JPH01226018A - Input device - Google Patents

Abstract

PURPOSE:To attain display with high responseness by changing waiting time following one software scanning of a row direction line correspondingly to the longest chattering time out of chattering periods inherent in respective key switches on a keyboard in accordance with the kind of a keyboard to be used. CONSTITUTION:In case of the 1st keyboard having the longest chattering time ta, a queuing time setting switch 8 in a time data setting means 6 is switched to the queuing time ta' side by external operation. A buffer 12 responds to the switching output of the switch 8 and reads out the data of queuing time ta' corresponding to the switching output from a table 10. At the time of reading the data of the queuing time ta', the buffer 12 outputs the data of the queuing time ta' to a key switch operation detecting means 4. The means 4 executes operation for adding one software scanning time t2 of the row direction to the data of the queuing time ta' outputted from the buffer 12.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides a method for electrically connecting a plurality of key switches, which open and close between two opposing contacts when pressed down, in a row direction and a column direction, respectively. A keyboard arranged in a matrix and each contact on the electrically row side of each of the key switches are sequentially scanned row by row at a predetermined potential, and the electrical power of each key switch is Specifically, changes in the potential of each contact in the column direction are detected by software scanning sequentially for each corresponding column every one software scan period in the row direction, and the operation of a specific key switch is detected. The present invention relates to an input device including a key switch operation detection means.

(Prior Art) FIG. 3 is a configuration diagram of a keyboard and key switch operation detection means included in the input device. In FIG. 3, reference numeral 2 is a keyboard, and this keyboard 2 is
A plurality of key switches 5xy (x=1...
2. . . . -, m, y=1.2° . . . , n) are electrically arranged in a matrix. Each key switch Sxy is configured such that two opposing contacts open and close when pressed down. Row direction lines xi, x2 . in electrical relationship.・
. . , X-curvature is a column direction line yt in the same electrical relationship with one contact point of each key switch Sxy.

Y2. . . , yn are similarly individually connected to the other contact of each key switch Sxy. Reference numeral 4 denotes a key switch operation detection means composed of a microcomputer, and this key switch operation detection means 4 detects the row direction lines xi, x2 in each key switch Sxy.
．． . . , each contact on the xat side is sequentially software-scanned row by row at a predetermined potential, and the column direction lines y1 . y2. ..., changes in the potential of each contact on the yn side for each column (every 1 software scan cycle in the row direction)
The operation of a specific key switch is detected by sequential software scanning.

(Problem to be Solved by the Invention) By the way, in the input device having such a configuration, the contacts of each key switch Sxy close when pressed down at time to, as shown in FIG. Te (ON)
Due to the so-called chattering phenomenon, when the contact potential changes from high level to low level, and when the contact potential changes from low level to high level after being opened (0FF) by releasing the push-down operation at time tl,
The potential changes alternately between a high level and a low level over a predetermined time (chattering time) at the ON time to and the OFF time table 1, respectively.

It is well known that such a chattering phenomenon is a very inconvenient phenomenon when specifying the operation of a particular key switch Sxy based on a change in the contact potential.

Therefore, in order to prevent erroneous recognition of the operation of the key switch Sxy due to such chattering phenomenon, conventionally,
Time exceeding the longest chattering time among the unique chattering times of each key switch Sxy (column direction line yt).

y2. . . . after the total time obtained by adding the waiting time to the time required for one software scan of yn), the key switch operation detection means 4 detects the specific key switch Sxy that has been operated.

However, in the past, for such detection, the above waiting time was uniformly set to be long regardless of the type of keyboard, taking into consideration that the chattering time differs for each key switch Sxy. As a result, it becomes necessary to set the key switch S for a long time.
There is a problem in that the time from when the key switch Sxy is operated to when the CRT or the like displays a display corresponding to the operation is extremely long, resulting in extremely low responsiveness.

The present invention has been made in view of the above problems, and includes:
Depending on the type of keyboard used, it is possible to change the waiting time after one software scan of the column direction line according to the longest chattering time among the chattering times unique to each key switch of that keyboard, and the waiting time after one software scan of the column direction line can be changed. The purpose is to greatly improve the responsiveness of display on a CRT.

(Means for Solving the Problems) In order to achieve such an object, the present invention provides a method in which a plurality of key switches, which open and close between two opposing contacts when pressed down, are electrically connected in the row direction. The keyboard is arranged in a matrix in the column direction, and each of the contacts on the row direction side of each of the key switches is sequentially scanned by software for each row at a predetermined potential. Electrically, changes in the potential of each contact on the column direction side of each switch are detected by software scanning sequentially for each column corresponding to l software scan period in the row direction, and the changes in the potential of each contact on the electrically column side are detected and The total time obtained by adding the wait time to the key switch operation detection means that detects the operation and the time required for one software scan in the column direction is the longest among the chattering times unique to each key switch in the column direction. and time data setting means for setting and outputting the waiting time in a switchable manner so that the waiting time exceeds the chattering time of is calculated, and the operation of a specific key switch is detected after the total time has elapsed according to the calculation result.

(Function) Any key switch on the keyboard (specific key switch)
When pressed down, the two opposing contacts of the specific key switch are closed. Then, the software sequentially scans each contact on each key switch that is electrically on the row direction line side at a predetermined potential row by row, and the electrical contacts on each key switch that are on the column direction line The key switch operation detection means sequentially scans changes in the potential of the contacts column by column by software, and detects the specific key by changing the potential of the contact corresponding to the specific key switch during the software scan of the column direction line. Detects switch operations.

