan method and keyboard device - Google Patents

Abstract

PURPOSE:To prevent the deterioration of a key scan function even in the case plural input devices are connected by detecting the input device by reading a scan input, and executing a scan at every line with regard to its input device. CONSTITUTION:With regard to plural input devices 1, 2,...(n)-1, and (n) for constituting a key matrix, all scan outputs become active successively at every input device by a keyboard control controller, and by reading a scan input in this case, the inputted input device is detected, and with regard to its input device, a scan is executed at every line. That is, before scanning at every line each deuce of the input devices 1, 2,...(n)-1, and (n) for constituting the key matrix, all the key outputs become an active state at every device, and by confirming a key input in such a state, whether the input exists or not is confirmed. Accordingly, since a key scan is executed with regard to a keyboard unit whose key is depressed, the key is detected quickly.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key scanning method and keyboard device, and more particularly to a method and device for scanning key inputs from a plurality of input devices.

0002

2. Description of the Related Art Input devices such as keyboards and touch panels are generally connected to information processing devices such as computers and word processors, and input is performed by operating these devices by an operator. For example, when detecting a key press on a keyboard unit with such an input device, one line of one port (key scan output port) making up the key matrix is activated (activated) in turn.
By setting the input port to "L" and reading the other port (key scan input port), it is possible to know whether at least one line of the input ports is active ("L").

FIG. 7 shows a typical connection example of a key matrix in which key scanning is performed. The key scan output port is normally inactive (“H”). Even if the key switch is pressed in this state, the key scan input port remains inactive (“H”). Also, only one line (for example, A0) of the key scan output port is active (
“L”) and on this line (key switch 09, 12
, 08, 10, 11, 14, 15, 13) and the key scan input port is read, only the line at the position of that key switch becomes active (“L”). For example, when key switch 08 is pressed, only line B2 becomes active (“L”).
) and other input ports are inactive (“H”). The above operations are performed by the controller, and the positions of the pressed keys are detected while being repeated in sequence.

[0004] Incidentally, there are cases in which a plurality of keyboard units and the like are combined to form one input device, which is connected to an information processing device. In such a configuration, key scanning is performed sequentially on each keyboard unit in a certain order. That is, when the key scan operation for each line for one input device is completed once, the key scan of the next input device is executed, and after scanning up to the last input device, it returns to the first input device and starts the key scan again. Repeat the action.

[0005]

As described above, in the case of a configuration in which multiple input devices are connected, for example, if all the keyboard units are controlled by one controller,
Depending on the weight of the load, there may be a time lag between when a key is pressed and when it is detected. Furthermore, if multiple keyboard units are pressed almost simultaneously, the key immediately after scanning may not be detected. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a key scanning method and a keyboard device that can prevent the key scanning function from deteriorating even when a plurality of input devices are connected.

[0006]

[Means for Solving the Problem] In the invention as set forth in claim 1, regarding a plurality of input devices constituting a key matrix,
All the scan outputs are activated sequentially for each input device, and the input device is detected by reading the scan input at this time, and each line of the input device is scanned. The invention according to claim 2 provides a plurality of input devices that constitute a key matrix and are provided with scan input and scan output, and activate the scan output for each of the plurality of input devices and activate it for each line. A keyboard device is provided with an output active means and a scan means for reading a scan input corresponding to a scan output activated by the output active means. The invention according to claim 3 includes a plurality of input devices forming a key matrix and having scan inputs and scan outputs, and output activation means for activating all scan outputs of the plurality of input devices and activating them line by line. and scanning means for reading the scan input corresponding to the scan output activated by the output activation means, and an input that has been input while all the scan outputs of the plurality of input devices are activated by the output activation means. The keyboard device is provided with an input order storage means for storing the order of the devices, and a control means for causing the scanning means to read the scan input in the order of the input devices stored in the input order storage means.

[0007]

[Operation] In the present invention, before scanning each line of the input devices forming the key matrix, all key outputs are activated for each device, and key inputs in this state are confirmed. Check to see if there is any input.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 6. FIG. 1 shows the configuration of a keyboard device. The keyboard device includes input devices 1, 2, which are composed of a plurality of keyboard units and touch panels...
, n. Each of these input devices is connected to a bus line 7 of a CPU (central processing unit) of a computer (not shown) via a keyboard controller 6 that controls key scanning. FIG. 2 shows the appearance of an example of the keyboard unit used in this embodiment. This keyboard unit includes an item key section 8 with a touch panel arranged on the surface of a display unit such as an LCD (liquid crystal display), an item key page switching key 9, a function key 10, a control key 11, and an A/N keyboard section. . FIG. 3 shows the structure of the key matrix, and FIG. 4 shows the key arrangement of the keyboard. The numbers assigned to the key matrix in FIG. 3 correspond to the numbers of the keys arranged on the keyboard, respectively.

