JPS63266515A - Keyboard - Google Patents

Abstract

PURPOSE:To prevent an output of a key operation data which an operator does not take part in, by providing a key lock circuit in an output signal line of a keyboard, and setting a keyboard output data as a prescribed signal at the time when there is no key operation, when an operation of the keyboard is suspended on the way. CONSTITUTION:When an operator closes a clock switch 143, an output of an inverter 142 becomes '1', and a keyboard output data 15 becomes '1' irrespective of a key data 13. The keyboard output data 15 in this case outputs '1' continuously, and it is a signal corresponding to a state that a key operation is not executed. That is, by closing the clock switch 143, an output of a keyboard matrix by a key operation which an operator does not take part in is obstructed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a keyboard that is a data input device for personal computers, word processors, and the like.

[Conventional technology]

In conventional keyboards, outputs from key operations are transmitted to a data processing device as they are.

[Problem that the invention seeks to solve]

When the keyboard operator leaves his/her seat in the middle of data entry, a key on the keyboard is pressed intentionally or unintentionally by another person, or is physically pressed due to an object falling, etc. Accidents may occur that destroy data. Previously, there were no special measures against such accidents.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a keyboard that does not output key operation data that does not involve the operator.

[Means for solving problems]

In the present invention, a key lock circuit is provided on the output signal line of the keyboard. This key lock circuit includes means for outputting a signal equal to the key operation data that is input thereto, means for outputting a predetermined signal when no key operation is performed, regardless of key operation, and two of these. and means for selectively switching between the respective signals obtained from the two means.

[Effect]

When a keyboard operator leaves his/her seat in the middle of data input, the key lock circuit can be set to output a predetermined output signal when no key is pressed, and the key lock circuit can be set to output a predetermined output signal when no key is pressed. Even if there is a key operation,
Since the output from the keyboard is a specified output signal when no key is operated, there is no data input to the data processing device.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 1 (al) shows a block diagram in which a key lock circuit is provided in the keyboard, and FIG. 1 (b) shows an example of a specific configuration of the key lock circuit.

In FIG. 1 [a], the keyboard 10 is connected to the cable 20
Thus, data is exchanged with the main body 30.

The main body 30 may be any device, such as an information processing device such as a word processor or a personal computer, or a control device, as long as it uses the keyboard 10 as an input device.

In the keyboard 10, a key address signal is transmitted from the main body 30 to the keyboard matrix 12 via the decoder 11, and data 13 generated by key operations (hereinafter referred to as key data) from the keyboard matrix 12 is transmitted through the key lock circuit 14, and is converted into keyboard output data. 15 as main body 30
is transmitted to.

In the key lock circuit 14 of FIG. 1(b), one input of the OR circuit 141 is the key data 13, and the other input is determined by the lock switch 143. During normal operation of the keyboard 10, the lock switch 143 is open and the input of the inverter 142 is connected to the pull-up resistor 1.
44 is "1", the output of the inverter 142 is "0", and the same signal as the key data 13 is transmitted as the keyboard output data 15.

Next, when the operator closes the lock switch 143, the output of the inverter 142 becomes "1", and the keyboard output data 15 becomes "1" regardless of the key data 13. At this time, the keyboard output data 15 is continuously outputting 1'', which is a signal corresponding to a state where no key operation is performed on the keyboard 10. In other words, by closing the lock switch 143, the operator's Output of the keyboard matrix 12 due to key operations that are not performed will be prevented.

〔Effect of the invention〕

As explained above, according to the present invention, a key lock circuit is provided in the output signal line of the keyboard, and by opening and closing the switch in the key lock circuit, a signal equal to the key operation data is normally output, while the operator When a keyboard operation is stopped midway, the keyboard output data can be set to a specified signal when no key operation is performed.

Therefore, even if someone else operates the keyboard or physically presses a key when the above-mentioned keyboard operation is stopped midway, the resulting key output will apparently be transmitted to the main body of the information processing device, etc. This means that it will not cause any problems.

[Brief explanation of drawings]

FIG. 1(a) is a block diagram of a keyboard according to an embodiment of the present invention, and FIG. 1(b) is a diagram showing an example of a key lock circuit. 10--Keyboard, 11--Decoder, 12
-・Keyboard matrix, 14-Key lock circuit, 141-OR circuit, 142-・Inverter, 143
・・・−・Lock switch, 144・−Pull amplifier resistor.

Claims (1)

[Scope of Claims] A keyboard that sends key operation data generated in response to key operations to the main body of the device via an output signal line, comprising: means for outputting a signal equal to the key operation data; A key lock comprising means for outputting a predetermined signal when the key is not operated, regardless of the operation, and means for selectively switching between the respective signals obtained from the two means. A keyboard characterized in that a circuit is provided on the output signal line.