JPS6080319A - Touch switch device - Google Patents

Abstract

PURPOSE:To attain simply the disconnection wire check of a touch electrode and the circuit operation check by displaying a capacity component of the touch electrode. CONSTITUTION:Transparent touch electrodes 3 (T1-T9) are arranged in, e.g., 3X3 matrix form on the upper face of a transparent glass 2 fixed to the front face of a case 1 of an electronic wrist watch with computing functions, and when the touch electrode 3 is touched to input manually a character pattern such as a desired numeral, the change in the capacitive component is detected, a coordinate position is inputted one after another and then the input of the character pattern is inputted. A digital display section 4 of a liquid crystal display device or the like is provided to the front face of the front glass 2, and a pointer display section 5 is arranged at the lower side. When a touch input exists, an electrode number [1] is displayed on e.g., the 2nd digit of the display section 4, a count value [036] of floating capacitive component is displayed on the 3rd- 5th digits, a count value [107] of the contact capacitance component is displayed on the 6th-8th digits respectively, the disconnection wire state of the touch electrode and the operating state of the circuit are checked quantitatively by numerals.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a touch switch device used as an external input means for electronic wristwatches and small electronic calculators.

[Prior art and its problems]

BACKGROUND ART In recent years, touch switches that perform switching by detecting the amount of change in a capacitance component when a touch electrode is touched by a human body have been used as external input means for electronic wristwatches with calculation functions. However, in this type of test, testers manually operated the test to check whether the touch detection circuit was working properly or whether the touch electrode was disconnected. , was extremely unreliable.

[Purpose of the invention]

The present invention was made against the background of the above-mentioned circumstances, and its purpose is to provide a touch switch device that can easily and reliably check the operation of a touch detection circuit, the disconnection of touch electrodes, etc. There is a particular thing.

[Key points of the invention]

In order to achieve the above-mentioned object, the gist of the present invention is to provide a capacitance detection type touch switch device with means for displaying a capacitance component of a touch electrode.

〔Example〕

Hereinafter, the present invention will be specifically described based on an embodiment shown in the drawings. Note that this embodiment shows an example in which a capacitive detection type touch switch device and a character recognition device, which will be described later, are incorporated into an electronic wristwatch with a calculation function. The touch switch device, as shown in FIG. 1, includes a transparent surface glass 2 press-fitted onto the front of a watch case 1;
Further transparent touch electrodes 3 (T, ~T,) are placed on the top surface of
Arranged in a 3x3 matrix along the Y coordinate system,
These nine touch electrodes are, for example, 11×11=121
It is formed by processing the coordinate position of drowsily. In order to input a desired character pattern such as a number by hand, when a human body such as a finger touches the touch electrode, the amount of change in the capacitance component at that time is detected and the coordinate position is input, thereby inputting the character pattern. Pattern C In this embodiment, numbers and symbols for four arithmetic operations are input. This kind of technology is
Patent application already proposed by the applicant (Japanese Patent Application No. 55-356)
No. 60, title of invention: touch switch device) may be used. Note that for convenience of explanation, the touch electrodes T, ~T0 are as follows:
As shown in Figure 2, the numbers "1" to "9" in decimal notation are
” is shown below.

Further, in this embodiment, under the back surface of the front glass 2, a digital display section 4 consisting of a liquid crystal display device etc. is disposed above it, and a mechanical pointer display section 5 is disposed below.
is installed. That is, this embodiment has a configuration in which the digital display section 4 and the pointer display section 5 are arranged below the touch electrodes that constitute the touch switch device, and such a laminated structure makes it possible to miniaturize the wristwatch. It is something. Further, one side of the watch case 1 is provided with mode switches SI and S1 for switching various modes, and the other side is provided with a crown SR for correcting the position of the pointer on the pointer display section 5.

As shown in FIG. 3, the digital display section 4 is a numeric display body 4a that can digitally display up to eight digits.

It is configured to include a function display body 4b representing the four arithmetic operations [÷J, rXJ, "-", "+", etc.

In addition to displaying the numeric display 4a, time data, calculation result data, etc., it particularly displays test result data of touch electrodes, which will be described later.

