JP2002366082A - Display device and information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recover an error in data transfer from an information processor to a display device without leaving over the error as display in the display device. SOLUTION: A host device 100 transmits error checking information for checking an error to a display device 300 by adding it to packet data. The display control part 8 of the display device 300 receives the packet data and detects an error by using the error checking information. Moreover, when an error is detected, the display control part 8 outputs the request of the retransmission of the packet data to the host device 100. Then, the device 100 receives the request of the retransmission and retransmits the packet data in which the error is generated to the display control part 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device,
In particular, the present invention relates to a display device having a digital interface connected to a PC (personal computer), WS, or the like.

[0002]

2. Description of the Related Art Conventionally, a display image is processed by a graphic controller of a host device such as a personal computer (PC) and transferred to a display device. In recent years, this display device has made progress beyond the processing capability of a host device. For example, in an LCD, a conventional XGA
(1024 x 768 dots), SXGA (1280 x 1
024 dots) and UXGA (1600 × 1200) to QXGA (2048 × 1536)
Dots), QSXGA (2560 x 2048 dots),
Ultra-high definition panels such as QUXGA (3200 × 2400) are being put to practical use. On the other hand, the performance of the graphic controller of a general PC is limited to about QXGA, and about VGA for moving images.

[0003] In recent years, as a LCD panel, a "multi-panel" in which a plurality of panels are combined into one panel has been put into practical use, and higher definition has been made possible.

Further, when transferring display data corresponding to ultra-high definition, it is necessary to increase the transfer rate as the definition becomes higher.
fferential Signaling), TMDS (Transition Minim
GVIF (Gigabit V)
Digital interfaces using a low voltage differential method, such as video interface (ideo interface), are becoming widespread. By increasing the number of these signal lines, it is possible to cope with the higher definition.
Also, Digital Link: High-Functional Digital Monit
or Interface (Japan IBM, SID'99Digests
As described in t), a method of transferring a specific window area, which is an area where display data is updated, with a parameter such as a display position added thereto is also being studied.

[0005]

However, in the prior art, since data transfer is performed by adding a parameter only to a specific display area, if a transfer error occurs in the display data, the display data in which the error has occurred is lost. It may remain on the display. Further, when an error occurs in a parameter, a situation may not be displayed at all.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a display device and an information processing device in which, when an error occurs during transfer of packet data from a host device to a display device, the transfer error does not affect display.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an information processing apparatus as a host apparatus transmits error check information for checking an error in a transmission means to a packet data. And send it. The display device includes a display control unit including a display control unit that performs display control according to packet data including display data from the host device, and a display unit for displaying an image. The error detection means of the display control unit receives the packet data to which error check information for checking an error is added, which is sent from the host device, and detects an error based on the error check information. Output means, when an error is detected by the error detection means,
A request for retransmission of the packet data is output to the host device. The receiving means of the information processing apparatus, which is the host apparatus, receives a retransmission request for the packet data in which an error has occurred from the display device, and the control means transmits the packet data when the receiving means receives the retransmission request. The retransmission is controlled by means.

According to the present invention, even if an error occurs during the transfer of packet data from the host device to the display device, the display device detects the error, requests retransmission of the packet data, and accepts the retransmitted packet data. Therefore, the display data in which an error has occurred is not displayed, and the transfer error does not affect the display.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a configuration diagram of a liquid crystal display device 300 according to an embodiment of the present invention. 1, a liquid crystal display device 300 includes a liquid crystal panel 20 for displaying an image and a display unit 200 including driving units 16 and 18.
A display control unit 8 for displaying, on the display unit 200, packet data to which display data of a screen area to be updated transmitted from the host device 100, control parameters, and error check information for checking errors are added. ,
A screen storage unit 14 capable of storing image information for at least one screen of the liquid crystal panel. In the present embodiment, a description will be given below assuming that the screen storage unit 14 stores display data for one screen of the liquid crystal panel 20.

In the present embodiment, the host device 10
The display device receives the packet data to which the display data of the screen area to be updated transmitted by 0, the control parameter and the error check information for checking the error are added, and an error occurs based on the error check information. It is determined whether or not there is an error, and when an error occurs, retransmission of the packet data is requested, and the display data of the packet data in which the error has occurred is not updated.

The display control unit 8 includes a vertical synchronization signal 1 as a vertical synchronization signal line, a horizontal synchronization signal 2 as a horizontal synchronization signal line, a data valid signal 3 indicating data validity, and a display. The display data 4 of information and the synchronous clock 5 which is a synchronous signal line are received from the host device 100. The vertical synchronizing signal 1 is a signal of one display cycle, the horizontal synchronizing signal 2 is a signal of one horizontal cycle, and the data valid signal 3 is a signal indicating a period during which the display data 4 is valid. Is done. In this embodiment, there are two types of display data: a case where one screen is transferred in a raster scan format as in the past (conventional mode), and a case where only the display update portion is packetized and transferred (packet mode). Description will be made below assuming that there are types. The display control unit 8
The communication data 6, which is a bidirectional data line for receiving information such as the mode of display data from the host device 100 and transmitting display resolution and data transfer error information from the display side, The communication clock 7 of the signal line is connected. In the present embodiment, the communication data 6 and the communication clock 7 are DDC (Display Data Channel).
nel) format.

The display control unit 8 determines whether the display data 4 is the conventional mode or the packet mode based on the data of the communication data 6, and in the case of the conventional mode, converts the display data 4 according to the resolution of the liquid crystal panel. A storage / read command signal 11 for temporarily storing in the screen storage means 14;
A read address 12 and storage data 13 are generated.
The display control unit 8 generates a storage / read command signal 11 and a storage / read address 12 so as to read display data for one screen in accordance with the display timing of the liquid crystal panel. The screen storage means 14 stores the storage / read command 1
1 and the storage data 1 according to the storage / read address.
3 or the screen read data 15 is read. Further, the display control unit 8 obtains a data line driving signal 9 and a scanning line driving signal 10 from the screen read data 15.
Generate

When the display data 4 is in the packet mode, the display control unit 8 determines whether or not an error has occurred in the received display data 4. A storage / read command signal 11 and a storage / read address 12 for storing in the screen storage means 14 so as to be written at a designated display position on the liquid crystal panel according to the parameters such as the display position and the enlargement ratio included.
And the storage data 13 is generated. Further, similarly to the conventional mode, the storage / read command signal 11 and the storage / read address 12 are generated so that display data for one screen is read in accordance with the display timing of the liquid crystal panel.
The screen storage means 14 stores the storage data 13 or reads the screen read data 15 in the packet mode in accordance with the storage / read command 11 and the storage / read address as in the conventional mode. Display control unit 8
Generates a data line driving signal 9 and a scanning line driving signal 10 from the screen read data 15. Details of the generation of the data line driving signal 9 and the scanning line driving signal 10 will be described later.

The display section 200 has a liquid crystal panel 20, a data line driving means 16, a data line driving signal 17, a scanning line driving means 18, and a scanning line driving signal 19.

In the present embodiment, the liquid crystal panel 20
The following description is based on the assumption that the pixel has a resolution of 280 × 1024 dots.

FIG. 2 shows an internal configuration diagram of the display control unit 8 shown in FIG.

In FIG. 2, a display control unit 8 includes a communication control unit 21 for transmitting and receiving communication data to and from a host device, an error detecting unit for inputting display data and detecting an error, and a host device for detecting an error. Output means for outputting a retransmission request for the packet data to the input control unit 2
5, an enlargement control unit 32 for controlling the enlargement of display data, a storage control unit 35 for controlling storage / readout to the screen storage means 14, and a liquid crystal display signal generation unit 38 for generating a display signal to be displayed on the liquid crystal. Have.

The communication control unit 21 uses control parameters required by the input control unit 25, the enlargement control unit 32, the storage control unit 35, and the liquid crystal display signal generation unit 38 as parameter data 22 as a predetermined parameter type. Is added, and output at the timing of the parameter write strobe 24 indicating the timing of reading the parameter. In the present embodiment, the following description will be made on the assumption that the enlargement ratio of the display data in the packet mode and the conventional mode and information on the position where the display data is to be displayed are included in the control parameters. Further, the communication control unit 21 outputs the error information output control signal 3 when the input control unit 25 receives an error when the display data 4 is received.
1 and transfers the error occurrence to the host device 100 via the communication data 6.

