KR20010020945A - Method of driving a plurality of chained displays, driver, chainable displays, and chained display system - Google Patents

Abstract

PURPOSE: To attain easiness of extension by enabling many display devices to be chainingly connected in a state of which physical restrictions from respective devices are eliminated without changing the hardware of a system side. CONSTITUTION: This system is provided with a display driving device 1 outputting a video signal which is to be displayed with respect display areas and a chained display signal which is to be added to the video signal and also which uses at least the timing of one line, a first display device 2(1) capable of displaying a video with respect the display area of itself based on the video signal by inputting the video signal and the chained display signal and also by analyzing the chained display signal while being connected to the device 1 and a second display device 2(2) capable of displaying the video with respect to the display area of itself based on the video signal by inputting the video signal and the chained display signal and also by analyzing the chained display signal while being connected to the first display device 2(1).

Description

Method of driving a plurality of chained displays, driver, chainable displays, and chained display system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using an LCD panel and the like, and more particularly, to a method of driving a plurality of chain display devices, a drive device, a display device capable of chain connection, and a chain display system.

In recent years, a technique has been proposed in which a plurality of display panels are connected to a personal computer (PC), a plurality of small display panels are integrated, and the whole is used as a display having one large screen. At this time, in the specification of the conventional interface, one display panel is displayed for each video chip, for example. Four video chips are required to display different images on four display panels. Therefore, in order to display a plurality of display panels on the basis of a conventional interface, the expansion of the display panel is limited because only a maximum of 4 to 8 panels can be connected due to the limitation of the space, slots and the number of connections in the PC case.

Further, in the case of displaying different images on four display panels in four video chips by the conventional method, for some time, the CPU of the PC updates only the memory of one video chip. Therefore, during this time, the memory of the remaining three video chips simply has the function of maintaining the screen.

Here, Japanese Patent Laid-Open No. Hei 9-319550 is a conventional technique for connecting a plurality of display apparatuses (monitor apparatuses) to one PC apparatus. In this prior art, the display apparatus is connected in parallel to a PC apparatus capable of simultaneously executing a plurality of programs using a plurality of display apparatuses, and each display apparatus is operated by a storage instruction key provided therein or a storage instruction transmitted from the PC apparatus. It is possible to select whether to receive an image signal based on the signal, and to display an image according to the selection result. According to this technique, an image can be displayed by each display device without being limited by the hardware configuration in the number of programs that can be executed simultaneously.

Similarly, the prior art for connecting a plurality of display devices to one PC is disclosed in Japanese Patent Laid-Open No. 9-274475. This publication discloses a technique of inserting ID information immediately before the video data of the first line for each frame and obtaining the video data only when it matches the ID preset in each display device. According to this technique, a plurality of display devices can be driven by one output from a PC device, and wiring can be simplified.

On the other hand, in recent years, digital interfaces are mainly introduced into notebook PCs, and at present, PCs and displays are simply used in one-to-one connection. It is proposed to apply the Gigabit Video Interface (GVIF) by Sony Corporation for the technology of connecting a plurality of displays in a daisy chain state. Afterwards, it is expected that the form of connecting the digital interfaces in a chained state will gradually increase.

However, in the technique disclosed in Japanese Patent Laid-Open No. 9-319550, wiring is complicated because each display device is connected in parallel, and an interface must be provided between the PC device and the display device, respectively. In addition, since the memory signal detection circuit must be provided for each display device, the hardware configuration will be complicated.

Further, in the technique disclosed in Japanese Patent Laid-Open No. 9-274475, the operation of the display device is complicated because an ID setting circuit must be provided for each display device, and an ID must be set every time a plurality of displays are changed. . Also, this publication merely discloses matching of ID information, and different control cannot be executed for each display device by the PC device.

In addition, in order to implement the GVIF technology, it is necessary to build new hardware and install a video port by a new display control circuit. In addition, when sending command information on which display information is written to which display device or how to control the display device, the information is separated and transmitted by the technique disclosed herein. There is a need. In such a case, it is necessary to change the software, the hardware, or increase the number of interface lines.

The present invention has been made to solve such technical problems, and its object is to facilitate expansion by allowing more display devices to be connected without removing physical restrictions from each device.

