JPH0635412A - Display device - Google Patents

Abstract

PURPOSE:To facilitate the connection between the main part and operation part of the display device of electronic equipment such as an audio device. CONSTITUTION:After serial data outputted from a control circuit 62 are converted into parallel data, a display panel 10 is driven according to the parallel data and a specific output port is driven; and the operation of the control circuit 62 is switched by outputting key scan data according to the input result of a key input means 36 and after the serial data outputted from this control circuit 62 are converted into parallel data, the display panel 10 is driven according to the parallel data.

Description

Detailed Description of the Invention

[0001]

[Table of Contents] The present invention will be described in the following order. Industrial Application Conventional Technology (FIG. 3) Problem to be Solved by the Invention (FIGS. 3 to 5) Means for Solving the Problem (FIG. 2) Action (FIG. 2) Example (1) Example Configuration (FIGS. 1 and 2) (2) Effect of the embodiment (3) Other embodiment Effect of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and can be applied to, for example, a car audio device.

[0003]

2. Description of the Related Art Conventionally, in a car audio device or the like, a liquid crystal display panel has been used to display operation modes and the like.

That is, as shown in FIG. 3, in this kind of audio equipment 1, a system control circuit 4 is mounted on a main board 2 on which an audio signal processing circuit and the like are mounted.
While controlling the entire operation, the power supply circuit 6 mounted on the main board 2 supplies drive power.

On the other hand, in the sub-board 8 mounted on the back surface of the front panel, for example, a predetermined connector 9
It is connected to the main substrate 2 via A and 9B, and a liquid crystal display panel (LCD) 10 is driven by an LCD driver 12 to display operation modes and the like. Therefore, in the LCD driver 12, the chip enable signal CE and the clock signal CL, which are latch signals, are output via the connectors 9A and 9B.
K, the display data DATA of the liquid crystal display panel is input from the system control circuit 4, whereby the operation mode and the like can be displayed as needed.

Further, on the sub-board 8, light emitting diodes 14 to 18 forming an indicator are mounted, and the light emitting diodes 14 to 18 are turned on so that various operations can be monitored.

Therefore, on the sub-board 8, the transistors 20 to 24 forming the drive circuits for the light emitting diodes 14 to 18, the resistors 26 to 32, and the diode 34 are mounted, and the main circuit is mounted via the connectors 9A and 9B. The power supply B, the display switching signal SEL, the indicator lighting signal IN, and the ground GND are input from the substrate 2.

Further, the sub-board 8 has a key input section 36 having a matrix structure, and each signal line forming the key matrix is connected to the system control circuit 4 via the connectors 9A and 9B. As a result, in the audio device 1 of this type, the system control circuit 4 scans the key matrix to detect the pressing operation of the operator arranged on the front panel, and the operation can be switched based on the detection result. Has been done.

[0009]

By the way, in the audio device 1 of this type, the main substrate 2 and the sub substrate 8 are provided.
It is necessary to connect a large number of cables to connect between them, and there is a problem that the entire configuration becomes complicated accordingly.

Particularly in this kind of audio device,
It is possible to improve usability by providing various indicators. If this type of indicator is added, the number of cables also increases, and the configuration becomes more complicated.

FIG. 4 shows one method for solving this problem.
As shown in FIG. 4, a method of mounting the key microcomputer 38 for scanning the key input unit 36 and detecting the pressing operation of the operator on the sub-board 8 is conceivable. In this method, however, the configuration of the sub-board 8 becomes complicated. Become.

On the other hand, as shown in FIG. 5, a resistor circuit network 40 formed by connecting resistors in series is mounted on the sub-board 8, and a DC voltage which changes in response to a pressing operation of an operator 42 is analog. A method of detecting with the digital conversion circuit (A / D) 44 is also conceivable. However, in this method, there is a risk of malfunction when a plurality of operating elements 42 are pressed simultaneously, or when noise is mixed in, which is practical. Not at all.

The present invention has been made in consideration of the above points, and an object thereof is to propose a display device capable of simplifying the connection between the main portion and the operating portion.