The input control unit 25 has a parameter address 2
3, a data transfer mode signal 28 indicating whether the display data is in the packet mode or the conventional mode, and determines whether or not the parameter data 22 is a parameter required by itself and the enlargement control unit 32; A data enlargement ratio 29 indicating a data enlargement ratio and a data display position 30 indicating a data display area are output. When the data transfer mode signal 28 is "1", the display data transfer mode is the packet mode, and the information on the enlargement ratio of the display data and the position where the display data should be displayed in the packet mode is packetized into the display data 4. ing. It is assumed that the display data transfer mode is the conventional mode when the data transfer mode signal 28 is "0". Further, the input control unit 25 detects whether or not a transfer error exists in the display data 4, and
When an error exists, information for transferring the type and position of the error to the host device 100 via the communication control unit 21 is output as an error information output control signal 31,
In order to control subsequent data processing when an error occurs, an error-processed data valid signal 26 indicating valid data after error processing, and error-processed display data that is display data after error processing. 27 is output.

In the conventional mode, the enlargement control unit 32
From the vertical synchronization signal 1, the horizontal synchronization signal 2, the post-error data valid signal 26, the post-error display data 27, the synchronization clock 5 and the storage timing signal 36, the enlarged display data 33, which is the display data after enlargement, and the enlarged display data 33 An enlarged display data address 34 indicating the display position is generated. In the packet mode, the data valid signal after error processing 2
6. The enlarged display data 33 and the enlarged display data address 34 are generated from the display data 27 after error processing, the synchronous clock 5, and the storage timing signal 36.

The storage controller 35 generates the storage / read command 11 and the storage / read address 12 so as to output the liquid crystal panel display data 37 in accordance with the display timing of the liquid crystal panel 20. In order to read the screen read data 15 and store the enlarged display data 33 at an address according to the enlarged display data address 34, a storage / read command 11, a storage / read address 12, and a storage data 13 are generated.

The liquid crystal display signal generating section 38 operates from the liquid crystal panel display data 37, the data line driving signal 9 including the data timing signal for operating the data line driving section 16, and the scanning line driving section 18 operates. And a scanning line driving signal 10 including a timing signal. In the present embodiment, the parameter from the communication control unit 21 is not required in the liquid crystal display signal generation unit 38.

Next, the hardware configuration of the host device 100 will be described with reference to FIG.

Referring to FIG. 17, a host device 100 is an information processing device such as a personal computer, and is connected to a CPU 402 for controlling, a memory 410 of a storage means, an input unit 411 for receiving an instruction, and a liquid crystal display device 300. Interface section 401. CPU4
02 executes processing specified by a software program stored in the memory 410. The CPU 402 processes display control for display data and parameter creation according to the present embodiment in accordance with a software program. However, the CPU 402 may further include a graphic controller so that the display control is performed by the graphic controller. The memory 410 functions as a work area of the CPU 402 or functions as a storage unit for storing a software program or an OS that defines an operation procedure of the CPU 402. It is also used as a buffer for temporarily storing display data. The input unit 411 is connected to a mouse, a keyboard, and the like, and receives an instruction from a user.
The interface unit 401 is connected to the liquid crystal display device 300, and includes a vertical synchronization signal 1 which is a vertical synchronization signal line;
A horizontal synchronization signal 2, which is a horizontal synchronization signal line, a data valid signal 3, which indicates data validity, display data 4 of display information, and a synchronization clock 5, which is a synchronization signal line, are transmitted. Also, the interface unit 401 transmits communication data 6 which is a bidirectional data line for transmitting information such as the mode of display data and receiving display resolution and data transfer error information from the display side. The communication clock 7 of the signal line is connected. The CPU 402 of the host device 100 controls transmission and reception of each signal transmitted and received by the interface unit 401. In the present embodiment,
Packet data to which error check information is added together with information indicating whether the mode is the conventional mode or the packet mode is transmitted via the interface unit 401, a request for retransmission of the packet data is received, and the packet data in which an error has occurred is retransmitted. It is controlled to be.

FIG. 3 is an explanatory diagram of the data format of the data valid signal 3 and the display data 4 transmitted from the host device 100.

In FIG. 3, reference numeral 39 denotes a first packet;
Is a second packet, and 41 is a third packet. The packet becomes valid data while the data valid signal 3 is "1". The names are for convenience only. The packet includes a head signal 42 indicating the head of the packet, a main signal 43 of the data part, and an end signal 44 indicating the end of the packet. The head signal 42 includes packet start information 45, a data ID 46 indicating a window number,
A main signal type 47 indicating whether the data is a parameter or display data, a main signal address 48 indicating the upper left coordinate position (X, Y) of the block when the data is display data, and error check information 49 are provided.

In the present embodiment, in order to make the packet length the same, one packet includes 16 bits × 16 bits of window display data (hereinafter referred to as one block).
The display data of the minute area is included. By transferring display data for each 16 × 16 dot area, the processing can be simplified since the packet length does not change depending on the size of the window. The position of the block is indicated by this signal address 48, and the same data ID 46 is used for each block in one screen or one window.
Indicated by Alternatively, the window display data 54 is
As the variable length, all display data in the window may be transferred. The packet start information 45 is a signal indicating the start of a packet. In the present embodiment, when transferring as packet data for each block of the window area having the same data ID, the packet start information 45 indicates the head of the first packet. . The main signal type 47 indicates whether the main signal 43 is the parameter described above or the display data. The error check information 49 is an error check bit for detecting a difference between when receiving data and when transmitting from the host as an error.

The signal 43 may indicate a window parameter or display data. For example, window parameters can be transferred in the first packet 39, and display data can be transferred in the second packet 40 and thereafter. In the case of a parameter, this signal 43 indicates a window horizontal start position 50 indicating the horizontal start position of the display position, a window vertical start position 51 indicating the vertical start position of the display position, and a window enlargement ratio. A window enlargement ratio 52 and a main signal error check bit 5 for checking an error in the main signal.
3 is provided. In the case of display data, the main signal 43 includes window display data 54 which is display data in a window, and a main signal error check bit 53 for checking an error in the main signal.

The window horizontal start position 50 is
The horizontal start position of the window indicated by the data ID 46 is shown. The window vertical start position 51 is
Indicates the starting position in the vertical direction. Window magnification 52
Indicates an enlargement ratio when enlarged display is performed. Also, in the case of display data, there is provided error check information 53 for detecting a difference between the data reception and the transmission at the time of transmission by the host 100 as an error.

In this embodiment, by adding error check information to each of predetermined areas of the head signal 42 and the main signal 43, errors of the respective signals are detected, and an error occurs. A retransmission request has been made for packet data. Further, the subsequent error processing / error recovery method is changed depending on the error occurrence position. For example, if the head signal is an error, the packet data is discarded because there is an error in the present signal type, the present signal address, and the like, and a retransmission request is made without performing the subsequent processing. When the error check bit 53 of the signal 43 is an error, there are a parameter data type and a display data type.
All the packet data having the same data ID as that of the packet data in which the error has occurred is discarded, and a retransmission request of the packet data having the data ID is made. In the case of a display data error, since there is no error in the head signal, a retransmission request is made and the packet data is processed as it is. By judging the error position, the processing can be made different in accordance with the error position, and by having it retransmitted, error-free packet data can be displayed.

In this embodiment, an error check bit is added for each predetermined area. However, one error check bit may be added to packet data.

Hereinafter, the main signal of the first packet 39 will be described as a parameter, and the main signal of the second packet 40 and the third packet 41 will be described as display data.

FIG. 4 is a conceptual diagram of a window and a packet in the present embodiment. In FIG. 4, 55 is an entire screen, 56 is a window area, 57 is a window area start position, 58 is a packet area, and 59 is a packet area start position. The entire screen 55 has a resolution of 1280 × 1024 dots in the present embodiment, and has a window area 56 therein. When the display data of the window area 56 is transferred, the window area is divided into blocks of 16 dots × 16 dots, and each block is transferred as packet data. In FIG. 4, the packet is divided into 20 pieces of packet data, the packet data in the packet area 58 is transmitted with start information indicating that it is the first packet, and the same size packet with the same ID is added 20 times. Forward. Window area start position 5
The coordinates of 7 correspond to the window horizontal start position 50 and the window vertical start position 51 in FIG. 3, and the coordinates of the packet area start position 59 correspond to the main signal address 48 in FIG. That is, the upper left coordinate of each block is indicated by the main signal address 48.