Next, the overall circuit configuration of the electronic wristwatch with calculation function will be explained with reference to FIG. When the mode switch S is operated, a pulse signal is output from the one-shot circuit 11, and the output state of the trigger clip-flop (T=Fp) 12 is inverted. The Q and Q outputs of this T-FF 12 are sent out as a mode designation signal X1Y via the corresponding analogues 13 and 14. In this case, signal X is a signal specifying clock mode, and signal Y is a signal specifying computer mode. Further, when the mode switch S is operated, a pulse signal is output from the one-shot circuit 15, and the output state of the T-FF 16 is reversed. The Q output of this T-FFI 6 is sent out as a mode designation signal Z. In this case, the signal Z specifies the check mode in which the touch switch device is tested. In addition, in the above check mode, operate the mode switch "S2 to reverse the T-FF16,
When the check mode is released, AND gates 13 and 14 are opened by the output of T-FF 16, and T-FF
Depending on the output of 12, the mode is set to clock mode or calculator mode. Also, T-FF16's Q
The output is input to the AND gate 17 as an open/close signal. In other words, when the clock mode or computer mode is set, the calculation power of the T-FF 16 is 1.
'', when the mode switch S is operated, the output of the one-shot circuit 15 is sent to SR via the AND gate 17.
Type rough flip-flop SR-FF) 18 set terminal S
is input. 5R-FF18 is a mode setting circuit,
When the Q output is 1'', the set mode is set. In this set mode, the stray capacitance components of the nine touch electrodes mentioned above (stray capacitance such as touch electrode wiring capacitance and 0MO8IC gate capacitance) will be explained later. It executes the process of writing data into the memory in correspondence with each touch electrode.The Q output of the 5R-FF 18 is input as a signal S to the touch input section 19 and the character recognition control gls 20, respectively. The 5R-FF 18 is configured to be reset by the output of the character recognition control section 20 when writing of the stray capacitance component to the last ninth touch electrode is completed.

In the touch input M19, data W of "11 to "9" for sequentially sensing nine touch electrodes is input to the character recognition control unit 2.
It is input sequentially starting from 0. In addition, the touch input unit 11t executes operations based on the input mode designation signals X, Y, and zVc2, and receives, for example, a 32Hz rectangular wave signal A and a 1024Hz clock pulse wave input from the character recognition control unit 2o. Execute touch input processing according to the following. Then, the touch input section 19 outputs the data M obtained by the touch input processing to the character recognition control section 2o.

The character recognition control unit 2o detects the coordinate position of the touch electrode according to the input data M, and converts the input character pattern from each detected coordinate position into RlOM (character recognition according to the contents of Read Only Memo January 21). This type of technology can be utilized in the patent application already proposed by the present applicant (Japanese Patent Application No. 57-232559, title of invention: character recognition device).The number "o" is stored in the ROM 21.
~ "9", a function symbol for four arithmetic operations A vector string (described later) of each corresponding standard character pattern is stored as data, and the character recognition control unit 20 uses the standard vector string and the input character pattern vector. Character recognition is performed by comparing the strings (described later). In addition,
The character recognition control unit 20 receives the mode designation signals X, Y,
Z is input.

Character data output from the character recognition control section 20 is input to the clock section 23 via the AND gate 22, which is opened according to the clock mode designation signal X, and is also opened according to the computer mode designation signal Y. The data is input to the computer section 25 via the AND gate 24. In this case, the clock unit 23 corrects clock data such as time according to the input character data, and the calculator unit 25 executes four arithmetic operations according to the input character data. Therefore, clock 1
1s23 and the output data of the computer section 25 are sent to the display switching circuit 26. Further, test result data N, , To, and Tx of touch electrodes and the like outputted from the touch input section 19 are input to the display switching circuit 26 via an OR gate 27 . The display switching circuit 26 switches the output data of the clock section 23, the calculator section 25, and the touch input section 19 according to the input mode designation signals XSY and Z, and selectively outputs the data on the digital display section 4. This is what is displayed.

