JP4622432B2 - Touch panel control unit - Google Patents

Description

  The present invention relates to a touch panel control unit. More particularly, the present invention relates to a touch panel control unit that can handle different driving methods in a touch panel that employs a resistive film method.

A touch panel is used as a personal interface of a computer system such as a POS system. There is a resistive film system as a driving system for this touch panel, and there are a 4-wire resistive film system and a 5-wire resistive film system. The driving method is selected according to the purpose and usage of the touch panel so that the characteristics are reflected.
Conventionally, a dedicated control unit has been prepared corresponding to the selected touch panel drive method.
For a technique related to this case, refer to Patent Document 1 and the like.
Japanese Patent Laid-Open No. 9-167047

If a dedicated control unit is prepared corresponding to the touch panel as in the prior art, the touch panel can be reliably functioned. However, as the types of touch panels increase, the types of control units also increase, so that it is expensive to design and create various control units.
Thus, the inventors have conducted intensive studies to drive and control touch panels with different driving methods using a single control unit.

As a result, the present inventors have conceived a touch panel control unit having the following configuration. Touch panel control capable of driving the connected touch panel regardless of which one of the first touch panel driven by the first driving method or the second touch panel driven by the second driving method is connected. A unit,
The first control circuit corresponding to the first driving method and the second control circuit corresponding to the second driving method constitute a switch unit of the first control circuit and the second control circuit. A control circuit unit that shares and includes a switch unit composed of transistors ;
A connector capable of connecting the first touch panel or the second touch panel to the control circuit unit ;
Operating the transistors in a predetermined combination and detecting a voltage level of a specific panel voltage detection terminal signal synchronized with the transistor operation connected to an input terminal of an A / D converter connected to the control circuit unit; Accordingly, a driving method specifying unit driving method of a touch panel connected to the connector is identified whether the second driving mode or a first driving mode,
A first selection unit for outputting a control signal based on a driving mode that has been specified by the driving scheme specifying unit selects one of said first control circuit the second control circuit,
Operating the transistors in a predetermined combination and detecting a voltage level of a specific panel voltage detection terminal signal synchronized with the transistor operation connected to an input terminal of an A / D converter connected to the control circuit unit; By the diagnostic unit for diagnosing whether the operation of the transistor constituting the switch unit that is not brought into a stopped state by the first selection unit ,
A touch panel control unit.

According to the touch panel control unit configured as described above, the driving method of the touch panel connected to the connector is specified without the need for user intervention by the driving method specifying unit, and connected to the connector based on the specifying result. A control circuit corresponding to the touch panel driving method is selected. The selected touch panel which is connected to more connector to the control circuit is controlled drive, the function is properly exerted.

Invention of the second aspect of the present invention is constructed as follows.
That is, the second aspect is that the touch panel control unit of the present invention is configured such that the first driving method is a four-wire resistive film method and the second driving method is a five-wire resistive film method. in the switch unit which is included in the circuit part, three of the four said switch unit associated with the voltage detection in the X direction and Y direction of the touch panel comprises a pair of transistors, one of the other one of the transistors from made, the first selecting unit, when driving method specified by the driving method specific portion of the first driving method, one of the stop state of the pair of transistors constituting the three switch units Thus, a control signal for selecting the first control circuit can be output .
According to the invention of a second aspect configured as this, that the first control circuit and share a switch portion of the second control circuit, which consists of more separately transistor for a given switch As a result, the number of components of the control unit can be reduced and it can be provided at low cost.

According to a third aspect of the present invention, the touch panel control unit of the present invention includes a first parameter storage unit that stores a first parameter for executing the first drive method,
A second parameter storage unit for storing a second parameter for executing the second driving method;
A first program module storage unit for storing a first control program module for executing the first drive method;
A second program module storage unit for storing a second control program module for executing the second driving method;
A second selection unit for selecting a parameter based on the drive method specified by the drive method specifying circuit; and a third selection unit for selecting a control program module based on the drive method specified by the drive method specifying circuit;
Is further provided.
If the touch panel drive system is different, parameters and control program modules required for the drive may differ even if the control unit is shared. Therefore , according to the third aspect of the invention thus configured , optimum parameters and control program modules are prepared in advance for each driving method, and the optimum parameters and control are adapted to the specified driving method. A program is selected. Therefore, the touch panel is more appropriately controlled.
Furthermore, according to the fourth aspect, the touch panel control unit of the present invention cannot specify whether the drive method of the touch panel is the first drive method or the second drive method by the drive method specifying unit. In the case where the operation of the transistor is diagnosed by the diagnosis unit, an error signal can be transmitted.
According to the fourth aspect of the invention thus configured, since it is possible to provide an error signal transmission function based on the determination result of the drive method specifying unit or the diagnosis unit, the touch panel is very easy to use. A control unit can be provided.

The components of the present invention will be described below.
(Touch panel)
The resistive film drive type touch panel targeted by the present invention is roughly divided into a 4-wire resistive film system (hereinafter sometimes abbreviated as “4-wire type”) and a 5-wire resistive film system (hereinafter referred to as “ It may be abbreviated as “5-wire type”). The characteristic of the 4-wire resistive film type is the accuracy of the position accuracy. On the other hand, the characteristic of the 5-wire resistive film type is high durability. Therefore, the user can arbitrarily select the drive method in consideration of the characteristics. An 8-wire resistive film type is also known as one that uses the same operating principle as the 4-wire type. The 8-wire resistive film type is also treated in this specification as equivalent to the 4-wire type.

