KR100263401B1 - Display device - Google Patents

Abstract

The present invention aims at performing a natural scroll display.

This display device is composed of a plurality of slave modules 100 connected to the master module 1 in cascade.

The display data input to the master module 1 is converted into bitmap data and sent to all the slave modules 100. The master module 1 sends a grid start signal, display position information, and scroll speed information to all the slave modules 100, and the slave module 100 performs one grid scan each time it receives a grid start signal. Thus, the display timings of the respective slave modules 100 can be made even.

Description

Display device

FIG. 1 is a diagram showing an outline of the overall configuration of a display device of the present invention. FIG.

FIG. 2 is a circuit block diagram showing the detailed configuration of the master module of the display device of the present invention. FIG.

FIG. 3 is a circuit block diagram showing the detailed configuration of the slave module of the display device of the present invention.

FIG. 4 is a diagram showing the configuration of the display means of the display device of the present invention.

FIG. 5 is a diagram showing the timing of the grid scan pulse when the scroll speed is changed in the display device of the present invention. FIG.

FIG. 6 is a diagram showing a configuration of a conventional display device.

DESCRIPTION OF THE REFERENCE NUMERALS

1: Master module 10: Module control means

13, 22: CPU 50: display means

100: Slave module 200: Cable

[Technical Field]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying characters and symbols, such as news and advertisements.

[0003]

As a display device of this kind, a display device described in Japanese Patent Laid-Open Publication No. 6-19424 is known. FIG. 6 shows the configuration of the display device. The display device 301 includes a controller 302 and a plurality of (six in the figure) cascade-connected modules 303.

From the control unit 302, display data is sent to all the modules 303 in parallel. Each module receives the display data of the portion to be displayed by its own module 303 among the display data sent from the control unit 302 and displays it on the display means provided.

In this case, selection of the display data to be displayed by the own module is performed by recognizing how many modules are connected and selecting display data. Therefore, the display device 301 has a configuration for recognizing how many modules are connected to each other.

That is, the control unit 302 outputs a trigger signal of a predetermined cycle to the trigger signal line and applies the trigger signal to all the modules 303. At the same time, the control section 302 applies the control signal of "H" to the module No. 1 which is initially connected.

The module No. 1 receives a control signal in synchronization with an applied trigger signal, and synchronizes with the trigger signal applied in the next period to generate the next module number. Quot; H " Furthermore, 2 receives the control signal in synchronization with the applied trigger signal, synchronizes with the trigger signal applied in the next period, The control signal of "H"

Thus, the control signal 304 of "H " is transmitted to the cascade-connected module 303 so as to proceed by one trigger signal.

Thus, each module 303 counts the number of trigger signals until the control signal 304 of "H " is applied, and by adding +1 to the count value, it is possible to know the number of its own connection.

In addition, the module No. of the final stage. 6 is input to the control unit 302 and the control unit 302 counts the number of trigger signals until the control signal 304 of "H" is applied to thereby determine the number of cascade connections of the module 303 .

[Problems to be solved by the invention]

In the above-described conventional display device, characters or symbols such as news and advertisements are displayed, but characters and symbols displayed on such a display device are generally scrolled and displayed. At this time, each module 303 receives bitmap information of scrolled characters or symbols from the control unit 302, and displays the characters or symbols scrolled by the built-in display control means on the display means. In this case, it is conceivable to give a synchronous clock to synchronize between the modules. However, since it is difficult for the display device to provide a synchronous clock by laying a long line as a large size, each module performs display control at its own timing have.

Then, the scrolled characters and symbols are displayed by the independent display control means in each module, so that the display timings are deviated from each other and the display screen becomes difficult to see.

In order to change the speed of scrolling, the scanning frequency of the display means is made constant and the number of shifts in dot units of the bitmap information of characters and symbols to be rewritten in this scanning cycle is changed. Therefore, There is a problem in that it is seen or duplicated.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a display device in which letters or symbols to be displayed are rendered natural even when scrolled.