Next, the configuration of the touch input section 19 will be described in detail with reference to FIG. In addition, in the touch switch device of this embodiment, when the watch case is at one potential and the touch electrodes T1 to T9, which are insulated from the watch case, are brought into contact with the human body, an electric path from the watch case to the human body to the touch electrode is established. A contact capacitance component is formed by the human body. Touch electrode T, ~T
9 are connected to the input sides of the corresponding transmission gates G1 to G. The transmission gates G1-G are AND gates AN, ~A to which signals &, ~a, sequentially output from the decoder 31 in a time-division manner correspond to
It is turned on and off by inputting it through N, and the respective output sides are connected together and then connected to a single resistance component R. That is, the transmission gates G, ~G0 connect each of the touch electrodes T1 to T to a single resistance component R in a time division manner, and connect the series circuit of each touch electrode and the single resistance component R in a time division manner. It is formed by dividing.

The data W is input to the decoder 31 through an AND gate 32 and an OR gate 33, or a counter 34.
The count value data of is inputted sequentially through the AND gate 35 and the OR gate 33, whereby the decoder 31
Decoded outputs a, to a0 are output in a time-division manner. In addition,
The AND gate 32 is opened and closed according to the output of the OR gate 36 to which the mode designation signals X, Y, and S are respectively input, and the AND gate 35 is opened and closed according to the mode designation signal Z. The counter 34 has a signal S input to its preset terminal via an inverter 37, and is preset to 1'' in decimal in synchronization with the rise of the signal S, and a signal θ, which will be described later, is input to its +1 input terminal. The content is incremented by +1 each time it is given, and the count value data corresponds to the touch electrode number and is sent out as digitally displayed data N.

On the other hand, the rectangular wave signal A is a signal synchronized with data W, and C
It is input to the MOS inverter 38. The CMOS inverter 38 consists of a P-channel MO8) transistor 39 and an N-channel MO8) transistor 40, and each transistor 39,40 is turned on and off according to a square wave signal.
FF controlled. In this case, a high potential VDD (logical value "1") is connected to the source side of the P-channel MO8) transistor 39.
A low potential Vss (logical value "'O") is applied to the source side of the transistor 40 (N-channel MO8). The drain sides of each transistor 39 and 40 are connected via a resistor R, respectively. This resistance R and P
Channel MO8) The signal output from the connection point of the transistor 39 is inverted by the inverter 41 and becomes the signal B. Note that the signal B is a signal to be determined that is used to determine whether or not a human body is in contact with the touch electrode, and whether there is a touch or not. The signal B to be determined is input to the Nantes gate 42. A signal S is input to the other input terminal of the Nant gate 42, and when the signal S is 0'', the signal to be determined B
Regardless, an output of '1'' is obtained from the Nant gate 42 and input to the AND gate 43.AND gate 4
3 is deregulated when the output signal of the Nant gate 42 and the input rectangular wave signal A are "1", outputs a clock pulse, and inputs it to the counter 44. This counter 44 is reset at the rising edge of the rectangular wave signal A, and executes the counting operation of the output (clock pulse) of the AND gate 43.Thus, the count value of the counter 44 is
The data is input to and written into RAM (random access memory) 45.

The RAM 45 has address areas corresponding to the number of touch electrodes, and each address area is addressed according to the data W output from the OR gate 33 or the count value of the counter 34, and the contents of the counter 44 are stored in the designated address area. is written.

In this case, read and write operations of the RAM 45 are performed by inputting the signal S as the read/write signal R/W. Thus, the content amount read from the designated address area of the RAM 45 is the content n of the counter 44.
The signals are also input to the comparator circuit 46, respectively.

The comparator circuit 46 detects whether the input data n to m has reached n2m each time the contents of the counter 44 are counted up, and when it detects that n≧m is in the relationship, it sets a logical value. A signal C of "1" is output. This signal C is inverted by an inverter 47 and then sent to a counter 48 as a reset signal. The counter 48 counts the clock pulses, and the count data is stored in the latch 4.
Sent to 9th. In this case, the latch 49
The contents of the counter 48 are taken in in synchronization with the rising edge of the latch 49, and the contents of the latch 49 are given to the e>ε detection circuit 50. The e>ε detection circuit 50 ensures the safety of touch detection by detecting whether the content e of the latch 49 exceeds a certain value ε, which will be described in detail later.
By detecting g〉ε, a 1'' signal is output, directly to the AND gate 51, and directly to the AND gate 52 by the inverter 53.
Enter via. The AND gates 51 and 52 are opened by inputting the signal B to be determined via the delay circuit 54, and the output of the AND gate 51 is 5R-F.
1 is applied to the set terminal S of the F55, and the output of the AND gate 52 is applied to the reset terminal R of the 5R-FF55.

