JPH02179681A - Controller for dot matrix display medium - Google Patents

Abstract

PURPOSE:To immediately display a moving picture of TV broadcast or the like by writing information corresponding to one frame of a display medium in a RAM in a write cycle and immediately reading out information in the order adapted to the characteristic of the display medium in the next read cycle to drive display elements of the display medium. CONSTITUTION:With respect to an electrostatic display device 13, many display units each of which is provided with two fixed electrodes and a mobile electrode attracted by the electrostatic force of one of these fixed electrodes are arranged in a matrix to constitute one panel. A RAM 9 is provided with the storage capacity larger than the number of constituted display units of the device 13 and has the same number of rows and columns as the matrix of the device 13. A picture signal of one frame is written in two periods of a vertical synchronizing signal in the order according with horizontal-direction interlaced scanning in the same manner as TV scanning at the time of write and is successively read out with a column as the unit in the read cycle. Thus, a moving picture is immediately displayed.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a control device for a dot matrix type display medium, and more specifically, it is used to control the display contents of a large dot matrix type display medium installed outdoors or in an auditorium. It relates to a device to be controlled.

<Prior Art> As one of the conventional large dot matrix type display media, for example, the electrostatic display device described in Japanese Patent Application Laid-Open No. 60-172093 or Japanese Patent Application Laid-Open No. 60-172094 is known. . Additionally, electric display panels, LED display panels, and the like are known.

In order to control the display content of these conventional display media, the display data was stored in advance in an external or internal storage device such as a magnetic disk, and the format and speed of the data were converted via the CPU, so the video signal could be displayed immediately. was impossible.

<Problems to be Solved by the Invention> Video software for CRT includes various types of video software for PCs, in addition to those shot by various television broadcasts and video cameras. An object of the present invention is to provide a control device for a dot matrix type display medium which can be applied to any of these video software and which can display images immediately.

<Means for Solving the Problems> A control device for a dot matrix type display medium of the present invention has the following features:
An input terminal for introducing a horizontal scanning image signal and its synchronization signal, a RAM for storing one screen of data to be displayed by the display medium, and a RAM control means for writing and reading the image signal into and from the RAM. , above R
It is characterized by having a read/write selector section that alternately controls writing and reading of the RAM, and data output means that outputs data read from the RAM to the display medium.

<Function> For both the output signal of a video camera or the CRT signal of television broadcasting, one-screen information in interlaced horizontal scanning is written into the memory as is. Subsequently, the contents stored in the RAM are read out according to the scanning method of the display medium and displayed on the display medium. This alternating control is executed by the read/write selector section. By repeating this reading and writing, the input video information is immediately and continuously displayed.

<Example> FIG. 1 shows a block diagram of an embodiment of the present invention.

The first input terminal 1 is connected to a composite signal (composite video signal) output terminal of a video camera or a television receiver. The composite signal includes a video signal, a horizontal sync signal, and a vertical sync signal.

The second input terminal 2 is a terminal connected to a personal computer, into which display output signals (RGB signals), synchronization signals, and clock signals of the personal computer are introduced.

The synchronization separator 3 separates the horizontal synchronization signal and the vertical synchronization signal from the composite signal, and the A/D converter 4 converts the remaining video signal into a digital video signal.

The internal clock signal generator 5 is an input clock signal generator 5a for controlling writing to the RAM 9, which will be described later.
and an output clock signal generator 5b for controlling reading from the RAM 9. The mode selector unit 6 selects either the synchronization signal of the composite signal input from the first input terminal or the synchronization signal input from the second input terminal according to the control signal, and selects the synchronization signal of the composite signal input from the first input terminal, and
The write selector section 7 creates a read cycle and a write cycle every two cycles of the vertical synchronization signal. The mode selector section 6 also receives this read/write signal, horizontal synchronization signal,
and a clock signal to generate an address counter control signal. The address control section 8 generates an address signal for the RAM 9 according to the read/write signal and the address counter control signal, while in the write cycle,
In conjunction with the state of the mode selector section 6, the data selector section 10 selects either the video signal input from the first or second input terminal, and sends the video signal to the address specified by the address control section 8. In the write and subsequent read cycles, the written video signal is read out in a predetermined scanning method according to the clock signal of the output clock generator 5b. This readout address control is performed in parallel for each row or column (parallel method), converted into serial data by the data converter 1) (serial method), converted into an optical signal by the data transmitter 12, and then It is transmitted to a display medium installed at the location, for example a capacitive display device.