[MEANS FOR SOLVING THE PROBLEMS]

In order to achieve the above object, a display device of the present invention includes a plurality of cascade-connected slave modules each having display means of a predetermined display unit and display control means for performing display control of the display means, And a master module connected to a head of the slave module, the master module including display control means for performing display control of the display means and module control means for controlling the plurality of slave modules, And the display of the display means is started in response to the scanning start signal output from the control means.

In the display device according to the present invention, the master module sends all the display data to the display control means of the slave module and the master module prior to display, and the plurality of slave modules And the display data to be displayed in the transmitted display data is selected and displayed in accordance with the connection order of the modules, and when the display information displayed on the display means is scrolled, The display information is shifted by one dot and the scrolling speed of the display information displayed on the display means is varied by making the duty of the scanning pulse for scanning the display means constant and varying the scanning frequency .

According to the present invention, since timing for starting display by the slave module is transmitted from the master module to the slave module, display timing of each slave module does not deviate, and natural display can be performed.

Further, when characters or symbols are scrolled with a display device, in the experiment, when characters or symbol data to be displayed are shifted one dot at a time of one scanning of the display means, scroll display is naturally performed.

Therefore, according to the present invention in which the display data displayed on the display means is shifted by one dot every one scan, it is possible to perform natural display even in the case of scroll display.

BRIEF DESCRIPTION OF THE DRAWINGS Fig.

Fig. 1 is a conceptual diagram of the configuration of an embodiment of the display device of the present invention.

In this figure, slave module # 1, slave module # 2, slave module # 3, ... The slave module #n is cascade-connected via the cable 200, and the master module 1 is connected to the first-stage slave module # 1. The master module 1 and the plurality of slave modules 100 connected in cascade are provided with display means 50, respectively. The number of slave modules is 20, for example.

The display means 50 is not limited to a fluorescent display tube, but will be described as a fluorescent display tube in the following description.

As will be described later, the master module 1 and each slave module 100 are provided with display control means for performing display control for displaying characters and symbols on the display means 50. The master module 1, A module control means for sending display data or the like to the slave module 100 and sending a display timing signal is further provided.

The display data is input from the external device connected to the connector 10 (CN0) via the communication interface (for example, RS-485) to the master module 1 in JIS code or the like. The master module 1 converts character data or the like into bitmap data and transmits bitmap data of characters or symbols to all slave modules # 1, slave modules # 2, slave modules # 3, ... To the slave module #n.

The bitmap data of characters or symbols sent to the slave module 100 corresponds to all the character data displayed on the display device, and can be several hundred to several thousands of characters. The slave module 100 stores bitmap data of characters or symbols sent to the memory.

The cable 200 includes at least a data bus, an address bus, and a control line. When the power is turned on, each slave module 100 recognizes the number of its slave modules 100 connected thereto. This recognition method is performed by using the control line and the recognition method described in the above-mentioned Japanese Patent Laid-Open Publication No. 6-19424.

In this way, each slave module 100 recognizes how many slave modules 100 are connected, and the slave module 100 in the bitmap data of characters and symbols stored in the memory must display The bitmap data to be read is read out and displayed on the display means 50. [ This control is performed by the display control means incorporated in each slave module 100. [

When the grid scanning start signal of the display means 50 made up of the fluorescent display tube is transmitted from the master module 1 by the control line, the display control means performs only one scanning of the grid scanning, The grid scanning operation is put in the waiting state until receiving the grid scanning start signal. Further, the grid scanning start signal is outputted from the master module 1 every predetermined period, and when the scroll speed is changed, the predetermined period is changed and the scroll speed information is also outputted at the same time.

By the way, when scrolling display is performed, the bitmap information is shifted by one dot per one grid scan, but this shift control is also performed by the display control means. In this case, the master module 1 outputs display position information and scroll speed information indicating display positions of bit map data shifted every one grid scan to the slave module 100 ).