(Control circuit part)
The control circuit unit controls the operation of the touch panel.
In the touch panel, two resistive films are arranged at intervals in both the 4-wire type and the 5-wire type, and when the user touches the upper resistive film, the two resistive films come into contact with each other at the touched position. The touched position is specified from the voltage change at that time.
In order to specify the position, it is necessary to specify the coordinates of the resistance film in the X direction and the Y direction.
In the case of the 4-wire type, two switches are arranged in each direction to generate a voltage change (four in total), and one switch is arranged to detect the contact / non-contact of the two resistive films. Is done.

On the other hand, in the case of the 5-wire type, in order to cause a voltage change, of the four electrodes at the four corners of the lower resistive film, two switches are arranged on each of the three electrodes (total of six), and the remaining one electrode One switch is disposed on the screen. Furthermore, as with the 4-wire type, one switch is provided on the upper resistive film in order to detect contact / non-contact of the two resistive films.
One aspect of the present invention aims to provide an inexpensive control unit by sharing the switch section in the control circuit section.
Of course, the control unit for the 4-wire type and the control circuit unit for the 5-wire type are provided independently in the control unit, and only one of them is operated based on the result of specifying the drive method specifying unit described later. It is also included in the scope of the present invention.

(connector)
The connector has a plurality of pins and is connected to the touch panel. Predetermined pins of the connector are connected to the switch unit, and a signal is input in synchronization with the on / off of the switch unit, and application of voltage to the touch panel is controlled. The output of the touch panel is also input to the control unit via a predetermined pin of the connector and analyzed there.
The connector used in the present invention can be connected to either the first touch panel of the first driving system or the second touch panel of the second driving system.

(Drive system identification part)
The drive method specifying unit inputs a signal to the first pin of the connector to which any touch panel is connected, detects the output from the second pin, and specifies the drive method of the touch panel connected to the connector.
Signal input to the first pin of the connector can be performed by turning on and off a predetermined switch of the drive circuit unit as in the embodiment. In this embodiment, a high / low voltage is applied to the electrode of the resistance film as this signal.
By detecting the output signal from the second pin of the connector and analyzing it, the driving method of the touch panel connected to the connector can be specified. For example, when a predetermined switch is turned on and a voltage is applied from the first pin, the signal detected at the second pin is high on a 4-wire touch panel and low on a 5-wire touch panel. At this time, it can be seen that the driving method of the touch panel connected to the connector is specified by turning on the predetermined switch and detecting the output of the second pin.

  In addition to the above, the driving method of the touch panel can be specified. For example, when the resistance value of a certain part of the first touch panel and the second touch panel having different driving methods is different, the first touch panel and the second touch panel are distinguished from each other by measuring the resistance value of the part. Is possible. In this case, the voltage applied to the portion becomes an input signal to the first pin of the connector, and the drop voltage value becomes an output signal appearing at the second pin.

Hereinafter, the present invention will be described in detail based on examples.
FIG. 1 is a block diagram showing a configuration of a control unit 1 according to an embodiment of the present invention.
As shown in FIG. 1, the control unit 1 of the embodiment includes a control circuit unit 10, a connector 20, and a microcontroller 50.
One of a 4-wire resistive touch panel 24 and a 5-wire resistive touch panel 25 is selectively connected to the connector 20.

タッチパネル２４では最初にパネルの押下検出が行われる。そのため、表２の「パネル押下取り込み」のように制御信号線の各端子ＳＷ１〜ＳＷ０に接続されるスイッチユニットを制御し、Int1#の出力がＬｏのときタッチパネルに対する押下があったものとして入力点（図中矢印で示す）の座標検出を行う。 なお、前記スイッチユニットは、接続されている前記端子が「Hi」のときにオンとなり、「Lo」のときにオフとなる。
(Operation principle of the 4-wire touch panel 24)
First, the operation principle of the 4-wire touch panel 24 will be described with reference to FIG.
In FIG. 2, each terminal and its function are as shown in Table 1.
The notation “SW0 #” means the logical inversion of “SW0”, and “SW0 # = Lo” when “SW0 = Hi”. Hereinafter, the same notation is used in the text, tables, and drawings.

On the touch panel 24, the pressing of the panel is first detected. Therefore, the switch unit connected to each terminal SW1 to SW0 of the control signal line is controlled as shown in “Panel Press-Up” in Table 2, and it is assumed that the touch panel has been pressed when the output of Int1 # is Lo. Coordinate detection (indicated by an arrow in the figure) is performed. The switch unit is turned on when the connected terminal is “Hi” and turned off when it is “Lo”.