It is another object of the present invention to transmit command information to a connected display device without changing hardware on the system side, and in particular, to transmit command information by rewriting a register in a video chip, and distinguishing it from screen information. Can be sent automatically without.

It is still another object of the present invention to enable enlarged display by using a plurality of chain-connected display devices by simply changing the software, and to display screen information individually based on command information on a plurality of chain-connected display devices. It is to let.

1 is a block diagram showing a chain display system of this embodiment.

2 is an explanatory diagram showing a relationship between screen information and a control command of the first embodiment;

3 is an explanatory diagram showing the format of a command line in the first embodiment;

4 is an explanatory diagram showing an example of data insertion in a header block;

5 is an explanatory diagram showing an example of inserting an instruction in an instruction block;

6 is an explanatory diagram showing an enlarged display application using the MDA format of the present embodiment.

Fig. 7 is an explanatory diagram showing a relationship between screen information and a control command in the second embodiment.

Fig. 8 is an explanatory diagram showing instruction insertion timing of the second embodiment.

<Explanation of symbols for main parts of drawing>

1: Personal Computer

2 (1) to 2 (n): display panel

11: CPU

12: input / output circuit

13: RAM

14: ROM

15: display control circuit

21: digital receiver

22: digital transmitter

23: control circuit

24: frame memory

25: liquid crystal display control circuit

26 liquid crystal display circuit

31: display area

32: command line

41: header block

42: command block

51: video card

52: display panel

53: first display panel group

54 second display panel group

61: command area

62: n-line screen information

63: n + 1 line screen information

64: blanking

65: control command

In order to solve the above problems, the present invention provides a driving method for driving a plurality of serial display apparatuses, in which display timings not displayed in the display region are added to display timings visible in the display region of the display apparatus. At the same time as writing a control command for controlling the display device at the display timing, the control command is characterized in that it includes selection information for selecting a display device from a plurality of serial display devices and control information of the selected display device.

The display timing that is not displayed in the display area of this display device can be either up, down, left, or right of the display area, but a method of using end blanking for each line on the right side of the display area or a predetermined line after the end of the frame at the bottom of the display area According to the method of using, there is no need to change the display criterion in this image display area since the display criterion generally exists at the left end. In particular, the use of timing to form at least one line formed after the last line of this display area is advantageous in that blanking can be reduced at the end of each line.

In addition, if the control command used here is composed of a command line consisting of a header block portion and a command block portion, and this header block portion is specified by a block containing header information necessary for modifying the display device, It is preferable in that it can send out command information, such as how to record screen information to a display apparatus or how to control the display apparatus only by a change. In addition, this header information includes version information of the chained display control software or an auto increment ID that increases each time it passes through the connected display device.

In addition, the driving method transmits the same screen information to a plurality of display apparatuses in order to form a large screen by an enlarged display, and the selection information selects all of the plurality of display apparatuses to form a large screen by an enlarged display. Information, and the control information is characterized in that the screen information is separately divided and enlarged and displayed for the display device constituting the large screen. For example, even when the resolution is enlarged and displayed, a new update operation for one image is performed. It is preferable at the point that it is not necessary. In particular, when a liquid crystal display device (LCD) is used as a display device, it is excellent in that connection is easy for each screen when a large screen is formed by a plurality of display devices.

In addition, the present invention provides a driving method for driving a plurality of serial display apparatuses, the display timing of not being displayed in the display area is added to the display timing visible in the display area of the display device, thereby providing a display device with respect to the added display timing. At the same time as writing a control command to control, this control command includes ID information which is updated each time it passes through a plurality of serial display devices. Even when each display device loses its ID information at the initial stage of power supply ON / OFF or the like, it is preferable in that it can automatically have its ID by receiving this control command. In particular, this ID information is effective in that it can be added automatically every time it passes through a plurality of serial display apparatuses, so that the function can be achieved by simplifying the software.

In addition, if the display apparatus is configured to recognize its own ID based on the ID information and to execute the display operation based on the indication information of the ID to perform the display operation included in the control command, It is preferable at the point which can freely select each chained display apparatus and perform a display operation, without setting ID individually.

On the other hand, the present invention is a drive device for driving a plurality of chain display device, the image signal generating means for generating an image signal for display on the display area of the display device, and the image display of the display area based on the generated image signal A chain display signal generating means for generating a chain display signal using a display timing not used in the step; and a chain display signal generated by the chain display signal generating means to a video signal generated by the video signal generating means, And an output means for outputting this chained display signal to any chained display device.