FIG. 5 shows an internal configuration diagram of the input control unit 25 shown in FIG. In FIG. 5, the input control unit 25
Is a parameter storage unit 6 for detecting and storing parameters.
0, a packet counting control unit 68 for detecting a packet having the same ID, a packet counting unit 72, and an error information generating unit 7.
4, an error information storage means 78, an error information output control means 80, a parameter separating means 63, a data enlargement ratio selector 66, and a data display position selector 67.

The parameter storage section 60 stores the communication control section 21
From the input control unit 25
Then, the display data transfer mode (indicating the conventional mode or the packet mode) required by the enlargement control unit 32, the enlargement ratio of the display data in the conventional mode, and the data display position in the conventional mode are determined. And outputs the data as the data transfer mode signal 28, the conventional mode data enlargement ratio 61, and the conventional mode data display position 62, respectively. The parameter separating means 63 separates the data enlargement ratio in the packet mode and the data display position in the packet mode included in the display data 4 from the packet data, and the packet mode data enlargement ratio 64 and the packet mode data display position 65 respectively. Output as The data enlargement ratio selector 66 selects and outputs the conventional mode data enlargement ratio 61 when the data transfer mode signal 28 is "0" and indicates the conventional mode according to the data transfer mode signal 28, and when the data transfer mode signal is "1". When the packet mode is indicated, the packet mode data enlargement ratio 64 is selectively output. Similarly, the data display position selector 67 selectively outputs the conventional mode data display position 62 when indicating the conventional mode and selectively outputs the packet mode data display position 65 when indicating the packet mode according to the data transfer mode signal 28. The packet counting control unit 68 packetizes a start signal 69 indicating the beginning of the packet data of the same data ID and data ID information 70 that sets data belonging to the same display window to the same ID. A packet counting clock 71 is generated from the display data 4 and counts the number of packets from the data valid signal 3. Further, the packet counting control unit 68 operates only in the packet mode according to the data transfer mode signal 28. The packet counting unit 72 starts counting by the start signal 69, counts the number of the packet transferred by data ID according to the data ID information 70 and the packet counting clock 71, and counts the packet count value 73. Output as In the present embodiment, the start signal 69 is reset and the packet counting clock 71
It operates as a counter using the clock as a clock. The error information generation unit 74 detects an error from the error check bits 49 and 53 packetized in the display data 4 and, when an error occurs, a data output control signal 75 for controlling the subsequent data processing, and the occurrence of the error. Error occurrence state information 76 including information indicating a state or an error occurrence position (indicating whether an error has occurred in any of a head signal, a main signal of a parameter, or a main signal of display data), and indicates that an error has occurred. An error occurrence signal 77 is generated. The error information generation unit 74 operates only in the packet mode according to the data transfer mode signal 28. The error information storage means 78, in accordance with the error occurrence signal 77, detects an error and, when an error is detected, the packet count value 73 indicating the packet number in which the error has occurred and the error occurrence state information 7
6 is stored. The error information output control means 80 controls the timing of outputting the error detection result and outputs the error information output control signal 31 to the communication control unit 21. The error information output control means 80 detects the end point of the packet data from the data valid signal 3 and sets it as the output timing. The error information output control means 80 operates only in the packet mode according to the data transfer mode signal 28. The data output control unit 82 outputs a data output control signal 75
, The display data output when an error occurs is controlled, and after the error processing, the error processing data valid signal 26 indicating that the data is valid, and the error processing display as the display data after the error processing. Output as data 27. Also, the data output control unit 82 operates only in the packet mode according to the data transfer mode signal 28.

FIG. 6 shows an internal configuration diagram of the packet counting control unit 68 shown in FIG.

In FIG. 6, the packet count control unit 68
Generates a start signal 69 indicating the beginning of packet data having the same data ID, and data ID information 70 having data belonging to the same display window as the same ID from the display data 4 in which these information are packetized. Then, a packet counting clock 71 for counting the number of packets is generated from the data valid signal 3. The start information decoder 83 outputs a start information decode signal 84 when the display data 4 is data indicating start information which is the first packet. In the present embodiment, “1” is set when the display data 4 matches the data indicating the start information.
Is output. The start information position determining means 85 determines the position where the start information is included in the packet from the data valid signal 3 and outputs it as a start information position signal 86. In the present embodiment, “1” is output at a position including start information. Start signal generating means 87
Outputs the start signal 69 according to the start information decode signal 84 and the start information position signal 86 when the display data 4 indicates the start information and is at a position including the start information. In the present embodiment, “1” is output when the display data 4 indicates the start information and is at a position including the start information. Data I
The D position determining means 88 determines the position including the data ID in the packet from the data valid signal 3 and outputs the position as the data ID position signal 89. In the present embodiment,
"1" is output at the position including the data ID. The data ID generation means 90 takes in the data ID included in the display data 4 according to the data ID position signal 89,
Output as data ID information 70. The packet counting clock generating means 91 outputs the start signal 69 and the data I
A packet counting clock 71 is generated from the data valid signal 3 so as to count the number of packets in accordance with the timing of the D information 70.

FIG. 7 shows the packet counting unit 7 shown in FIG.
2 shows an internal configuration diagram of FIG.

In FIG. 7, the packet counting section 72 starts counting in response to a start signal 69, and outputs data ID information 7
0 and the packet count clock 71, the data I
The number of the packet transferred for each D is counted and output as a packet count value 73. In this embodiment, in order to exemplify a case where two windows are on the same screen and packet data in each window is transferred in a mixed manner, a data ID
An example in which two determination units are provided. In this case, the data ID may indicate “1” or “2”. Data I
Three or more D determination units may be provided.

In FIG. 7, the data ID1 decoder 92
Generates a signal indicating when the data ID is 1 from the data ID information 70. In the present embodiment, the data ID is 1
"1" is output at the time of. Only when the data ID information 70 indicates the data ID 1, the data ID 1 packet counting means 94 counts the number of packets according to the packet counting clock 71 and outputs the data ID 1 packet count value 95. In the present embodiment, it operates as a counter that counts the data ID1 decode signal 93, resets the start signal 69, and uses the packet count clock 71 as a clock. Data ID2 decoder 96
Generates a signal indicating when the data ID is 2 from the data ID information 70. In the present embodiment, the data ID is 2
"1" is output at the time of. Only when the data ID information 70 indicates the data ID 2, the data ID 2 packet counting means 98 counts the number of packets according to the packet counting clock 71 and outputs the data ID 2 packet count value 99. In the present embodiment, it operates as a counter that counts the data ID2 decode signal 97, resets the start signal 69, and uses the packet count clock 71 as a clock. Packet count selector 10
0 indicates the data ID 1 packet count value 95 when the data ID information 70 indicates that the data ID is 1,
When the data ID is 2, the data ID 2
The packet count value 99 is selectively output.

FIG. 8 is a time chart for explaining the packet number counting operation in the packet counting control section 68 and the packet counting section 72.

In FIG. 8, 101 is the first packet start information, 102 is the first packet data ID, 103 is the first packet main signal, 104 is the second packet start information, 105 is the second packet data ID, and 106 is the first packet data ID. 2 packet main signal, 107 is third packet start information, 1
08 is the third packet data ID, 109 is the third packet main signal, 110 is the fourth packet start information, 111 is the fourth packet data ID, 112 is the fourth packet main signal, 113 is the fifth packet start information, 114 is Fifth
The packet data ID 115 is the fifth packet main signal, 1
16 is the sixth packet start information, 117 is the sixth packet data ID, and 118 is the sixth packet main signal. The description of the end signal described in FIG. 3 is omitted. In the present embodiment, the first packet start information 101
This is the head of the packet data of D1, and indicates that the fourth packet start information 110 is the head of the packet data of the data ID2. Also, the first packet data I
D102, second packet data ID 105, third packet data ID 108, and fifth packet data ID
114 is 1 and the fourth packet data I
It is assumed that the data ID of D111 and the sixth packet data ID 117 is 2.

In FIG. 8, when the start information decoder 83 of the packet counting control unit 68 shown in FIG. 6 decodes the start information 101 of the first packet, the start signal generation means 87 generates a start signal 69. Further, the data ID generation means 90 outputs “1” as the data ID information 70. Data ID1 packet counting means 94
Counts up when the data ID information 70 indicates the data ID 1 and outputs it as the data ID 1 packet count value 95. The data ID 1 packet counting means 94 also sequentially counts up the second packet and the third packet since the data ID information is 1. In the fourth packet, since the data ID is "2", when the start signal generating means 87 outputs the start signal 69, the data ID generating means 90 outputs "2" as the data ID information 70. The data ID2 packet counting means 98 is counting up.