上側のタッチパネルは入力点において下側のタッチパネルに接触しているため、ＡＮ０（又はＡＮ１）へ距離Ｘ１に比例した電圧（Ｘ１／Ｘ）×Ｖｃｃが出力される。ここにおいて、Ｘは上側の抵抗膜におけるＸ方向両端に取り付けられた電極間距離である。
同様に入力点のＹ方向座標を検出するには、表２の「Ｙ方向データ取り込み」のように制御信号線の端子ＳＷ１〜ＳＷ０に接続されるスイッチを制御し、検出用端子ＡＮ２又はＡＮ３の出力を解析する。上側のタッチパネルは入力点において下側のタッチパネルに接触しているため、ＡＮ２（又はＡＮ３）へ距離Ｙ１に比例した電圧（Ｙ１／Ｙ）×Ｖｃｃが出力される。ここにおいて、Ｙは上側の抵抗膜におけるＹ方向両端に取り付けられた電極間距離である。 The input point coordinates are detected as follows.
To detect the X-direction coordinates of the input point, the switch unit connected to the terminals AW1 to SW0 of the control signal line is controlled as shown in “X-direction data capture” in Table 2, and the output of the detection terminal AN0 or AN1 is output. Is analyzed.

Since the upper touch panel is in contact with the lower touch panel at the input point, a voltage (X1 / X) × Vcc proportional to the distance X1 is output to AN0 (or AN1). Here, X is the distance between the electrodes attached to both ends of the upper resistive film in the X direction.
Similarly, in order to detect the Y-direction coordinate of the input point, the switches connected to the control signal line terminals SW1 to SW0 are controlled as shown in “Y-direction data capture” in Table 2, and the detection terminal AN2 or AN3 is controlled. Parse the output. Since the upper touch panel is in contact with the lower touch panel at the input point, a voltage (Y1 / Y) × Vcc proportional to the distance Y1 is output to AN2 (or AN3). Here, Y is the distance between the electrodes attached to both ends of the upper resistive film in the Y direction.

タッチパネル２５では最初にパネルの押下検出が行われる。そのため、表４の「パネル押下取り込み」のように制御信号線の各端子ＳＷ１〜ＳＷ０に接続されるスイッチユニットを制御し、ＡＮ１４及びＩＮＴ０＃の出力を解析してタッチパネルに対する押下判断を行う。押下があったとき、入力点（図中矢印で示す）の座標検出を行う。
(Operation principle of 5-wire touch panel)
Next, the operating principle of the 5-wire resistive touch panel 25 will be described with reference to FIG.
In FIG. 3, each terminal and its function are as shown in Table 3. Further, the symbol “Δ” in the figure has an inverter function and inverts and outputs an input signal.

On the touch panel 25, a panel pressing detection is first performed. Therefore, the switch unit connected to each of the terminals SW1 to SW0 of the control signal line is controlled as shown in “Panel push-in” in Table 4, and the output of AN14 and INT0 # is analyzed to determine whether or not the touch panel is pressed. When pressed, the coordinates of the input point (indicated by an arrow in the figure) are detected.

上側抵抗膜は入力点において下側抵抗膜に接触しているため、ＡＮ１４へ距離Ｘ１に比例した電圧（Ｘ１／Ｘ）×Ｖｃｃが出力される。ここにおいて、Ｘはフィルム側抵抗膜におけるＸ方向両端に取り付けられた電極間距離である。
同様に入力点のＹ方向座標を検出するには、表４の「Ｙ方向データ取り込み」のようにスイッチを制御し、検出用端子ＡＮ１４へ距離Ｙ１に比例した電圧（Ｙ１／Ｙ）×Ｖｃｃが出力される。ここにおいて、Ｙはフィルム側抵抗膜におけるＹ方向両端に取り付けられた電極間距離である。 The input point coordinates are detected as follows.
In order to detect the X-direction coordinates of the input point, the switch unit connected to each terminal SW1 to SW of the control signal line is controlled as shown in “X-direction data capture” in Table 4 and the output of the terminal AN14 is analyzed. .

Since the upper resistive film is in contact with the lower resistive film at the input point, a voltage (X1 / X) × Vcc proportional to the distance X1 is output to AN14. Here, X is a distance between electrodes attached to both ends in the X direction of the film side resistance film.
Similarly, in order to detect the Y-direction coordinate of the input point, the switch is controlled as in “Y-direction data capture” in Table 4, and the voltage (Y1 / Y) × Vcc proportional to the distance Y1 is applied to the detection terminal AN14. Is output. Here, Y is the distance between the electrodes attached to both ends in the Y direction of the film side resistance film.

The operation principle of the 5-wire touch panel 25 will be described in more detail with reference to FIGS.
As shown in FIG. 4, the 5-wire touch panel is composed of two resistive films, a glass screen, and a film, and the resistive films are attached to the inside of the glass screen and the film. Spacers with a uniform height are arranged at regular intervals between the glass screen with a resistive film and the resistive film, and are usually arranged so that the two resistive films do not contact each other. In a 5-wire touch panel, the upper resistive film is used as a voltage detection probe, and the lower resistive film is used to generate a partial pressure depending on the pressing point. Here, when the film side of the touch panel is pressed, the two resistance films come into contact with each other.

  FIG. 5 shows a position voltage detection method in the X direction. The resistive film has a uniform resistance value proportional to the distance. Therefore, when P1, P2, P3, and P4 are connected as shown in FIG. 5, current flows from the P1-P4 side to the P2-P3 side. In this state, since a voltage gradient is generated in the lower resistive film, the X-direction position voltage at an arbitrary point on the touch panel can be measured by a voltmeter or a device capable of measuring a voltage value.

