JPH0822355A - Signal transmission system of coordinate input device - Google Patents

Abstract

PURPOSE:To transmit coordinate information that a coordinate detection pen detects and additional information other than coordinate information that the pen has on a time-division basis through the same signal line or by radio of the same channel. CONSTITUTION:A tablet is a grating in nXm units consisting of Y-directionally arranged common electrodes 4 and X-directionally arranged segment electrodes 5. The electrodes 4 and 5 are driven by driving circuits 2 and 3 to turn ON and OFF. A control circuit 1 performs driving timing control over the driving circuits 2 and 3, a wired type detection pen 6, and a cordless type detection pen 7. The main body of a system which uses the cordless type pen 7 is provided with a transmission and reception unit 8 for having a communication with the pen 7. Signals sent from the pens 6 and 7 directly or through the transmission and reception unit 8 are separated and converted by a detecting circuit 9 into coordinate data and various additional information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal transmission system of a coordinate input device, and more particularly, to the same signal as the coordinate information detected by the coordinate detection pen and the additional information other than the coordinate information possessed by the detection pen. The present invention relates to a signal transmission system of a coordinate input device which transmits in a time-division manner to a line or a radio of the same channel. For example, the present invention is applied to all coordinate detection devices and information processing devices to which the coordinate detection device is applied.

[0002]

2. Description of the Related Art As a known document describing a conventional coordinate input device, for example, there is JP-A-5-80921. In this publication, in order to prevent malfunction caused by noise on the detection pen, the mode detection circuit receives an electrostatic induction voltage induced in the detection pen by polarity reversal of the image display voltage during the display period, The electrostatic induction voltage is compared with a preset reference voltage, and when the electrostatic induction voltage is higher than the reference voltage, it is determined to be the detection mode in which coordinate detection should be performed. On the other hand, when the electrostatic induction voltage is smaller than the reference voltage, it is determined as the non-detection mode in which the coordinate detection is not performed, and the mode signal indicating the determination result is output. The coordinate output selection circuit outputs the coordinates as they are when the mode signal indicates the detection mode. On the other hand, when the mode signal indicates the non-detection mode, the output of coordinates is stopped. That is, a method of transmitting the coordinate signal and the switch ON / OFF signal by independent signal lines is shown.

In Japanese Patent Laid-Open No. 1-254975, a document placing table having coordinate signal generating means on the document placing surface and a document placing surface are used for designating contact with an arbitrary point on the document placing surface. A coordinate designating pen that generates a timing signal for determining a coordinate signal when it comes into contact with the placement surface, and a plurality of color designating signals that are installed in the pen body of the coordinate designating pen and that generate a color designating signal for designating a print color. And a color designation switch. That is, a method is shown in which the coordinate signal is output only when the pen down switch is turned on, that is, when the pen tip is pressed against the tablet.

FIG. 11 is an overall configuration diagram of a conventional coordinate input device, in which the system described in the above publication is shown in a form similar to that of the embodiment of the present invention. 3 in the figure
1 is a control circuit, 32 is a common drive circuit, 33 is a segment drive circuit, 34 is a common electrode (Y1 to Ym), 35 is a segment electrode (X1 to Xn), 36 is a pen (wired),
37 is a pen (cordless), 38 is a receiving unit, 39
Is a coordinate detection circuit.

The tablet is a grid of n × m units composed of a common electrode 34 arranged in the Y direction and a segment electrode 5 arranged in the X direction. These electrodes are driven ON or OFF by drive circuits 32 and 33, respectively. The control circuit 31 controls the timing of each drive circuit. The detection pens include a wired pen 36 connected to the main body with a cable and a cordless pen 37 that transmits and receives data by wireless or infrared rays. In a system using a cordless pen, a receiving unit 38 for receiving a signal from the pen is provided in the system body. A signal transmitted directly from the pen or via the receiving unit 38 is converted into coordinate data by the coordinate detection circuit 39.

