JPS63244090A - Vector scan/raster scan display device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Emperor 1 Retired Emperor ■J Bean! The present invention relates to a display device that performs both vector scan display and raster scan display.

In raster scanning, a vector scanning method is mainly used to draw symbols, but when it is necessary to simultaneously display an image taken by a camera, etc. and a symbol, uses a raster scan display. As a method for displaying symbols during this raster scan, a configuration is adopted in which, for example, symbols are written in a video memory for graph ink consisting of 512 x 512 pixels, and the written symbols are displayed. has been done. As a writing method, a method called scan conversion is used, in which the address during vector scanning corresponds to the address of the pixel in the video memory, and the vector is written into the video memory. Since the number of pixels is set to be smaller than the number of addresses that can be specified during vector scanning, one pixel of the video memory corresponds to many addresses for vector scanning. Therefore, even if vectors appear to start from the same pixel in video memory, or even if vectors appear to start from the same pixel on vector scan, The starting addresses of the vectors may be different. If this starting address is different,
In the case of diagonal vectors, the pixel positions on the video memory that pass one after another may be two horizontally connected, or may be shifted up or down by one bit.

In other words, even though the same symbol is drawn as a vector, symbols with slightly different shapes are written into the video memory, and the correspondence between the vector scan symbols and the symbols on the video memory is uneven. It had become.

The present invention was devised to solve the above problems, and its purpose is to combine vector scanning and raster scanning to write uniform symbols into video memory without being affected by differences in the starting positions of vectors. The purpose of this invention is to provide a display device.

■ In order to achieve the above object of divination, the vector scan/raster scan combination display device of the present invention provides a vector scan/raster scan combination display device in which characters are represented by vectors, where N is a natural number of 2 or more.
A character memory in which a code is stored in advance, a symbol generator that sends a drawing address signal indicating a character and an unblanking signal according to the output of this character memory, and an NXN (one pixel corresponds to a specific drawing address) of this symbol generator. When the drawing address signal is input as a signal indicating an address and the unblanking signal is input as a signal indicating data, and at least the output of the symbol generator is a diagonal vector, the symbol generator inputs the drawing address N times. and a write control section that sends a write pulse to the video memory each time the video memory is moved.

One pixel of the target video memory is NX for vector scanning.
Since they correspond to N drawing addresses, the two pixels of the video memory corresponding to the starting point of the vector and the drawing addresses from this starting point to N (corresponding to both eyes) are determined by their relative positions to each other. The relationship is fixed, and this positional relationship is not affected by the starting point of the vector.This is common to all pixels corresponding to the a (natural number) XNth drawing address.Based on this property, the write control unit Accordingly, each time the output of the symbol generator moves through the drawing address N times, a symbol is written to the pixel of the video memory corresponding to this drawing address.

Figure 1 is a block diagram showing the electrical configuration of an embodiment of the present invention.

In the figure, a character memory 15 in which a character code indicating a character for display as a vector is stored and a character control section 11 are bidirectionally connected. Signals from an externally provided host computer or the like are input to the character control section 11, and a signal line for outputting a character code is sent out to the symbol generator.

When vector scanning from symbol generator 12 13
Two drawing address signals 121 - Drawing address signal signal 121-X, 1
The lower three bit signals of each of 21-Y are not connected to the video memory 18. In other words, one pixel of the video memory 18 is configured to correspond to 64 (8×8) pixel addresses.

The write control unit 16 receives a clock signal 123 sent from the symbol generator 12, a diagonal vector signal 124 indicating drawing of a diagonal vector, and an unblanking signal 1.
22 has been introduced and sends a write signal 161 to the video memory 18.

A video signal 170 from a camera or the like and the output of the video memo January 8 are guided to the adder 17, and an image signal is sent to the vector rask switching unit 13. The output of the vector rask switching section 13 is guided to a display unit 14 and further sent to a CRT 19.

The operation of the display device according to the present invention will be explained below.

When performing vector scan display, the character code corresponding to the character specified by the external signal line 100 is read from the character memory 15,
It is sent to the symbol generator 12.

The symbol generator draws a pixel vector corresponding to the character code at an address 121-X.

Send it to 121-Y. This drawing vector is sent to the display unit via the vector rask switching section 13 and displayed on the CRT 19.

The operation for writing symbols into the video memory 18 while performing the above operations will be described.

Since one pixel of the video memory 18 corresponds to 8×8 drawing addresses, as shown in FIG. 2, for the horizontal vector v3, eight drawing addresses 1841 correspond to one pixel 184. are doing. This pixel 18
4, eight writes are performed according to eight pulses sent to clock signal 123 while the drawing address moves to 1841-8. The data written at this time is data that instructs the pixels to shine on the CRT 19, for example, 0 pixels 1 which are at H level.
Writing is performed five times in the 0 pixel 181 where similar writing is performed for pixel 85 as well. That is, three pixels 18
11184.185 becomes a shining pixel.