FIG. 2 shows a time chart of the main signals of this embodiment. (a) The figure shows a vertical synchronization signal selected by the mode selector section 6 from among the vertical synchronization signals created by a television broadcast, a video camera, or a personal computer. (b) The figure shows a vertical synchronization signal selected by the mode selector section 6. The read/write signals shown in Figures (C1) and (C2) are enlarged displays of the clock signals in the write cycle and the read cycle at the same magnification. In the write cycle, the signal is generated by an external device such as a personal computer or the input clock generator 5a, and in the read cycle, it is a signal generated by the output clock generator 5b. In this embodiment, the period t2 of the output clock is twice the period t1 of the input clock. Address control is performed based on this clock signal.

The electrostatic display device 13, which serves as a display medium, has a large number of display units arranged in a matrix, each of which has two fixed electrodes and a movable electrode that is attracted to one of the fixed electrodes by electrostatic force. It consists of two display panels, and can perform a wide range of displays such as still image display, continuous display, and moving image display. In this invention,
Displays images from TV broadcasts, TV cameras, computers, etc. in real time. In such display media, matrix format columns (
It is more convenient to use a method that scans each image (vertical direction).

On the other hand, as is well known, scanning of a television or a video camera is commonly performed by interlacing every other line in the horizontal direction.

Therefore, in this embodiment, the RAM 9 is the display medium 1.
3, and has the same number of rows and columns as the matrix format of the display medium 13,
In the write cycle, one frame of image signal is written in two cycles of the vertical synchronization signal in an order that follows horizontal interlaced scanning, similar to the scanning method of television, and in the read cycle, it is sequentially read out column by column. .

Figure 3 shows the write order of write cycles with broken lines.
The read order of the read cycle is shown by a solid line. Note that the read cycle time is not limited to two periods of the vertical synchronization signal, but can also be set to three or four periods.

FIG. 4 shows another embodiment of the invention. This device connects only a personal computer to the input side and is intended to immediately display the CRT output of the personal computer on a display medium. Components that are the same as those in the embodiment shown in FIG. 1 are given the same reference numerals, and their explanations will be omitted.

FIG. 5 shows still another embodiment of the present invention. This device connects only a video camera to the input side and immediately displays the CRT output of the video camera on a display medium. Components that are the same as those in the embodiment shown in FIG. 1 are given the same reference numerals, and their explanations will be omitted.

<Effects of the Invention> According to the present invention, in a write cycle, even an analog video signal is converted into digital data, information corresponding to one frame of the display medium is written to the RAM, and the characteristics of the display medium are converted in the next read cycle. Since the display elements of the display medium can be driven immediately while being read in an order suitable for the
It became possible to instantly display moving images such as T.

Furthermore, by controlling readout from the RAM, it is possible to easily support any type of display medium.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIGS. 2 and 3 are explanatory views of the operation of the embodiment of FIG. FIG. 4 is a block diagram showing another embodiment of the invention, and FIG. 5 is a block diagram showing still another embodiment of the invention.

Claims (2)

[Claims] (1) An input terminal for introducing a horizontal scanning image signal and its synchronization signal, a RAM for storing one screen of data to be displayed on the display medium, and an input terminal for inputting the image signal into the RA.
RAM control means for writing to and reading from M;
A control device for a dot matrix type display medium, comprising a read/write selector section that alternately controls writing and reading of the RAM, and a data output means that outputs data read from the RAM to the display medium. (2) a first input terminal for introducing a composite signal from a video camera, etc.; a second input terminal for introducing a display output signal and a synchronization signal from a personal computer;
an A/D converter that converts a video signal introduced from the input terminal of the device into a digital signal; a RAM that stores one screen of data to be displayed on the display medium; a synchronization signal separated from the composite signal; a mode selector section that selects either the synchronization signal of the computer introduced from the second terminal; and a video signal separated from the composite signal or the display output signal of the computer in conjunction with the mode selector section; a data selector section for selecting a data selector section; a RAM control means for writing and reading output data of the data selector section into and from the RAM in synchronization with the mode selector section; A control device for a dot matrix type display medium, which has a data output means for outputting data.