FIG. 12 is an operation timing chart of the coordinate input device shown in FIG. One cycle of the operation of the system (one frame in the notation in the figure) consists of a Y coordinate detection period and an X coordinate detection period. The control circuit 31 outputs a signal YDET (FIG. 12A) defining the Y coordinate detection period and a signal XDET (FIG. 12B) defining the X coordinate detection period to control the operation of the system. In the Y coordinate detection period, the Y coordinate electrodes Y1 to Ym are sequentially turned on, and in the X coordinate detection period, the X coordinate electrodes X1 to Xn are sequentially turned on (FIG. 12).
(C)). On the other hand, the detection unit of the pen outputs a signal when the electrode closest to the pen tip is turned on (see FIG. 12).
(D)) The position of the pen tip on the tablet can be identified from the timing of the signal from the pen. Specifically, the time from the rise of YDET to the rise of the pen signal represents the Y coordinate, and the time from the rise of XDET to the rise of the pen signal represents the X coordinate.

If the pen signal never becomes H while YDET is at H level, it can be determined that the pen tip is away from the tablet. The same is true for XDET. The conversion of the output signal of the pen into the coordinate information is processed by the coordinate detection circuit 39. The coordinate detection circuit 39 obtains the Y coordinate from the time from the rise of YDET to the rise of the pen signal and the X coordinate from the time from the rise of XDET to the rise of the pen signal.

FIG. 13 is a diagram showing an example of a detection pen. In the figure, 41 is a pen tip (detection section), 42 is a comparator, 4
3 is a first switch (pen down switch), 44 is a second switch (push switch), and 45 is a pen connection cable.

The tip 41 of the pen is the electrode 3 of the tablet.
Capacitively coupled to 4,35. The comparator 42 detects the peak of the dielectric voltage at the tip of the pen based on the scanning signal of the tablet electrode, and outputs the logic H / L level (H at peak detection). The pen is provided with a pen down switch 43 for detecting the pressing of the tip of the pen, and a push switch 44 which is operated by the user and used for setting or the like by an application. These pen switches are connected to independent signal lines. Therefore, the connection cable 45 includes a coordinate output signal line, a pen down switch signal line, a push switch signal line, and two power supply lines, for a total of five. If push switches are added, it is necessary to increase the number of wires.

FIG. 14 is a diagram showing an example of a conventional cordless detection pen. In the figure, 46 is a battery, 4
Reference numeral 7 is a power supply circuit, 48 is a transmission unit, 49 is a power switch, 50 is a low battery indicator, and other parts having the same functions as those in FIG. 13 are denoted by the same reference numerals.

The pen and the main body are not connected by a cable, but a transmission unit 48 with a built-in pen is used by radio or infrared rays.
Is transmitted from the tablet to the receiving unit 38 of the tablet body. This transmitting unit 48 is a pen down switch 43.
The coordinate signal is output only when is ON. 12
If the pen down switch 43 is OFF in the first frame and ON in the second frame as shown in (e), the output signal of the pen is as shown in FIG. 12 (f). No signal appears, and the coordinate signal is output in the second frame. In this example, no push switch is provided, and therefore, the transmission channel is only one piece of coordinate information. In the cordless system, the circuit power is not supplied from the main body, so the battery 46 and power circuit
7, and a power switch 49 is built in. The power supply circuit 47 supplies a stabilized power supply voltage to the circuit, detects the voltage drop of the battery 46, and lights the low battery indicator 50.

[0012]

As described above, in the first conventional method, it is necessary to add a dedicated signal line for transmitting information other than coordinate data. Therefore, in a system in which a large number of pen switches are provided or a large amount of additional information is transmitted, the number of cores of the pen connection cord increases, which leads to an increase in cost. There is also a problem that the pen is difficult to operate because the connection cord becomes thick. Also, as shown in the second conventional method, there is a method in which the coordinate detection signal is not output when the pen switch is OFF, but this method can reduce the signal line of one switch at most.