This 5R-FF55 is a touch presence/absence determination circuit, and its Q
Output corresponds to touch, and mutual output corresponds to touchless.
The Q output is sent out as a signal g, and the mutual output is input to the one-shot circuit 56 and then to the delay circuit 57.
The signal e is sent out via the signal e.

On the other hand, the output of the CMOS inverter 38 is
After being reversed at 1, it was further reversed at 58,
It is input to AND gate 59. This and gate 59
Furthermore, a signal g is input together with a mode designation signal Z,
Therefore, in the check mode, when a touch is detected, the AND gate 59 goes high in synchronization with the rising edge of the signal B (in synchronization with the rising edge of the inverter 58).
The output signal is inputted to the one-shot circuit 60. The one-shot circuit 60 is an AND gate 59
A pulse signal f is output in accordance with the output of , the AND gate 61 is opened, and the output data of the RAM 45 is transferred via the AND gate 61 to the latch 621C. At the same time, the pulse signal f causes the AND gate 63 to open,
Furthermore, the output of the AND gate 63 opens the AND gate 64 and transfers the output data V of the latch 49 to the latch 65 via the AND gate 64. Latches 62 and 65
is one whose contents are cleared according to signal e,
The output R of the latch 65 is input to a comparator circuit 66 and compared with the output data (2) of the latch 49.

The comparator circuit 66 compares the magnitudes of the input data R and V, and upon detecting the relationship V>R, outputs a signal of 1'' and opens the AND gate 63. Therefore,
The latch 65 stores the maximum value of the output data l of the latch 49 while the signal g is '1'', in other words, the maximum value of the output data l of the latch 49 obtained when a touch is detected.

The output data of the latch 63 is the data T mentioned above. Furthermore, the output data of the latch 65 is the display data sent out as the above-mentioned data Tx. On the other hand, the output data M of the latch 49 is supplied to the character recognition control section 20.

Next, the operation of the above embodiment will be explained. First, the operation of the touch input circuit 19 in the set mode will be explained with reference to the timing chart shown in FIG. In the set mode, the mode switch S is operated once while the hole output of the T-FFI 6 is set to "1", in other words, the mode is set to clock mode or computer mode.

As a result, an output is obtained from the one-shot circuit 15,
It is sent through the AND gate 17 and sets the 5R-FF 18. Therefore, the signal S, which is the set output of the 5R-FF 13, is input to the touch input section 19 and the character recognition control section 20, respectively. As a result, the touch input section 19
The character recognition control unit 20- then operates in the set mode.

That is, the character recognition control unit 20 outputs data W for sequentially sensing the touch electrodes T1 to T0 in synchronization with the input of the signal S, and supplies it to the touch input gA19. In this case, the touch input section 19 has data W as shown in FIG.
At the same time, a rectangular wave signal A and a clock signal are input. Note that the data W is output in synchronization with the rectangular wave signal A, as shown in FIG. Thus, in the set mode, the data W supplied to the touch input section 19 is the signal S.
The signal is sent to the decoder 31 via the AND gate 32, which is opened by . That is, data W is input to the decoder 31 in the set mode. First, when the data W is "0", the decoder 31 detects that the data W is "0".
0'', a high level signal al (see FIG. 6) is output. As a result, the AND gate AN outputs a signal of '1'' in synchronization with the rectangular wave signal A, so the transmission gate G is turned on, and therefore the series circuit of the touch electrode T and the CMOS inverter 38 As a result, the signal to be determined B, which is an inverted signal of the output of the CMOS inverter 38, is generated by a time T relative to the rise of the rectangular wave signal A, as shown in FIG.
This will delay its rise. This delay time T> corresponds to a stray capacitance component with respect to the touch electrode T. The signal to be determined B is input to the Nant's gate 42, but the output of the Nant's gate 42 is 61" until the signal to be determined B rises. Now, when the rectangular wave signal A rises, While the contents of the counter 44 are reset and the output of the Nant gate 42 is 1'',
The counter 44 performs the counting operation of the clock pulse generator. When the signal B to be determined rises with a delay of time T0 after the rise of the rectangular wave signal A as shown in FIG. 6, the output of the Nant gate 42 becomes 1', so the counting operation of the counter 44 is stopped. Ru. Therefore, in this case, the counter 44 obtains a counter value for the stray capacitance component of the touch electrode T□. This count value R,A
M45+c sent. At this time, the RAM 45 receives the signal S'
1", it is set to a state where data can be written when in the trench mode and set mode, and the data WV
c Therefore, since the first address area is specified, the above count value will be written to the first address area of the RAM 45.