In particular, the chain display signal generated by the chain display signal generating means is characterized by a chain display signal using a timing of at least one line not used for the image display of this display area based on the generated video signal. It is preferable in that the display criteria do not need to be changed in the display, and the chained display apparatus can be controlled by the addition of simple display timing.

Further, the chain display signal generated by the chain display signal generating means includes selection information for selecting a display device from a plurality of chain display devices, and control information for controlling the selected display device. It is possible to designate an arbitrary device from a chained display device only by changing the software, and to perform video display without changing the number of lines or increasing the number of lines of the interface.

In addition, the chain display signal generated by the chain display signal generating means includes selection information for selecting all of the plurality of chain display apparatuses, thereby concatenating the same image signal generated by the image signal generating means to the plurality of chain display apparatuses. The concatenated display signal may further include control information for separately dividing the video signal for a plurality of display devices, and for displaying the divided video signal in an enlarged manner in the display device. It is preferable at this point that a large screen can be comprised by integrating several some connected display apparatuses.

In addition, the drive device in the present invention can be realized in the form of a video card or the like, for example, an additional board connected to a connector inside a PC.

The present invention also provides an image signal output from the display driving apparatus in a display apparatus which is connected in a chained state to a display driving apparatus that outputs an image signal and a control command for controlling the chain display apparatus to display on the display apparatus to be cascaded. A digital receiver for inputting a control command formed at a display timing which is added to the video signal and not displayed, a control circuit for interpreting the control command input by the digital receiver, a frame memory for storing the video signal, a video signal, And a digital transmitter for outputting to a display device connected to the control command added to the video signal. Instead of having a screen information holding memory on the system side, which is a display driving device, having this frame memory on the display device side makes it possible to display images with a plurality of display devices by a single display control circuit.

Further, in this display device, the control circuit determines whether to display the video signal on its display device by the interpreted control command, and the digital transmitter determines whether to display the video signal made by this control circuit. Irrespective of the determination, the video signal and the control command are connected and then output to the display device, which is preferable in that it can serve as a simple buffer. Here, the control command outputted from the digital transmitter does not necessarily have to match the control command input by the digital receiver, and some of the contents may be different, for example, added ID information. Similarly, the video signal does not necessarily need to match, but if the video signal is output to another display device as it is, there is no need to perform video signal change processing.

In addition, in the present invention, the chain display system drives a display for outputting a video signal displayed on the display area and a chain display signal using timing of at least one line which is added to the video signal and not used for the video display. A first display device which is connected to the device and the display driving device, inputs a video signal and a chain display signal, analyzes the chain display signal, and displays an image on its display area based on the video signal. And a second display device connected to the first display device for inputting a video signal and a chain display signal, interpreting the chain display signal, and displaying an image on its own display area based on the video signal. Equipped It is characterized by. Here, in each of these display devices, the video display does not necessarily need to be all of the video signals, but only the partial display. In particular, when the enlarged display is performed using a plurality of four or more display devices, the divided image may be enlarged and displayed. In addition, the chain display signal input to the first display device and the chain display signal input to the second display device need not necessarily coincide with each other as described above, and there is no problem even if other information such as added ID information is included. .

First embodiment

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on the Example shown to an accompanying drawing.

1 is a block diagram illustrating an embodiment of a chain display system to which the present invention is applied. Reference numeral 1 in Fig. 1 is a personal computer PC, which serves as a driving device for driving the display device in this embodiment. Reference numeral 12 of the personal computer 1 is an input / output circuit composed of a keyboard or a mouse, 13 is a RAM composed of a hard disk or an IC or the like in which data such as a video signal is stored, and 14 is a control program stored therein. ROM. The video signal used for the display may be generated by the personal computer 1 of the present embodiment, or may handle the video signal generated externally. In addition, 11 is a CPU, and the execution process of the personal computer 1 is performed according to the instruction | command of the user from the control program or the input / output circuit 12 from ROM14. Reference numeral 15 denotes a display control circuit. The display control circuit 15 is controlled by the CPU 11 and at the same time controls the display device such as how to record a video signal (screen information) on the connected display panel or control the display panel such as brightness control. It is a circuit which performs control, generates a command line including control commands, and adds this command line to a video signal (screen information) and outputs it to a display panel described later.

