JPH01122537A - Matrix switch input device - Google Patents

Abstract

PURPOSE:To shorten the scan processing time by inserting diodes in the opposite direction to each other to a short circuit point and a matrix switch respectively on two lines among a lot of three lines and connecting the short circuit point to the first or the second selecting device. CONSTITUTION:A scanning device M4 selects the preset row line via a selecting device M2 and detects its electric signal. At this time, if a switch S1 inserted with a diode M6 in the forward direction with the electric signal or a switch S2 not inserted with the diode M6 is depressed among three switches S1-S3 formed with the preset lot M5 and row line X1, the same preset signal is detected. If a switch S3 inserted with the diode M6 in the opposite direction to the electric signal is depressed or no switch is depressed, the preset electric signal 12 different from the electric signal 11 is detected. The device 4 then selects the preset lot M5 via a device M3 and detects the electric signal. The depression of three switches can be thereby judged by two scan processings.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention [Field of Industrial Application] The present invention relates to a matrix switch input device that detects a pressed position of a matrix switch.

[Background Art] A conventional matrix switch input device performs a so-called serial scan process, in which an electronic control device 50 as a scan means shown in FIG. The pressed position of the matrix switch 52 is detected by selecting the row line and sequentially selecting all the column lines via the selection switching circuit 53 for all the row lines.

Inventions and proposals regarding the matrix switch input device include Japanese Patent Application No. 144504/1983.

[Problems to be Solved by the Invention] However, the conventional matrix switch input device has the following problems. That is, (a) the number of terminals of the connector 54 of the matrix switch input device, the number of pull-up resistors of the pull-up circuit 55,
The problem is that the number of selection switches of the selection switching circuits 51 and 53 and the number of connection patterns 56 are required to correspond to the number of row lines and column lines, respectively.
In this case, it is necessary to secure a substrate area corresponding to this, so the disadvantage is significant.

(b) In addition, in the above-mentioned scan process, if the numbers of row lines and column lines are X and Y, respectively, the switching (scanning) process of the selection switching circuits 51 and 53 is performed X-Y times for one scan process. must be done. Therefore, there was a problem that the scan processing time was long. The problems (a) and (b) above become more serious as the number of row lines and column lines increases.

The matrix switch input device of the present invention is intended to solve the above problems with a simple configuration.

Structure of the Invention [Means for Solving the Problems] The matrix switch input device of the present invention has a plurality of row lines (Xi to Xn>) and column lines (Yl to Ym), as shown in FIG.
) are arranged in the shape of a matrix switch, and a matrix switch (Ml) which short-circuits or opens a predetermined row line and a predetermined column line when pressed, and
a first selection means (M2) connected to the column line (Yl to Ym);
a second selection means (M3) connected to the first selection means (M2) and the second selection means (M3); M4
) detects the pressed position of the matrix switch (Ml) by scanning the row line (XI to Xn).
Alternatively, a set (M5) is provided in which one end of any three lines of one of the column lines (Yl to Ym) are short-circuited to each other, and the short-circuit is applied to each of the two lines in this set (M5). Diodes (M6) having opposite directions are interposed between the point and the matrix switch (Ml), respectively, and the short-circuit point is connected to the first selection means (M2) or the second selection means (M3).
It is characterized by being connected to.

[Function] The matrix switch input device of the present invention having the above configuration functions as follows.

The scanning means (M4) first selects the first selection means (M2
), a predetermined row line, for example row line X1, is selected and its electrical signal is detected. At this time, three switches (S'l to S3) are formed by the predetermined set (M5) and the row line X1.
), if the switch (Sl) with a diode (M6) interposed in the forward direction of the electric signal or the switch (S2) without the diode (M6>) is pressed, the same predetermined electric signal (hereinafter , electrical signal (referred to as 1) is detected.Also, if a switch (S3) with a diode (M6) interposed in the opposite direction to the electrical signal is pressed, or any switch (Sl to 83) is detected. If neither is pressed, a predetermined electrical signal (different from the above electrical signal ①)
Hereinafter, an electrical signal (hereinafter referred to as "2") is detected. Subsequently, the scanning means (M4) selects the predetermined set (M5) via the second selection means (M3) and detects the electric signal thereof. At this time, a diode (M6) is connected to the electrical signal in the forward direction.
If the switch S3 with a diode inserted or the switch S2 without a diode is pressed, the electrical signal 11
is detected. Further, if the switch S1 is pressed down, or if none of the switches (81 to S3) are pressed down, the electrical signal (2) is detected. Therefore, it is detected which switch (Sl to 33) is pressed by the four combinations of the electric signals 1 and 12. In other words, three switch press determination processes can be performed by performing two scan processes.

