TW201401106A - Keyboard apparatus and detection method for status of keys of the keyboard apparatus - Google Patents

Abstract

A keyboard apparatus and a detection method for status of the keys of the keyboard apparatus are disclosed. The keys of the keyboard apparatus respectively receive a plurality of scan output signals, and respectively transport a plurality of scan input signals. The steps of the detection method include: calculating a plurality of time differences between a time point which each of the scan output signals is enabled and time points which the scan input signals are enabled; obtaining a status of each of the keys which is corresponding to each of the time differences by comparing each of the time differences and a preset value.

Description

Keyboard device and method for detecting button status

The present invention relates to a method for detecting a button state of a keyboard device, and more particularly to a method for detecting a button state of a keyboard device capable of avoiding a ghost key phenomenon.

Please refer to FIG. 1 , which illustrates a conventional keyboard device 100 . The keyboard device 100 includes four buttons SW1 to SW4. When the detection operation of the pressed state of the buttons SW1 to SW4 is performed, the scan output signals SCO1 and SCO2 are sequentially enabled. The buttons SW1 and SW2 transmit the scan input signals SCI1 and SCI2 according to the pressed state when the scan output signal SCO1 is enabled, and the buttons SW3 and SW4 are pressed according to the state when the scan output signal SCO2 is enabled. The scan input signals SCI1 and SCI2 are transmitted. Therefore, when the different scan output signals SCO1 and SCO2 are enabled to detect whether the scan input signals SCI1 and SCI2 are also enabled, the pressed state of the buttons SW1 to SW4 can be known.

Since the buttons SW1 and SW3 transmit the scan input signal SCI1 through the same transmission line, and the buttons SW2 and SW4 transmit the scan input signal SCI2 through the same transmission line. Therefore, as can be clearly seen from the drawing of FIG. 1, when the buttons SW1, SW3, and SW4 are pressed and the button SW2 is not pressed, and the scan output signal SCO1 is enabled, the enabled scan output signal SCO1 is enabled. Will follow through The scan input signal SCI2 is generated by the pressed buttons SW1, SW3, and SW4. That is, although the button SW2 is not pressed, when the scan output signal SCO1 is enabled, the scan input signal SCI2 is still activated, and the button SW2 is erroneously judged to be pressed. This phenomenon of misjudgment is the phenomenon of the so-called ghost key.

The invention provides a method for detecting a button state, which effectively solves the problem of ghost keys that may be generated.

The invention provides a method for detecting a button state, which is suitable for a keyboard having a plurality of buttons, wherein the buttons respectively receive a plurality of scan output signals and respectively transmit a plurality of scan input signals. The step of detecting the button state includes: calculating a time difference between a time point when each scan output signal is enabled and a time point at which the scan input signal is enabled when each scan output signal is enabled; and then, according to the comparison time difference and The preset value is obtained to obtain the pressed state of each button corresponding to each time difference.

The invention provides a keyboard device comprising a plurality of buttons and a button state detector. The buttons respectively receive a plurality of scan output signals and respectively transmit a plurality of scan input signals. The button state detector is coupled to the button, and the button state detector calculates a time difference between the time at which each scan output signal is enabled and the time at which the scan input signal is enabled, when the scan output signals are enabled, and The pressed state of each button of each scan input signal corresponding to each time difference is obtained according to the comparison time difference and the preset value.

Based on the above, the present invention detects the scan output signal by transmitting to the button. The time difference between the number and the enabled time point of the scan input signal transmitted by the button determines whether the button is genuinely pressed or the so-called ghost key is misjudged. In this way, the pressing state of the keyboard device can be detected more accurately, so that all the buttons can effectively generate the output.

The above described features and advantages of the present invention will be more apparent from the following description.