In Fig. 1, reference numerals 2 (1) to 2 (n) denote display panels. In the present embodiment, a liquid crystal panel (LCD) is used and a plurality of display panels 2 (1) to 2 (n). )] Is connected in a daisy chain state. In the display panels 2 (1) to 2 (n), reference numeral 21 is a digital receiver for receiving a video signal (screen information) and a chain display signal (control command), and 22 denotes this screen information and The digital transmitter outputs control commands to the display panel. Here, the digital receiver 2a of the first display panel 2 (1) receives an output from the display control circuit 15 of the personal computer 1 and outputs the second display panel 2 (2). The digital receiver 21 receives the output from the digital transmitter 22 in the first display panel 2 (1). Similarly, the digital receiver 21 of the nth display panel 2 (n) receives an output from the digital transmitter 22 of the nth display panel 2 (n-1), not shown. These transceivers enable the chained state as a system.

Further, reference numeral 23 denotes a control circuit for controlling each display panel 2 (1) to 2 (n) based on a control command received by the digital receiver 21, and 24 denotes a digital receiver 21. Is a frame memory for storing screen information received by &lt; RTI ID = 0.0 &gt; 25, &lt; / RTI &gt; a liquid crystal display control circuit which sequentially extracts information for one screen stored in the frame memory 24 and controls the liquid crystal display circuit 26 described later. And 26 are liquid crystal display circuits which actually display an image on the screen of the LCD in a state controlled by the liquid crystal display control circuit 25.

FIG. 2 is an explanatory diagram showing the relationship between screen information and control commands generated in the display control circuit 15 of the personal computer 1 and transmitted to the display panels 2 (1) to 2 (n). In the present embodiment, the command line 32 as a control command is added after the last line of the display area 31 actually displayed on the display panels 2 (1) to 2 (n). As shown in Fig. 2, the embodiment employs XGA (eXtended Graphics Array), which is a display resolution of 1024 x 768, and the display area 31 has 1024 dots in the data line direction and 768 lines in the gate line direction. The command line 32 is formed at 769 lines next to 768 lines. In the command line 32, as described above, control commands indicating the designation of the display panels 2 (1) to 2 (n) to which the screen information should be recorded, or how to control the selected display panel are formed. It is. The display panels 2 (1) to 2 (n), which have received the screen information of the display area 31 and the control commands formed on the command line 32, interpret these control commands and display the presence or absence of a display on their own panels. Or determining the display method.

Fig. 3 shows the format of the command line in this embodiment. In this embodiment, the command line is divided into two parts, the header block 41 and the command block 42 during one display timing. This header block 41 corresponds to the so-called header information such as the CHECK SUM used for version information, noise check, and the like, and the auto increment ID. In this embodiment, the header block 41 has a fixed length. On the other hand, the instruction block 42 is composed of a set of two dots, and expresses one instruction in units of two dots. This first dot contains the ID number that executes the command, the command number, whether the command is constant, and whether the ID command is valid (enabled), and the next second dot is the command of the first dot. It stores the data value corresponding to. When the beginning of the command line is referred to as the 0th dot, in the command block 42, an even dot is arranged to place a command corresponding to the first dot, and an odd dot is arranged to its value corresponding to the second dot.

In addition, at present, 6-bit digital interfaces are mainstream, and when 8-bit digital interfaces are considered, it is preferable not to use LSB (least significant bit) 2 bits, and LSB 2 bits are reserved in this embodiment. . In addition, since there are three types of data of red (R), green (G), and blue (B) for each dot of the display, the command information is used for each dot using 18 bits of maximum 6 x 3 in one dot. It is possible to express. In addition, in this embodiment, the 0th-15th dot of the command line is used as the header block 41, and after the 16th dot is used as the command block 42. FIG. In addition, unused portions are reserved for either block.

In addition, in the present embodiment, different display screens can be displayed on a plurality of display panels by an interface using this command line, and a format based on this concept is called MDA (Multiple Display Architecture).

Here, in the present embodiment, the header block 41 is composed of the following items.