FIG. 9 shows an internal configuration diagram of the error information generation unit 74 shown in FIG.

In FIG. 9, the error information generation unit 74
An error check information separating unit 119, an error detecting unit 121, a data counting unit 122, an error state determining unit 124, and a data output control signal generating unit 125 are provided. The error check bit separation means 119 separates the error check information portion packetized in the display data 4 and outputs it as error check information 120. The error detection unit 121 is configured to output the error check information 12
An error is detected from 0 and the display data 4 and output as an error occurrence signal 77. The data counting unit 122 counts the number of the synchronization clocks 5 during the valid period of the data valid signal 3 and outputs the data count value 122 in order to determine the position where the error has occurred. Error state determination means 1
24 determines the position where the error has occurred from the data count value 122 and outputs it as error occurrence state information 76. The data output control signal generation means 125 determines whether or not to output the display data 4 from the error occurrence state information 76 when an error occurs, and outputs the data output control signal 75
Output as In this embodiment, when the display data 4 is output, the data valid signal 3 is output as “1”, and when the display data 4 is not output to the subsequent stage due to an error, the data valid signal 3 is set to “0”. I do.

FIG. 10 shows an internal configuration diagram of the data output control unit 82 shown in FIG.

In FIG. 10, packet output control means 1
26 is a packet storage unit 128 described later according to the data transfer mode signal 28 and the data output control signal 75.
Output control signal 12 for controlling the output timing of
7 is generated. In this embodiment, when the data transfer mode signal 28 is “1”, the mode is the packet mode, and the data output control signal 75 is “1”, data is output from the packet storage unit 128. Packet storage means 128
Temporarily stores the input data valid signal 3 and display data 4 and outputs them as storage means output data valid signal 129 and storage means output display data 130 in accordance with packet output control signal 127, respectively. The data valid signal selector 131 operates according to the data transfer mode signal 28.
Data valid signal 3 and storage means output data valid signal 129
And outputs either one. Display data selector 13
2 selects and outputs one of the display data 4 and the storage means output display data 130. In this embodiment, when the data mode signal 28 is "1" (packet mode), the storage unit output data valid signal 129 and the storage unit output display data 130 are output, and the data mode signal 28 is "0".
In the (conventional mode), the data valid signal 3 and the display data 4 are output.

FIG. 11 is a time chart for explaining an error state and a data output control operation in error information generation section 74 and data output control section 82.

In FIG. 11, 133 is the first packet head signal, 134 is the first packet main signal, and 135 is the second signal.
The packet head signal 136 is the second packet main signal, 13
7 is the third packet head signal, 138 is the third packet main signal, 139 is the fourth packet head signal, 140 is the fourth packet main signal, 141 is the fifth packet head signal, 142 is the fifth packet main signal, and 143 is 6th packet head signal,
144 indicates the sixth packet main signal. In FIG. 11, the data output signal 7 for the error occurrence state information 76 is shown.
5, a data valid signal after error detection 26 for the data output signal 75, and display data 27 after error detection. For explanation, start information and data ID described above
Are collectively represented as a head signal, and an end signal is omitted. In the present embodiment, a case where an error has occurred in a portion painted in gray, that is, in the third packet head signal 137, the fourth packet main signal 140, and the sixth packet head signal 143 is shown. If the head signal or the parameter is an error, the processing of the present signal will be hindered. Therefore, the data output control signal 75 is set to "0" to stop the processing of the packet in which the error has occurred.
, The data valid signal 26 after error detection and the display data 27 after error detection are not output. If the display data has an error, the data output control signal 75 is set to "1" to output a data valid signal 26 after error detection and display data 27 after error detection.

FIG. 12 shows another example of a time chart for explaining an error state and a data output control operation in the error information generation section 74 and the data output control section 82.

In FIG. 12, the first packet main signal 13
4, that is, an example in which an error has occurred during parameter transfer. In the present embodiment, in the case of a parameter error, the processing of this signal also hinders the processing. Therefore, in order to stop the processing of the packet in which the error has occurred, the data output control signal 75 is set to “0” and the data valid signal after error detection 26 and display data 27 after error detection are not output.

FIG. 13 shows the enlargement control unit 32 shown in FIG.
FIG.

In FIG. 13, the enlargement control section 32 includes a main signal separation section 145, a data enlargement processing section 149, and an address processing section 150. When the data transfer mode signal 28 is “1” indicating the packet mode, the signal separation unit 145 separates the head signal and the end signal from the present signal, and outputs a packet mode display valid signal 146 and packet mode display data 147. And a packet mode synchronization clock 148. When the data transfer mode signal 28 is “0” indicating the conventional mode, the data enlargement processing unit 149 enlarges the display from the vertical synchronization signal 1, the horizontal synchronization signal 2, the data valid signal 3, the display data 4 and the synchronization clock 5. Data 33 is generated, and the data transfer mode signal 28 is
When the packet mode is “1”, the packet mode display valid signal 146 and the packet mode display data 147
And the enlarged display data 33 is generated from the packet mode synchronous clock 148. When the data transfer mode signal 28 is “0” indicating the conventional mode, the address processing unit 150 generates an enlarged display data address 34 from the vertical synchronization signal 1, the horizontal synchronization signal 2 and the data valid signal 3, and performs data transfer. When the mode signal 28 is “1” indicating the packet mode, an enlarged display data address 34 is generated from the data enlargement ratio 29 and the data display position 30.

FIG. 14 is an explanatory diagram of the packet data separating operation in the signal separating section 145.

In FIG. 14, in the first packet 39, since this signal is a parameter, the packet mode display data 140 and the packet mode display valid signal 139 are not valid. Second packet 40 and third packet 41
Since this signal is the window display data 54, the packet mode display data 140 and the packet mode display valid signal 139 are valid only for that part. At this time, the part of the start signal 42 and the end signal 44 is not made effective.

FIG. 15 is an explanatory diagram for explaining the relationship between the screen readout data 15 and the display data 4 to the stored display data 13.

In FIG. 15, 151 is the first line read data, 152 is the first line retrace period, and 153 is the second line readout period.
Line read data 154 is a second line flyback period, which is readout data and a flyback period corresponding to raster scan of one line at a time according to the display timing of the conventional liquid crystal panel. 155 is the fourth packet data, 156
Is the fifth packet data, which is the packet data following the first packet data 39, the second packet data 40, and the third packet data 41 shown in FIG. In the present embodiment, in the fourth packet data 155 and the fifth packet data 156, the present signal is display data, like the second packet data 40 and the third packet data 41. 157 is the second packet display data and 158 is the third packet display data.
Packet display data, 159 is fourth packet display data, 160 is fifth packet display data,
The packet data 40, the third packet data 41, the fourth packet data 155, and the fifth packet data 156 correspond to the main signal portion. 161 is enlarged display data of the second packet, 162 is enlarged display data of the third packet, 163 is enlarged display data of the fourth packet, and 164 is enlarged display data of the fifth packet.
7, the third packet display data 158, the fourth packet display data 159, and the fifth packet display data 160 are enlarged data. 165 is the second packet storage data, 1
66 is the third packet storage data, 167 is the fourth packet storage data, 168 is the fifth packet storage data,
Each of the second packet enlarged display data 161, the third packet enlarged display data 162, and the fourth packet enlarged display data 1
63 and the fifth packet enlarged display data 164 are stored in the first line retrace period 152 corresponding to the idle time of the read operation.
Assigned to the second line retrace period 154. In this embodiment, the read operation is prioritized, and the write operation is performed during the idle time, that is, during the retrace period.

FIG. 16 is an explanatory diagram showing a series of enlargement operations in a screen image.

In FIG. 16, reference numeral 169 denotes an original full screen, 170 denotes an original window screen, and 171 denotes a window display size. The host side displays the original window screen 170 on the original screen 169 and the position of the window display size 171 and You are trying to display in size. 172 is a window transfer screen; 173 is an enlarged window screen;
Are the reception screen of the enlargement control unit 32, the enlargement window screen 1
Reference numeral 73 denotes an output screen of the enlargement control unit 32. 174 is a storage full screen, 175 is a storage window screen, and the storage full screen 174 is the same as the original full screen 169, the full screen on the screen storage means 14, the storage window screen 175.
Is an enlarged window screen 173 written on the screen storage means 14. Reference numeral 176 denotes a full-screen liquid crystal display, which sequentially reads out and displays the entire storage screen 174 on the screen storage means 14 together with the storage window screen 175.