As a function selecting means, as shown in FIG. 15, there is known a method of pointing to an icon on a display screen without using a pen switch. However, in this method, the icon display occupies a part of the screen, and the effective work area of the screen is narrowed. Further, in order to select a function, a complicated operation of once releasing the pen from the work area, touching the icon, and returning the pen to the work area is required. Regarding the low battery warning system of the cordless system pen, in the above-mentioned conventional example, the pen is provided with an indicator so that it is not necessary to add a transmission channel independent from the coordinate signal transmission. However, the user's attention while operating the tablet is directed to the display screen and the tablet, and the indicator display of the pen may be overlooked.

The present invention has been made in view of the above circumstances, and the coordinate information detected by the coordinate detection pen and the additional information other than the coordinate information possessed by the detection pen are wirelessly transmitted through the same signal line or the same channel. It is an object of the present invention to provide a signal transmission system of a coordinate input device that transmits time-divisionally.

[0015]

In order to achieve the above object, the present invention provides: (1) a coordinate input device for detecting a scanning signal of a tablet by a detection pen and detecting the position of the detection pen. In addition to the coordinate information detected by the pen, information indicating the status of the pen switch, which is the switch built in the detection pen, is sent on the same signal line (in the case of a cordless pen, one channel wireless, infrared, etc.) To send to the system body in a divided manner to let the system know the state of the pen, function settings, etc. from the state of the switches.
Alternatively, (2) in the display device / coordinate input device that detects the scanning signal of the liquid crystal display device by the detection pen and detects the position of the detection pen, in addition to the coordinate information detected by the detection pen, the state of the pen switch On the same signal line (in the case of a cordless pen, 1 channel wireless,
Time-divisionally transmitted to the system main body (by infrared rays or the like), coordinate information is transmitted during the coordinate detection period, and status information of the pen switch is transmitted during the display period, and further (3) to the detection pen. By setting a unique ID code and transmitting the ID code by adding the coordinate information to the state of the pen switch by the signal transmission method described in (1) or (2) above,
Identifying which one of a plurality of pens has been used, and (4) a coordinate detection device using a cordless pen with a built-in battery, wherein
Or, by the signal transmission method described in (2), information about the capacity of the built-in battery of the pen (voltage, low battery status, etc.)
Is transmitted to the system.

[0016]

The signal transmission method of the coordinate input device of the present invention is as follows: (1) The operation cycle of the tablet is divided into a coordinate detection period and an additional information transmission period, and the same output signal line is used for coordinate data output in the former and the latter. Is used to output additional information such as the state of the pen switch. This eliminates the need for an independent signal line for each additional information. (2) The display period of the operation cycle of the display device coordinate input device is assigned to the additional information transmission period, and the additional information is output during the period in which the system is displaying. It is possible to avoid the problems of deterioration of display contrast and deterioration of followability of coordinate detection, which may occur when the operation cycle is extended to add the additional information transmission period. (3) By transmitting an ID code unique to the pen as the additional information in addition to the state of the pen switch, the system can identify which of a plurality of prepared pens has been used. (4) By transmitting the voltage of the pen built-in battery as the additional information and making the system grasp the battery voltage of the pen, it is possible to provide a coping means such as displaying a low battery warning on the screen.

[0017]

Embodiments will be described below with reference to the drawings. FIG. 1 is a configuration diagram for explaining an embodiment of a coordinate input device according to the present invention, and is a diagram showing an example of an electrostatic induction tablet. In the figure, 1 is a control circuit, 2 is a common drive circuit, 3 is a segment drive circuit, 4 is a common electrode (Y1
To Ym), 5 are segment electrodes (X1 to Xn), 6 is a pen (wired), 7 is a pen (cordless), 8 is a transmission / reception unit, and 9 is a detection circuit.

The tablet is a grid of n × m units composed of a common electrode 4 arranged in the Y direction and a segment electrode 5 arranged in the X direction (the X side in the drawing is a segment,
The Y side is described as common because this is because the common code notation is used for convenience of illustration of the LCD tablet of the second embodiment). These electrodes are turned on or off by the common drive circuit 2 and the segment drive circuit 3, respectively.
Driven by FF.