(1) Name (MDA id with MDA on valid) (1 dot)

(2) Version information (1 dot)

(3) Horizontal resolution (1 dot)

(4) Vertical reso1ution (1 dot)

(5) Auto increment ID (1 dot)

(6) MDA command line enable (1 dot)

(7) MDA command line total number (1 dot)

(8) Check sum of MDA line (1 dot)

(9) Test mode enable (1 dot)

(10) Reserve (7 dots)

The name (1), which is the first one dot of the header block 41, indicates that this format is MDA, and is used to check whether the MDA command line is valid or invalid. The following (2) version information is used when the MDA format is changed, and (3) horizontal resolution and (4) vertical resolution display the resolution of 1024 x 768 in this embodiment. (5) The auto increment ID is a value that automatically increases each time the display panel 2 (1) to 2 (n) connected in a chained state on the personal computer 1 side passes, and each display panel has its own value. You don't need to set any special IDs to have them automatically. By this auto increment ID, even if it loses its ID information in the initial stage, such as OFF / ON time of a power supply, it becomes possible to recognize self ID automatically by receiving an MDA format.

(6) The MDA command line valid / invalid instruction is used for protection when updating the MDA command line and the like. When the data on a digital signal that is connected in series is converted from parallel to serial data, the data is subject to the following delay. This is to prevent error transmission of the information, and the information has automatic time limit. (7) The total number of MDA instructions is used to increase the MDA instruction line. The MDA instruction line is not limited to one line as in the present embodiment, but the chain instruction information can be sent by increasing the number of lines as necessary. . (8) The MDA instruction total is a check that adds a check that the information is correct or does not change due to noise on the command line. In the chain connection state, noise is likely to occur and data is easy to change. In form it is especially valid. For the following (9) Test mode enable / disable, a test item can be entered by setting this bit, for example, it can be used for confirming a connection or the like. The following (10) is a spare part.

4 shows an example of data insertion into the first 0 dots and 1 dot in the head block 41. For example, a header block composed of the above items contains a value as shown in FIG. As the above-mentioned (1) name, the upper two bits (two bits in the most significant bit (MSB)) and the lower four bits thereof are used for the zero dot on the left side of Fig. 4, respectively, as M (2Dh). ), D (24h) and A (21h) are written. 4, version information using R, G, and B data as the (2) version information is written in one dot on the right side.

Next, the instruction block 42 in the present embodiment will be described. In the instruction block 42 following the header block 41, for example, the following items are described.

(1) Brightness contro1

(2) Contrast Contro1

(3) Gamma control (Gamma contro1)

(4) White balance

(5) Power save mode-Backlight off and LCD logic off

(6) Screen information maintenance and screen information refresh (Freeze and Refresh)

(7) Display disable / enable, blue back

(8) Expansion ratio (H / V)

(9) to (12) Start position and end position (horizontal / vertical) with built-in input data

(Start (End) position of image H (V) written in frame memory)

(13) to (16) LCD display start (end) position (horizontal / vertical)

(Display start (end) position H (V) in UXGA (SXGA, XGA) screen)

(17) Valid / invalid frame part remaining (Border color)

(18) Four SVGAs Displayed in UXGA (Four SVGA to UXGA)

(1) luminance control and (2) contrast control, which are the first items of the command block 42, are for adjusting and controlling the luminance and contrast of the display panels 2 (1) to 2 (n) that perform display operations. (3) Gamma control is for applying a reference voltage to the LCD according to the r correction curve for input / output adjustment. In addition, (4) white adjustment is a white point adjustment value which determines a hue level, and (5) power saving mode is an item regarding setting of a power saving mode, such as a backlight off and an LCD circuit power supply off. In addition, (6) screen information maintenance and screen information update indicate a time not to be received even if an MDA command is provided, and (7) display enable / disable (invalid viewing) means that a black and blue display itself is appropriate when an inappropriate signal is received. (8) The enlarged display ratio indicates the enlargement ratio in the horizontal and vertical directions. In addition, (9) to (12) input data embedding start position and end position are registers which set which part of the data sent from the display device are received, and (13) to (16) display start on LCD ( End) is a register that sets where and where received data is displayed on the LCD. (17) The remaining frame portion, valid / invalid, sets whether or not to color the remaining portions when displaying a resolution such as VGA (Videographics Array) (640 × 480) on XGA (1024 × 768). Is a register.

