JPS625295A - Multi-screen display unit - 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 [Technical Field of the Invention] The present invention relates to a multi-screen display device having a cursor display function.

[Technical background of the invention]

In recent years, multi-screen display devices, so-called multi-frame screen display devices, have been developed. This multi-screen display device displays a plurality of screens in a superimposed manner according to a predetermined priority order.

FIG. 2 shows an example in which three screens (A), (B), and (C) are displayed in order of priority (A>B>C). Taking the Videotex system as an example, the screen with the highest priority (A) corresponds to the text screen, the screen with the next priority (B) corresponds to the photo screen, and the screen with the lowest priority (C) corresponds to the text screen. Corresponds to the Rusk screen. The character screen is a screen for displaying characters such as kana, kanji, and alphabets.

Further, a photo screen is a screen that displays figures and the like in units of logical pixels (an area defined with a certain width in each direction on orthogonal coordinates). The Rask screen is a rounded screen that identifies and displays a header part (H) and an information part (I) (see FIG. 3) on the screen.

A multi-screen display device displays a plurality of screens in an overlapping manner, as in the above, but if the upper screen is transparent, the lower screen is preferentially displayed.

Incidentally, it is desirable that such a multi-screen display device also be provided with a cursor display function that is often used in graphic displays. Here, the cursor is used to display the display position of characters or the drawing point of figures. In Figure 4, the display position of the character to be drawn next to the character A is shown as "
Examples of displaying with the cursor 11 in the shape of "-" and drawing of a triangle.
An example in which pixel points are displayed with a cross-shaped cursor 12 is shown.

When displaying a cursor on a multi-screen display device, it is necessary to set its priority to the highest level.

As a configuration for setting the cursor priority to the highest level in a multi-screen display device, for example, a configuration as shown in FIG. 5 can be considered.

FIG. 5 shows an example in which the multi-screen display device in the Videotex system described above is provided with a cursor display function. The illustrated device is characterized in that an output section for cursor coloring data is provided independently and given the highest priority.

In Figure 5, 1g, 14, and 16.16 are degrees
This is a data output unit that outputs coloring data D1 s D2 s D3 + D4 for the cursor character screen, photo screen, and rask screen. Reference numeral 17 denotes a cursor display signal generating section that outputs a 1-pit signal indicating whether or not to display a cursor at a display position synchronized with the rask scan. 1B
, 19 and 20 are transparent color detection units that detect whether the colored data DI*Das D3 of the cursor, character screen, and both sides of the photo are transparent data (data indicating a transparent color), respectively. 21 denotes these transparent color detection sections 1B, 19°20
and the output signal of the cursor display signal generator 11, and according to the priority order, the cursor, character screen, photo screen e7
Four colored data D1 on the star screen. This is a selection unit that selectively selects one of the D-DleD4.

Here, the operation shown in FIG. 5 will be briefly explained. First, a case where the cursor is not displayed will be explained.

In this case, the output signal of the cursor display signal generation circuit 11 becomes low level. At this time, the selection unit 21 prohibits the cursor from selecting the colored data D1, and selects one of the three screen colored data D2*Ds t D4. Which one to select depends on the priority and transparent color detection unit 19.2
Determined by the detection output of 0. That is, the output signal of the transparent color detecting section 19.degree. 20 is at the I/I level when transparent data is detected, and is at the low level at other times. When the output signal of the transparent color detection section 19 is low level, the selection section 21 selects the coloring data D of the highest priority character screen, and when the output signal is high level, it selects the coloring data D3 of the next priority photo screen.

Further, if the output signal of the transparent color detection section 20 is also 1/1, and the thumb shift screen is also transparent, the selection of the colored data Ds is prohibited, and the colored data D4 of the lowest rask screen is selected.

Next, the operation when displaying a cursor will be explained. In this case, the output signal of the cursor display signal generating section 17 becomes high level. At this time, the selection unit 21 selects the coloring data DI.
#I) 1 m Prohibits selection of D4 and selects only cursor coloring data Di. However, at this time, if the colored data of the cursor is transparent data, the transparent color detection unit 18
Since the output signal of becomes high level, the selection of the cursor coloring data D is prohibited, and the coloring data Dx of the character screen etc.
e Select one of Da*D4.

Which one to detect is determined by the priority position and transparent color detection section 19.20 of each screen, similar to the mode in which the cursor is not displayed.
determined by the detection output of

Here, each data output section 13, 14 . Is.