[Example] Next, a preferred example will be described with reference to the drawings in order to further clarify the configuration of the matrix switch input device of the present invention.

As shown in FIG. 2, the matrix switch input device of this embodiment has a plurality of row lines X1 to xn and a plurality of column lines y1 to ym (m is a multiple of 3) arranged in each matrix. a selection switching circuit 2 connected to one end of each of the row lines x to Xn and serving as a first selection means for selecting a predetermined row line;
, a selection switching circuit 3 as a second selection means connected to the column lines y1 to ym, and selection switching circuits 2 and 3.
It is comprised of an electronic control device 4 and the like as a scanning means that performs scanning processing of the matrix switch 1 via the matrix switch 1.

The above-mentioned column lines y1 to ym sequentially form sets P1 to Pi in which one end of each three lines is shorted to each other. The short-circuit points of each of these sets P1 to Pi are connected to the selection switching circuit 3 described above via a connector 10 and a pull-up circuit 11, respectively. Further, in each of the sets P1 to Pi, diodes Dco to Dl having opposite directions are interposed between the respective short circuit points and the matrix switch 1 for predetermined two of the three column lines. Note that the pull-up circuit 11 pulls up each short circuit point of the sets P1 to Pl to a predetermined potential. Similarly, pull-up circuits 12 interposed on the selection switching circuit 2 side of the row lines X1 to xn pull up the row lines X1 to xn to predetermined potentials via connectors 13, respectively.

The electronic control device 4 is configured as a logic operation circuit mainly consisting of a well-known CPU 4a, ROM 4b, and RAM 4C, and these and an external C interface circuit 4d interconnected by a bus 4e.

The CPU 4 a of the electronic control device 4 directly switches the selection switching circuit 2 through the signal line 15 and the selection switching circuit 3 through the signal line 16 , and also directly switches the selection switching circuit 2 through the signal line 17 . , the signals output from the selection switching circuit 3 are directly inputted through the signal lines 18, respectively.

The operation of this embodiment having the above configuration will be explained with reference to FIGS. 3 and 4. Here, FIG. 3 shows the switches SW1 to SW3 formed by the batting line X1 in the matrix switch 1 and the column lines Vm-2 to ym of the group Pi, and FIG. 4 shows the switches SW1 to SW3. This shows the "scan determination process" that determines whether or not has been pressed.

When the process shifts to the "scan determination process" executed by the CPU 4a of the electronic control unit 4, first, the selection switching circuit 2 is switched to set the batting line x1 to a low level, and the selection switching circuit 3 is switched to select group Pi. Processing is performed (step 5100). Subsequently, the CPU 4a receives the voltage level of the set Pi (hereinafter referred to as
level v1) is detected and recorded in the RAM 4c (step S'l 10).

At this time, if stitch SW1 or SW2 is pressed down, current flows because the stroke line X1 is at a low level, and the detected level V1 indicates a low level. On the other hand, when the switch SW3 is pressed down, no current flows because the diode DI is interposed in the opposite direction, so the detected level 1 indicates a high level. Similarly, a high level is also indicated when none of the switches SW1 to SW3 is pressed.

Subsequently, in step S120, step 510 described above is performed.
A switching process opposite to 0 is performed. That is, CPU4a
sets the set Pi to a low level and performs processing to select the row line X1. Subsequently, similar to the process in step 8110 above, the voltage level of the row line X1 inputted via the signal line 17 (hereinafter referred to as level v2) is detected and
The process of storing the data in G is performed (step 3130).

At this time, if the switch SW2 or SW3 is pressed down, a current flows because the set P1 is set to a low level, and the detected level indicates a low level. On the other hand, when switch SW1 is pressed down, diode D1-
1, no current flows, so the detected level 2 indicates a high level. Similarly, which switch SW1'
>Even if SW3 is not pressed, it also indicates a high level.