(18) Displaying four SVGAs on UXGA is a register used to display UXGA (1600x1200) with input data of SVGA (superVGA) (800x600).

5 shows an example of inserting an instruction into the instruction block 42. In this embodiment, as shown in Fig. 5, one command is composed of two dots, the first dot (2n dot) indicates the command, and the next dot (2n + 1 dot) describes the parameter. In the example of FIG. 5, the first bit in the MSB of the R data indicates whether the command is enabled (Valid or Invalid), and the next bit indicates that the command is assigned to each display panel 2 (1) to 2 (n). It shows whether it is common or unique to each display panel (Common or Unique). This bit command (ComInon or Unique) is an effective command for displaying and outputting the same image in each of the plurality of display panels 2 (1) to 2 (n). Next, an ID command is formed by the lower bits and the G data, and up to 256 display panels can be selected by 8 bits of ID7 to ID0. In the next B data MSB, 6 bits indicate where data is to be given in the display register, and indicate an internal register address in the control circuit 23 of the display panels 2 (1) to 2 (n) shown in FIG. have.

A value corresponding to an instruction of 2 n dots is stored in the 2n + 1 dot, which is the next dot shown in FIG. In other words, a display panel having an ID designated as 2n dots is used to describe data of what is performed on the designated internal register address. This 2n + is made by using all the upper 6 bits of each of the R, G, and B data. The actual display is performed on the display panels 2 (1) to 2 (n) based on the data of one dot. For example, if the instruction indicates the display start position on the LCD (13) described above, the contents of the data stored in the internal register by these 2n and 2n + 1 dots are used as the start position at the display position on the LCD.

As mentioned above, the flow which shows screen information on the display panel of NO.3 using the MDA format which employ | adopted the header block 41 and the command block 42 in the command line 32 is mainly shown in FIG. It demonstrates using a block diagram.

First, the display control circuit 15 in the personal computer 1 is controlled by a program executed in the CPU 11 and generates a command line 32 following the screen information. In the command line generated at this time, 1 is set to (5) Auto increment ID of the header block 41. Further, 3 is set to ID of the 2 n dot instruction in the instruction block 42, and 6 (Freeze and Refresh) is set to A5 to A0. The content of the data in the 2n + 1 dot is set to, for example, 1 (Refresh: Rewrite when 1).

The content of the (5) auto increment ID of the header block 41 transmitted from the control circuit 23 in the display panel 2 (1) having received the command line 32 by the digital receiver 21 as the screen information. Recognizes that its ID is 1. In addition, since the ID in the instruction block 42 is 3, it is recognized that it is not an instruction for itself and does not embed data or the like and operates only as a function of the buffer using the frame memory 24. In addition, for the next display panel [2 (2)] to be chained, 2 is set by +1 to (5) auto increment ID of the header block 41, and the command line (like the screen information from the digital transmitter 22) is set. 32).

Similarly, in the display panel 2 (2) having received the command line 32 by the digital receiver 21 as in the screen information, the content of the (5) auto increment ID of the header block 41 transmitted from the control circuit 23 is shown. Recognizes that its ID is 2. In addition, it is recognized that the ID in the instruction block 42 is not an instruction of itself, and it does not receive data or the like and operates in the function of a buffer using the frame memory 24. In addition, 3 (+1) auto increment ID of the header block 41 is set for the next display panel 2 (3) which is not shown in the chain, and the digital transmitter 22 shows screen information as shown in FIG. Send the command line 32.

Next, in the display panel 2 (3) having received the command line 32 by the digital receiver 21 as shown in the screen information, the (5) automatic of the on header block 41 transmitted from the control circuit 23 is obtained. It is recognized that the ID of the self is 3 by the content of the increment ID. In addition, since the ID in the command block 42 is 3, it is recognized as a command to the self, and according to the content of the command, a refresh, that is, data or the like is received, and the control by the liquid crystal display control circuit 25 controls the liquid crystal display circuit ( 26) to execute the display. Of course, it also functions as a buffer. Also, for the next display panel [2 (4), which is not shown in the figure, 4 +1 is set to (5) Auto Increment ID of the header block 41, and the screen information from the digital transmitter 22 is set as shown. Send the command line 32.

The display panel 2 (4) sees the contents of the transmitted header block 41 to recognize that its ID is 4, and sets +1 to 5 for the next panel. In addition, since the ID in the instruction block 42 is 3, it is recognized that it is not an instruction of its own, and operates only as a function of the buffer without incorporating data or the like.