  FIG. 6 shows a method of measuring the position voltage in the Y direction. When P1, P2, P3, and P4 are connected as shown in FIG. 6, current flows from the P3-P4 side to the P1-P2 side. In this state, the Y-direction position voltage at an arbitrary point on the touch panel can be measured with a voltmeter or a device capable of measuring a voltage value in the same manner as the X-direction position voltage.

  FIG. 7 shows a pressing detection method. When P1, P2, P3, and P4 are connected as shown in FIG. 7, the lower resistance film becomes Lo level. Furthermore, since the upper resistance film is connected to the power supply by a pull-up resistor, it becomes Hi level. In this state, when the upper resistive film is pressed, the upper resistive film changes from the Hi level to the Lo level. Therefore, the pressing can be detected by measuring the voltage value with a voltmeter or a device that can measure the voltage value. I can do it.

即ち、タッチパネルＸ方向及びＹ方向の電圧検出に関与する４つのスイッチユニットのうちの３つは一対のトランジスタが必要であるのに対し、残りの１つは１つのトランジスタのみから構成できる。 The control method of P1, P2, P3, and P4 can be summarized as shown in Table 5 based on the position voltage measurement method and the press detection method.

That is, three of the four switch units involved in the voltage detection in the touch panel X direction and Y direction require a pair of transistors, while the remaining one can be composed of only one transistor.

(Control circuit unit 10)
Details of the control circuit unit 10 are shown in FIG.
The control circuit unit 10 has five signal lines, and a switch unit is connected to each terminal (SW1 #, SW2, SW3 #, SW4, SW0 #). This switch unit corresponds to the switch of the 4-wire touch panel shown in FIG. 2 and the switch of the 5-wire touch panel shown in FIG. In other words, one transistor Q1 is provided as a switch unit to which the terminal SW0 # for detecting panel pressing is connected. The switch unit connected to the four terminals SW1 #, SW2, SW3 #, and SW4 for obtaining the coordinates of the pressed position is composed of two transistors Q2 and Q3, which are connected to SW1 #, and are connected to SW2. What consists of one transistor Q6, what is connected to SW3 # consists of two transistors Q4 and Q5, and what is connected to SW4 consists of two transistors Q7 and Q8. When this control circuit unit 10 is applied to a 5-wire system, as described in Table 5, one of the four switch units for obtaining the coordinates of the pressed position can be composed of one transistor.

When the control circuit unit 10 is applied to a 4-wire touch panel, each switch unit may be a single transistor. Therefore, the control circuit unit 10 is provided with a control line 5WireE1 # for stopping the transistor. For example, when 5WireE1 # is set to high, the transistor Q3, the transistor Q5, and the transistor Q7 are stopped. This state is shown in FIG. The control circuit section in the state of FIG. 9 drives a 4-wire touch panel, and the control circuit section in the state shown in FIG. 8 drives a 5-wire touch panel.
This 5WireE1 # is controlled by the switch selector 33 of the panel controller.

  The control circuit unit 10 includes six analog switches 11-16. The analog switches 11, 14, and 16 are used for a 4-wire touch panel, and the analog switches 12, 13, and 15 are used for a 5-wire touch panel. The analog switch is selected by a control signal on the control line 5WireE2 #. When the 5WireE2 # signal is high, the analog switches 11, 14 and 16 are operable, and when the signal is low, the analog switches 12, 13 and 15 are operable. The control line 5WireE2 # is controlled by the connector switch selector 34.

The analog switch 11 connects the input terminals AN0, AN1, AN2, and AN3 of the A / D converter to four pins (3pin, 2pin, 8pin, and 7pin) of the connector 20. These four pins are connected to four electrodes in the X and Y directions of the touch panel.
The analog switch 14 connects the control signals of the Y-direction lower electrode (YL), the X-direction right electrode (XR), and the X-direction left electrode (XL) to the three pins (1pin, 5pin, 6pin) of the connector, respectively.
The analog switch 16 connects the four pins of the connector to the Y-direction lower electrode (YL).

  The analog switch 12 connects the input terminal of the A / D converter to the electrodes P1, P2, P3, and P4 at the four corners of the lower resistance film described with reference to FIGS. The analog switch 13 connects the terminal AN14 to the 5-8 pin. The analog switch 15 inputs the control signals of the electrodes P3, P2, and P4 to the 2nd pin, 3rd pin, and 1st pin, respectively.

The control circuit unit 10 is connected to the panel controller 30 and the A / D converter 52 of the microcontroller 50.
The panel controller 30 includes a panel main control unit 31 as shown in FIG. The panel main control unit 31 controls the switch controller 32, the switch selection unit 33, the connector switch selection unit 34, the drive method identification unit 35, the diagnosis unit 36, the parameter selection unit 37, and the module selection unit 38.
The switch controller 32 applies a high or low signal to the five terminals SW0 # to SW4 based on a command from the panel main control unit 31. The switch selection unit 33 selects an operable transistor by controlling the voltage applied to the control line 5WireE1 # to be high or low. The connector switch selector 34 selects an operable analog switch by controlling the voltage applied to the control line 5WireE2 # to be high or low. The diagnosis unit 36 diagnoses the operation state of the transistor (switch unit) of the control circuit unit selected according to a predetermined rule. The drive method specifying unit 35 uses the diagnosis unit 36 to analyze the input signal obtained from a predetermined terminal of the A / D converter when a predetermined switch is operated, and specify the drive method of the touch panel coupled to the connector To do. The switch selection unit 33 and the connector switch selection unit 34 control the outputs of the control lines 5WireE1 # and 5WireE2 # according to the drive method specified by the drive method specifying unit 35. The parameter selection unit 37 selects parameters necessary for executing the drive method specified by the drive method specifying unit 35 from the parameter memory 41. The module selection unit 38 selects a control program module required from the module memory 37 when executing the drive method specified by the drive method specifying unit 35.
The panel main controller 31 is under the control of the main controller 51 of the microcontroller 50. A signal input to the A / D converter 52 is input to the panel controller 30 via the main controller 51. In addition, a host computer is connected to the main controller 51 via an input / output interface 53, and pressed position data is output.