The scroll speed of the display device is determined by the grid scan frequency. When the scroll speed is changed, each slave module 100 scans the grid at a grid scan frequency according to the changed scroll speed. At this time, the duty of the grid pulse supplied to each grid of the display means 50 does not change. When the scroll display is not to be performed, it is preferable to send the display position information to be constant.

The cycle of sending the grid scanning start signal is a period in which the timing at which all the slave modules 100 finish the grid scanning is determined. In this case, it is also conceivable that the master module 1 receives the interception stop signal for one grid scan from each slave module 100 and sends a grid scan start signal when the scanning of all the slave modules 100 is completed . However, since the number of dependencies of the slave module 100 is, for example, 20 stages, the number of interruptions increases, which is not realistic.

Next, an example of a circuit block diagram showing the detailed configuration of the master module 1 is shown in FIG.

In this figure, the module control means 10 controls the slave module 100. The character data displayed on the display device input from the communication line via the connector CN0 is transmitted to the communication interface (IF) 11, And the CPU 13 writes the character data into a rewritable memory (S-RAM) 14. The CPU 13 writes the character data in a rewritable memory (S-RAM) A program for performing control operations by the CPU 13 is stored in a read-only memory (P-ROM) 15, and by executing this program, hundreds to several thousands of character data And then the Chinese character ROM 16 is referred to, and character data is converted into bitmap data. The obtained bitmap data is written in the S-RAM 14.

The bit map data are sequentially read from the S-RAM 14 under the control of the CPU 13 and input to the CPU 22 for display control via the bus 17, the selector 21 and the bus 18, The CPU 22 executes the program stored in the P-ROM 24 and writes the bitmap data to the S-RAM 23. [

In addition, the bitmap data on the bus 18 is output from the connector (CN1) 39 via the buffer 38. [ In this case, a cable 200 connected to the first slave module # 1 is connected to the connector 39.

The CPU 22 receives the grid start signal output from the CPU 13 via the buses 17 and 18 and displays the character or symbol on the display means 50 constituted by the four divided fluorescent display tubes VFD1 to VFD4, Is displayed.

The CPU 22 has an address bus for supplying address signals to the S-RAM 23 and the P-ROM 24, write / read data for the S-RAM 23 and read data for the P-RAM 24 (A-DRIVER1, A-DRIVER2) for latching the bit map data read from the S-RAM 23 to the latch means 26, An anode latch signal ALS for latching the bitmap data, an anode clear signal ALS for clearing the anode drivers 28 and 29 to return them to the initial state, a grid driving circuit 31 for driving the grid of the display device, And outputs the grid scan signals G1 to G4.

The bit map data latched in the latch means 26 is converted into a serial signal by the parallel / serial (P / S) conversion means 27 and serially input to the cascade-connected anode drivers 28 and 29. A shift register is built in the anode drivers 28 and 29, and the bitmap data in series with the shift register is shifted.

In addition, the grid drive circuit 31 simultaneously drives four grids of the four fluorescent display tubes (VFD1 to VFD4), one at a time. The fluorescent display tubes VFD1 to VFD4 each have, for example, four grids, and have sixteen anodes perpendicular to the four grids.

4 shows an example of the configuration of the display means 50 made up of the fluorescent display tubes VFD1 to VFD4. Fig. 4 (a) shows the overall structure and Fig. 4 (b) The sun of the dot is shown.

The display means 50 is 16 x 16 dots and one character is displayed. Each of the fluorescent display tubes VFD1 to VFD4 has a pixel number of 4 dots in the horizontal direction and 16 dots in the vertical direction as shown in Fig. 4 (b). Four grids are provided in the vertical direction, and sixteen anodes are provided in the horizontal direction. When these four grids are GRID1, GRID2, GRID3 and GRID4, scanning pulses as shown in Fig. 5 (a) are sequentially supplied.

