JPH0497387A - Driving device for plane display board - Google Patents

Abstract

PURPOSE:To execute specified display while keeping a brightness balance between screens by constituting a device so that scanning is successively performed in a different scanning cycle every screen and display data is outputted by timing to the scanning. CONSTITUTION:This device is provided with one or plural memories(S-RAM) 5 which store the screen data of every screen having a different display state such as display by plural emitted light colors or graphic and segment display, and a control part which segments or divides the space of the memory and writes the display data in the memory 5. Then, a function for reading out the display data on every screen by switching the space of the memory in order and accessing the data which is written after it is segmented or divided and transmitting it to anode drivers 11 and 16 provided for every screen, and a control part which actuates the grid drivers 12 and 17 for every screen in the different cycles are provided. Then, the scanning is successively performed in the different scanning cycle every screen and the display data is outputted by timing to the scanning. Thus, the specified display is executed on a multicolor fluorescent display tube or a composite fluorescent display tube while keeping the brightness balance between the screens.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a drive device for a flat display panel, and particularly to a multicolor display fluorescent display tube or a graphic screen that constitutes a screen divided by two or more emitted colors. Multi-color display or composite display by collecting light emitting display tubes or multiple fluorescent display tubes to form a screen divided into two or more types of display formats such as segment screen, graphic screen and dot character after screen, dot character screen and segment screen, etc. The present invention relates to a drive device for a flat display panel, which includes a display screen, its drive circuit, and a screen memory for storing screen data.

[Conventional technology]

Conventionally, this type of fluorescent display tube is a multicolor fluorescent display tube that can display a graphic display with luminous colors that can be divided into blue-green, yellow, or red on one screen, or a graphic screen and a display pattern of numbers, symbols, etc. There are composite display tubes with segmented screens.

To drive these fluorescent display tubes, static drive and dynamic drive can be considered as in the case of monochrome or non-composite fluorescent display tubes, but the dynamic drive described below is generally used to display a graphic screen. There is. The conventional example shown in FIG. 5 shows a device for dynamically driving a fluorescent display tube 1 with a multicolor display consisting of 144 x 32 dots per screen, emitting blue-green light with 128 x 32 dots and red light with 16 x 32 dots. The screen data 2 of the fluorescent display tube 1 is designated by the address shown in FIG. 6, and is divided into a blue-green display section 3 and a red display section 4. AO~A9 address data and display data DO~
D7 corresponds to device input signals AO to A9 and Do to D7, and this address data is written into the 5-RAM 5 having a memory space for one screen or more by signals C3 and WR. Data selector 6 is connected to device manual signal AO~
A9, the three-state buffer 7 is opened, and data DO to D7 are written to the 5-RAM5.
The data selector switches to the address specified by the internal counter section 8, and the three-state buffer 7 becomes high impedance. The counter section 8 counts at the period of the oscillation section 9, sequentially designates addresses AO to A9 in FIG. 6, and outputs predetermined data Do to D7 from the 5-RAM 5. The control unit 13 is a parallel-to-serial converter 1 for data Do to D7.
0 to serial data to anode driver 1
At the same time, a signal is sent to the grid driver 12 to sequentially scan the columns designated by A2 to A9 in FIG. 6 from OOH to 8FH. With this machine, both the blue green display section 3 and the red display section 4 are connected to the grid driver 1.
The data DO~D are sequentially scanned at the same period by a shift register inside 2 and inputted in accordance with the scanning timing.
7, a predetermined display is made.

[Problem to be solved by the invention]

However, in general, the luminous efficiency of a phosphor that emits blue-green light and that of a phosphor that emits red light are lower; therefore, when both light-emitting parts are sequentially scanned at the same period, the brightness of the red display part 4 is Since there is a problem that the power Eb of the red display section becomes low, the power Eb of the red display section must be adjusted to balance the brightness.
Another disadvantage is that Ec must be increased and a new power source must be prepared. In addition, when driving a composite fluorescent display tube having a graphic section and a segment section in addition to different emitted light colors, it is necessary to take the same measures as described above in order to balance the brightness.

[Means to solve the problem]

The drive device for a flat display panel of the present invention includes one memory (S-RAM) that stores screen data for each screen having a plurality of emitting colors or display formats, and a memory space divided into this memory to store display data. It accesses the data written separately from the writing control unit by switching the memory space in order, sends the display data for each screen to the anode driver provided for each screen, and operates the grid driver for each screen at different cycles. It has a control section, and by sequentially scanning each screen at a different scanning period and outputting display data in accordance with the scanning timing, a predetermined display can be displayed with brightness balanced between the screens.

In other words, it is a directional display board that uses at least one flat display board to create a screen that is divided into a plurality of luminescent colors, or a flat display board that creates a screen that is divided into multiple display formats using at least one or more flat display boards. In a device for driving a flat display board that has means for reading and writing display data into a screen memory whose address is set to correspond to the position of the smallest light emitting unit that makes up the screen, one screen memory in which the memory space is divided for each divided screen. It has means for sequentially switching and accessing the divided memory spaces to read out display data, and means for changing the readout speed of display data by changing the access speed.