The operation of the control unit 1 configured as described above will be described with reference to the flowchart of FIG.
When the touch panel is connected to the connector (step 1) and a predetermined check signal is input to the microcontroller 50, a signal is sent from the main controller 51 to the panel main controller 31. When the touch panel is connected to the connector, the check signal may be input to the microcontroller 50 from the connector.

In step 3, it is specified whether or not the connected touch panel is a 4-wire type. In this embodiment, the switch selection unit 33 sets the 5WireE1 # signal to high and the connector switch selection unit 34 sets the 5WireE2 # signal to high in response to a command from the panel main control unit 31, and the configuration of the control circuit unit 10 is shown in FIG. Shall. Thereafter, the switch controller 32 checks the operation of the switch to determine whether or not the connected touch panel is a 4-wire type. For example, as shown in Table 6, in order to check the switch unit connected to the terminal SW1 #, the switch unit connected to the terminal SW2 is turned on and the switch unit connected to the terminal SW0 # is turned off and connected to the terminal SW1 #. The switch unit is switched on and off, and the voltage level of the input terminal AN0 of the A / D converter at that time is checked. If the output of the terminal AN0 switches from high to low in synchronization with the on / off of the switch unit connected to the terminal SW1 #, the switch unit connected to the terminal SW1 # operates corresponding to the 4-wire touch panel. As a result, the connected touch panel is determined to be a four-wire touch panel, and the process proceeds to step 11.
Note that when a 5-wire touch panel is connected, AN0 is fixed high, so that it can be distinguished.

When the above output is not generated at the output terminal AN0, the process proceeds to step 5 to determine whether or not the touch panel is a 5-wire type.
In response to a command from the panel main control unit 31, the switch selection unit 33 sets the 5WireE1 # signal to low and the connector switch selection unit 34 sets the 5WireE2 # signal to low, and the configuration of the control circuit unit 10 is shown in FIG. Thereafter, the switch controller 32 checks the operation of the switch to determine whether the connected touch panel is a 5-wire type. For example, as shown in Table 7, in order to check the switch unit (transistors Q2, Q3) connected to the terminal SW1 #, the switch unit connected to the terminals SW2, SW3 # and SW4 is turned on and connected to the terminal SW0 #. The switch unit connected to the terminal SW1 # is switched on and off, and the output of the terminal AN0 at that time is checked. If the output of the terminal AN0 switches from high to low in synchronization with the on / off of the switch connected to the terminal SW1 #, the switch connected to the terminal SW1 # operates corresponding to the 5-wire touch panel. As a result, the connected touch panel is determined as a 5-wire touch panel, and the process proceeds to step 21.

When the above voltage level change does not occur at the input terminal AN0, the connected touch panel is neither a 4-wire type nor a 5-wire type (or the switch unit connected to the terminal SW1 # may be broken). A determination is made and an error signal is sent (step 7).
Note that when a 4-wire touch panel is connected, since AN0 is not driven, voltage change does not occur and can be distinguished.

  If the connected touch panel is specified as a 4-wire type, the switch of the control circuit unit 10 is selected in step 11. That is, the switch selection unit 33 keeps the 5WireE1 # signal high and the connector switch selection unit 34 keeps the 5WireE2 # signal high, so that the predetermined switch can be operated.

Next, in step 13, the parameter selection unit 37 reads various parameters suitable for the 4-wire system from the parameter memory 41 of the memory 40 and stores them in the memory 43. Specifically, the address of the parameter stored in advance in the nonvolatile memory 40 is written in the memory 43, and the parameter can be accessed via the address written in the memory 43. Examples of this parameter include a voltage threshold value for determination of pressing, a weight until the start of A / D conversion, a weight for switching on / off of the transistors constituting the switch unit, and the like.
In step 15, the module selection unit 38 reads the control program module corresponding to the 4-wire system from the module memory 42 of the memory 40 and stores it in the memory 43. Specifically, the address of the control program module stored in advance in the nonvolatile memory 40 is written in the memory 43, and the control program is read out via the address written in the memory 43 to control the control circuit unit. Used for.

  If it is determined that the connected touch panel is a 5-wire type, the switch of the control circuit unit 10 is selected in step 21. In other words, the switch selection unit 33 keeps the 5WireE1 # signal low, the connector switch selection unit 34 keeps the 5WireE2 # signal low, and puts the predetermined switch into an operable state.