When the same operation as above is performed for diagonal vector v1, all pixels 1 that this diagonal vector v1 crosses
81.184.182.186.183 become pixels that shine. In addition, the diagonal vector v2, which is a diagonal vector starting from pixel 181 but has a different starting point, is 181.18
The pixel 7.182.188.183 becomes the shining pixel, and the starting point is the same pixel 18 for diagonal vectors v1 and v2.
1, they will be stored differently on the video memory 18.

Therefore, when it is indicated by the diagonal vector signal 124 that a diagonal vector is to be drawn, as shown in the timing chart of FIG. and sends a write pulse WPI to the video memory 18. Diagonal vector v1 is from pixel 181 to pixel 184
The next write pulse -P2 crosses the clock signal 123 and moves to the pixel 182.
It is sent out in synchronization with pulse P2, which is eight pulses after counting from 1. When the write pulse meter 2 is sent out, the diagonal vector v1 crosses the pixel 184 and reaches the pixel 18.
The pixel address v1-2 corresponding to 2 has been reached. Therefore, the pixel 182 becomes a shining pixel, and the pixel 184 becomes a blanking pixel. Similarly, when the drawing address becomes vl-3 (when the eighth pulse P3 counting from pulse P2 is sent to the clock signal 123),
The write pulse meter 3 is sent out. Therefore, pixel 181
．． 182 and 183 become pixels that shine.

Also, in the case of the diagonal vector v2, a write pulse is sent to the video memory 18 according to the same timing.

In other words, writing is performed when the drawing address becomes v2-1, v2-2, or V2-3. Therefore, the pixels that light up are 181.182.183, and the same symbols as in the case of the diagonal vector v1 are written into the video memory 18 also in the case of the diagonal vector v2.

As described above, if the diagonal vector starts from the same pixel in the video memory 18, the same symbol will be written to the video memory 18 regardless of the difference in drawing address within the same pixel.

Then, at the time T2 when the sending of the unblanking signal 122 ends, the sending of the write pulse also ends.The output of the symbol written to the video memory 18 in the above manner is added to 100, and the output of the symbol is added to the vector rask switching unit 13. and is led to the display unit 14 through the display unit 14. At this time, a horizontal sweep signal and a vertical sweep signal for raster scanning are sent to the drawing address signals 121-X and 121-Y, and symbols and images are displayed on the CRT 19 by raster scanning.

Note that the present invention is not limited to the above embodiments, and one pixel of the video memory 18 may be assigned to another drawing address or 16
It is also possible to apply the present invention to the case where it corresponds to a drawing address of 16 raster scans.

In addition, the write control unit 16 is configured to send out write pulses in synchronization with the eight daily pulses sent to the clock signal 123 only when drawing a diagonal vector, but when writing a horizontal vector, It is possible to adopt a configuration in which a write pulse is sent out at the same timing when drawing a vertical vector as when drawing a diagonal vector.

Further, if the end point of sending out the unblanking signal 122 exceeds a certain point after sending out the final write pulse, it is possible to adopt a configuration in which an additional write pulse is sent out. However, for determination within a certain period of time, the write pulse is sent only when the number of pulses of the clock signal 123 is, for example, 6 pulses or more. Furthermore, since this write pulse is sent after the unblanking signal ends, a latch section is provided to store the drawing address immediately before the end of sending the unblanking signal 122, and the output of this latch section is given to the video memory 18 for writing. .

λ1 Δ The combined vector scan/raster scan display device of the present invention makes one pixel of the video memory correspond to a NXN drawing address of a symbol generator, and when a diagonal vector drawing address is output, the symbol generator The structure is such that a write pulse is sent to the video memory every time the drawing address is moved.
It becomes possible to write uniformly shaped symbols into the video memory without being affected by the starting position of the vector.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the electrical configuration of an embodiment of the present invention, Fig. 2 is an explanatory diagram showing the relationship between pixels of the video memory and drawing addresses, and Fig. 3 is a timing diagram showing the timing of main signals. It is a chart. 12... Symbol generator, 15... Character memory, 16... Write control section, 18... Video memory, 121-X... Drawing address signal, 12
1-Y...Drawing address signal, 122...
Unblanking signal.

Claims (1)

[Claims] (1) In a display device that uses both vector scan display and raster scan display, when N is a natural number of 2 or more, there is a character memory in which a character code indicating a character as a vector is stored in advance, and the output of this character memory is a symbol generator that sends out a drawing address signal and an unblanking signal indicating the character; one pixel corresponds to N×N drawing addresses of the symbol generator; and the drawing address signal is input as a signal indicating the address; When the unblanking signal is input as a signal indicating data to a video memory and at least the output of a symbol generator is a diagonal vector, a write pulse is sent to the video memory every time the symbol generator moves the drawing address N times. A vector scan/raster scan combined display device comprising: a write control unit that sends out a vector scan/raster scan display device.