In this case, four scanning pulses shown in FIG. 5A are sequentially applied to each of the grids GRID1, GRID2, GRID3 and GRID4 of the fluorescent display tubes VFD1 to VFD4, One grid scan is performed.

As described above, if scanning is performed with four scanning pulses instead of sequentially scanning sixteen grids in total, the duty of the display means 50 to emit light becomes large, and the luminance can be improved. Particularly, in the case of a display device installed outdoors, this driving method is suitable.

The grid drive circuit 31 performs one grid scan by the four scan pulses as described above, and in synchronization with this, the anode drivers 28 and 29 supply drive signals corresponding to the bitmap data to the anode. In this case, since the four grids GRID1, GRID2, GRID3, and GRID4 of the respective fluorescent display tubes VFD1 to VFD4 are driven at the same time, the number of dots driven by one scan pulse is 4 x 16 = 64 Dots. For this reason, the cascaded anode drivers 28 and 29 supply bitmap data for 64 dots to the anode. That is, the anode drivers 28 and 29 output a total of 64 bits.

An anode clock (ACK) defining the timings of the anode drivers 28 and 29 is generated by a counter 30 that divides a clock of 16 MHz.

The power source for operating the master module 1 is supplied with + 5V and + 24V to the connector CN4, +5 V is supplied to the logic section and +24 V is supplied to the DC / DC converter 37, Ebb and Ecc voltages and filament voltages Ef1 and Ef2 for driving the fluorescent display tube to emit light by the DC converter 37 are generated.

In a master module 1, a line extending in one direction substantially parallel to the bus 18 is a line for knowing the slave module 100's slave number. Since the connector CN2 is a connector to which the front end is connected, it can be omitted.

3, the configuration of the slave module 100 is different from that of the master module 1 in that the slave module 100 is not provided with the configuration of the module control unit 10, Respectively. Therefore, although the description is omitted, a module at the front end is connected to the connector CN2, and a module at the next end is connected to the connector CN1. As a result, data and commands transmitted from the master module 1 are sequentially transmitted to the slave module 100.

In addition, a line in one direction installed parallel to the bus 18 is a line for knowing to which of the slave modules 100 the slave module 100 is connected, that its slave module 100 is connected.

Next, the operation of the display device to which the slave module 100 connected in multiple stages to the master module 1 configured as described above is connected will be described.

When the power is turned on, the module control means 10 of the master module 1 outputs a control signal and a trigger signal of a specific level through the line to the slave module 100 to which the slave module 100 is cascaded, By counting the number of trigger signals until the level of the signal changes, each slave module 100 recognizes how many of its modules are connected.

Subsequently, a large number of character codes are supplied from the communication line through the connector CN0 and the communication interface 11 to the master module 1 before the display is started, and the supplied character codes are referred to the Chinese character ROM 16, Data. Then, all of the converted bitmap data is sent to the CPU 22 which performs the display control operation in the master module 1 via the bus 18 and is written in the S-RAM 23. [ Simultaneously, all the bitmap data is sent to the CPU 22 which performs the display control operation in the slave module 100 cascaded via the bus 18, the buffer 38 and the connector 39, and the S-RAM ( 23). The CPU 23 controls the above operations.

Subsequently, the CPU 13 transmits display position information indicating which part of the bitmap data is displayed, and scroll speed information to the CPU 22 of the master module 1 and the slave module 100 send. The CPU 22 in each module receives this and reads the bitmap data of the corresponding place from the S-RAM 23 according to the display position information and the number of self-connection, and sends it to the latch means 26. The bit map data latched by the latch means 26 is converted into serial bit map data by the P / S conversion means 27 and stored in the anode drivers 28 and 29.

The CPU 22 outputs a four-phase grid scanning signal to the grid driving circuit 31 and controls the anode drivers 28 and 29 to control the grid driving circuit 31 and the anode driver 28 And 29 to scan the respective grids of the fluorescent display tubes VFD1 to VFD4 and to output a signal for driving the anode.