Next, in step 23, the parameter selection unit 37 reads out various parameters suitable for the 5-wire system from the parameter memory 41 of the memory 40 and stores them in the memory 43. Specifically, the address of the parameter stored in advance in the nonvolatile memory 40 is written in the memory 34, and the parameter can be accessed via the address written in the memory 43. As this parameter, the same one as in the case of the 4-wire system can be cited.
In step 25, the module selection unit 38 reads the control program module corresponding to the 5-wire system from the module memory 42 of the memory 40 and stores it in the memory 43. Specifically, the address of the control program module stored in advance in the nonvolatile memory 40 is written to the memory 43, and the control program is read out via the address written to the memory 43. Used for control.

  As described above, according to the control unit 1 of this embodiment, when touch panels having different driving methods shown in FIGS. 2 and 3 are connected, the driving method of the touch panel can be automatically specified. Then, a predetermined switch is selected from the control circuit unit so as to correspond to the specified driving method, and is operable. Thereby, drive control of two touch panels becomes possible with one control unit. In this embodiment, the components of the control circuit unit are shared by the 4-wire drive mode and the 5-wire drive mode. Therefore, the number of elements of the control unit is reduced, and this can be provided at a low cost.

Next, the driving method of the touch panel connected to the connector 20 is specified, the elements of the control circuit unit 10 are selected corresponding to the driving method, and further parameters and parameters necessary for operating the driving circuit unit 10 are selected. The control unit for which the control program module is selected automatically diagnoses whether or not it operates as planned.
This diagnosis can be performed not only at the initial stage when the touch panel is connected to the connector but also periodically as part of maintenance.

When the 4-wire touch panel shown in FIG. 2 is connected to the connector, the self-diagnosis is performed according to the flowchart of FIG.
When a check signal is input to the main controller 51 of the microcontroller 50 in step 31, the main controller 51 sends a command to the panel main controller 31 of the panel controller 30. The panel main controller 31 checks whether the module selected as the control program operates correctly (step 33). This check is performed, for example, by checking the checksums of all selected modules. When there is a defect in the selected module, that is, when there is a soft error, error transmission is performed (step 39). This error transmission is sent from the microcontroller 50 to, for example, the host computer via the input / output interface.

  When the selected module is normal, the process proceeds to step 41 to perform a hard check. The hard check here checks whether or not the functional parts of the control panel (specifically, the transistors constituting the switch unit) are normal (step 41). When the hard check is normal, the touch panel is driven (step 43). If the result of the hard check is NG, error transmission is performed (step 39).

The hard check in step 41 is performed by the diagnosis unit 36 controlling the switch controller 32, the switch selection unit 33, and the connector switch selection unit 34 based on a program stored in advance. Specifically, each switch is operated sequentially as shown in Table 6, and the voltage change at the input terminal of the A / D converter is analyzed. That is,
The switch unit connected to the terminal SW1 # is checked as follows. When the switch unit of the terminal SW2 is turned on, the switch unit of the terminal SW0 # is turned off, and the switch unit of the terminal SW1 # is turned on, the voltage level of the terminal AN0 is high and the switch unit of the terminal SW1 # is turned off If the voltage level of the terminal AN0 is low, it can be seen that the switch unit connected to the terminal SW1 # is normal.

The switch unit connected to the terminal SW2 is checked as follows. When the switch of the terminal SW1 # is turned on, the switch unit of the terminal SW0 # is turned off, and the switch of the terminal SW2 is on, the voltage level of the terminal AN1 is low, and when the switch SW2 is off, the voltage level of the terminal AN1 is If it becomes high, it turns out that the switch unit connected to terminal SW2 is normal.
The switch unit connected to the terminal SW3 # is checked as follows. If the switch of the terminal SW4 is turned on, the voltage level of the terminal AN2 is high when the switch of the terminal SW3 # is on, and the voltage level of the terminal AN2 is low when the switch unit of the SW3 # is off, the terminal SW3 It can be seen that the switch unit connected to # is normal.
The switch unit connected to the terminal SW4 is checked as follows. When the switch unit of the terminal SW3 # is turned on and the switch unit of the terminal SW4 is on, the voltage level of the terminal AN3 is low, and when the switch unit of the terminal SW4 is off, the voltage level of the terminal AN3 can be high. It can be seen that the switch unit connected to the terminal SW4 is normal.

  The switch unit connected to SW0 # for detection of pressing is checked as follows. The switch unit of the terminal SW1 # is turned off during the check. Then, it confirms that the voltage level of the terminal AN1 is high when the switch unit of SW2 is turned off and the switch unit of SW0 # is turned on. Then, with the switch unit of the terminal SW0 # turned off, the switch unit of the terminal SW2 is once turned on to discharge the charge on the touch panel. Thereafter, the switch unit of the terminal W2 is turned off. At this time, if the voltage level of the terminal AN1 becomes low, it is determined that the switch unit connected to the terminal SW0 # is normal.

In this way, when the 4-wire touch panel is connected, all switches (transistors) necessary for driving the touch panel can be diagnosed without operating the touch panel. Even when the touch panel itself has a problem, the voltage level of the input terminal of the A / D converter becomes indefinite. Therefore, when the above diagnosis is executed, it is determined as a problem of one of the switches. . However, by executing such a diagnosis, it becomes clear that there is a defect in the hardware elements of either the touch panel or the control unit. Therefore, by identifying that there is a hardware problem, it becomes possible to easily and quickly perform maintenance work such as investigation of the cause when a problem occurs in the system.
The order of switches to be checked is not particularly limited.

