JP2005345779A - Lcd control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain the reduction of a system having an LCD and the curtailment of a cost by enabling the curtailment of terminals for LCD control in the system. <P>SOLUTION: A host system 11 forms transfer data by multiplexing the pixel data included in an image data output block 20 and LCD control data 19 generated by a control block 12 by an LCD control data multiplex block 22 which is a multiplexing means. An LCD controller unit 12 separates and fetches the pixel data and LCD control data multiplexed from the transfer data by an LCD interface block 23. At the time of multiplexing of the pixel data and the LCD control data, the pixel data is formed as the transfer data in an effective section of a vertical synchronizing signal signal 13 or horizontal synchronizing signal 14 and the LCD control data is formed as the transfer data in an invalid section of the vertical synchronizing signal signal 13 or the horizontal synchronizing signal 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for configuring a system having a liquid crystal display (LCD), and more particularly, to a control technique for transferring data from a host device to an LCD control device.

  Conventionally, there is a method described in Patent Document 1 as a register setting method for an LCD control device or the like. FIG. 6 is a block diagram showing a configuration example of a conventional LCD control system. In FIG. 6, in order to control the LCD control device 12 from the host device 11, the image data transfer terminal group 47 and the LCD control data transfer terminal group 48 are connected to each other.

  In general, the image data transfer terminal group 47 includes a vertical synchronization signal 13, a horizontal synchronization signal 14, a pixel clock 15, an R pixel transfer line 16, a G pixel transfer line 17, and a B pixel transfer line 18. The LCD control data transfer terminal group 48 includes an address 44, data 45, and a control signal 46.

The host device 11 has an image data output block 20 for transferring image data to the image data transfer terminal group 47 and a control block 21 for transferring LCD control data to the LCD control data transfer terminal group 48. The LCD control device 12 has an LCD interface block 23 that serves as an interface between the image data transfer terminal group 47 and the LCD control data transfer terminal group 48.
JP-A-6-103210

  In the conventional system configuration described above, it is necessary to provide a serial port or the like for register setting of the LCD control device, like the LCD control data transfer terminal group. For this reason, there is a problem that the chip size of the LCD control LSI is increased and the wiring on the substrate is increased.

  According to the present invention, in a system having an LCD, the system scale can be reduced by making it possible to share a pixel data input port without providing a serial port or the like for register setting of the LCD controller. An object is to provide an LCD control system.

  The LCD control system of the present invention is an LCD control system for transferring LCD control data, pixel data, a vertical synchronization signal, and a horizontal synchronization signal from a host device to the LCD control device. The LCD control device includes multiplexing means for multiplexing the LCD control data to obtain transfer data, and the LCD control device includes means for separating the multiplexed pixel data and the LCD control data from the transfer data.

  According to the above configuration, since pixel data and LCD control data are multiplexed and transferred from the host device to the LCD control device, the existing data port can also be used for register setting of the LCD control device. By eliminating the need for a serial port, the system can be reduced in size and cost.

  In the present invention, the multiplexing of the pixel data and the LCD control data is performed by using the pixel data as transfer data in an effective section of the vertical synchronization signal or the horizontal synchronization signal, and invalidating the vertical synchronization signal or the horizontal synchronization signal. In the section, the LCD control data is used as transfer data.

  According to the above configuration, the LCD control data is transferred during the invalid period of the vertical synchronization signal or the horizontal synchronization signal, so that the pixel data and the LCD control data can be multiplexed without reducing the conventional pixel data transfer speed. it can.

  In the present invention, the LCD control data is a data string that starts with a control data transmission start code and ends with a control data transmission end code.

  According to the above configuration, since the LCD control data is delimited by the control data transmission start code and the control data transmission end code, the invalid pixel data and the LCD control data can be clearly distinguished, and the system reliability can be improved. Can be planned.

  In the present invention, the LCD control data includes a data string in which an address and an LCD command are paired, or a data string including an LCD command continuous with one address.

  According to the above configuration, since a data string consisting of LCD commands that are continuous with one address can be used as LCD control data, a large number of registers can be set in a shorter time in register setting of the LCD control device.

  In the present invention, the host device stores the pixel data and the LCD control data separately in memory areas each given a base address.

  According to the above configuration, since the transfer data can be controlled only by changing the base address in the host device, the configuration of the control circuit can be simplified.

  According to the present invention, pixel data and LCD control data are multiplexed and transferred from the host device to the LCD control device, thereby reducing the serial port for transmitting control data to the LCD control device as compared with the conventional case. Therefore, the system can be reduced in size and cost.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an LCD control system according to an embodiment of the present invention. In FIG. 1, a system having an LCD includes a vertical synchronization signal 13, a horizontal synchronization signal 14, a pixel clock 15, an R pixel transfer line 16, a G pixel transfer line 17, and a B pixel between the host device 11 and the LCD control device 12. The transfer line 18 is connected by an image related signal.