The transfer error processing according to the present embodiment will be described below with reference to FIGS.

First, the flow of data processing will be described with reference to FIGS.

In FIG. 1, the display control unit 8 determines whether the display data 4 is a raster scan method of the conventional mode from the display data mode included in the communication data 6 transmitted in synchronization with the communication clock 7 or not. The upper part is divided by a certain area, and it is determined whether the mode is the packet mode in which only the area in which the display data is desired to be updated is transferred, the display data processing is performed according to the mode, and the stored display data 13 is stored in the screen storage means 14. . Further, in accordance with the display timing of the liquid crystal panel 20, the display data for one screen is read from the screen storage means, and the data line driving signal 9 and the scanning line driving signal 10 are output. The screen storage means 14 has a capacity of at least one screen of the liquid crystal panel 20 and generally has a capacity of S
DRM (Synchronous Dynamic Random Access Memor
A memory means called y) is used.

Referring to FIG. 2, an outline of the operation of display control unit 8 shown in FIG. 1 will be described.

In FIG. 2, the communication control unit 21 determines the necessary values for the input control unit 25 and the enlargement control unit 32 based on the communication data 6 from the host and the control parameters transferred from the host device 100 via the communication clock 7. , Display data is transferred as raster scan data in the conventional mode,
From the data transfer parameter indicating whether only the data of the part whose display is to be updated is transferred by the packet data in the packet mode and the control parameter stored in advance, the enlargement ratio parameter required by the enlargement control unit 25 can be determined in advance. The parameter address 23 and the parameter address 23 are added, and the data is output as parameter data 22 in synchronization with the parameter write strobe 24.

The input control unit 25 stores the parameter address 2
When 3 is an address indicating the data transfer mode information, the parameter data 22, that is, the parameter of the data transfer mode, is taken in according to the timing of the parameter write strobe 24, and is output as the data transfer mode signal 28. When the data transfer mode is the conventional mode and the parameter address 23 is an address indicating the enlargement ratio, the input control unit 25 fetches the parameter data 22, that is, the parameter of the data enlargement ratio, according to the timing of the parameter write strobe 24, The data is output as the data enlargement ratio 29. Next, when the data transfer mode is the packet mode, the packetized display data 4 is separated into parameters and display data, and the data enlargement ratio 29 and the data display position 30 which are packetized in the present embodiment are separated.
And outputs a post-error data valid signal 26 and post-error display data 27 by detecting a transfer error and determining whether or not to perform data processing at a later stage. Also, information on the occurrence of an error is output to the communication control unit 21 as an error information output control signal 31. From the error information output control signal 31 when an error occurs, the communication control unit 21 sends the host device 10 via the communication data 6 to retransmit the packet in which the error has occurred.
Request to the 0 side. When the data transfer mode is the conventional mode, the data valid signal 3 and the display data 4 are output as the data valid signal after error processing 26 and the display data 27 after error processing without performing the separation processing and the error detection processing. The above error processing and retransmission request are repeated until no error is detected.

Referring to FIGS. 3 and 4, display data 4 when display data transfer mode is the packet mode will be described.

In FIG. 3, the data valid signal 3 indicates that the display data 4 is "1" during a valid period. In the conventional mode, only the display data is input when the data valid signal 3 is "1", whereas in the packet mode, the display data is transferred and the display data is enlarged or displayed. In some cases, display control parameters such as a position are transferred. In the first packet data 39, display control parameters are transferred before the window display data is transferred, and then the second packet data 40 and the third packet data 41 are transferred. In each packet, the data in the window area is transferred for each 16 × 16 dot area. In each of the periods in which the window display data valid signal 3 is "1", a head signal 42 and an end signal 44 are added to the main signal 43 which is display data or a display control parameter. The leading signal 42 is
Start information 45 indicating that this is the first packet when the window area whose display is to be updated is divided into a plurality of packets and transferred, and the ID of the window to which the display data 4 belongs
, A main signal type 47 indicating whether the main signal 43 transferred next to the head signal 42 is display data or a display control parameter, and a main signal type 47 indicating that the main signal 43 is display data. It includes a main signal address 48 indicating a display position, and error check information 49 for comparing whether the data on the receiving side of the head signal 42 has not changed from the transmitted data, that is, whether a transfer error has occurred. The end signal 44 is error check information for detecting an error of the signal 43. This signal 43 is
In the case of display data, it is window display data 54 of 8 bits each for RGB of an area consisting of 16 × 16 dots, and in the case of display control parameters, the window horizontal start position 50 which is the horizontal start position address of the window area. A window vertical start position 51 which is a vertical start position address, and
The host side is configured with a window enlargement ratio 52 which is an enlargement ratio at which the window area is to be enlarged.

In FIG. 4, the area on the entire screen 55 where the host device 100 wants to update the display data is the window area 56, and the upper left end of the area is the horizontal window start position 50 and the vertical window shown in FIG. At the start position 51, the window magnification 52
At the same time, in a packet before display data is transferred, the packet is transferred as parameter data before the display data. The display data in the window area 56 is 16 × 16
The packet area 58 in dot units is transferred as one packet, the position at the upper left corner of the first packet area is transferred as the packet area start position 59, and the upper left corner of each packet area is the main signal address 48 shown in FIG. Hit. FIG. 4 illustrates one window area 56, but if this area increases, the top signal 42
Can be dealt with by increasing and identifying the types of data IDs 46 included in. In the present embodiment, two types of data IDs 46, that is,
In the following description, it is assumed that two 6 are handled, but this is for the purpose of explanation only, and the present invention does not limit the number of window areas to be handled. In addition, parameters other than the window display data 54 may be the same for every 8 bits of RGB, and error detection may be performed such that an error occurs when the parameters are different from each other.
It is also possible to shorten the length of the packet. further,
Although the packet area is a rectangular area of 16 × 16 dots, the present invention does not limit the size of the area, and may be a line transfer such as raster scanning in the window area.

With reference to FIGS. 5 to 12, the details of the operation related to the error processing of the input control unit 25 shown in FIG. 2 will be described.

First, the flow of error processing will be described with reference to FIG.

In FIG. 5, the parameter storage unit 60 stores
When the parameter address 23 is an address indicating the data transfer mode, the parameter data 22 is fetched at the timing of the parameter write strobe 24, and is set to "0" when the data transfer mode is the conventional mode and "1" when the data transfer mode is the packet mode. Generated and the data transfer mode signal 28
Output as When the data transfer mode is the conventional mode, and the parameter address 23 is an address indicating the enlargement ratio and the data display position of the conventional mode, the parameter data 22 is fetched at the timing of the parameter write strobe 24, The data is output as the data enlargement ratio 60 and the conventional mode data display position 61. In the case of the packet mode, since the information of the enlargement ratio and the data display position are packetized in the display data 4,
The parameter separating means 63 separates the parameter portion from the display data 4 and outputs a packet mode data enlargement ratio 64,
It is output as the packet mode data display position 65. The data enlargement ratio selector 66 outputs the data transfer mode signal 28
Is "0", that is, in the conventional mode, the conventional mode data enlargement ratio 61 is output as the data enlargement ratio 29. When the data transfer mode signal 28 is "1", that is, in the packet mode, the packet mode is The data enlargement ratio 64 is output as the data enlargement ratio 29. The data display position selector 67 sets the data transfer mode signal 28 to “
When it is "0", that is, in the conventional mode, the conventional mode data display position 62 is output as the data display position 30, and when the data transfer mode signal 28 is "1", that is, in the packet mode, the packet mode data display position is displayed. The position 65 is output as the data display position 30.

When the data transfer mode signal 28 is "1", the packet counting control section 68 controls the packet counting section 72 for determining the order of the transferred packet in which the error has occurred. That is, only when the data transfer mode is the packet mode, the start signal 69, the data ID information 70, and the packet counting clock 71 are generated from the data valid signal 3, the display data 4, and the synchronous clock 5. The packet counting unit 72 resets the start signal 69, counts the number of packets separately for each ID indicated by the data ID 70 using the packet counting clock 71 as a clock, and outputs the result as a packet count value 73.

When the data transfer mode signal 28 is "1", that is, in the packet mode, the error information generating section 74 detects whether or not a transfer error has occurred in the display data 4, and if so, an error has occurred. The signal 77 is used as the signal 77, and information on the place where the error occurs is indicated by the error occurrence state information 7
Output as 6. In addition, a data output control signal 75 for controlling whether to process data is output from the error information generation unit 74 and thereafter. Details will be described later.