The self-diagnosis of the 5-wire touch panel is performed as follows.
The self-diagnosis of the 5-wire touch panel is performed according to the flowchart of FIG. 11 as with the 4-wire touch panel.
However, the operation of the switch is performed according to Table 7. Further, in executing the switch operation of Table 7, in this embodiment, as shown in FIG. 3, a Diagnostic line (diagnostic line) is added. This diagnostic line is connected to an upper resistance film (power supply side resistance film) constituting the touch panel. This diag line enables the electric charge of the touch panel to be discharged at an arbitrary timing by turning on the switch unit used for pressing determination.

When the 5-wire touch panel of FIG. 3 is connected, the hard check in step 41 sequentially operates each switch (transistor) as shown in Table 7 and analyzes the terminal output.
The transistor Q1 constituting the switch unit of the terminal SW0 # is checked as follows.
When waiting for a pressing interrupt, the upper resistive film is in a charged state because the switch unit of the terminal SW0 # is on. During operation, the charge is released through the lower resistance film by being pressed. However, since there is no user operation at the time of self-diagnosis, there is no means for discharging charges other than spontaneous discharge. Therefore, even if the input terminal AN14 of the A / D converter is measured, the voltage level change (high / low state change) does not occur immediately by turning on / off the switch unit of SW0 #. Therefore, as shown in FIG. 12, by using an arbitrary input / output port of the microcontroller (herein referred to as PE4), by changing this to a low output, the charge charged in the upper resistive film is discharged, It is possible to immediately determine that the switch unit of the terminal SW0 # has been turned off.

Specifically, the diagnostic line is set to a high impedance state, and the transistor Q1 constituting the switch of the terminal SW0 # is turned on. At this time, since the upper resistance film is pulled up via the resistor R, the voltage level of the input terminal AN14 becomes high. Thereafter, the switch unit of the terminal SW0 #, that is, the transistor Q1 is turned off, and the diagnostic line is set to low output to discharge the charge on the touch panel. After a certain time, return the diagnosis line to high impedance. Thereafter, the voltage level of the input terminal AN14 is confirmed. If it is low, it can be confirmed that the transistor Q1 is operating normally.
When the switch unit connected to the terminal of another control line is checked, the switch unit (transistor Q1) of the terminal SW0 # is always turned off.

The transistors Q2 and Q3 constituting the switch unit of the terminal SW1 # are checked as follows.
When the terminals SW2, SW3 #, and SW4 are both set high, the electrodes P2, P3, and P4 are both low as shown in FIG. Here, when the terminal SW1 # is made low, the electrode P1 becomes high and the voltage level of the input terminal AN0 connected to the electrode P1 becomes high. Thereafter, when both the terminals SW2, SW3 #, and SW4 are set to low, the electrode P3 is turned off, and both the electrodes P2 and P4 are set to high. At this time, when the terminal SW1 # is made high, the electrode P1 becomes low, and the voltage level of the input terminal AN0 connected to the electrode P1 becomes low.
If Q2 or Q3 does not operate normally, the assumed voltage level is different due to the influence of the electrode to which the input terminal AN0 is not directly connected. Therefore, when the above operation is performed normally, the transistor Q2, It can be determined that both Q3 are normal.

Similarly, the switch unit (transistors Q4 and Q5) connected to the control line terminal SW3 # is checked as follows.
When the terminals SW1 #, SW2, and SW4 are both set high, the electrodes P1, P3, and the electrode P4 are both low. Here, when the terminal SW3 # is set to low, the electrode P2 becomes high and the voltage level of the input terminal AN2 connected to the electrode P2 also becomes high. Thereafter, when the terminals SW1 #, SW2, and SW4 are both low, the electrode P3 is turned off and the electrodes P1 and P4 are both high. At this time, when the terminal SW3 # is made high, the electrode P2 becomes low and the voltage level of the input terminal AN2 connected to the electrode P2 also becomes low. If Q4 or Q5 does not operate normally, the assumed voltage level is different due to the influence of the electrode to which the input terminal AN2 is not directly connected. Therefore, when the above operation is executed normally, It can be determined that both the transistors Q4 and Q5 are normal.

Similarly, the switch unit (transistors Q7 and Q8) connected to the terminal SW4 is checked as follows.
When the terminals SW1 #, SW2, and SW3 # are both high, the electrodes P1, P3, and the electrode P2 are both low. When the terminal SW4 is set to low here, the electrode P4 becomes high and the voltage level of the input terminal AN3 connected to the electrode P4 also becomes high. Thereafter, when the terminals SW1 #, SW2, and SW3 # are all low, the electrode P3 is turned off and the electrodes P1 and P2 are both high. At this time, when the terminal SW4 is made high, the electrode P4 becomes low and the voltage level of the input terminal AN3 connected to the electrode P4 also becomes low. If the transistor Q7 or Q8 does not operate normally, the assumed voltage level is different due to the influence of the electrode to which the input terminal AN3 is not directly connected. Therefore, when the above operation is executed normally, It can be determined that both the transistors Q7 and Q8 are normal.