Next, when the data W becomes "1", the touch electrode T is sensed in the same way as described above, and the count value of the stray capacitance component for the touch electrode T2 is written to the next q address area of A, M45. It will be done.

In this way, the touch electrodes are sequentially addressed according to the data W, so that the count value of the stray capacitance component for each touch electrode is sequentially written into the RAM 45. That is, the count value written in the RAM 45 is the delay time T of the signal to be determined B with respect to the rectangular wave signal A due to the influence of the stray capacitance component of each touch electrode T, -T.

[These are the corresponding values. Note that when the writing process for all touch electrodes in the RAM 45 is completed, the character recognition control unit 20 resets the 5R-FFts and automatically cancels the set mode.

Next, the operation of the touch input section 19 in the manual tick mode will be explained with reference to the timing chart shown in FIG. In the check mode, the output state of the T-FF16 is reversed by operating the mode switch S once in the watch mode or the computer mode.
It is set by setting the mutual output of 6 to 1''.Then, when the touch input section 19 automatically cancels the set mode, the signal S falls at the same time.
The falling edge of the signal S (inverter 37
"1" is preset in synchronization with the rise of Furthermore, in the check mode, the contents of the counter 34 are input to the decoder 31 instead of the data W. Therefore, the decoder 31 first outputs the signal a to sense the touch electrode T1. As a result, similarly to the above case, the transmission gate G is turned on by the decode output &, the touch electrode T1 and the CMOS inverter 38 are connected in series, and the signal to be determined B is transmitted to the touch electrode T.
, the time T corresponding to the stray capacitance component of .

(See Figure 7). On the other hand, RAM4
5 is set to a data readable state by canceling the set mode, and its start address area is designated by the output of the counter 34. Therefore, comparison circuit 4
6, the output data n of the counter 44 is stored in the RAM 4.
At the time when the data m read from the first address of 5 is reached, that is, when the signal to be determined B rises, it becomes "1".
outputs signal C. As a result, the counter 48 starts counting clock pulses in synchronization with the inverted signal of the inverter 47, and the contents of the counter 49 are read into the latch 49 in synchronization with the rising edge of the signal B to be determined. e>ε is supplied to the detection circuit 50. By the way, since the stray capacitance component changes depending on the environmental conditions, the above value of ε should be set to 2 to 3 in consideration of the fluctuation of the stray capacitance component or the counting error of the counter, and the stray capacitance component should be set slightly larger. The process of g>ε is executed to obtain the value of g>ε. That is, the processing of e>ε takes into account the safety of whether there is a touch or not. When the value of e is less than or equal to ε, the output of the detection circuit 50 is 0'', and therefore the output of the inverter 53 is 1'', so the output of the AND gate 52 is After a predetermined time delay, the signal becomes '1' and is input to the reset terminal R of the 5R-FF 55. In this case, 5R-FF55
is in the set mode and the output is "1", so at this point, the output state of 5R-FF55 is:
As shown in FIG. 7, it remains in the set mode. So, the Qffl force of 5R-FF55 is 0'',■
Since the output is set to "1", the touch electrode 'I
”, [No touch is detected, and in this case, as shown in FIG. 7, no output of signals f and e is obtained.