The error information storage means 78 stores the data ID information 70, the packet count value and the error occurrence state information 76 according to the error occurrence signal 77, that is, when an error occurs.

The error information output control means 80 waits for the end of the data valid signal 3 and outputs the error information output control signal 81
Is output from the error information storage unit 78, and the storage error information 79, which is the error information generated in the packet, is taken in and output as the error information output control signal 31.
In the present embodiment, the output timing of the error information output control signal 31 based on the error information output control signal 81 is the end point of the data valid signal 3, but the present invention is not limited to this timing.

When the data transfer mode signal 28 is "0", that is, in the conventional mode, the data output control section 82 converts the data valid signal 3 and the display data 4 into the data valid signal after error processing 26 and the display data after error processing. 27
When the data transfer mode signal 28 is "1", that is, in the packet mode, according to the data output control signal 75 which is controlled when an error occurs,
The post-error processing data valid signal 26 and the post-error processing display data 27 are controlled.

With reference to FIGS. 6 to 8, the details of the operation of the packet counting control unit 68 and the packet counting unit 72 shown in FIG. 5 regarding counting the number of packets will be described.

First, the operation of the packet counting control unit 68 shown in FIG. 5 will be described in detail with reference to FIGS.

In FIG. 6, start information decoder 83
Decodes the start information packetized in the display data 4 and outputs “1” as the start information decode signal 84 when indicating the start information. The start information position determining means 85 determines a position where the start information is packetized from the data valid signal 3, and outputs a start information position signal 86. The start signal generation means 87 generates a start signal 69 indicating the start of packet transfer in a certain window area from the start information decode signal 84 and the start information position signal 86.

In FIG. 8, the start information decode signal 84 is “1” in the first packet start information 101 which is the first packet of the data ID 1 and the fourth packet start information 110 which is the first packet of the data ID 2.
It is shown that it becomes. Here, although not shown in FIG. 8, when the main signal portion is display data, it is possible that the value of the start information coincides with the value of the display data.
This shows that the correct start signal 69 is obtained by adding the start information position signal 86 which becomes "1" at the position of the start information of each packet to the condition.

In FIG. 6, data ID discriminating means 88
Determines the position where the data ID is packetized in the packet from the data valid signal 3 in order to capture the information of the data ID packetized in the display data 4.
Output as data ID position signal 89. The data ID generating means 90 takes in only the information part of the data ID packetized in the display data 4 according to the data ID position signal 89 and outputs it as data ID information 70.
In FIG. 8, the data ID position signal 89 indicates that the data ID of each packet is "1" at the position where the data ID is packetized, and that the display data 4 captured at that timing becomes the data ID information 70. I have.

In FIG. 6, the packet counting clock generating means 91 counts the number of packets.
The timing of the data valid signal 3 is reset by the start signal 69 and adjusted so that the count for each data ID can be performed by the data ID information 70, and output as the packet count clock 71. In FIG. 8, the packet counting clock 7
1 indicates that the data valid signal 3 is generated by adjusting the timing.

Next, the operation of the packet counting section 72 shown in FIG. 5 will be described in detail with reference to FIGS.

In FIG. 7, data ID1 decoder 92
Is a data ID1 decode signal 93 which becomes "1" when the data ID information 70 indicates that the data ID is 1.
Is output. Data ID1 packet counting means 94 resets start signal 69, counts enable data ID1 decode signal 93, and packet count clock 71
Performs a counter operation by using as a clock, and outputs a data ID 1 packet count value 95. The operation of the data ID2 decoder 9 and the data ID2 packet counting means 98 is the same. The packet count selector 100 selects the data ID1
When the decode signal 93 is “1” and the data ID2 decode signal 97 is “0”, the data ID1 packet count value 95 is output. The data ID1 decode signal 9
3 is "0" and the data ID2 decode signal 97 is "0".
At the time of “1”, the data ID 2 packet count value 99 is selected and output as the packet count value 73.

In FIG. 8, the data ID1 decode signal 93 becomes “1” in the first to third and fifth packets whose data ID is 1, and the data ID2 decode signal 9
7 indicates that it becomes “1” in the fourth and sixth packets whose data ID is 2. Also, data ID1
The packet count value 95 is the data ID1 decode signal 93
Is counted up in accordance with the packet counting clock 71 only when the data ID is “1”.
Indicates that counting up is performed according to the packet counting clock 71 only when the data ID2 decode signal 97 is “1”. Then, the packet count value 70
Means that the data ID1 decode signal 93 is "1" and the data I
When the D2 decode signal 97 is "0", a data ID1 packet count value 95 is output, the data ID1 decode signal 93 is "0", and the data ID2 decode signal 97 is "1".
Indicates that the data ID 2 packet count value 99 is output.

The means shown in FIGS. 6 and 7 all operate in the packet mode, and the operation is controlled by the data transfer mode signal 28.

In this embodiment, two types of data IDs are described. However, the number of data IDs to be handled can be increased by increasing the number of decoders and counting means shown in FIG. Conversely, when a data ID is not required as in the case of so-called differential transfer in which packet data of only the display update area is simply transferred, the data I shown in FIG.
The D position determining means 88, the data ID generating means 90, and the entire packet counting section 72 shown in FIG. 7 can be omitted. Therefore, the present invention does not limit the presence or absence and the number of data IDs. The present invention is not limited to the configuration examples shown in FIGS. 6 and 7 as long as the means performs the operation shown in FIG.

With reference to FIGS. 9 to 12, the details of the operation of the error information generation unit 74, the error information output control means 80, and the data output control unit 82 shown in FIG. 5 regarding data processing when an error occurs will be described. .

First, the operation of the error information generator 74 shown in FIG. 5 will be described in detail with reference to FIG.

In FIG. 9, the error check information separating means 119 separates the error check information packetized in the display data 4 and outputs it as error check information 120. The error detection unit 121 determines that the display data 4
From the error check information 120, it is determined whether or not the received data matches the data transmitted by the host side.
Is output. The error check information 120 and the error detection means 121 depend on an error detection method, and the present invention does not particularly limit the detection method.
General parity check, CRC (Cyclic Redundanc)
y Code) can be used. The data counting unit 122 counts the number of data in the packet using the data valid signal 3 and the synchronous clock 5 to determine the position where the error has occurred, and outputs a data count value 123. The error state determination means 124 determines the position where the error has occurred from the error occurrence signal 77 and the data count value 123, and determines whether the error is in the head signal portion.
It is output as error occurrence state information 76 indicating whether the error is in the parameter portion or the display data portion. The data output control signal generation means 75 controls the data output control signal generation means 75 to stop the data output to the following means in the case of the error of the head signal and in the case of the parameter error, The data output control signal 75 is generated so as not to stop the output.

Next, the operation of the data output control unit 82 shown in FIG. 5 will be described in detail with reference to FIG.

In FIG. 10, packet output control means 1
Reference numeral 26 denotes a packet output control signal 127 for adjusting timing for outputting packet data after error detection and stopping the data output according to the data output control signal 75 when a head signal error and a parameter error occur.
Generate The packet storage unit 128 temporarily stores the data valid signal 3 and the display data 4 for one packet in order to adjust the data output timing, and stores the data valid signal 129 for the storage unit according to the packet output control signal.
And the storage means output display data 130 is output. The data valid signal selector 131 outputs the data transfer mode signal 2
When 8 is "0", that is, in the conventional mode, the data valid signal 3 is selected, and the data transfer mode signal 28 is set to "1".
, Ie, in the packet mode, the storage means output data valid signal 129 is selected and output as the data valid signal 26 after error processing. Display data selector 132
Selects the display data 4 when the data transfer mode signal 28 is "0", that is, the conventional mode, and selects the storage means output display data 130 when the data transfer mode signal 28 is "1", that is, the packet mode. Select and output as display data 27 after error processing.

With reference to FIGS. 11 and 12, the details of the above operation will be described for each type of error that occurs.

FIG. 11 shows a case where an error has occurred in the third packet head signal 137, fourth packet main signal 140, and sixth packet head signal 143 shown in gray. If no error occurs, the data output control signal 75 is set to "1". When an error occurs in the first signal, the packet data cannot be displayed. Therefore, the data output control signal 75 is set to “0” so as not to output the packet data in which the error has occurred. Also,
In the case of a display data error, since there is no error in the data of the first signal, the data output control signal 75 is set to "1" without stopping the data output. When an error occurs, a retransmission request is made, and after that, packet data retransmitted from the host device 100 can be received, and correct packet data can be obtained.