The switch unit (transistor Q6) connected to the terminal SW2 is checked as follows.
When the terminals SW1 #, SW3 and SW4 are all low, the electrodes P1, P2 and the electrode P4 are both high. Here, when the terminal SW2 is set to low, the electrode P3 is turned off, and the voltage level of the input terminal AN1 connected to the electrode P3 becomes high. Thereafter, when the terminal SW2 is set to high, the electrode P3 becomes low, and the voltage level of the input terminal AN1 connected to the electrode P3 also becomes low. If the transistor Q6 does not operate normally, the assumed voltage level is different due to the influence of the electrode to which the input terminal AN1 is not directly connected. Therefore, when the above operation is normally performed, the transistor It can be determined that both Q6 are normal.

In this way, when a 5-wire touch panel is connected, all elements (transistors) necessary for driving the touch panel can be diagnosed without operating the touch panel. Even if the touch panel itself is defective, the voltage level applied to the input terminal of the A / D converter does not change, resulting in an unexpected result. This is determined as a failure of the transistor. However, by executing such a diagnosis, it becomes clear that there is a defect in the hardware elements of either the touch panel or the control unit. Therefore, maintenance work such as investigation of the cause when a problem occurs in the system is facilitated.
The order of the switch units (transistors) to be checked is not particularly limited.

  The present invention is not limited to the description of the embodiments and examples of the invention described above. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.

FIG. 1 is a block diagram showing the overall structure of the control unit of the present invention. FIG. 2 shows the driving principle of a 4-wire touch panel. FIG. 3 shows the driving principle of a 5-wire touch panel. FIG. 4 also illustrates the basic configuration of the 5-wire touch panel. FIG. 5 also illustrates X-direction driving of a 5-wire touch panel. FIG. 6 also illustrates Y-direction driving of the 5-wire touch panel. FIG. 7 similarly illustrates the pressing detection principle of the 5-wire touch panel. FIG. 8 is a detailed diagram of the control circuit unit (corresponding to the 5-wire type) of the embodiment. FIG. 9 is a detailed diagram of the control circuit unit (corresponding to a 4-wire type) of the embodiment. FIG. 10 is a flowchart for explaining the operation of automatically recognizing the touch panel drive method. FIG. 11 is a flowchart for explaining the self-diagnosis operation of the touch panel. FIG. 12 illustrates the self-diagnosis principle of the switch unit of the press detection terminal SW0 # in the 5-wire touch panel. FIG. 13 illustrates the self-diagnosis principle of the switch unit of the terminal SW1 # in the 5-wire touch panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control unit 10 Control circuit part 20 Connector 24 4-wire touch panel 25 5-wire touch panel 30 Panel controller 32 Switch controller 33 Switch selection part 34 Connector switch selection part 35 Drive system specific | specification part 37 Parameter selection part 38 Module selection part 40 Memory

Claims (4)

Touch panel control capable of driving the connected touch panel regardless of which one of the first touch panel driven by the first driving method or the second touch panel driven by the second driving method is connected. A unit,
The first control circuit corresponding to the first driving method and the second control circuit corresponding to the second driving method constitute a switch unit of the first control circuit and the second control circuit. A control circuit unit that shares and includes a switch unit composed of transistors ;
A connector capable of connecting the first touch panel or the second touch panel to the control circuit unit ;
Operating the transistors in a predetermined combination and detecting a voltage level of a specific panel voltage detection terminal signal synchronized with the transistor operation connected to an input terminal of an A / D converter connected to the control circuit unit; Accordingly, a driving method specifying unit driving method of a touch panel connected to the connector is identified whether the second driving mode or a first driving mode,
A first selection unit for outputting a control signal based on a driving mode that has been specified by the driving scheme specifying unit selects one of said first control circuit the second control circuit,
Operating the transistors in a predetermined combination and detecting a voltage level of a specific panel voltage detection terminal signal synchronized with the transistor operation connected to an input terminal of an A / D converter connected to the control circuit unit; By the diagnostic unit for diagnosing whether the operation of the transistor constituting the switch unit that is not brought into a stopped state by the first selection unit ,
A touch panel control unit. The first driving method is a four-wire resistive film method, and the second driving method is a five-wire resistive film method,
In the switch unit which is included in the control circuit unit, three of the four said switch unit associated with the voltage detection in the X direction and Y direction of the touch panel comprises a pair of transistors, the other one 1 It consists of One of the transistor,
The first selecting unit, when driving method specified by the driving method specific portion of the first driving system, by one of each pair of transistors constituting the three switch units in a stopped state The touch panel control unit according to claim 1, wherein a control signal for selecting the first control circuit is output . A first parameter storage unit for storing a first parameter for executing the first driving method;
A second parameter storage unit for storing a second parameter for executing the second driving method;
A first program module storage unit for storing a first control program module for executing the first drive method;
A second program module storage unit for storing a second control program module for executing the second driving method;
A second selection unit that selects a parameter based on the drive method specified by the drive method specification unit; and a third selection unit that selects a control program module based on the drive method specified by the drive method specification unit;
The touch panel control unit according to claim 1, further comprising: When the drive method specifying unit cannot identify whether the touch panel drive method is the first drive method or the second drive method, or when the diagnosis unit diagnoses that the operation of the transistor is not normal a touch panel control unit according to any one of claims 1 to 3, further comprising a means for sending an error signal.

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