JPH0128388B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is directed to a CRT (Cathode Ray Tube).
This invention relates to a drive device used for interfacing with a CRT in a pattern display device using a CRT (referred to as a CRT).

2. Description of the Related Art Conventionally known pattern display devices include a monochrome display CRT and a color display CRT. In order to be applicable to both of these CRTs, the driving device is provided with circuits that generate a black and white display signal and a color display signal separately and independently.

Therefore, the operator selects and operates one of the circuits depending on the CRT used. For example, when using a CRT for color display, this circuit creates eight color information signals by combining three color information of red (R), blue (B), and green (G), and displays the color. I am now able to do this.

On the other hand, when a monochrome CRT is used, each pixel can only be displayed at a single level, resulting in two-color display of white and black.

Problems to be Solved by the Invention When a color display CRT is used, the displayed pattern can be expressed in eight colors, so the recognition of the pattern is not so great. However, for black and white
When using a CRT, only two colors, white and black, can be displayed as described above. Therefore, in this type of device, it has been desired to display three-dimensional patterns when recognizing more complex patterns.

The present invention has been made to meet such demands, and an object of the present invention is to provide a drive device that is capable of displaying a complex three-dimensional pattern on the display surface of a CRT for monochrome display.

Means for Solving the Problems In order to achieve the above object, the pattern display driving device of the present invention includes a pattern memory storing a pattern code representing a pattern to be displayed on the display screen, and a pattern display drive device for each pixel on the display screen. a color information memory storing a color information signal specifying a color to be displayed in correspondence with the pattern; means for accessing the pattern memory and the color information memory to read the pattern code and the color information signal; A video signal generation circuit that converts the pattern code read from the memory into a video signal, a gate circuit that masks the color information signal based on the video signal output from the video signal generation circuit, and this gate circuit. a brightness modulation circuit having a brightness converter that generates brightness signals of multiple levels according to the output of the brightness converter, and an output terminal for individually drawing out each output of the brightness converter and the gate circuit. Therefore, the above-mentioned luminance modulation circuit is configured to be usable in common for a CRT for color display and a CRT for monochrome display.

Function The brightness converter in the pattern display driving device of the present invention operates to change the brightness of the video signal that drives the CRT depending on the state of the output signal from the preceding gate circuit. As a result, it is possible to display a change in brightness according to color information on a monochrome display CRT.

Embodiment Hereinafter, an embodiment of the pattern display driving device of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of the main parts for explaining this embodiment, including a pattern memory 1 and a color information memory 2.
, a scanning line control circuit 3, and a video signal generation circuit 4
A brightness modulation circuit 9 is composed of a gate circuit including a set of three AND gates 5 to 7, and a brightness converter 8.

The pattern memory 1 and color information memory 2 are as follows:
The data stored in each is individually read out by a control signal synchronized with raster scanning output from the scanning line control circuit 3.

A pattern code signal _E0 representing a pattern to be displayed is read out from the pattern memory 1, and a video signal that can drive a CRT based on this signal _E0 is read out.
_E1 , that is, a video signal _E1 of a serial pixel column for each pixel forming a display pattern is output from the video signal generation circuit 4.

This video signal _E1 is input to one input terminal of each of AND gates 5-7. Also, these
The other input terminals of the AND gates 5 to 7 receive each color information signal E ₂ , which is read out from the color information memory 2 .
E ₃ and E ₄ are simultaneously input in parallel to their corresponding terminals. These color information signals E ₂ , E ₃ ,
_E4 may be a code signal representing one of the three primary color combinations, or may be a CRT for color display.
The signal may be a signal corresponding to each of the three primary colors R, G, and B, which can directly drive the signal. Here, for ease of understanding, each color information signal is
E ₂ , E ₃ , and ₄ will be explained below, taking as an example a case where a color information signal that can directly drive a color display CRT is used.

The timing given to the other input terminal is the timing for each pixel of the serial signal _E1 , which is input simultaneously in parallel.

As a result, a set of output signals E ₅ to E 7 from AND gates 5 to ₇ are color information signals E 2 , E 2 and E ₇ corresponding to the three primary colors.
The color is output as a display signal for each pixel based on the combination of E ₃ and E ₄ . Output terminal 1
1 to 13 are color signal output terminals for extracting this display signal, and the above-mentioned set of output signals E ₅ to
Connect E ₇ to CRT for color display from these terminals 11 to 13.
It can also be supplied as a driving video signal.

Therefore, by using these output terminals 11 to 13, it is possible to display a pattern in color corresponding to the video signal _E1 .

By the way, in the present invention, a set of output signals _E5 to E7 output from the AND gates 5 to ₇ is also input to the brightness conversion circuit 8 as a brightness control signal.