Please refer to FIG. 2 , which is a flowchart of a method for detecting a button state according to an embodiment of the present invention. The method for detecting the state of the button of this embodiment is for a keyboard having a plurality of buttons. The key arrangement may refer to FIG. 1 , and the buttons arranged in the same row (for example, the buttons SW1 and SW3 ) transmit the scan input signal (for example, the scan input signal SCI1 ) through the same transmission line, and are arranged in the same column. The buttons (such as buttons SW2 and SW4) receive a scan output signal (eg, scan output signal SCO2) through the same transmission line.

In the step of detecting the state of the button state, first, when the pressing state detection operation of the buttons SW1 to SW4 is performed, the scan output signals SCO1 to SCO2 are sequentially enabled in different time intervals, and the detection is performed. The pressed state of the button that receives the enabled scan output signal is measured. For example, the scan output signal SCO1 is enabled in the first time interval, and the pressed state of the buttons SW1 and SW2 receiving the scan output signal SCO1 is known by measuring the scan input signals SCI1 and SCI2. and And, in the time interval after the scan output signal SCO1 is converted to disabled, the scan output signal SCO2 is enabled, and the scan input signals SCI1 and SCI2 are measured to know the buttons SW2 and SW4 of the scan output signal SCO2. Pressed state.

The above-mentioned enabled actions on the scan output signals SCO1 and SCO2 are, for example, converting the scan output signals SCO1 and SCO2 from a logic low level to a logic high level, and in contrast, the scan output signals SCO1 and SCO2 are disabled. Then, the scan output signals SCO1 and SCO2 can be converted from the logic high level to the logic low level. Of course, the enabled actions of the scan output signals SCO1 and SCO2 can also be defined as being converted from the logic high level to the logic low level, and the scan output signals SCO1 and SCO2 being disabled, the scan output signal SCO1 can be made. And SCO2 is converted to a logic high level by a logic low level.

In the step S210 of the present embodiment, the time difference between the time when each scan output signal is enabled and the time point at which the scan input signal is enabled is calculated when each scan output signal is enabled. Specifically, please refer to FIG. 3. FIG. 3 is a waveform diagram of a method for detecting a button state according to an embodiment of the present invention. Wherein, the buttons SW2, SW3, and SW4 are pressed and the button SW1 is not pressed as an example, the scan output signal SCO1 is enabled at the time point T1, and during the period TEN during which the scan output signal SCO1 is enabled, the input signal SCI2 is scanned. And SCI1 is sequentially converted to an enabled state (from a logic low level to a logic high level) at time points T3 and T2.

The calculation method of the time difference between the time point T1 and the time point T3, and the time point T1 and the time point T2 can be generated by the timing action The timing result is obtained by CNT1. The timing action can be started at the time when the scan output signal SCO1 is enabled, and the timing result CNT1 is counted from 0, and the time value CNT1 is obtained at the time point T3 and the time point T2, respectively, and the time can be obtained. Point T1 and time point T3, and the time difference between time point T1 and time point T2.

It should be noted that, as shown in FIG. 1 , when the buttons SW2 , SW3 , and SW4 are pressed and the button SW1 is not pressed, the scan input signal SCI1 is sequentially passed through the buttons SW2 , SW4 , and SW3 according to the scan output signal SCO1 . It is generated by transmitting to the button SW1 to generate a transmission line for scanning the input signal SCI1. That is, the scan input signal SCI1 is equivalent to the scan output signal SCO1 being generated by a long time delay.

As can be understood from the above description, the enabled time point T2 of the scan input signal SCI1 transmitted by the button SW1 in which the ghost key phenomenon occurs is apparently higher than that of the scan input signal SCI2 transmitted by the button SW3 in which the ghost key phenomenon has not occurred. The time T3 is late to be enabled. According to this, in step S220, according to the time difference calculated by the comparison step S210 and the preset value, the pressed state of each button corresponding to each time difference can be obtained.