The control circuit 1 controls the drive timing of the drive circuits 2 and 3 and the detection pens 6 and 7. There are two types of detection pens: a wire-type detection pen 6 connected to the main body with a cable, and a cordless detection pen 7 that sends and receives data wirelessly or by infrared rays. Usually, either one of these methods is used. are doing. However, there may be a system in which a plurality of pens can be used. In a system using a cordless pen, a transmission / reception unit 8 for communicating with the pen is provided in the system body. Directly from the detection pen,
Alternatively, the signal transmitted via the transmission / reception unit 8 is separated / converted into coordinate data and various additional information by the detection circuit 9.

FIG. 2 is an operation timing chart of the coordinate input device shown in FIG. One cycle of the operation of the system (one frame in the notation in the figure) is composed of three periods of a Y coordinate detection period, an X coordinate detection period, and an additional information transmission period. The control circuit 1 uses the signal YDET (see FIG. 2) that defines the Y coordinate detection period.
(B)), signal XDET defining the X coordinate detection period
(C) and a signal DET that defines the entire coordinate detection period
(FIG. 2A) is output to control the operation of the system.

During the Y coordinate detection period, the Y coordinate electrodes Y1 to Y are provided.
m is the X coordinate detection period, the electrodes X1 to Xn of the X coordinate are sequentially turned on (FIG. 2 (d)). On the other hand, since the detection unit of the pen outputs a signal when the electrode closest to the pen tip is turned on (FIG. 2 (e)), the position of the pen tip on the tablet is determined from the timing of the signal from the pen. Can be identified. Specifically, the time from the rising of YDET to the rising of the pen signal represents the Y coordinate, and the time from the rising of XDET to the rising of the pen signal represents the X coordinate.

If the pen signal never reaches H while YDET is at H level, it can be determined that the pen tip is away from the tablet. The same is true for XDET. The additional information transmission period is a period for receiving the additional information from the pen, and the pen outputs the additional information as shown in FIGS. 2F and 3 during this period.
Note that FIG. 3 is an enlarged view of A in FIG.

The detection of the coordinate information and the additional information from the output signal of the pen is processed by the detection circuit 9. The detection circuit 9
Obtains the Y coordinate from the time from the rise of YDET to the rise of the pen signal and the X coordinate from the time from the rise of XDET to the rise of the pen signal (the detection circuit has an internal clock for measuring the time). Then, the pen signal from the trailing edge of XDET is interpreted as additional information (the detection circuit also separates each bit of the additional information transmitted serially, so that the frequency of the additional information transfer clock of the pen is the same). Have two internal clocks).

FIG. 4 is a diagram showing a first embodiment of the detection pen, and is a diagram showing an example of a wired detection pen. In the figure, 1
1 is a pen tip (detection unit), 12 is a comparator, 13 is a first switch (pen down switch: switch), 1
4 is a second switch (switch), 15 is a third switch (switch), 16 is a fourth switch (switch), 17 is a fifth switch (switch), 18 is a sixth switch (rotary switch: Switch), 19
Is an output selection circuit, 20 is an ID code generation circuit, and 21 is a pen connection cable and connector. In addition, switch 1
4 to 17 are push switches.

The tip 11 of the pen is the electrode 4 of the tablet.
Capacitively coupled with 5. The comparator 12 detects the peak of the dielectric voltage at the tip of the pen according to the scanning signal of the tablet electrode, and outputs the logic H / L level (H at peak detection). The pen has a pen down switch 13 for detecting the pressing of the tip of the pen, push switches 14 to 17 operated by the user, and a rotary switch 18 (these applications are determined at the application level,
There is no particular limitation in this embodiment. It is conceivable that the color and thickness of the drawn line may be selected as the application of the switch, and the writing / erasing mode may be switched.), And an ID code generation circuit 20 for outputting the pen ID code is provided.

These pieces of information, that is, the coordinate detection signal (comparator output), the state of each push switch and the rotary switch, and the ID code are selected by the output selection circuit 19 and sequentially output. The connection cable 21 is composed of four lines. That is, an output selection signal line, an output signal line, and two power supply lines. The cable is connected to a connector, and the pen can be easily attached / detached / replaced.