The configuration of No. 16 will be briefly explained. First, the cursor data output section 13 will be explained. In FIG. 5, the cursor is displayed, for example, in a flashing manner, blinking at a constant period. Therefore, there are two types of cursor coloring data: one for the foreground color (FG color) and one for the background color (BG color). These are output from the data generation circuit 131,
It is selectively selected by the selector 132 according to the level of the flushing clock (FCK).

There are also two coloring data D2 for the character screen, one for FG color and one for BG color. However, these are the cursor coloring data D! Unlike the color look-up table LUT 144, it is read out in accordance with address data output from the address storage circuit 141 in synchronization with the rask scan. Note that the address data for the FC color and the address data for the BG color output from the address storage circuit 141 are alternatively selected by the selector 142.
LUT 144.

This selection control is performed in accordance with foreground and background identification signals output from the character screen identification signal generation circuit 143 in synchronization with the rask scan.

The data output section 15 for the photo screen also has an address storage circuit 151. Selector 152. Identification signal generation circuit for photo screen IS3
, consisting of 154 LUTs.

, the header part (H) is the coloring data D4 of the rask screen.
There are two types of data: 1 and 2), and these are LUT
They are stored at 162 different addresses, for example, θ address and 111 address. Address data for each address is also output from the address generation circuit 161 in synchronization with the rask scan.

In addition, each of the above coloring data DI * n, l DS *
D4 is 4 bits each for R (red), G (silk), and B (blue), total 1
It is represented by 2 pits.

Here, the operation of the selection unit 21 when the flashing display of the cursor is taken into account will be explained as follows. When displaying a cursor, the output signal ゛ of the cursor display signal generating section 11 becomes high level, as described above. In this case, if neither the colored data D1 for FG nor BG is transparent data, the output signal of the transparent color detection section 18 becomes low level, so that the selection section 21 selects the colored data D1 of the cursor! Select. Therefore, the selection unit 21 outputs coloring data D1 for FG and BG of the cursor alternately, as shown in FIG. 6(&). On the other hand, F
If the coloring data D1 for G is transparent data, as shown in FIG.
As shown in b), three colored data D! y DI
* Any one of D4 and the coloring data Dt for cursor display are output alternately. On the other hand, coloring data D for BG
If 1 is transparent, an operation opposite to that shown in FIG. 6(b) can be obtained, as shown in FIG. 6(C).

[Problems with background technology]

However, as mentioned above, in order to display the cursor, the cursor data output section 13 is replaced by the screen data output section 14.
．． In the case of a configuration provided independently from 15 and 16, there is a problem that the number of priority circuits increases, resulting in an increase in wiring scale, and as a result, the circuit scale becomes extremely large compared to the case where the cursor display function is not added. Accordingly, the reliability of the system decreases.

[Purpose of the invention]

The present invention has been made to address the above-mentioned circumstances, and an object of the present invention is to provide a multi-screen display device that can minimize the increase in circuit scale due to the addition of a cursor display function.

[Summary of the invention]

This invention stores cursor coloring data and coloring data of a specific screen selected from a plurality of screens in one memory,
In accordance with the instruction as to whether or not to display the coloring data of the cursor, the two types of coloring data stored in the memory are selectively selected, and the screen other than the specific screen is colored using the selected coloring data. It is designed to control the selection of data including data.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a circuit diagram showing the configuration of an embodiment of the present invention. In FIG. 1, the same parts as those in FIG. 5 are given the same reference numerals, and detailed explanations will be omitted.

In FIG. 1, LU'l' j 1 contains coloring data D4 of the rask screen and coloring data D! of the cursor. is stored. In this case, among the colored data D4 of the rask screen, the colored data D4 of the header part (H) (see Figure 3)
For example, the coloring data D4 of the information section (I) (see FIG. 3) is stored at address 1. Also in this embodiment, the cursor is displayed in a flashing manner. Therefore, as in FIG. 5, there are two types of cursor coloring data DI, one for FG colors and one for 80 colors, which are stored, for example, at addresses 2 and 3 of the LUT 31, respectively.

32 is a 1-pit output signal S of the cursor display signal generator 17, a 1-bit 7 lashing clock (FCK), and 1-pit transparent identification signals FGTRP and BGT.
This is a cursor identification signal generation unit that outputs a 1-pit identification signal S indicating whether to display (or not to provide) cursor coloring data D1 according to RP.Here, the transparent identification signal FGTR
P indicates whether or not the coloring data D1 for the FG color of the cursor is transparent data (64), and if it is transparent data, it will be low level, and if it is other than transparent data, it will be high level. Similarly, the transparent identification signal BGTRP is
This indicates whether the coloring data D1 is transparent data or not. Since these signals FGTRP and BGTRP are not changed until the primary designation is made, they are detected and output by a microcomputer (not shown). Note that, as described above, the output signal S1 of the cursor display signal generating section 12 is at a high level when a cursor is displayed, and is at a low level when a cursor is not displayed. Furthermore, as is clear from FIG. 6 above, the flushing clock (FCK) is at a high level when the coloring data D for 70 colors is to be displayed, and the coloring data D1 for 80 colors is to be displayed. In this case, it becomes low level. From the above, the output signal S! of the cursor identification signal generation section 32! The level is as follows.