Specifically, in the same manner as FIG. 3, in the period TEN during which the scan output signal SCO1 is enabled, by detecting the time points T2 and T3 at which the scan input signals SCI1 and SCI2 are enabled, and at the time point T3 and time point T2 are used to capture the timing result CNT1 generated by the timing operation to obtain the time point T1 at which the scan output signal SCO1 is enabled and the time points T2 and T3 at which the scan input signals SCI1 and SCI2 are enabled, respectively. The difference between. By comparing the time difference between the time point T1 and the time point T2 to be greater than the preset value, it can be determined that in the period TEN during which the scan output signal SCO1 is enabled, the so-called ghost key occurs in the button SW1 that generates the scan input signal SCI1, actually It was not pressed. In contrast, the time difference between the comparison time point T1 and the time point T3 is less than the preset value, and it can be determined that the button SW2 that generates the scan input signal SCI2 is actually pressed during the period TEN during which the scan output signal SCO1 is enabled. of.

Incidentally, when the scan output signal SCO1 is switched from the enabled state to the disabled state, the timing action is reset and the timing result CNT1 is reset to zero.

Referring to FIG. 4, FIG. 4 is a flowchart of another embodiment of a method for detecting a button state according to the present invention. First, in step S410, the output signal is enabled to be scanned, and the timing operation is synchronously started in step S420. Then, the enabled time point of the scan input signal is detected, and thereby the time difference between the enabled time point of the scan input signal and the enabled time point of the scan output signal is converted. In step S430, the time difference is compared with a preset preset value. If the time difference is greater than or equal to the preset value, it indicates that the button has a ghost key occurrence, and the key is recorded as a ghost key in step S440. And step S450 is performed. If the result of the determination in step S430 is that the time difference is small, the step S450 is also performed.

Step S450 performs an operation of whether the scan output signal is turned off, and if the scan output signal is disabled, the reset operation of the timed operation of step S460 is performed. If the scan output signal continues to be enabled, step S450 is continuously performed.

Referring to FIG. 5, FIG. 5 is a schematic diagram of a keyboard device 500 according to an embodiment of the present invention. The keyboard device 500 includes a keyboard array 510 and a button state detector 520. The keyboard array 510 has a plurality of buttons for receiving the scan output signals SCO1~SCON and outputting the scan input signals SCI1~SCIM. The button state detector 520 is coupled to the buttons in the keyboard array 510 and receives the scan output signals SCO1 S SCON and the scan input signals SCI1 SCSCIM. The button state detector 500 calculates a plurality of time differences between the time point at which each of the scan output signals SCO1 to SCON is enabled and the time at which the scan input signals SCI1 to SCIM are enabled when each of the scan output signals SCO1 to SCON is enabled. And according to the comparison time difference and the preset value, the pressed state of each button of each scan input signal SCI1~SCIM corresponding to each time difference is received.

The detection operation of whether the button state detector 520 performs a ghost key phenomenon in the button is described in detail in the foregoing embodiments, and will not be described below. In addition, the button state detector 520 can have a built-in timer 521 for performing the timing operation, and obtain the time point when each scan output signal SCO1~SCON is enabled and the time when the scan input signals SCI1~SCIM are enabled. Multiple time differences for points.

In summary, the present invention determines whether a key of a keyboard device has a ghost key by calculating a time difference between a time point at which each scan output signal is enabled and a time point at which the scan input signal is enabled. As a result, the misjudgment action of the button press due to the ghost key phenomenon can be eliminated. According to this, all the button states can be effectively output correctly, which greatly improves the performance of the keyboard device.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100, 500‧‧‧ keyboard device

510‧‧‧Keyboard Array

520‧‧‧Key Status Detector

SW1~SW4‧‧‧ button

SCO1~SCON‧‧‧ scan output signal

SCI1~SCIM‧‧‧ scan input signal

S210~S220, S410~S460‧‧‧ steps of detecting the state of the button

T1~T3‧‧‧ time point

CNT1‧‧‧ timing results

FIG. 1 illustrates a conventional keyboard device 100.