[0014]

In order to solve such a problem, in the first invention, the operating portion 8 and the main portion 2 are formed as separate bodies, and the operating portion 8 and the main portion 2 are connected to each other to form an overall structure. In the electronic device 50 that controls the operation, the main unit 2 includes a control circuit 62 that controls the entire operation, and the operation unit 8 includes
The display driving circuit 66 has a display driving circuit 66, and the display driving circuit 66 inputs the serial data DATAIN output from the control circuit 62 and the serial data DATAIN input via the input port to the parallel data DATAI.
And a serial interface circuit for converting to N,
Display panel 10 based on parallel data DATAIN
And a predetermined output port.

Further, in the second invention, the operating portion 8 is
Display drive circuit 6 having indicators 14, 16 and 18
6 drives the output port to drive the indicators 14, 16,
18 is driven.

Further, in the third aspect of the invention, in the electronic device 50 in which the operating section 8 and the main section 2 are formed separately and the operating section 8 and the main section 2 are connected to control the overall operation,
The main unit 2 has a control circuit 62 for controlling the entire operation, and the control circuit 62 has an input port for inputting serial data, and the whole based on the key scan data DATAOUT input via the input port. The operation unit 8 has a predetermined key input unit 36 and a display drive circuit 66, and the display drive circuit 66 has an input port for inputting the serial data DATAIN output from the control circuit 62. A serial interface circuit for converting serial data DATAIN input via the input port into parallel data DATAIN, and key input means 3.
Key scan data DATA based on the input result of 6
It has a key scan data output port for generating OUT, converting it into serial data and outputting the serial data, and drives the display panel 10 based on the parallel data DATAIN.

Further, in the fourth invention, the operating section 8 is
Display drive circuit 6 having indicators 14, 16 and 18
2 drives the display panel 10 based on the parallel data DATAIN, and also displays the indicators 14, 16, 1
Drive eight.

[0018]

The serial data D output from the control circuit 62
After converting ATAIN into parallel data DATAIN, the display panel 10 is driven based on the parallel data DATAIN, and if a predetermined output port is driven, the operation unit 8 and the main unit 2 are separately formed. Even in this case, the connection between the operation unit 8 and the main unit 2 can be simplified.

This allows the output port to be driven to drive the various indicators 14,16,18.

Based on the input result of the key input means 36,
After outputting the key scan data DATAOUT to switch the operation of the control circuit 62 and converting the serial data DATAIN output from the control circuit 62 into parallel data DATAIN, the parallel data DAIN is output.
Driving the display panel 10 based on TAIN can simplify the connection between the operation unit 8 and the main unit 2 even when the operation unit 8 having the key input means 36 and the main unit 2 are formed separately.

As a result, various indicators 1 are added to the display panel 10 based on the parallel data DATAIN.
It is possible to drive 4, 16, and 18 to simplify the entire configuration.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

(1) Configuration of Embodiment In FIG. 1, reference numeral 50 denotes a car audio device as a whole, and a signal processing circuit and the like are housed in a main body 52 of the audio device.

In the audio device 50, as shown by the arrow a, the operating portion 56 in which the operator 54 and the liquid crystal display panel 10 are arranged is provided with respect to the audio device main body 52.
The car audio device 50 can be prevented from being stolen by removing the operation portion 56 and carrying it when the vehicle is parked on the road.

As shown in FIG. 2, the audio device main body 52 accommodates the main board 2 on which the signal processing circuit is mounted, and the operation section 56 is mounted on the audio device main body 52 with a predetermined connector 60A, It is connected to the audio apparatus main body 52 via 60B, and the operation section 56 is adapted to mount the sub-board 8.

On the main board 8, the system control circuit 62 controls the operation of the entire audio device and outputs the display data DATAIN for driving the liquid crystal display panel 10 to the sub-board 8 as necessary.