As a result, characters and symbols of the corresponding place are displayed on the display means 50 of each module. Then, when one grid scan is completed, the CPU 22 of each module is put in a standby state for scanning until the next grid scan start signal is given.

Next, the scroll display will be described. For example, it is assumed that a four-phase pulse for scanning the grids (GRID1, GRID2, GRID3, GRID4) of the fluorescent display tubes VFD1 to VFD4 at a certain scroll speed is as shown in Fig.

Here, when it is desired to set the scrolling speed twice, the CPU 13 sends the grid scanning start signal, the display position information indicating which part of the bitmap data is displayed, and the scrolling information that has been doubled to the master module 1 And the CPU 22 of the slave module 100. [ The CPU 22 receives it and causes the grid scanning frequency to be doubled (the period is 1/2) to perform one grid scan. That is, the grids GRID1, GRID2, GRID3 and GRID4 of the fluorescent display tubes VFD1 to VFD4 are scanned by the grid scanning pulse shown in FIG. 5 (b). As a result, the pulse duty of the four phases at the time when the scroll speed is doubled becomes t2 / T2. The duty t2 / T2 becomes equal to the pulse duty t1 / T1 shown in Fig. Thus, the pulse duty of the grid scan pulse becomes equal regardless of the scroll speed. In addition, at the time of scrolling display, the display position information is shifted by one dot for every grid scanning start signal that the CPU 13 gives to the CPU of each module. Therefore, the characters and symbols displayed on the display device 50 of each module are scrolled by one dot per one grid scan, resulting in natural and easy-to-view display.

The period of the grid scan start signal is output from the CPU 13 every period according to the scroll speed after the change.

When the grid scanning period is set to T, each module sets the period (T) in which the period T is divided into five periods (Fig. 5). Then, the grid is not driven in the last 1/5 period width. In this case, when the CPU 13 outputs the next grid scanning start signal at the end of the last 1/5 cycle width, the grid scanning start signal is output after the last grid scanning of each module is finished .

As described above, the slave module 100 is always in a data standby state, and receives all the data sent from the master module 1. [ In this case, in order to distinguish the display data from the command signal, the master module 1 outputs a signal different from the display data and the command signal to the control line. The slave module 100 distinguishes the display data and the command signal from the control line.

The display device is not limited to a fluorescent display tube, and a field emission type display device, an LED display device, or the like can be used.

[Effects of the Invention]

As described above, since the timing for starting display by the slave module is transmitted from the master module to the slave module as described above, the timing of each slave module does not deviate from that of the slave module, and natural display can be performed.

Further, in the case of performing a scroll display of characters or symbols on the display device, according to the experiment, the displayed character or symbol data is shifted by one dot each time the display means performs one scan, and the scrolling is naturally performed.

Therefore, according to the present invention in which the display data displayed on the display means is shifted by one dot every one scan, it is possible to make the scroll display look natural even when the scroll display is performed.

Claims (3)

A plurality of slave modules connected in cascade and having a master module connected to the head of the slave module, the slave module comprising: a display module having a display unit of a predetermined display unit (correcting); and display control means for performing display control of the display unit The display device according to claim 1, wherein the master module comprises display means in a predetermined display unit, display control means for performing display control of the display means, and module control means for controlling the plurality of slave modules, Receives the scanning start signal output from the module control means and starts displaying the display means. 2. The display device according to claim 1, wherein the master module sends all the display data to the display control means of the plurality of slave modules and the master module prior to display, and the plurality of slave modules Therefore, the display data to be displayed among the sent display data is selected and displayed. The display device according to claim 1 or 2, wherein, when scrolling the display information displayed on the display means, the display information displayed on the display means is shifted by one dot for each scanning, And the scrolling speed of the display information displayed on the display means is changed by making the duty of the scanning pulse to be performed constant and varying the scanning frequency.