As described above, control by the MDA format is performed on the display panels [2 (1) to 2 (n)] connected in series by the flow of ID.

Fig. 6 shows an enlarged display application using the MDA format in the present embodiment. In Fig. 6, reference numeral 51 denotes a video card, which stores a driving program using a so-called MDA format in which the video driver software is changed to add an unused display timing to a display for one line at the end of the original display screen. It is inserted into a PC and functions as a drive device of a display panel. 52 is a display panel displaying screen information by a single panel. In addition, 53 is a first display panel group, and the display panel 53 (1) constituting the first display panel group 53 enables the enlarged display by four display panels. It is connected to the chain. In addition, 54 is a 2nd display panel group, 9 display panels enable enlarged display, and the display panel 54 (1) which comprises this 2nd display panel group 54 is a 1st display panel group. It is connected to the display panel 53 (4) which forms the 53. As shown in FIG.

In the present embodiment, the plurality of display panels forming the first display panel group 53 and the second display panel group 54 each have the same XGA (1024 x 768) resolution as the display panel 52. Have In addition, the display panel 52, the first display panel group 53, and the second display panel group 54 are connected in series, and a plurality of display panels constituting each display panel group are also connected in the present embodiment. Is in a state of being.

As shown in Fig. 6, the same screen information is sent out to all the display panels on the cascaded bus. At this time, the display panel 52 outputs the input screen information as it is, but in each display panel constituting the first display panel group 53, the screen information is divided into quarters and held as each frame memory. The large screen is formed by enlarging and displaying the screen information. Similarly, in each display panel constituting the second display panel group 54, screen information is divided into 1/9 and held as each frame memory, and the large screen is formed by enlarging and displaying the held screen information. The operation of each of these frame memories is controlled based on the command information described in the above-described MDA format, so that enlarged display using a plurality of display panels can be performed with a simple configuration without changing hardware or increasing the number of lines of interface lines. Can be.

Second embodiment

In the first embodiment, as shown in Fig. 2, the command line 32 is formed on the 769 line next to the 768 lines in the display area 31 having the XGA display resolution (1024 x 768). The present embodiment inserts an instruction using blanking for each line.

In addition, about the component similar to 1st Embodiment, the same code | symbol as 1st Embodiment is attached | subjected and the detailed description is abbreviate | omitted here.

As shown in Fig. 7, the present embodiment provides a command area 61 in addition to the display time present in the scanning direction of the formed display area 31, and inserts a control command of the display panel that is connected in series with the command area. Doing. Specifically, as shown in Fig. 8, a blanking area of 320 dots exists between the n line screen information 62 formed of 1024 dots and the n + 1 line screen information 63, but this blanking is present. It is possible to write the control command 65 in 64 to add the control command information to the screen information as in the command line of the first embodiment. The contents of this control command 65 constitute the same header block 41 and command block 42 as in the first embodiment by using a plurality of blankings formed between the lines, and in the same manner as in the first embodiment, the chain connection MDA format can be developed for implementation.

As described above, according to the first and second embodiments, it is not necessary to construct new hardware when connecting a plurality of display apparatuses (display panels) to the PC apparatus, and command information is sent to the connected display panels. It is thereby possible to perform display operations on any display panel.

In addition, an enlarged display using a plurality of display panels continuously connected by simple software change can be easily performed.

Moreover, since the display information holding function is provided on each display panel side, it is not necessary to resend the screen information of the same image limit. Therefore, since data values on the cascaded bus do not have a change point and have no change point except when updating the screen information, the occurrence of EMI (electromagnetic interference) can be suppressed in advance.

Incidentally, the present embodiments (1 and 2) have been described using LCD as the display device. When the large screen is generated by the chain connection, the LCD is excellent in that the connection is easy for each screen, but the present invention is not limited to such LCD, but includes a display of a light emitting type such as a CRT, and is also applicable to other electronic displays. can do.

In addition, in the present embodiment, the header block and the command block have been clearly divided and described using the MDA format as one example, but the present invention does not necessarily need to be clearly divided in this manner, and the contents thereof are provided as a function. Of course, it is a matter to be chosen arbitrarily.