(1) When not displaying the cursor In this case, the output signal S of the cursor display signal generator 17
1 becomes low level, the transparent identification signal FGTRP
, The output signal S3 is always at a high level regardless of the level of BGTRP or the flushing clock (FCK).

(2) When displaying a cursor In this case, the output signal S of the cursor display signal generator 17
Since l is at high level, the level of the output signal S2 is determined as follows according to the levels of the transparent identification signals FGTRP, BGTRP and the 7 lashing clock (FCK).

(2-1) When none of the cursor coloring data D1 for FG color and 80 colors is transparent data In this case, regardless of the level of the 7 lashing clock (FCK), the output signal S! is always at low level.

(2-2) When the coloring data DI for FG color is transparent data In this case, the 7 lashing clock (FCK) becomes the output signal S as it is.

(2-3) When the coloring data Dl for BG color is transparent data In this case, the output signal a= is the flashing clock (F
CK) is inverted.

Reference numeral 33 denotes a selector for selectively reading out the two colored data DI a n stored in the LUT 31 . This selector 33 is connected to the cursor identification signal generator 32.
When the output signal S2 is low level, the cursor coloring data D1 is selected, and when it is high level, the raster surface coloring data D4 is selected. More specifically, the output signal S
Snow is low, flushing clock (FCK)
If it is Kahai level, coloring data Dt for FG color! choose,
10 if the flushing clock (FCK) is low level
Select coloring data D1 for color.

Further, when the output signal S is at a high level, the address generation section 16
If the output signal S3 of 1 is low level, the colored data D4 of the header part (H) is selected, and if the output signal S3 is high level, the colored data D4 of the information section CI) is selected.

When the output signal St of the cursor identification signal generation section 32 is at a high level, the selection section 34 selectively selects the output data of the LUTJ44.154.31 according to the priority order and the detection output of the transparent color detection section 18.19. This is the output signal S
This is because AND gate 343 performs normal priority processing from AND dart 341 to AND gate 343 because 3 is at a high level.

In this case, the colored data read from LUT BJ is the output signal S! ) Since it is an image, it is the coloring data D4 of the raster screen as described above.

On the other hand, if the output signal S1 is at a low level, the selection unit 34 selects the colored data read out from the LUT 31, t, 6.
Select the cursor coloring data D1. This is because the output signal S is at a low level, so the AND gate 341,
This is because the output of the gate 342 becomes a low level, and the output of the OR gate 344 becomes a no-repel.

The operations explained above can be divided into modes (1) and (2) and summarized as follows.

First, in the case of (1), if the thumbnail is not displayed, the output signal S! of the cursor identification signal generation section 32! Since this is High Rail, the coloring data D4 of the raster screen is read out from the LUT 31. In this case, if the colored data D of the text screen is not transparent data, the selection unit 34 selects the colored data D8, and if it is transparent data, selects the photo screen colored data D3, which is the next priority. If this colored data Ds is also transparent data, the colored data D4 of the raster screen, which has the lowest priority, is selected.

Next, in case (2), that is, if you want to display the cursor, Toru F! The above three cases (2-1) and (2-2) depend on the levels of the A identification signals FG'rRP and BGTRP.
), (2-3). First, in case (2-1), since the transparent identification signals FGTRP and BGTRP are both at high level, the output signal S3 of the cursor identification signal generating section 32 is at low level. Therefore, the LUT
The cursor coloring data Dl is read from 31,
Further, in the selection section 34, the coloring data J+I)S is selected, and the coloring data D1 is selected. Note that in this case, the colored data D1 read from the LUT 31
depends on the level of the flushing clock FCK as shown in FIG. 6(a), and the selection output of the selection section 34 is also similar to this.

In the case of the next K (2-2), if the coloring data D1 for the FG color of the thumbstick and cursor is transparent data, the output signal of the cursor identification signal generator 32 is exactly the same as the 7 lashing clock FCK. become.

When the output signal S is at a high level, the coloring data D4 for the raster screen is read from L11T31, and when it is at a low level, the coloring data 0 for the 10 colors of the cursor is read out. Further, when the output signal S3 is at a high level, the selection unit 34 selects the LUTs 144, 154, 3 J
Select output data alternatively, and if it is low level,
Since the output data of LUT 31 is selected, selection section 3
The output of 4 is as shown in FIG. 6(b).