FIG. 12 shows that an error has occurred in the parameters of the first main packet signal 134 shown in gray. For the parameter error indicating the enlargement ratio or display position of one packet, the same data ID after that
Since the display data of the packet having the same data ID is not correctly displayed, all the packet data having the same data ID transferred thereafter are affected. In this case, it is impossible to display correctly regardless of the data error of the second and subsequent packets. Therefore, the data output control signal 75 is set to "0" so as to stop all data output of the subsequent packets. Is shown. Therefore, the subsequent processing is not performed for all packets having the same data ID as the data in which the error has occurred.
Perform processing when resent.

FIG. 18 shows a data format diagram of an error message notified to the host device 100 when an error occurs. In FIG. 18, error message 5
00 is a retransmission request command 510 indicating a retransmission request, a data ID 520 indicating a data ID in which an error has occurred,
A packet number 530 and an error position 540 indicating an error occurrence position are provided. The error message 500 is shown in FIG.
2 is generated in the communication control unit 21 shown in FIG. 2 in accordance with the error information output control signal 31 transmitted from the error information output control unit 80 of the input control unit 25 shown in FIG. . The error position 540 indicates whether there is a head signal error, a parameter error, or a display data error.

In the host device 100 shown in FIG. 17, upon receiving the error message 500, the corresponding packet is retransmitted. In the case of a parameter error, all packets identical to the data ID in which the error has occurred are retransmitted. In the case of a head signal error or display data error, the packet data of the packet number of the data ID in which the error has occurred is retransmitted.

The above operation is repeated until no error occurs for the retransmitted packet data, thereby completing the data transfer of the display update area.

Next, with reference to FIGS. 2 and 13 to 16, data processing after error processing of the enlargement control unit 32 shown in FIG. 2 will be described.

First, the data flow will be described with reference to FIG.

In FIG. 2, the enlargement control section 32 controls the vertical synchronizing signal 1, the horizontal synchronizing signal 2, the data valid signal after error processing 26, and the display data 27 after error processing in accordance with the data transfer mode signal 28 and the data expansion rate 29. Then, the enlarged display data address 34 and the enlarged display data 33 are generated from the synchronous clock 5. The output timing follows the storage timing signal 36.

The storage control section 35 outputs a storage / read command 11 for reading data from the screen storage means 14 as a read command in accordance with the display timing of the liquid crystal panel 20, and also outputs a storage / read address 12. The read screen read data 15 is output as liquid crystal panel display data 37. The storage timing signal 36 is output so that the enlarged display data is written to the screen storage unit 14 at a time other than the read timing. This is generated as a command, and the storage read address 12 and the storage data 13 are generated together. The liquid crystal display signal generation unit 38 outputs the liquid crystal panel display data 37
Then, a data line driving signal 9 and a scanning line driving signal 10 are generated.

With reference to FIGS. 13 and 14, details of the packet data enlargement processing operation in enlargement processing section 32 will be described.

In FIG. 13, the main signal separation section 145 extracts the main signal 43 shown in FIG. 3 from the start position of the data valid signal 3, and as shown in FIG. A packet mode display valid signal 146 is generated, and only this signal 43 is used as packet mode display data 147, and the packet mode display data synchronous clock 1
Output in synchronization with 48. Therefore, as shown in FIG. 14, the packet mode display data valid signal 146
Only a portion of the window data 54 of the packet data 40 and the third packet data 41 becomes "1". The data enlargement unit 149 controls the data transfer mode signal 28
Is "0" indicating the conventional mode, the data expansion rate 2
9, a vertical synchronizing signal 1, a horizontal synchronizing signal 2, and an error-processed data valid signal 2
6. Display data 27 after error processing and synchronous clock 5
, The enlarged display data 33 is generated. When the packet mode is "1", the enlargement process according to the data enlargement ratio 29 is performed, and the packet mode display data valid signal 14
6. The enlarged display data 33 is generated from the packet mode display data 147 and the packet mode display data synchronization clock 148. When the data transfer mode signal 28 is “0” indicating the conventional mode, the address processing unit 150 stores all the data for one screen in the screen storage unit 14 from the beginning. An enlarged display data address 34 is generated from the signal 2 and the post-error data valid signal 26, and when “1” indicating the packet mode, only the display data of the area transferred to the screen storage unit 14 is stored. The enlargement of the address at the data display position 30 by the data enlargement ratio 29 is calculated, and an enlarged display data address 34 is generated.

With reference to FIG. 15, the timing of the above enlargement processing will be described.

In FIG. 15, screen read data 15
Indicates the first line read data 151, line by line in accordance with the raster scan timing of the liquid crystal panel 20.
First line retrace period 152, second line read data 1
53 and the second line read data 154 are read in accordance with a certain cycle. The display data 4 is
Following the first packet data 39, the second packet data 40, and the third packet data 41 shown in FIG.
Packet data 155 and fifth packet data 156
Is input. For these first to fifth packet data, the packet mode display data 140 is
Since only the window display data 54 shown in FIG. 3 is valid, nothing is transferred from the first packet data 39 to which the display control parameter is transferred, and the window display data portion in the second to fifth packet data is not transferred. The second packet display data 157 and the third packet display data 15
8. The fourth packet display data 159 and the fifth packet display data 160 are transferred. The enlarged display data 33 is
In order to enlarge the second to fifth packet display data in accordance with the data enlargement ratio transferred in the first packet data, the second packet enlarged display data 161, the third packet enlarged display data 162, and the fourth packet enlarged display data 7
As shown in 163 and the fifth packet enlarged display data 164, the data period is longer. Since the display on the liquid crystal panel 20 is performed by the raster scan method, the stored display data 13 is read out preferentially, and the first line retrace period 152 and the second line retrace period which are the retrace periods thereof are performed. In 154, the second packet storage data 165, the third packet storage data 166, the fourth
This shows that the packet storage data 167 and the fifth packet storage data 168 are transferred.

Therefore, the storage control unit 35 shown in FIG.
It is desirable to have storage means for several lines.
Side, the data transfer may be performed in accordance with the read retrace period. If the data transfer from the host device 100 collides with the read period, retransmission is performed by returning an error signal. You may request.

Referring to FIG. 16, the enlarging process will be described with a screen image.

In FIG. 16, the conventional mode is a raster scan method in which display data of the entire original screen 169 is transferred at a fixed cycle for each line. As 170, only the display data in this area is further subdivided into a 16 × 16 dot area, and transferred in a format to which a display control parameter is added. At this time, the host adds an enlargement factor for enlarging the original window screen 170 to the window display size 171. Therefore, the window transfer screen 172 has the original size, and becomes the enlarged window screen 84 by the enlargement processing. The entire storage screen 174 needs to be written at the time of initial startup, but only the updated portion is written thereafter.
It is shown that only 73 is written as the storage window screen 175. The liquid crystal panel display indicates that the entire storage screen 174 is read out including the storage window screen 175 and the enlarged liquid crystal display full screen 176 is displayed on the screen.

The transfer, error recovery, enlargement, and display of the window area are completed as described above. According to the present embodiment, by judging an error position, processing can be made different in accordance with the error position. In addition, when an error occurs, the packet data is retransmitted, so that packet data without error can be displayed. According to the present embodiment, even if an error occurs during the transfer of packet data from the host device to the display device, the display device can detect the error, request retransmission of the packet data, and accept the retransmitted packet data. As a result, the display data in which an error has occurred is not displayed, and the transfer error does not affect the display.

In the above embodiment, the packet number having the same data ID is counted to determine the packet number. However, if the host apparatus 100 adds the packet number to the packet data, the packet counting unit is not provided. You may. In this case, a packet number detecting unit is provided to detect a packet number in which an error has occurred. Further, in the above embodiment, when a parameter error occurs, a request is made to retransmit all the packet data of the same data ID.
By holding the packet data of D, only the packet data of the parameter portion where the error has occurred may be requested to be retransmitted.

[0113]

According to the present invention, even if an error occurs during the transfer of packet data from the host device to the display device,
When a transfer error occurs, the error can be recovered without being left as a display.

[Brief description of the drawings]

FIG. 1 is a block diagram of a display device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of an internal configuration of a display control unit 8 shown in FIG.

FIG. 3 is an explanatory diagram of packet data according to the first embodiment.

FIG. 4 is an explanatory diagram illustrating an image transfer image based on packet data according to the first embodiment.