This luminance conversion circuit 8 outputs a serial luminance video signal E ₈ for each pixel having a luminance level corresponding to the signal state of the output signals E ₅ to E ₇ , that is, the above-mentioned display color.

As a result, this luminance video signal _E8 is extracted from the output terminal 10, and can be supplied from this output terminal 10 to the CRT for monochrome display as a driving video signal.

This means that the luminance conversion circuit 8
The color information signals E ₂ , E ₃ , E ₄ read out from
As mentioned above, whether it is a signal that can directly drive a color display CRT or a code signal that represents one of the combinations of the three primary colors, this color information memory 2
This means outputting a serial brightened video signal _E8 for each pixel, which has a brightness level corresponding to the displayed color, in accordance with the color information stored in the display color. In this case, the luminance conversion circuit 8 is realized by appropriately modifying a known circuit according to the form of color information stored in the color information memory 2.

Therefore, by using this output terminal 10, it is possible to obtain a display signal with a pattern corresponding to the video signal E ₁ , and to change the color when displaying in color using the color information signals E ₂ , E ₃ , and E ₄ . It is possible to display each pixel with a brightness level corresponding to the density.

On the other hand, the already mentioned pattern memory 1 and color information memory 2 store coded pattern data to be displayed and
The color information is written at any time. Here, in the present invention, as already mentioned, coded color information (R, G, B) outputted to a color display CRT may of course be input to the color information memory 2. It is.

In this case, the color information signals E ₂ , E ₃ , and E ₄ are red and red, respectively.
AND gate 5 which becomes blue and green color signals and corresponds to
7 is input. At this time, the pattern code signal E ₀ read out by the control signal instructing the raster scanning line at the position desired to be displayed is converted into the video signal E ₁ and sent to the AND gate 5 as described above.
~7 is output as a control signal for closing. As a result, the logical product of the video signal E ₁ and each R, G, B color information signal is taken, and a set of combination results of a total of 8 types of code signals E ₅ to E ₇ is obtained as a code signal according to the color information. It is input to the luminance conversion circuit 8 as a. Therefore, the luminance conversion circuit 8 converts the serial luminance video signal E 8 for each pixel into voltage levels representing eight types of luminance based on the code signals E _{5 to} E ₇ for black and white display. The signal is output to the output terminal 10 as a driving signal for the CRT.

Effects of the Invention As described above, according to the present invention, for black and white display
Patterns can be displayed on the CRT screen at eight brightness levels corresponding to the color information, making it easier to distinguish between light, dark, and dark, allowing for more patterns and three-dimensional patterns. can be displayed.

Furthermore, since color information is converted to black and white information, the same information can be displayed in either color or black and white.

In this embodiment, the luminance information is 3-bit parallel R, G, B for driving CRT for color display.
Although we presented an example in which color information signals can be used for both color display and black and white display, color signal output terminal 1
For black and white display, any combination can be made depending on the brightness to be displayed by omitting 1 to 13.
It also becomes possible to use it in a pattern display drive device exclusively for CRT.

It is also obvious that an ordinary character/figure generator may be used as the pattern memory 1. In addition, for black and white display
Color tape or color belts are installed on the CRT screen to change the bright spots on the screen to a predetermined color.
It goes without saying that the present invention can be fully applied to CRTs or CRTs having monochrome fluorescent screens.

[Brief explanation of drawings]

FIG. 1 is a block diagram of essential parts of a pattern display driving device showing one embodiment of the present invention. 1...Pattern memory, 2...Color information memory, 3...
Scanning line control circuit (reading means), 4... Video signal generation circuit, 5-7... Gate circuit, 8... Brightness converter, 9... Brightness modulation circuit, 10... Output terminal, 11-
13...Color signal output terminal, _E0 ...Pattern code signal, _E1 ...Video signal, _E2 , _E3 , _E4 ...Color information signal,
_E5 , _E6 , _E7 ...Brightness control signal, _E8 ...Video signal with brightness.

Claims (1)

[Claims] 1. A pattern memory that stores a pattern code representing a pattern to be displayed on a display screen, and a color information signal that specifies a color to be displayed corresponding to one pixel on the display screen. a color information memory; means for reading out the pattern code and color information signal by accessing the pattern memory and the color information memory; and a video signal for converting the pattern code read from the pattern memory into a video signal. a generating circuit; a gate circuit that masks the color information signal based on the video signal output from the video signal generating circuit; and a luminance converter that generates multiple levels of luminance signals according to the output of the gate circuit. By providing output terminals for individually drawing out the respective outputs of the luminance converter and the gate circuit, the luminance modulation circuit can be used as a CRT for color display and a CRT for monochrome display. A pattern display driving device characterized in that it can be used commonly for both.