When the touch electrode T1 is touched to inspect the state while the touch electrode T is being sensed, the signal B to be determined has a delay M with respect to the rectangular wave signal A, as shown in FIG. is the time T corresponding to the combined capacity of the floating capacitance component and the contact vessel component. +Tx, the signal to be determined B has not yet risen at the time when the comparison circuit 46 outputs a signal of 1''. Therefore,
The contents of the counter 48 written into the latch 49 correspond to the delay time TX of the contact capacitance component. Since the count value corresponding to this delay time Tx is supplied to the e>ε detection circuit 50, the output of this detection circuit 50 becomes 1'', and therefore, while the AND gate 51 is opened, the AND gate 52 is closed. Therefore, 5
As shown in FIG. 7, the output state of the R-FF 55 is inverted after a predetermined time delay after the signal B to be determined rises, and its Q output becomes "1" and the Q output becomes I'0. A touch on the touch electrode T is detected, and the signal g becomes 1''. As a result, when a touch is detected in the check mode, a pulse signal is obtained as shown in FIG. 7 in synchronization with the rise of the inverted signal of the signal to be determined B, and the AND gate 61 is released from regulation. As a result, the output data of the RAM 45, in other words, the count value for the stray capacitance component of the touch electrode T is written into the latch 62. At the same time, the pulse signal f is input to the AND gate 63, but this AND gate 63 is deregulated in accordance with the output of the comparison circuit 66, so the relationship ■>R is established in the comparison circuit 66. During this period, the AND gate 64 is opened and the latch 4 is opened.
The output data 9 (a count value corresponding to the contact capacitance component of the touch electrode T1 is now output) is written into the latch 65. In this case, the process of detecting the contact capacitance component of the touch electrode T is executed many times according to the rectangular wave signal A while the touch electrode T is in contact with the touch electrode T. Among the plurality of detection data, the maximum value is written to the latch 65.

Therefore, the contents of the latch 62 (the count value for the stray capacitance component of the touch electrode T1) and the contents of the latch 65 (the count value for the maximum contact capacitance component of the touch electrode T)
is sent to the display switching circuit 26 together with the contents of the counter 34 (electrode number "1" specifying the touch electrode T).

As a result, the display switching circuit 26 outputs the above-mentioned three types of data to the digital display section 4 in the check mode, so that the display contents of the digital display section 4 are, for example,
The result is as shown in FIG. That is, the digital display section 4
The electrode number rIJ is digitally displayed in the second digit, the count value "036" of the stray capacitance component in the third to fifth digits, and the count value "107" of the contact capacitance component in the sixth to eighth digits. As a result, it is possible to numerically and quantitatively test the state of disconnection of the touch electrodes T, ′□゛, the operating state of the touch input circuit, or the state of touch sensitivity, etc., making it possible to perform the test easily and reliably. becomes.

When the touch on the touch electrode T is released, the amount of delay of the signal B to be determined is the delay T with respect to the stray capacitance component. Therefore, the output of the e>ε detection circuit 50 becomes "1" again, the output state of the 5R-FF 55 is inverted (see FIG. 7), and as a result, the one-shot circuit 5
6 is output as a signal e after a predetermined time (7th
(see figure). As a result, the counter 3 that counts the electrode number
The value of 4 is increased by +1 to become "2", so the touch electrode T,
is sensed next. At the same time, the contents of latches 62 and 65 are cleared.

As a result of such operations being executed sequentially according to the contents of the counter 34, test data for the touch electrodes T1 to T are sequentially displayed digitally in the check mode.

By the way, the operation of detecting the presence or absence of a touch input in the watch mode and the computer mode is the same as the detection operation in the above-mentioned check mode, so the details are omitted, but in this case, the decoder 31 Since the data W is input to the , the sensing operation of the touch electrode is performed according to the data W.

Next, the operation of the character recognition control giS20 is explained in FIGS.
This will be briefly explained with reference to FIG. Prior to explaining this character recognition operation, the XY coordinate system set for nine touch electrodes arranged in a 3×3 matrix will be explained with reference to FIG. This XY coordinate system is
Touch electrode T.

11X11 = 121 coordinate positions are set in the coordinate plane connecting the center positions of all the touch electrodes except for . And its XY coordinate position is (0, 0), (0%
1) It is expressed as...

Character pattern data such as numbers and symbols are input using the 121 coordinate digits thus set. That is, when inputting character pattern data, numbers and the like may be input by hand within the coordinate plane.