2 is a flow chart of a method for detecting a button state according to an embodiment of the present invention.

FIG. 3 is a waveform diagram of a method for detecting a state of a button according to an embodiment of the present invention.

4 is a flow chart showing another embodiment of a method for detecting a button state according to the present invention.

FIG. 5 is a schematic diagram of a keyboard device 500 according to an embodiment of the present invention.

S210~S220‧‧‧Steps for detecting the state of the button

Claims (13)

A method for detecting a button state is applicable to a keyboard having a plurality of buttons, wherein the buttons respectively receive a plurality of scan output signals and respectively transmit a plurality of scan input signals, including: calculating each scan output signal is caused a time difference between a time point at which each of the scan output signals is enabled and a time point at which the scan input signals are enabled; and comparing the time differences and a preset value to obtain a corresponding time difference The pressed state of each of the buttons of the scan input signal. The method for detecting a button state as described in claim 1, wherein when each of the scan output signals is enabled, each of the scan output signals is enabled and the scan input signals are enabled. The step of the time difference of the time points includes: starting a timing action according to the enabled state of each of the scan output signals; and extracting a plurality of timings generated by the timing action when the scan input signals are enabled respectively The result is to obtain the time differences. The method for detecting a button state as described in claim 2, wherein the step of initiating the timing action according to the enabled state of each of the scan output signals comprises: when each of the scan output signals is enabled, Start the timing action. For example, the method for detecting the state of a button as described in claim 3 of the patent application includes: The timing action is reset when each of the scan input signals is enabled to be disabled. The method for detecting a state of a button as described in claim 2, wherein the step of capturing the timing results generated by the timing action to obtain the time differences when the scan input signals are enabled includes: Detecting whether the scan input signals are enabled; and when each of the scan input signals is enabled, capturing the timing result generated by the timing action to obtain the time differences. The method for detecting a button state according to claim 1, wherein the comparing the time differences and the preset value to obtain a pressed state of each button of each of the scan input signals corresponding to each of the time differences is obtained. The step of determining whether the time difference is greater than or equal to the preset value; when each time difference is greater than or equal to the preset value, each of the buttons corresponding to the time difference is in an unpressed state; and when each time difference is less than In the preset value, each of the buttons corresponding to the time difference is in a pressed state. A keyboard device includes: a plurality of buttons respectively receiving a plurality of scan output signals and respectively transmitting a plurality of scan input signals; and a button state detector coupled to the buttons, the button state detection Calculating, when the respective scan output signals are enabled, a time difference between a time point at which each of the scan output signals is enabled and a time point at which the scan input signals are enabled, and comparing the time differences and a preset Value to get The pressed state of each of the buttons corresponding to each of the scan input signals corresponding to the time difference is received. The keyboard device of claim 7, wherein the button state detector activates a timing action according to an enabled state of each of the scan output signals, and respectively when the scan input signals are enabled. A plurality of timing results generated by the timing action are taken to obtain the time differences. The keyboard device of claim 8, wherein the button state detector comprises: a timer for performing the timing action. The keyboard device of claim 9, wherein the timer initiates the timing action when each of the scan output signals is enabled. The keyboard device of claim 9, wherein the timer resets the timing action when each of the scan input signals is enabled to be disabled. The keyboard device of claim 8, wherein the button state detector detects whether the scan input signals are enabled, and captures the timing action when each of the scan input signals is enabled. The generated count value is used to obtain each of the timing results of each of the buttons corresponding to each of the scan input signals. The keyboard device of claim 8, wherein the button state detector determines whether the time differences are greater than or equal to the preset value, and when each time difference is greater than or equal to the preset value, the button The state detector determines that each of the buttons corresponding to the time difference is in an unpressed state. When each of the time differences is less than the preset value, the button state detector determines that each button corresponding to the time difference is pressed. status.