At the time of this data transmission, the system control circuit 62 outputs the display data DATAIN via the built-in serial / parallel interface circuit, converts the display data composed of parallel data into serial data, and then outputs the clock signal. CLK, chip enable signal C
It is designed to output based on E. As a result, in the audio device 50, the connection between the main board 2 and the sub-board 8 is simplified, and the connectors 60A and 60B are connected.
It is designed to reduce the number of contacts.

Further, the system control circuit 62 assigns the undefined bit of the display data DATAIN to the control data for driving the light emitting diode, and thereby transmits the control data for driving the light emitting diode. Accordingly, in the audio device 50, the signal line for driving the liquid crystal display panel is effectively used to send the data for indicator lighting, and the connection between the main substrate 2 and the sub substrate 8 is simplified accordingly. The number of contacts of the connectors 60A and 60B is reduced.

Further, in the system control circuit 62,
The key scan data DATAOUT output from the sub-board 8 is input through the built-in input port, and the operation of the operator 54 is detected based on the key scan data DATAOUT.

At this time, in the system control circuit 62, the chip enable signal CE and the clock signal CLK
After inputting the key scan data DATAOUT in the form of serial data, the data is converted into parallel data through the serial / parallel interface circuit and processed.
And the connection between the sub-board 8 is simplified, and the connector 60A,
The number of contacts of 60B is reduced.

In practice, as in this embodiment, the operating section 56
The connector 60A, 60B so that the connector can be removed.
When connecting the audio device main body 52 and the operation unit 56 via the connector, the reliability decreases as the number of contacts of the connectors 60A and 60B increases. Furthermore, when the number of contacts of the connectors 60A and 60B is large, the mounting operation requires more force and the mounting mechanism becomes complicated.

Therefore, when the operation portion 56 is formed so as to be detachable as in this embodiment, and the audio device main body 52 and the operation portion 56 are connected via the connectors 60A and 60B, the main board 2 is thus connected. If the number of contacts between the sub-board 8 and the
Not only can the configuration of B be simplified, but the overall configuration can also be simplified and reliability can be improved.

Further, in the system control circuit 62,
By transmitting the control data for driving the light emitting diode by using a part of the display data DATAIN, the number of output ports required for the operation unit 56 can be reduced accordingly. Therefore, the remaining output ports of the system control circuit 62 can be assigned to another function and used, and the usability of the entire audio device 50 can be improved accordingly.

Further, as described above with reference to FIG. 3, the required wiring pattern amount can be reduced as compared with the case where the key input section 36 is directly connected, and the overall shape can be reduced accordingly, and the wiring can be further reduced. Since the amount of putter can be reduced, the influence of unwanted radiation can be reduced.

Corresponding to the system control circuit 62, in the sub-board 8, the chip enable signal CE, the clock signal CLK, and the display data DATAIN are input to the LCD driver 66.

Here, the LCD driver 66 is formed of an integrated circuit, and after latching the display data DATAIN to the built-in input port on the basis of the chip enable signal CE and the clock signal CLK, it continues the serial parallel interface. Convert to parallel data in the circuit. As a result, the LCD driver 66 drives the liquid crystal display panel 10 based on the display data DATAIN and turns on the indicators 14 to 18.

Of the light emitting diodes 14 to 18, the light emitting diodes 16 and 18 form illumination light for illumination, and the operating portion 56 is
The lighting of the light emitting diodes 16 and 18 can be switched to switch the color of the illumination.

Thus, the liquid crystal display panel 10 and the indicators 14 to 18 can be turned on with a small number of wires by transmitting the control data for driving the light emitting diode by utilizing a part of the display data DATAIN.

Further, the LCD driver 66 scans the key input section 36 on the basis of the clock signal CLK, and when any pressing operation of the operator is detected, the detection result is output as the key scan data DATAOUT. To do.

In the output process of the key scan data DATAOUT, the LCD driver 66 generates parallel data of a predetermined bit based on the detection result, then converts this parallel data into serial data, and this serial data is a chip enable signal. It is transmitted based on the CE and clock signals CLK.

As a result, in the audio device 50, even if the number of wires between the main board 2 and the sub-board 8 is reduced, the operation of the operator 54 can be reliably detected, and a plurality of operators can be simultaneously operated as necessary. Even when the pressing operation is performed, the pressing operation can be detected.