FIG. 5 is a detailed diagram of the output selection circuit in FIG. 4, in which 22 is a counter, 23 is an oscillator (oscillator), 24 is a multiplexer (A), and 25 is a multiplexer (B). This output selection circuit does not output a signal when the pen down switch 13 is OFF. When the pen down switch is ON, the following operation is performed. When the input selection signal SEL (the DET signal from the control circuit is connected) is L, that is, the multiplexer 24 selects the signal from the pen tip / comparator (coordinate detection unit) during the coordinate detection period. When SEL (DET) is H, that is, during the additional information transmission period, the multiplexer 24 selects the output from the multiplexer 25. The input selection of the multiplexer 25 is determined by the counter 22.

The counter 22 is in the reset state while SEL is L, and is counted up by the oscillator 23 while SEL is H. The inputs of the multiplexer 24 are the states of the push switches 14 to 17 for D1 to D4, the state of the rotary switch 18 to D5 to D7 (there are eight contacts and are decoded into 3 bits), and the states of D8 to D1.
Since the output of the ID code generation circuit 20 is input to 0, this information is output in the sequence of FIG. 3 during this period. However, in this embodiment, the battery voltage information is unused. When SEL becomes H, the output of the multiplexer 24 is switched to the signal of the coordinate detecting section again, and the output selection counter of the multiplexer 25 is reset.

As a result of the above operation, the output of the output selection circuit 19 outputs the coordinate detection signal during the coordinate detection period and the state of each pen switch during the additional information detection period as shown in FIG. 2 (d). ID code generation circuit 20 in the present embodiment
Is a three-switch or eight-contact rotary switch, and generates one of the codes 0 to 7 depending on the switch setting in advance.

FIG. 6 is a diagram showing a second embodiment of the detection pen, and is a diagram showing an example of a cordless system. In the figure, 26 is a battery, 27 is a power supply circuit, 28 is a transmission / reception unit,
Reference numeral 29 is a power switch, and other parts having the same functions as those in FIG. 4 are designated by the same reference numerals.

The pen and the main body are not connected to each other by a cable, and the pen built-in transmission / reception unit 2 is used by radio or infrared rays.
8 and the transmitting / receiving unit 8 of the tablet body are communicating with each other. Since the circuit power is not supplied from the main unit,
A battery 26, a power supply circuit 27, and a power switch 29 are built in the pen itself. The power supply circuit 27 supplies a stabilized power supply voltage to the circuit, and the battery 2
The voltage of 6 is detected and transmitted to D11 to D13 of the output selection circuit 19 as 3-bit data. Therefore, the format of the additional information is as shown in FIG. In this embodiment, unlike the first embodiment, the ID code setting switch is not provided, and the setting can be performed by a specific operation of another switch.

FIG. 7 is a detailed view of the ID code generating circuit in FIG. 6, which is a battery-backed latch circuit. A value to be registered as an ID code is set in the rotary switch 18, and the push switches 15 to 17 are set.
When all are pressed at the same time, the setting of the rotary switch 18 is latched as an ID code. This value is always backed up by the pen's built-in battery.

FIG. 8 is a block diagram for explaining another embodiment of the coordinate input device according to the present invention, which is a liquid crystal display device (LC).
FIG. 9D is a diagram showing an example of a dual-purpose electrostatic induction tablet. In the figure, 10 is a liquid crystal panel, and other parts having the same functions as those in FIG. The electrodes 4 and 5 both detect coordinates and drive the liquid crystal panel 10. The control circuit 1 generates display timing as well as coordinate detection timing, and transfers data in a video RAM (not shown) to the segment drive circuit 3 during the display period. Although not shown in the figure, the polarities of signals to the electrodes 4 and 5 are periodically inverted to prevent electrolytic deterioration of the liquid crystal. In this embodiment, the same detection pen as in the first embodiment is used.