  In the host device 11, an image data output block 20 that outputs image-related signals 13 to 18, a control block 21 that generates LCD control data 19, and the LCD control data 19 are converted into pixel data of the pixel transfer lines 16 to 18. The LCD control data multiplexing block 22 to be multiplexed is provided.

  Further, the LCD control device 12 includes an LCD interface block 23 for separating the pixel data multiplexed on the pixel transfer lines 16 to 18 and the LCD control data 19. FIG. 2 is a block diagram showing a configuration example of the LCD interface block 23.

  In FIG. 2, the pixel transfer lines 16 to 18 are input to the data separation block 24, and the data input in the valid section of the vertical synchronization signal 13 and the horizontal synchronization signal 14 is sent to the LCD driver block 25 as pixel data 28.

  On the other hand, the data input in the invalid period of the vertical synchronizing signal 13 and the horizontal synchronizing signal 14 is sent to the control data decoding block 26 as the LCD control data 19. The LCD control data 19 is decoded into an address, data, and a control signal by the control data decoding block 26, and the register group 27 designated by these is accessed.

  FIG. 3 is a timing chart showing an example of a method for multiplexing pixel data and LCD control data. In FIG. 3, the vertical synchronization signal 13 usually has a pixel invalid data section 30. In this pixel invalid data section 30, the LCD control data 19 is transferred using the R pixel transfer line 16. Of the invalid data section 30, a section where the LCD control data 19 is not transferred becomes unused invalid data 31.

  FIG. 4 is a diagram illustrating a format example when the LCD control data 19 is transmitted in the pixel data invalid section 30. The LCD control data 19 transfer period is a period from when the control data transmission start code is transferred to when the control data transmission end code is transferred. In the meantime, there are a normal access section 32 for transferring a register address and data in pairs, a continuous access section 33 for continuously transferring data to a continuous address space, and the like.

  FIG. 5 is a diagram showing a method of storing LCD control data and pixel data in the memory space in the present embodiment. The LCD control data is continuously stored in the memory area starting from the LCD control data storage area base address 35, and the pixel data is continuously stored in the memory areas starting from the respective pixel storage area base addresses 36 to 38. Since transfer data can be distinguished only by controlling these base addresses during data transfer, the control circuit for generating addresses can be simplified.

  The LCD control system of the present invention can be diverted to a system that controls an operation target using a data signal and a control signal. Even in that case, since the system scale can be reduced by the addition of simple control as in the system described in the present invention, it is considered that the possibility of being used is high.

The block diagram which shows the structure of the LCD control system which concerns on one embodiment of this invention. The block diagram which shows the structural example of the LCD interface block placed in a LCD control apparatus in the LCD control system of this invention. The timing chart which shows an example of the method of multiplexing the pixel data and LCD control data in the LCD control system of this invention. The figure which shows the example of a format at the time of transmitting LCD control data in a pixel data invalid area at the time of the data multiplexing in the LCD control system of this invention. The figure which shows the storage method in the memory space of the LCD control data and pixel data in the LCD control system of this invention. The block diagram which shows the structural example of the conventional LCD control system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Host apparatus 12 LCD controller 13 Vertical synchronizing signal 14 Horizontal synchronizing signal 15 Pixel clock 16 R pixel transfer line 17 G pixel transfer line 18 B pixel transfer line 19 LCD control data 20 Image data output block 21 Control block 22 LCD control data multiplexing Block 23 LCD interface block 24 Data separation block 25 LCD driver block 26 Control data decode block 27 Register group 28 Pixel data 29 Operation clock 30 Pixel data invalid section 31 Invalid data 32 Normal access section 33 Continuous access section 34 Memory space 35 LCD control data Storage area base address 36 R pixel storage area base address 37 G pixel storage area base address 38 B pixel storage area base address 39 1 pixel Data 40 LCD control data storage area 41 R pixel storage area 42 G pixel storage area 43 B pixel storage area 44 address 45 data 46 control signal 47 image data transfer terminal group 48 LCD control data transfer terminal group

Claims (5)

An LCD control system for transferring LCD control data, pixel data, a vertical synchronization signal, and a horizontal synchronization signal from a host device to an LCD control device,
The host device includes multiplexing means for multiplexing the pixel data and the LCD control data to obtain transfer data,
The LCD control device comprises a means for separating and extracting the multiplexed pixel data and the LCD control data from the transfer data.   In the multiplexing of the pixel data and the LCD control data, the pixel data is used as transfer data in the valid section of the vertical synchronization signal or the horizontal synchronization signal, and the pixel data and the LCD control data are used in the invalid section of the vertical synchronization signal or the horizontal synchronization signal. 2. The LCD control system according to claim 1, wherein the LCD control data is transfer data.   2. The LCD control system according to claim 1, wherein the LCD control data is a data string that starts with a control data transmission start code and ends with a control data transmission end code.   2. The LCD control system according to claim 1, wherein the LCD control data includes a data string in which an address and an LCD command are paired, or a data string including an LCD command continuous with one address.   2. The LCD control system according to claim 1, wherein the host device stores the pixel data and the LCD control data separately in a memory area to which a base address is assigned.

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