In addition, the drive device for a flat display board of the present invention includes a plurality of memories (S-RAMs) that store screen data for each screen having a plurality of emitting colors or display formats, and control for dividing and writing data into these memories. It has a control unit that reads the data written separately and sends it to the anode driver provided for each screen, and operates the grid driver for each screen at different cycles, so that each screen is sequentially scanned at a different scanning cycle. In addition, by outputting display data in accordance with the scanning timing, a predetermined display can be displayed with brightness balanced between screens. In other words, a flat display board constitutes a screen divided into a plurality of luminescent colors by at least one flat display board, or a flat display board constitutes a screen divided into a plurality of display formats by at least one flat display board. In a device for driving a flat display board, which has means for reading and writing display data into a screen memory whose address is set to correspond to the position of the smallest light emitting unit constituting the screen, at least one screen memory is provided for each divided screen, and the screen is divided into sections. The screen memory is accessed at different speeds for each screen, and the readout speed of display data is changed.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 shows a device for dynamically driving a multicolor graphic fluorescent display tube according to a first embodiment of the present invention. The screen data 2 of the multicolor display graphic fluorescent display tube 1 is designated by the addresses shown in FIG. 6, and is divided into a blue-green display section 3 and a red display section 4. The address data of AO to A9 and the display data DO to D7 are the device input signals AO to A9. D
o to D7, and this address data allows C3,
Written by the WR signal. 5-RAM5 contains the data of the blue-green display section and the data of the red display section A.
By switching the logic of 9, the memory space is divided and written. Data selector 6 is connected to device input signal AO~
Switch to A9, open the three-state buffer 7, and write data DO to D7 to the 5-RAM 5. When the T signal goes high, it automatically enters the read mode, and the data selector 6 uses hexadecimal and octal counters. 8 and the address specified by the binary counter section 14. Also,
Three-state buffer 7 becomes high impedance. The counter section 8.14 counts at the period of the oscillation section 9. The binary counter section 14 changes the bit corresponding to A9 to low and high levels to alternately switch the memory spaces of the blue-green display section and the red display section. The counter section 8 counts in 128 decimal when the blue-green display section is selected, but when the red display section is selected, it counts in 168 decimal notation.
While repeatedly counting in decimals, specify the addresses of the blue-green display section and red display section in Figure 6 in sequence, and press 5-RA.
Predetermined data DO to D7 are output from M5. The control unit switches the data DO to D7 between blue-green display and red display using the data selector 15, and converts the data into serial data using the parallel-to-serial converter 10 and sends it to the anode driver (A) 11 and anode driver (B) 16. At the same time, a signal is sent to the grid driver (A) 12 to sequentially scan the columns designated by A2 to A8 in FIG. Send to grid driver (B) 17. In this way, the blue-green display section 3 and the red display section 4 can be sequentially scanned at different cycles using the shift registers inside the grid driver (A) 12 and the grid driver (B) 17, respectively, and the timing of scanning can be adjusted accordingly. A predetermined display can be displayed with well-balanced brightness using the input data Do to D7.

In the case of this example - column blanking time is 10%
Then, the duty of the blue-green display section is 1/1.
42. The duty of the red display section is 1/17, and the display time per column of the red display section can be approximately 8.4 times longer than that of the blue-green display section. Therefore, conventionally, with a duty of 1/160, the joy and anger of the blue-green display section was reduced to 500 cd/m2, and the brightness of the red display section was reduced to 1.
In order to emit light at 00 cd/m", two power supplies were prepared for the anode voltage Eb of 50 V and 90 V, respectively, but now Eb is 5 V.
Even with a single 0V power supply, the brightness can be sufficiently balanced.

FIG. 2 shows an apparatus for dynamically driving a multicolor graphic fluorescent display according to a second embodiment of the present invention. The screen data 2 of the multi-color display graphic fluorescent display tube 1 is designated by the addresses shown in FIG. 6 and divided into a blue-green display section 3 and a red display section 4. Address data of AO-A9 and display data D○-D7 are device input signals AO-A9.
SRAM (A) 5 that supports DO to D7 and has a memory space of more than one screen with this address data.
A or 5-RAM (B) Written to 5b by signals C3 and W-. S-RAM (A> 5a contains data from the blue-green display section, or 5-RAM (B) 5
The data of the red display part is written into the area b by switching the logic of A9. Data selectors 6a and 6b are switched to device input signals AO to A8, three-state buffers 7a and 7b are opened, and data DO to D7 are transferred to S-RAM (
A) 5a or 5-RAM (B) When the WR signal becomes high level, the child data written in 5b automatically enters the read mode, and the data selectors 6a and 6b use the internal A counter 8.
The address is switched to the address specified by a and B counter 8b. Furthermore, the three-state buffers 7a and 7b become high impedance. The counter section counts at the period of the oscillation section. The A counter section 8a counts by 128, and the B
The counter part 8b sequentially specifies the addresses of the blue-green display part and the red display part in FIG. 6 while counting in hexadecimal.
Predetermined data Do to D7 are output from b.