9 and 10 are operation timing charts of the coordinate input device shown in FIG. As shown in FIG. 9, one cycle of the operation of the system (one frame in the notation in the figure) consists of a display period and a coordinate detection period. The display period also serves as an additional information transmission period, and the coordinate detection period is divided into a Y coordinate detection period and an X coordinate detection period. The control circuit 1 uses the signal YDET (FIG. 10B) that defines the Y coordinate detection period,
A signal XDET that defines the X coordinate detection period (see FIG.
(C)), and a signal DET that defines the entire coordinate detection period
(FIG. 10A) is output to control the operation of the system.

The control circuit 1 controls the common electrode Y during the display period.
1 to Ym are sequentially scanned, and the segment electrodes X1 to Xn are sequentially scanned while each common electrode is ON. However, in the segment, only the electrodes corresponding to the lit pixels of the liquid crystal are turned on based on the data in the video RAM. The operation timing in the coordinate detection period is the same as in the first embodiment.

The output signal of the pen is the DET signal (see FIG. 10).
When (a)) is H, it is switched to the coordinate signal, and when it is L, it is switched to the additional information (FIG. 10 (f)). The detection circuit 9 obtains the Y coordinate from the time from the rise of YDET to the rise of the pen signal, and the X coordinate from the time from the rise of XDET to the rise of the pen signal. Also, the pen signal from the falling edge of DET is interpreted as additional information. Additional information is DE
It is repeatedly output during the display period when T is L,
The detection circuit adopts only the first one. In addition, the scanning signal of the tablet electrode (FIG. 10 (d)) is actually
In order to prevent electrolytic deterioration of the liquid crystal due to application of direct current, the polarity is periodically inverted at least during the display period.
Then, the mechanism for this is omitted.

As described above, in the signal transmission system of the coordinate input device of the present invention, in order to transmit the state of the switch provided on the pen without increasing the number of signal lines, these pieces of information are transmitted to one signal line. We adopted the method of transmitting in divided. A period for detecting the coordinate pointed by the pen and transmitting information indicating the coordinate and a period for transmitting information about the ON / OFF state of the pen switch are provided, and these periods are alternately repeated. Since the operation cycle of the display device / coordinate input device has a display period and a coordinate detection period, the display period is assigned to the transmission period in the pen switch state.

A plurality of pen switches can be provided, and the state of each switch is sequentially transmitted in synchronization with the internal clock of the pen during the transmission period of the switch state. In addition to the state of the switch, the pen can be provided with various additional information, which can also be transmitted during this period. In the embodiment of the present invention, an ID is assigned to each of the pens so that each of the pens can be identified.
Code information is provided.

When the detection pen is of the cordless type,
The pen requires its own power source. The low battery warning of the pen's built-in battery is less likely to be overlooked by the user when displayed on the display screen rather than the pen itself. In the present invention, various additional information can be transmitted in addition to the state of the switch. Therefore, information about the battery voltage is transmitted to the system itself, enabling a low battery warning on the display screen.

[0040]