The character recognition process is executed according to the flow shown in FIG. In other words, when entering character recognition processing,
The initialization process in step S1 is first executed, and the Fl and F2 registers IC "1" provided in the RAM (see FIG. 12) in the character recognition control unit 2o are respectively set, and the contents of the counter Z are cleared. Ru. In this case, the B register is set to 0" at the beginning of one stroke and 1" at the end, and the F2 register is set to 10" at the beginning of one stroke and 6f at the end.Furthermore, Counter Zll''i counts the number of strokes of one character. Next, the presence or absence of a touch input is determined (step s), and if there is no touch input yet, the process moves to step s0 and the contents of the F register are changed to rO
It is determined whether it is J or not, but since it is Fi″1′ at first, step S is performed.

Return to and wait until there is a touch input.

Then, if there is a touch input, the process proceeds to step s3,
F: It is determined whether the contents of the register are "1" or not. Since Fi" is initially 1'°, the process proceeds to step s4, and 0" is set in the F register to indicate the start of writing one character. Next, step S.

In this case, it is determined whether the contents of the F2 register are "1" or not, but since it is initially "1", an increment process is performed to increment the contents of the stroke number counter Z by 1.As a result, one stroke of one character When , the content of the stroke number counter Z becomes "1", which is the value of the first stroke. Next, after the contents of the F register are cleared (step S7), the process proceeds to step s8, where coordinate input processing is executed.

This coordinate input process is executed according to the flow shown in FIG. That is, first, the count value of the contact capacitance component for each touch electrode is read from the touch input unit 19 (step S), and the touch electrode TM with the maximum capacitance is
Set ax (step S,). In other words, if you touch multiple touch electrodes at the same time, the maximum capacity touch electrode'
I'M aX is recognized. Then, select the upper, lower, right, and left touch electrodes around the touch electrode TM a x with the largest capacity, and select the touch electrode with the largest capacity '
The coordinates at the center of the contact area are calculated from the count value for the contact capacitance component between I'Max and the surrounding touch electrodes (step Ss). In the next step S4, it is checked whether the coordinates have changed, in other words, whether the finger is stopped at one place and its center coordinates have not changed. , the process moves on to the next step in the flow shown in FIG. 10. If the center coordinates have changed, the process proceeds to the next step S, and the first center coordinates of the first stroke determined as described above are changed to the first center coordinates of the first stroke. The data is sent to the RAM shown in FIG. 12 and stored therein. RAM in FIG. 12 includes a coordinate storage unit M for stroke 1, a coordinate storage unit gISM for N stroke 2, . . .
Each memory unit M, , M2, river, etc. has a maximum of two center coordinates written in its addresses 1 to n. In addition, $1
In the RAM 211, T is a register in which time data is stored, and TM is a register in which timer time is stored.

With the above, the first stroke of the input character pattern
Once the th center coordinates have been written into the RAM of FIG. 12, the process returns to step S of FIG.

Therefore, during input of one stroke, step S
3. Since the determination in step S is NO, steps S, , S, , S, , and S8 are executed, respectively, and as a result, each center coordinate of one stroke is sequentially written to the RAM shown in FIG. It goes down.

- to finish writing one stroke of a character and start writing the next stroke, or to finish writing one stroke of a character and start writing the first stroke of the next input character; When you release your finger, step S
This is detected in , and the process proceeds to step S, but now the contents of register F are 0'', so the next step SI
Proceeding to step O, it is determined whether the contents of the F2 register are 0'' or not.In this case, the contents of the F2 register are also '0'', so the process proceeds to step 811, where the contents of the 1M register are cleared and the time is measured. Start the operation. Next, after setting F in the step Sat and 1″ in the register,
Return to step S.

As a result, the judgment in the next step SIO is NO, and the process proceeds to steps S, , Ic, and the time interval from the end of writing one stroke to the start of writing the second stroke is detected by reading the contents of the 1M register. However, it is determined whether this time interval is longer than a certain time. Here, if the time interval is smaller than a certain time, it is determined that the writing of one stroke has ended, and if it is larger, it is determined that the writing of one character has ended, that is, the printing of the character.

If the above-mentioned time interval is smaller than a fixed time, the process returns to step S, and enters a standby state where steps S2, Sg, and 816%81B are repeated as soon as the next stroke of the same character is input. is judged to be large,
Proceeding to step S, 4, a character recognition process to be described later is executed, and the characters recognized thereby are sent to the clock section 23 in the clock mode, and to the computer section 25 in the computer mode. It will be done.