(2) Effects of the Embodiments According to the above configuration, the LCD driver 66 drives the light emitting diodes 14 to 18 together based on the display data to connect the main board 2 and the sub-board 8. It can be simplified. Further, at this time, the LCD driver 66 scans the key input section 36 and outputs the detection result to the main board 2, so that the connection between the main board 2 and the sub-board 8 can be further simplified.

(3) Other Embodiments In the above embodiment, the case where the key matrix is arranged as the key input means has been described, but the present invention is not limited to this, and various key input means are widely applied. can do.

Further, in the above-mentioned embodiments, the case of driving the liquid crystal display panel has been described, but the present invention is not limited to this, and can be widely applied to the case of driving various display panels such as a plasma display. .

Further, in the above-mentioned embodiment, the case where the light emitting diode is driven as the control target of the output port has been described, but the present invention is not limited to this, and a buzzer or the like may be driven.

Further, in the above-mentioned embodiment, the case where the data is transmitted between the main board and the sub-board on the basis of the chip enable signal and the clock signal which are the latch signals has been described, but the present invention is not limited to this. This chip enable signal may be omitted.

Further, in the above embodiment, the case where the present invention is applied to the car audio system has been described.
The present invention is not limited to this, and can be widely applied to display devices of various electronic devices in which the operation unit is formed separately.

[0048]

As described above, according to the present invention, after converting the serial data output from the control circuit into parallel data, the display panel is driven based on the parallel data and a predetermined output port is driven. By
Even when the operation unit and the main unit are formed separately, it is possible to obtain a display device in which the connection between the operation unit and the main unit can be simplified. Further, based on the input result of the key input means, the key scan data is output to switch the operation of the control circuit, and the serial data output from the control circuit is converted into parallel data, and then based on the parallel data. By driving the display panel, it is possible to obtain a display device capable of simplifying the connection between the operation unit and the main unit even when the operation unit having the key input means and the main unit are separately formed.

[Brief description of drawings]

FIG. 1 is a perspective view showing an audio device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the relationship between the main board and the sub-board.

FIG. 3 is a block diagram showing a conventional audio device.

FIG. 4 is a block diagram showing a case where a key microcomputer is mounted on a sub-board.

FIG. 5 is a block diagram showing a case where an operation of an operator is detected by an analog digital conversion circuit.

[Explanation of symbols]

1, 50 ... Audio device, 2 ... Main board, 4,
62 ... System control circuit, 8 ... Sub-board, 9A, 9
B, 60A, 60B ... Connector, 10 ... Liquid crystal display panel, 12, 66 ... LCD driver, 20-23 ...
Light emitting diode, 36 ... Key input section.

Claims (4)

[Claims] 1. An electronic device in which an operation section and a main section are formed separately, and the operation section and the main section are connected to control the overall operation. The main section controls the overall operation. A control circuit is provided, the operation unit has a display drive circuit, and the display drive circuit has an input port for inputting serial data output from the control circuit, and an input port for inputting via the input port. A display device comprising: a serial interface circuit for converting serial data into parallel data; and driving a display panel and a predetermined output port based on the parallel data. 2. The display device according to claim 1, wherein the operation section has an indicator, and the display drive circuit drives the output port to drive the indicator. 3. An electronic device in which an operation section and a main section are formed separately, and the operation section and the main section are connected to control the overall operation, wherein the main section controls the overall operation. A control circuit, the control circuit has an input port for inputting serial data, and controls the overall operation based on key scan data input via the input port; Key input means and a display drive circuit, wherein the display drive circuit inputs the serial data output from the control circuit, and the serial data input via the input port in parallel data. A serial interface circuit for converting into a serial interface circuit and a key interface for generating the key scan data based on the input result of the key input means, converting the serial data into serial data, and outputting the serial data. A display device having a CAN data output port and driving a display panel based on the parallel data. 4. The operation unit has an indicator, and the display drive circuit drives the display panel based on the parallel data and drives the indicator. Display device.