As is apparent from the above description, the present invention has the following effects. (1) Effect corresponding to claim 1: By transmitting a large amount of additional information other than coordinate information from the detection pen to the main body of the coordinate input device, the added value of the coordinate input device can be increased and a signal can be provided. It is possible to avoid problems caused by the increase in the number. The merit of transmitting a large amount of additional information is that it is possible to mount a large number of switches that can be applied to various applications, and its applications include, for example, changing the color and thickness of drawn lines, switching between entry / erasure modes, etc. Can be considered. Hand operation with a pen switch can take a larger work screen than the icon selection method,
In addition, the complicated work of moving the pen to the icon area when selecting a function and returning to the work area after selecting the icon is not necessary. In addition to the pen switch, the pen can have various sources of information, which can be transmitted to the system. The implementation of claims 2 and 3 is an example.
The problems solved by avoiding the increase in the number of signals are:
In the case of the wired system, the number of cores of the pen connection cable can be small, so that the cost can be reduced, and the cable does not have to be thick, so that the operability is not adversely affected. Also in the case of the cordless method, the number of transmission channels is small, so that the cost can be reduced. (2) Effect corresponding to claim 2: The same effect as claim 1 can be obtained. Further, since the scanning period does not become long due to the transmission of the additional information, it is possible to avoid problems such as a decrease in display contrast and poor followability of coordinate detection. (3) Effect corresponding to claim 3: A means for identifying the owner of a pen is provided by the ID code of the pen. Each system user has his own pen, and the user connects his own pen to the system and uses it. The system can identify the owner of the pen by using the ID code of the pen used, and provide a service according to each user. For example, the parallax data of the user registered in the system is called and the parallax is automatically corrected. This allows
There is no need to redo parallax correction each time the system user changes. Further, it is possible to give different functions to each of the plurality of pens. This is particularly suitable for cordless pens. The system identifies which pen was used by the ID code, and switches the color and thickness, and whether to write or erase, depending on the pen used. As a result, it is possible to obtain an operation feeling as if a plurality of pens having different pen thicknesses and colors are used, and in some cases, better operability can be expected as compared with the function selection method using the pen switch. (4) Effect corresponding to solving means 4: A warning of the battery consumption of the detection pen can be displayed on the display screen. This method is less likely to miss a warning than the method in which an indicator is provided on the pen.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a coordinate input device according to the present invention.

FIG. 2 is an operation timing chart of the coordinate input device shown in FIG.

FIG. 3 is an enlarged view of a portion A in FIG. 2;

FIG. 4 is a diagram showing an embodiment of a wired detection pen according to the present invention.

5 is a detailed diagram of an output selection circuit in FIG.

FIG. 6 is a diagram showing another embodiment of the cordless system detection pen of the present invention.

7 is a detailed diagram of an ID code generation circuit in FIG.

FIG. 8 is a configuration diagram for explaining another embodiment of the coordinate input device according to the present invention.

9 is an operation timing chart (No. 1) of the coordinate input device shown in FIG.

10 is an operation timing chart (No. 2) of the coordinate input device shown in FIG.

FIG. 11 is a configuration diagram of a conventional coordinate input device.

12 is an operation timing chart of the coordinate input device shown in FIG.

FIG. 13 is a diagram showing a conventional wired type detection pen.

FIG. 14 is a diagram showing a conventional cordless detection pen.

FIG. 15 is a diagram showing an example of a screen display in the conventional icon selection method.

[Explanation of symbols]

1 ... Control circuit, 2 ... Common drive circuit, 3 ... Segment drive circuit, 4 ... Common electrodes (Y1 to Ym), 5 ... Segment electrodes (X1 to Xn), 6 ... Pen (wired), 7 ... Pen (cordless) , 8 ... Transceiver unit, 9 ... Detection circuit,
11 ... Pen tip (detection unit), 12 ... Comparator, 13 ...
1st switch (pen down switch), 14 ... 2nd switch, 15 ... 3rd switch, 16 ... 4th switch, 17 ... 5th switch, 18 ... 6th switch (rotary switch), 19 ... Output selection circuit, 20 ... ID code generation circuit, 21 ... Pen connection cable and connector.

Claims (3)

[Claims] 1. A coordinate input device for detecting a scanning signal of a tablet by a detection pen and detecting the position of the detection pen, in addition to coordinate information detected by the detection pen, switches incorporated in the detection pen. The coordinate input device characterized in that the information indicating the state of the pen switch is transmitted to the system main body in a time division manner on the same signal line, and the state of the pen and the function setting are notified to the system from the state of the switches. Signal transmission method. 2. In a display device / coordinate input device for detecting a scanning signal of a liquid crystal display device by a detection pen and detecting the position of the detection pen, in addition to the coordinate information detected by the detection pen, the state of a pen switch. Is transmitted to the system body in a time division manner on the same signal line, the coordinate information is transmitted during the coordinate detection period, and the state information of the pen switch is transmitted during the display period. Signal transmission method. 3. An ID code unique to the detection pen is set, coordinate information is added to the state of the pen switch by the signal transmission method according to claim 1 or 2, and the ID code is transmitted. A signal transmission method for a coordinate input device characterized by identifying which pen was used.