As described above, according to the present invention, it is possible to chain-connect more display devices in a state in which the physical limitations from the respective devices are removed, thereby facilitating expansion.

Claims (16)

In the driving method for driving a plurality of chain display device, Adding a display timing not displayed in the display area to the display timing visualized in the display area of the display device; Writing a control command to control the display device at the added display timing, And the control command includes selection information for selecting a display device from a plurality of serial display devices and control information for the selected display device. The method of claim 1, wherein the display timing that is not displayed in the display area of the display device is a timing for forming at least one line formed after the last line of the display area. The display according to claim 1 or 2, wherein the control command comprises a command line including a header block portion and a command block portion, wherein the header block portion is a block including header information necessary for concatenating display devices. Method of driving the device. The method according to claim 1, wherein the same screen information is transmitted to a plurality of display devices for constructing a large screen by the enlarged display, The selection information includes selection information for selecting all of a plurality of display devices for constituting a large screen by an enlarged display, The control information driving method of the display device characterized in that the display information is divided and displayed on the display device constituting a large screen. In the driving method for driving a plurality of chain display device, Adding a display timing not displayed in the display area to a display timing visible to the display area of the display device; Writing a control command to control the display device at the added display timing, And the control command includes ID information updated each time it passes through a plurality of serial display devices. The display apparatus of claim 5, wherein the display apparatus recognizes its own ID based on the ID information and executes the display operation according to the indication information of the ID executing the display operation included in the control command. Method of driving a display device. In the drive device for driving a plurality of chain display device, Image signal generating means for generating an image signal for displaying an image in a display area of the display device; Chain display signal generating means for generating a chain display signal by applying a display timing which is not used to image display the display area based on the generated video signal; And an output means for adding the chain display signal generated by the chain display signal generating means to the video signal generated by the video signal generating means, and outputting the chain display signal to any chained display device. A drive device for a display device. 8. The method according to claim 7, wherein the chain display signal generated by the chain display signal generating means is a chain display signal using timing of at least one line not used for image display of the display area based on the generated image signal. A drive device for a display device, characterized in that. 8. The method of claim 7, wherein the chain display signal generated by the chain display signal generating means includes selection information for selecting a display device from a plurality of chain display devices and control information for controlling the selected display device. The driving device of the display device. 8. The method according to claim 7, wherein the chain display signal generated by the chain display signal generating means includes selection information for selecting all of the plurality of chain display apparatuses, so that the plurality of the same image signal generated by the image signal generating means is generated. And a serial transmission to the serial display device of the display device. The display apparatus according to claim 10, wherein the concatenated display signal includes control information for separately dividing the image signals with respect to the plurality of display apparatuses, and for enlarging and displaying the divided image signals on the display apparatus. Drive of the device. A display apparatus connectable to a display driving apparatus for outputting a control command to control an image signal for displaying on a display apparatus to be connected and a display apparatus to be connected, the display apparatus comprising: A digital receiver for inputting a control command formed at the video signal output from the display driving device and a display timing that is not displayed in addition to the video signal; A control circuit for interpreting a control command input by the digital receiver; A frame memory for storing the video signal; And a digital transmitter for outputting the video signal and a control command added to the video signal to a connected display device. The method of claim 12, wherein the control command includes ID information that is updated each time the display device passes through the display device. The control circuit updates the ID information included in the control command input by the digital receiver, And the digital transmitter outputs the ID information updated by the control circuit to a next display device connected thereto. The display apparatus according to claim 13, wherein the control circuit recognizes its own ID based on the updated ID information, and compares the recognized own ID with ID indication information included in the control command. . The apparatus of claim 12, wherein the control circuit determines whether to display the video signal on its display device by an interpreted control command, And the digital transmitter outputs the video signal and the control command to a next display device, irrespective of whether or not to display the video signal made by the control circuit. A display driving device for outputting a video signal displayed on an image for the display area and a serial display signal added to the video signal and using timing of at least one line not used for video display; A first display device connected to the display driving device to input the video signal and the chain display signal, interpret the chain display signal, and display an image on its own display area based on the video signal Wow, Connected to the first display device, and inputs a video signal displayed on the display area and a chain display signal using the timing of at least one line which is added to the video signal and not used for the video display, and the chain display signal And a second display device which enables to display an image on its own display area based on the video signal.