Next, a key scanning operation by the keyboard device configured as described above will be explained with reference to FIG. It is now assumed that n input devices 1 to n are connected to the keyboard controller. When performing a key scan, set the input device number I to 1 (step 1)
, all lines (A0 to A11) of the key scan output port connected to the set input device I are made active (“L”) at the same time (step 2). At this time,
Reads the key scan input port of input device I (step 3) and determines whether all are “H” (step 4)
).

If any of the read key scan input ports is active (“L”) (step 4;
N), that is, if any key switch in the input device I is pressed, key scan is performed by activating (“L”) the key scan output port of the input device I one line at a time ( Step 5). After the key scan of the input device I is completed, or if all keys are inactive (“H”) in step 4 (N), it is determined whether I is n (step 6).

If I is not equal to n (step 6; N
), that is, if the key scan has not been completed up to the last input device n, in order to perform the key scan for the next input device, replace the input device number I with I+1 (step 7), and proceed from step 2. Repeat step 6. On the other hand, if I is equal to n (Step 6; Y), that is, if the key scan has been performed up to the last input device n, if the end of the key scan is not instructed by pressing the end key, etc. (Step 8; N) Return to step 1 and repeat the key scan from the first input device 1. If termination is instructed (step 8; Y), the process is terminated.

Next, a second embodiment will be explained based on FIG. 6. For ease of explanation, key matrix 1~
Regarding n, a simplified version is shown. In this embodiment, each of the key scan input port signals of each keyboard unit is inverted and the multi-input OR gate 21-1
, ..., 21-n. Each multi-input OR gate 21
The outputs of -1, . . . , 21-n are inverted again and input to an interrupt order determining circuit 22 that determines the interrupt order. This allows the order of the input devices in which the keys were pressed to be accurately determined. In order to quickly detect which part of each keyboard unit is pressed, first,
Activate all scan outputs and read scan inputs.

[0013]

According to the invention as claimed in claims 1 and 2, regarding the keyboard unit in which a key is pressed,
Because the key scan is performed, keys are detected faster. There is an effect. According to the third aspect of the present invention, since the order in which the keys are pressed is detected, it is possible to detect the presses even if keys are repeatedly pressed on the same input device.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a keyboard device of the present invention.

FIG. 2 is an external view of an input device used in the embodiment.

FIG. 3 is a configuration diagram of a key matrix of an input device used in the embodiment.

FIG. 4 is a diagram showing the key arrangement of a keyboard used in the embodiment.

FIG. 5 is a flowchart illustrating key scanning operations according to an embodiment.

FIG. 6 is a schematic configuration diagram showing the configuration of another embodiment.

FIG. 7 is an explanatory diagram illustrating a connection state of a key matrix.

[Explanation of symbols]

1, 2, n-1, n...Input device 6...Keyboard control controller 7...Bus lines 21-1, 21-n...Multi-input OR gate 22...Interrupt order determination circuit

Claims (3)

[Claims] Claim 1: For a plurality of input devices constituting a key matrix, sequentially activate all scan outputs for each input device, read the scan input at this time to detect the input device, and detect the input device. A key scanning method characterized by scanning each line of an input device. 2. A plurality of input devices forming a key matrix and having scan inputs and scan outputs, and output activation means for activating scan output for each of the plurality of input devices and activating it line by line. , and scanning means for reading the scan input corresponding to the scan output activated by the output activation means. 3. A plurality of input devices forming a key matrix and having scan inputs and scan outputs; output activation means for activating all scan outputs of the plurality of input devices and activating them line by line; a scanning means for reading scan inputs corresponding to scan outputs activated by the output activating means; and an order of input devices to which inputs have been made while all scan outputs of the plurality of input devices are active by the output activating means. 1. A keyboard device comprising: input order storage means for storing input order storage means; and control means for causing said scan means to lead scan inputs in the order of input devices stored in said input order storage means.