Next, the character recognition process in step 814 will be explained with reference to FIGS. 13 to 16. Figure 16 shows the situation when the number ``2'' with a stroke number of ``1'' is input by touch.As shown in Figure 13 (3), when the character pattern ``2'' is input, the above-mentioned As shown in FIG. 12, the coordinate data is sequentially written into the RAMK shown in FIG. After inputting the character pattern "2", when the finger leaves the touch electrode, the stroke length is calculated from the coordinate data written in the RAM, and then, as shown in Figure 13 (■), the stroke length is 6 etc. divided. As shown in Figure 13 (0), each equally divided point is approximated by a straight line from the starting point side to the ending point side, and the vector (0 to 7 of 8
The vectors of each part are determined according to the type (type), and a vector sequence is calculated.

Then, the vector sequence obtained in this way is R, OM
2' is compared with the standard vector string in 1, the most similar character pattern is extracted, and the character pattern is output from the character recognition control unit 20.

Here, in FIGS. 15 and 16, the stroke is 1, respectively.
．． 2 shows the standard vector string of each character pattern, and the ROM
It is stored in 21. In this case, in this embodiment, the characters and turns that can be input are limited to numbers and four arithmetic functions, so it is sufficient that the id No. 151 and the standard vector sequence shown in FIG. 16 are stored in the ROM 21. . In addition, in FIG. 15, "1" indicates "÷".

As described above, since this embodiment is applied to a character recognition device, it is not necessary to actually input a large number of character patterns by handwriting when inspecting the input section. This can be done by adding
The number of checks can be extremely reduced. Also,
Digital display of check data for individual touch electrodes allows quantitative testing.

However, the present invention is not limited to the above-described actual example, and can be modified and applied in various ways without departing from the scope of the present invention. For example, in the above embodiment, the touch electrodes are arranged in a 6 x 3 matrix, and the coordinate positions of 11 x 11-121 are input. may correspond to 1:1. Further, the type of input characters may be katakana, hiragana, kanji, etc., and furthermore, it does not have to be applied to a character recognition device. In addition, the display of the check data is not limited to digital display, but any display that can be displayed quantitatively may be used, and an alarm may be provided along with this display.

〔Effect of the invention〕

As described in detail above, the present invention provides a capacitive detection type touch switch device that performs switching by detecting changes in capacitive components when a human body is attached to a touch electrode.
Since the capacitance component of the touch electrode is displayed, it is possible to quantitatively inspect the state of disconnection of the touch electrode, the operating state of the touch input circuit, the touch sensitivity, etc. This makes the inspection easier and easier. It can be done exactly 7 times.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with Fig. 1 showing the front part of an electronic wristwatch to which the invention is applied, Fig. 2 showing the relationship between touch electrodes and their electrode numbers, and Fig. 3. is a block diagram of the digital display section, FIG. 4 is a block circuit diagram of the entire electronic wristwatch, FIG. 5 is a detailed circuit diagram of the touch input section, and FIG. 6 is a timing diagram to explain the operation in set mode. 7 is a timing chart for explaining the operation in check mode, FIG. 8 is a display M diagram in check mode, FIG. 9 is a diagram for explaining the XY coordinate system, and FIGS. FIG. 11 is a flowchart for explaining the operation of the character recognition control section, FIG. 12 is a configuration diagram of the RAM provided in the character recognition control section, and FIG. 13 (
2) to C) are diagrams showing the process of obtaining a vector sequence when the number "2" is input as a character pattern, and Figure 14 is a diagram showing the relationship between the numerical values and vectors that make up the standard vector sequence. , FIG. 15, and FIG. 16 are diagrams showing standard vector sequences of character patterns having stroke numbers rlj and r2j, respectively. 3 (To "To")...Touch electrode, 4.
...Digital display section, 19...Touch input section. Patent applicant Casio Computer Co., Ltd. Figure 8 40L Figure 9 Figure 11 Figure 12 Figure 14 Figure 13 Figure 15 Figure 16

Claims (1)

[Claims] A touch switch device of a capacitive detection type that performs switching by detecting the amount of change in a capacitance component when a human body touches a touch electrode, characterized in that the capacitance component of the touch electrode is displayed.