Finally, in the case of (2-3), that is, the cursor's 10
When the coloring data DI is transparent data, the output signal S1 of the cursor identification signal generating section 32 is the inverted version of the 7 lashing clock FCK. Therefore, in this case, contrary to the case (2-2), as shown in FIG. 6(c), the coloring data D1 for the FG color of the cursor and the three coloring data D鵞*n, tD4 are combined. One of them is selected alternately.

As detailed above, in this embodiment, the coloring data D4 of the rask screen and the coloring data D1 of the cursor are stored in the same LUT.
31, and selectively selects the above two coloring data D4 and Dl from the LUT 31 depending on whether or not the cursor coloring data D1 is to be displayed.
The data selection operation in step 4 is controlled.

According to such a configuration, the coloring data D for the rask screen
4 and the cursor coloring data Dlt can also be supplied to the selection section 34 in the same way. Therefore, in FIG. 1, the number of transmission lines for colored data can be reduced by 12 pits compared to the previous FIG. Logical dirt can be reduced.

In this manner, in FIG. 1, the number of transmission lines and logic darts for one colored data can be reduced, even if the number of bits for one colored data increases.

The increase in circuit scale can be suppressed as much as possible.

Further, in FIG. 1, the configurations of the selectors 142 and 152 are the same as in FIG. 5, but the circuit scale of the selector 33 can be significantly reduced compared to the selector 132 in FIG. 5. This means that the number of input cap- itlets in the selector 1320 is 25. While the output pits are 12, the number of input pits in the selector 330 is 3. This is because the number of output bits is two.

That is, the selector 32 selects the colored data itself, whereas the selector 33 is a turtle that selects address data for reading out the colored data. In this case, in FIG. 1, the cursor coloring data D1 is fixed to one type of FG color and BG color, but this problem can be solved by making LU'l' j 1 rewritable. . In this case, although a line for rewriting is required, the number of logic gates in the selector 33 can be reduced, and the circuit scale can be reduced compared to that shown in FIG. 5. And the cursor coloring data D
If it is acceptable for 1 to be fixed, a line for rewriting is not required, and the circuit size can be reduced by a large 111K.

On the other hand, in FIG. 5, even if the cursor coloring data D1 is fixed, the structure of this coloring data D1 must be matched to the structure of the other coloring data D, e DI # D4. , the number of input/output pits and the number of logic darts of the selector 1320 cannot be reduced.

In addition, in the above explanation, the cursor coloring data Di and 2
We have explained the case where the colored data D4 of the star screen is stored in one LUT, but the colored data D1 of the cursor, the colored data D of the text screen, or the colored data D of the photo screen are stored in one LUT.
Of course, s may be stored in one LtJT K.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a multi-screen display device that can minimize the increase in circuit scale due to the addition of a cursor display function.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing the configuration of an embodiment of the present invention, and FIG.
Figure 3 shows the screen configuration of a multi-screen display device, Figure 3 shows a part of the header and information section, Figure 4 is a diagram for explaining cursor display, and Figure 5 shows a multi-screen display with a cursor display function. 1 is a circuit diagram showing a configuration currently considered as a screen display device. FIG. 6 is a diagram for explaining the operations of FIGS. 1 and 5. FIG. 14.15...Data output section, 161...Address generation section, 17...Cursor display signal generation section, 31.
... Lookup table, 32... Cursor identification signal generation section, 33... Selector, 34... Selection section.

Claims (1)

[Claims] In a multi-screen display device that displays a plurality of screens in a superimposed manner according to a predetermined priority order, coloring data of a specific one screen selected in advance from among the plurality of screens. data holding means for holding coloring data of the cursor; data outputting means for outputting each coloring data of the screens other than the specific screen among the plurality of screens; and a priority order of the coloring data of the plurality of screens. a transparency judgment device for determining whether the colored data of each screen except the lowest screen is transparent data; a cursor display instruction means for instructing whether or not the colored data of the cursor is to be displayed; data reading means for selectively reading out the coloring data of the specific screen and the coloring data of the cursor from the data holding means based on instructions from the display instruction means; and the cursor display instruction means displaying the coloring data of the cursor. When the instruction is given, the read data of the data holding means is selected, and when the display of cursor colored data is not instructed, the data output means is output according to the priority order and the judgment result of the transparency judgment means. A multi-screen display device comprising: data selection means for selecting any one coloring data from data and data read out from the data holding means.