In this case, the key switch operation detection means performs a calculation of adding up the waiting time given by the time data setting means to one software scan time in the column direction, and after the total time corresponding to the calculation result has elapsed, the key switch operation detection means Perform switch detection. The above waiting time is externally switched and set so that this total time exceeds the longest chattering time among the unique chattering times of each key switch in the column direction. The operation detection means can detect a specific key switch in the shortest time corresponding to the type of keyboard, and as a result, an input device with excellent responsiveness can be obtained.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of an input device according to an embodiment of the present invention. In FIG. 1, reference numeral 2 denotes a keyboard in which a plurality of key switches that open and close between two opposing contacts when pressed are arranged in a matrix in an electrical relationship in the row and column directions. It is. Since the structure of this keyboard 2 is similar to that shown in FIG. 3, detailed explanation of its structure will be omitted. 4 electrically scans each contact on each key switch that is electrically on the line side in the row direction at a predetermined potential by software sequentially for each row, and electrically on each key switch on the line side in the column direction. A key switch operation detection means that detects the operation of a specific key switch by sequentially software scanning the changes in the potential of each contact in each column (every one software scan period in the row direction). be. Since the configuration of this key switch operation detection means 4 is similar to that shown in FIG. 3, a detailed explanation of the configuration will be omitted.

The input device of the present embodiment has a time data setting means 6 which provides waiting time data to the key switch operation detecting means 4, and the time data setting means 6 sets the waiting time according to the type of keyboard. A waiting time setting switch 8 such as a dip switch whose switching state is set externally, a table 10 in which waiting time data is written, and a table 10 corresponding to the switching state of the waiting time setting switch 8. A buffer 12 reads waiting time data written in the buffer 12 and outputs the read waiting time data to the key switch operation detection means 4.
It is characterized by consisting of.

Next, the operation will be explained with reference to FIG. First, let t2 be the time required for one software scan of the column direction lines yt, y2, . . . , yn for each key switch of the keyboard 2 by the key switch operation detection means 4. This software scan time t2 is a fixed value determined by the key switch operation detection means 4 regardless of the type of keyboard 2.

In this example, it is assumed that the longest chattering times for each key switch in the column direction on three types of keyboards are ta, tb, and tc.

First, the case of the first keyboard in which the longest chattering time is ta will be described. Time data setting means 6
Externally operate the waiting time setting switch 8 to set the waiting time ta.
'Switch to side. The buffer 12 responds to the switching output of the waiting time setting switch 8 and reads data of the waiting time ta' corresponding to the switching output from the table IO. When the buffer 12 reads the data of the waiting time ta', it outputs the data of the waiting time ta' to the key switch operation detection means 4. The key switch operation detection means 4 executes an operation of adding one software scan time t2 in the column direction to the data of the waiting time ta' from the buffer 12. The total time based on this calculation is (t2+
ta').

Next, when the software scan in the column direction is completed, the key switch operation detection means 4 detects the key switch operation after the above-mentioned waiting time ta' has elapsed.

Similarly, the second case where the longest chattering time is tb
In the case of the keyboard, the waiting time setting switch 8 of the time data setting means 6 is externally operated to switch to the side where the waiting time becomes tb'. Then, buffer! 2 is the waiting time t corresponding to the output from the waiting time setting switch 8.
By reading b' from the table IO, the key switch operation detection means 4 detects the key switch after the waiting time tb' has elapsed after the end of the software scan in the column direction in the same manner as described above. Similarly, for the third keyboard with the longest chattering time tc, the key switch operation detecting means 4 detects the key switch after the waiting time tc' has elapsed after the end of the software scan in the column direction.

Therefore, according to this embodiment, by externally changing the setting of the waiting time setting switch 8 according to the type of keyboard used, key switch operation can be detected in the shortest corresponding time. According to the type of keyboard, operation input of each key switch can be processed with high responsiveness.

(Effects) As is clear from the above explanation, according to the present invention,
Depending on the type of keyboard used, the waiting time after one software scan of the column direction line can be changed according to the longest chattering time among the chattering times unique to each key switch of that keyboard. Display operations on a CRT, etc. can be performed with high responsiveness in accordance with operational inputs.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an input device according to an embodiment of the present invention, FIG. FIG. 3 is a configuration diagram of the keyboard and key switch operation detection means, and FIG. 4 is a diagram for explaining the chattering phenomenon. 2...Keyboard, 4...Key switch operation detection means, 6...Time data setting means, 8...Waiting time setting switch, IO...Table, 12...Buffer.

Claims (2)

[Claims] (1) A keyboard in which a plurality of key switches whose two opposing contacts open and close when pressed are electrically arranged in a matrix in the row direction and the column direction, and each of the key switches. The software scans each contact electrically on the row side in each row at a predetermined potential at a predetermined potential, and also changes the potential of each contact electrically on the column direction in each key switch. a key switch operation detection means for detecting the operation of a specific key switch by sequentially software scanning each column corresponding to one software scan period in the row direction; and one software scan in the column direction. Time data to be set and output so that the waiting time can be changed so that the total time obtained by adding the waiting time to the time required for the key switch in the column direction exceeds the longest chattering time among the chattering times unique to each key switch in the column direction. setting means, the key switch operation detection means calculates the total time based on the waiting time given from the time data setting means, and after the total time according to the calculation result has elapsed, the key switch operation detection means detects the operation of a specific key switch. An input device characterized by detecting an operation. (2) The time data setting means includes a waiting time setting switch whose switching state is externally set in accordance with a waiting time depending on the type of keyboard, a table in which waiting time data is written, and the waiting time. 2. A buffer according to claim 1, further comprising a buffer for reading waiting time data written in said table in response to a switching state of a setting switch, and outputting the read waiting time data to said key switch operation detection means. input device.