FIG. 5 is a block diagram of an internal configuration of an input control unit 25 shown in FIG.

FIG. 6 is a block diagram of an internal configuration of a packet counting control unit 68 shown in FIG.

FIG. 7 is a block diagram of an internal configuration of a packet counting unit 72 shown in FIG.

FIG. 8 is an explanatory diagram showing operations of a packet counting control unit 68 and a packet counting unit 72 shown in FIG.

9 is a block diagram of an internal configuration of an error information generation unit 74 shown in FIG.

FIG. 10 is a block diagram of an internal configuration of a data output control unit 82 shown in FIG.

FIG. 11 is an explanatory diagram showing operations at the time of a head signal error and a display data error in the error information generation unit 74 and the data output control unit 82 shown in FIG.

FIG. 12 is an explanatory diagram showing an operation at the time of a parameter error in the error information generation unit 74 and the data output control unit 82 shown in FIG. 5;

FIG. 13 is a block diagram of an internal configuration of an enlargement control unit 32 shown in FIG.

14 is an explanatory diagram showing an operation of the main signal separation unit 145 shown in FIG.

FIG. 15 is an explanatory diagram showing an operation of the data enlargement processing unit 149 shown in FIG.

FIG. 16 is an explanatory diagram showing a flow of an image from packet transfer to enlarged display according to the present invention.

FIG. 17 shows a host device 100 according to the embodiment of the present invention.
FIG. 3 is a hardware configuration diagram of FIG.

FIG. 18 is a data format diagram when notifying occurrence of an error in the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vertical synchronous signal, 2 ... Horizontal synchronous signal, 3 ... Data valid signal, 4 ... Display data, 5 ... Synchronous clock, 6 ... Communication data, 7 ... Communication clock, 8 ... Display control part, 9 ... Data line drive Signal, 10: scanning line drive signal, 11: storage /
Read command signal, 12... Storage / read address, 1
3 ... stored data, 14 ... screen storage means, 15 ... screen readout data, 16 ... data line drive means, 17 ... data line drive signal, 18 ... scan line drive means, 19 ... scan line drive signal, 20 ... liquid crystal panel, Reference numeral 21: communication control unit, 22: parameter data 22, parameter address, 24: parameter write strobe, 25: input control unit, 26: data valid signal after error processing, 27: display data after error processing, 28: data transfer mode signal , 29: data enlargement ratio, 30: data display position, 31: error information, 32
... Enlargement control unit, 33 ... Enlarged display data, 34 ... Enlarged display data address, 35 ... Storage control unit, 36 ... Storage timing signal, 37 ... Liquid crystal panel display data, 38 ... Liquid crystal display signal generation unit, 39 ... First packet , 40: second packet, 41: third packet, 42: head signal, 43: main signal, 44: end signal, 45: packet start information,
6 ... Data ID, 47 ... This signal type, 48 ... This signal address, 49 ... Head signal error check information, 50 ... Window horizontal start position, 51 ... Window vertical start position, 52 ... Window enlargement ratio, 53 ... Number Signal error check bit, 54 ... window display data, 55 ... whole screen, 56 ... window area, 57 ... window area start position, 58 ... packet area, 59
... Packet area start position, 60 ... Parameter storage unit, 61 ... Conventional mode data enlargement ratio, 62 ... Conventional mode data display position, 63 ... Parameter separation means, 64 ... Packet mode data enlargement ratio, 65 ... Packet mode data display position 66: data enlargement ratio selector, 67: data display position selector, 68: packet count control unit, 69
... Start signal, 70 ... Data ID information, 71 ... Packet count clock, 72 ... Packet count section, 73 ... Packet count value, 74 ... Error information generation section, 75 ... Data output control signal, 76 ... Error occurrence state information, 77 ... Error occurrence signal, 78 ... Error information storage means, 79 ... Storage error information, 80 ... Error information output control means, 81 ... Error information output control signal, 82 ... Data output control unit, 83 ... Start information decoder, 84 ... Start Information decode signal,
85 ... start information position determination means, 86 ... start information position signal, 87 ... start signal generation means, 88 ... data ID position determination means, 89 ... data ID position signal, 90 ...
Data ID generating means, 91: Packet counting clock generating means, 92: Data ID1 decoder, 93: Data ID
1 decode signal, 94 data ID1 packet counting means, 95 data ID1 packet count value, 96 data ID2 decoder, 97 data ID2 decode signal, 9
8 ... Data ID2 packet counting means, 99 ... Data ID
2 packet count value, 100... Packet count value selector,
101: first packet start information, 102: first packet data ID, 103: first packet main signal, 104
... second packet start information, 105 ... second packet data ID, 106 ... second packet main signal, 107 ... third
Packet start information, 108... Third packet data I
D, 109: third packet main signal, 110: fourth packet start information, 111: fourth packet data ID, 1
12: fourth packet main signal, 113: fifth packet start information, 114: fifth packet data ID, 115 ...
Fifth packet main signal, 116 ... sixth packet start information, 117 ... sixth packet data ID, 118 ... sixth packet main signal, 119 ... error check information separation means,
120 error check information, 121 error detection means, 122 data counting means, 123 data count value,
124: error state determination means, 125: data output control signal generation means, 126: packet output control means, 127
... a packet output control signal, 128 ... packet storage means,
129: storage means output data valid signal, 130: storage means output display data, 131: data valid signal selector,
132 ... display data selector, 133 ... first packet head signal, 134 ... first packet main signal, 135 ... second
Packet head signal, 136... Second packet main signal, 13
7: third packet head signal, 138: third packet main signal, 139: fourth packet head signal, 140: fourth packet main signal, 141: fifth packet head signal, 142 ...
Fifth packet main signal, 143 ... sixth packet head signal,
144 ... sixth packet main signal, 145 ... main signal separation unit,
146: packet mode display valid signal, 147: packet mode display data, 148 ... packet mode synchronous clock, 149 ... data enlargement processing unit, 150 ... address processing unit, 151 ... first line read data, 152 ... first
Line retrace period, 153... Second line read data,
154: second line flyback period, 155: fourth packet data, 156: fifth packet data, 157: second packet display data, 158: third packet display data, 1
59: fourth packet display data, 160: fifth packet display data, 161: second packet enlarged display data, 1
62: third packet enlarged display data, 163: fourth packet enlarged display data, 164: fifth packet enlarged display data, 165 ... second packet storage data, 166 ... third
Packet storage data, 167: fourth packet storage data, 168: fifth packet storage data, 169: original full screen, 170: original window screen, 17
1 ... window display size, 172 ... window transfer screen, 173 ... enlarged window screen, 174 ... storage full screen, 175 ... storage window screen, 176 ... liquid crystal display full screen.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshio Futami 3300 Hayano, Mobara-shi, Chiba Prefecture Hitachi Display Group (72) Inventor Tomoyuki 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Hitachi, Ltd. F term in the information system (reference) 5B069 AA01 AA02 BA04 BB16 KA05 LA02 NA03 NA05 5C080 AA10 BB05 DD09 DD14 EE21 EE32 FF09 JJ01 JJ02 JJ04 KK02

Claims (5)

[Claims] A display control unit configured to perform display control in accordance with packet data including display data from a host device; and a display unit for displaying an image. Error detecting means for receiving packet data to which error check information for checking the error has been added, and performing error detection based on the error check information; and when the error detecting means detects an error, An output device for outputting a packet data retransmission request. 2. A display control unit comprising: a display control unit for performing display control in accordance with packet data including display data from a host device; and a display unit for displaying an image. Error detection means for receiving packet data to which error check information for checking the packet data is added for each predetermined area of the packet data, and performing error detection for each area based on the error check information; Output means for outputting a request for retransmission of the packet data to the host device when an error is detected by the means, wherein the display control means performs predetermined error processing for each area where the error has occurred. A display device characterized by performing. 3. The display device according to claim 2, wherein said output means, when outputting said retransmission request, outputs information indicating an area in which said error has occurred. 4. An information processing apparatus for transmitting packet data including display data to a display device, wherein the transmitting device adds error check information for checking an error to the packet data and transmits the packet data. Receiving means for receiving a retransmission request for packet data in which an error has occurred, and control means for controlling the packet data to be retransmitted by the transmitting means when the receiving means receives the retransmission request. Information processing device. 5. The information processing apparatus according to claim 4, wherein
The information processing apparatus according to claim 1, wherein the transmission unit adds the error check information to each predetermined area of the packet data and transmits the packet data.