The control unit converts the data DO to D7 into serial data using the parallel-to-serial conversion unit 10 and sends the data to the anode driver (A).
11 and the anode driver (B) 16, and at the same time send the columns designated by A2 to A8 in Fig. 6 to OOH to 7.
Grid driver (A) sequentially scans signals up to FH
12, and also send the part corresponding to 80H to 8FH to OOH
A grid driver (
B) Send to 17. In this way, the blue-green display section and the red display section 4 are respectively connected to the grid driver (A) 1.
2 and a shift register inside the grid driver (B) 17 can sequentially scan at different periods, and a predetermined display can be displayed with good brightness balance by inputting data DO to D7 in accordance with the scanning timing.

FIGS. 3 and 4 show the form of a display section and the addresses and data assigned to the display section in a third embodiment of the present invention. FIG. 3 shows a composite display fluorescent display screen 18 having a 128.times.32 dot graphic display screen and a 16 digit display constructed of 7 segment mils. The graphics display screen has 128 columns for scanning, plus 1 column for scanning.
It has 6 digit selection electrodes. Segments a to g of the 16-digit part are commonly connected to each digit, and these are data DO to D.
7 (position of AO=O, A1=O). This situation is shown in FIG.

The device for driving this composite display trend display tube can be driven by the device shown in the block diagram of FIG. 1 shown in the first embodiment, and the data corresponding to the blue-green display section of FIG. By writing data corresponding to the red display section in FIG. 1 to the display section 20 and to the segment display section 21 in FIG. 4, a predetermined display can be made on each screen. However, in the case of this embodiment, since the display cells of the segment display section are larger than those of the graphic display section, the amount of light emitted is large. Therefore, the duty of the segment part is balanced by brightness by increasing the count period and decreasing the duty by using a combination of octal and hexadecimal configurations of the counter part 8, contrary to the first embodiment.

〔Effect of the invention〕

As explained above, the present invention includes one or more memories (SRAM) for storing screen data for each screen having a plurality of emitting colors or different display formats such as graphics and segment displays, and a memory in this memory. A control unit that divides or divides the space and writes display data, and a control unit that divides or divides the space and writes the written data by sequentially switching the memory space and reading the display data for each screen. It has a function to send to the driver and a control unit that operates the grid driver for each screen at different cycles, and by sequentially scanning each screen at a different scanning cycle and outputting display data in accordance with the scanning timing. There is an effect that a predetermined display can be displayed on a multicolor fluorescent display tube or a composite fluorescent display tube while maintaining a brightness balance between luminescent colors or different display formats.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a drive device showing a first embodiment of the invention, FIG. 2 is a block diagram of a drive device showing a second embodiment of the invention, and FIGS. 3 and 4 are a block diagram of a drive device showing a second embodiment of the invention. A diagram showing a screen and screen data of a composite display fluorescent display tube showing a third embodiment of
FIGS. 5 and 6 are a block diagram and screen data showing a conventional drive device. 1... Multicolor display graphic fluorescent display tube, 2... Screen data of multicolor display graphic fluorescent display tube, 3... Blue green display section, 4... Red display section, 5 5a
5b...Memory (S-RAM)-66a, 6b
, 15- data selector, 7, 7a7b... three-state buffer, 8, 14... counter section, 8a.
...A counter section, 8b...B counter section, 9...
Oscillation section, 10... Para-serial conversion section, 11.16...
・Anode driver, 12. 17... Grid driver, 13... Control unit, 18... Screen of compound display fluorescent display tube, 1... Screen data of compound display fluorescent display tube, 20... - Graphic display section, 21... segment display section.

Claims (1)

[Claims] 1. A flat display board constituting a screen divided into a plurality of luminescent colors by at least one flat display board, or a screen divided into a plurality of display formats by at least one flat display board. In a device for driving a flat display board, which has means for reading and writing display data into a screen memory whose address is set to correspond to the position of the minimum light emitting unit that constitutes the flat display board and the screen, a memory space is provided for each of the divided screens. It has one screen memory divided into
A drive device for a flat display board, comprising means for sequentially switching over and accessing the divided memory spaces to read out display data, and means for changing the speed at which the display data is read by changing the access speed. 2. A flat display board that configures a screen that is divided into multiple display colors using at least one flat display board, or a flat display board that configures a screen that is divided into multiple display formats using at least one flat display board. A device for driving a flat display board having means for reading and writing display data to a screen memory whose address is set to correspond to the position of the smallest light emitting unit constituting the screen, wherein at least one screen memory is provided for each of the divided screens. A drive device for a flat display panel, further comprising means for accessing the screen memory at different speeds for each of the divided screens and changing the reading speed of display data.