Subsequently, in step 8140, a depression determination process for the switches SW1 to SW3 is performed according to the map shown in Table 1 below, using the stored values of level V1 and ■2.

In Table 1, when level v1 is low level and level V2 is high level, switch SW1, level V1 and V
It is determined that switch SW2 has been pressed when both of 2 indicate a low level, and switch SW3 is determined when level v1 indicates a high level and level v2 indicates a low level,
When levels V1 and V2 both indicate a high level, it is determined that no switch has been pressed.

In step 8150 following step 3140, a process is performed to determine whether a switch other than switches SW1 to SW3 has been pressed, and thereafter, the process can proceed to rRETURNj.

According to the present embodiment described in detail above, the depression determination process for the three switches SW1 to SW3 only requires performing two scan processes (steps 8100 and 5120). Therefore, all X in matrix switch 1
The press determination process for n-Ym switches is 2/3 ・X
It is only necessary to perform scan processing n-Ym times, and the number of scans can be reduced to 2/3 of the conventional number. This provides an excellent effect of shortening the scan processing time and allowing faster determination processing.

In addition, the number of wires from the column lines Y1 to Ym to the selection switching circuit 3 can be reduced to 173 compared to the conventional number, and the number of terminals of the connector 10, the number of pull-up resistors of the pull-up circuit 11, and the number of selection switching circuits 3 can be reduced to 173. The number of selection switches in the switching circuit 3 can also be reduced to 173, which is the conventional number. As a result, the substrate area shown in FIG. 2 can be significantly reduced, and the cost of the product can also be reduced.

The matrix switch input device of the present invention is not limited to the above-mentioned embodiment in any way, but can be implemented in various forms without departing from the gist of the present invention. For example, a so-called membrane touch panel made of a plurality of rectangular transparent conductive films (ITO) as shown in Fig. 5 may be used as the matrix switch. The effect of reducing the board area is particularly large because the wiring must be done.Also, as for the "scan judgment processing" shown in Fig. 4,
The "scan determination process" shown in FIG. 6 may be executed.

In this case, two scan processes (step 8200
, step 8220 or 5230) is the same as the "scan determination process" shown in FIG.
50>, it is possible to determine whether each switch has been pressed without requiring the process of storing it in the RAM 4c (steps 5260 to 5290).

Effects of the Invention According to the matrix switch input device of the present invention, the number of scans can be reduced to 273 times compared to the conventional method, and the scanning processing time can be shortened to perform faster determination processing, which is an excellent effect. In addition, the number of wires from the batting line or column line to each selection switching circuit is 173 compared to the conventional one.
At the same time, the number of terminals of the connector, the number of pull-up resistors, and the number of selection switches of the selection switching circuit can also be drastically reduced compared to the conventional one. Therefore,
This has an excellent effect of reducing the substrate area and reducing the cost of the product.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram illustrating the basic configuration of a matrix switch input device according to the present invention, FIG. 2 is a schematic configuration diagram showing a matrix switch input device according to an embodiment of the present invention, and FIG.
The figure is a detailed diagram showing a part of the inside of the matrix switch 1, FIG. 4 is a flowchart showing the "scan judgment process", FIG. 5 is an explanatory diagram showing a membrane touch panel as the matrix switch 1, and FIG. 6 is a second implementation. Flowchart 1-1 showing an example of "scan determination processing" FIG. 7 is a schematic configuration diagram showing a conventional matrix switch input device. Ml...Matrix switch M2...First selection means M3...Second selection means M4...Scanning means M5...Set M6...Diode 1...Matrix switch 2.3. ...Selection switching circuit 4...Electronic control device Pl or Pi...Group Dl or Dl...Diode agent Patent attorney Tsutomu Adachi (one idiot) Figure 4 Figure 6 Figure 5

Claims (1)

[Scope of Claims] A matrix switch in which a plurality of row lines and column lines are arranged in a matrix, and which short-circuits or opens a predetermined row line and a predetermined column line by pressing the switch; a first selection means connected to the column line or the row line, and a second selection means connected to the column line or the row line, and the scanning means performs scanning processing via the first selection means and the second selection means. In the matrix switch input device that detects the pressed position of the matrix switch by performing diodes having opposite directions are interposed between the short-circuit point and the matrix switch for each of the two lines, and the short-circuit point is connected to the first selection means or the second selection means. A matrix switch input device featuring: