JPH02285395A - Character display device - Google Patents

Abstract

PURPOSE:To enable instantaneous screen rewriting, enlargement, and scrolling in the enlargement by enlarging and displaying characters through a character generator and rewriting character codes on a refresh memory for the rewriting of the characters. CONSTITUTION:This display device is equipped with storage means 13-2 and 13-3, a switching means, and a display means. A display control means reads character codes out of the refresh memory 2 and supplies them to character generators 4-1 and 4-2 in order to output character patterns to the storage means 13-2 and 13-3. Those storage means 13-2 and 13-2 output the character patterns to the switching means at the time of lateral enlargement and longitudinal enlargement. Further, a converting means outputs the character address and raster address of the display control means as they are at the time of a standard character display and outputs the character address and raster address after conversion at the time of a longitudinally and laterally enlarged character display. Consequently, the instantaneous rewriting, enlargement, and scrolling of an image plane are performed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a character display device, and particularly to a character display device that displays a plurality of characters of different sizes on one screen.

(Prior Art) Some conventional character display devices generally use a character system or a bitmap system.

FIG. 6(a) is a block diagram showing the configuration of a character display device using the character method. In the same figure (a), l
is a central processing unit (hereinafter abbreviated as CPU) that controls the entire device; 2 is a refresh memory (hereinafter abbreviated as RM) that stores character codes; 3 is a CRT controller (hereinafter abbreviated as CRTC) that controls the display of the CRT; 4 5 is a character generator (hereinafter abbreviated as CG) that outputs a character pattern using character codes, and 5 is a character generator that outputs a character pattern for one line of one character.
Parallel/serial converter circuit that sends out bits one by one (
(hereinafter abbreviated as PS), 6 is a CRT that displays characters,
7 is an oscillation circuit that operates CRTC3 and PS5.

Next, the operation will be explained.

The character code written to RM2 by CPUI is CR
It is read by TC3 and sent to CG4. CG4 outputs a character pattern from this character code. This character pattern is converted into a 1-bit output by the PS5, and outputted to the CRT 6 one bit at a time by the oscillation circuit 7. CRT6
displays this data on the display screen.

To change the displayed characters, the CPU should access RM2 and rewrite the character code.

In a character display device using the character method as described above, the operations of RM2, CG4, and PS5 must be completed within the time it takes for the CRT6 to display one character in the - line. When used for CRT, C
Since the display time of one dot in RT6 is extremely short, there is a problem in that it is difficult to operate these circuits within the display time of one character. Furthermore, it was not possible to use school display to see non-standard areas that are displayed in standard characters and do not fit within the screen when enlarged, which occurs when text is enlarged or enlarged.

In order to solve the above-mentioned problems, the present applicant filed a patent application No. 61-2.
No. 76,668 proposed a character display device that has a plurality of standard and enlarged CGs and can be scrolled by specifying a display address. The structure of the character display device is shown in FIG. In this figure, the same reference numerals as in FIG. 6 indicate the same components.

In the device shown in FIG. 7, two standard CG4-
1.4-2.4 enlarged CGs 4-3 to 4-6 are used. 9-1 to 9-8 are latch circuits that latch input signals at the rising edge of the clock from the oscillation circuit 7. 10-1
-1O-3 are multiplexers (hereinafter abbreviated as MPX) for switching input signals. Reference numeral 11 denotes a path buffer to which the data bus is connected only when the CPUI reads or writes RM2. 12 is a flip-flop (hereinafter abbreviated as F/F); 13 is a read-only memory (hereinafter abbreviated as ROM);
14 is an adder (hereinafter abbreviated as ADD) for specifying an address.

The latch circuits 9-1 to 9-3 are provided between the CRTC 3 and ps5, and latch the display on/off signal of the CRT 6 outputted from the CRTC 3, display control signals such as high brightness, inversion, and blink modes. Latch circuits 9-4 to 9-8 are for latching data. The latch circuit 9-4 is C
Connected between RT3 and MPXlO-1, latches address data (MA) from CRTC3. Latch circuits 9-5.9-6 are connected between RM2 and CG4-1.4-2, respectively, and include even and odd addresses from RM2 and mask address data (RA) from CRTC3.
) are latched respectively. Latch circuits 9-7, 9-8 each latch the character patterns from CG4-1.4-2 and output them to MPXlO-2. Note that the latch circuit 9
-1 and latch circuit 9-4, latch circuit 9-2 and latch circuits 9-5 to 9-6, latch circuit 9-3 and latch circuit 9-
7 to 9-8 each latch the input signal in the same phase.

MPXIO-1 is "CRTC3 address data"
CRTC clock inverted data” (cRTCB side) and “
CPUI address (cPUI side)". This switching is done by the display on/off signal of the CRTC3. When it is on ("1"), the address is on the CRTC3 side, and when it is off, it is on the CPUI side.
Be on your side. M P X 10-2 is a latch circuit 9-7.
CG4-1 input via 9-8.

The character pattern data of 4-2 is switched and output to the PS5. In this switching, when the CRTC clock is 1101+, the output is CG4-1, and when the CRTC clock is 1'', the output is CG4-2.

When the display on/off signal latched by the latch circuit 9-1 is off (O''), the pass buffer 11 outputs the CPUI to W.
When the RITE signal "O" is issued (RM2 is in write mode), the buffer is opened and data (character code) from the CPUI is transferred to RM2.

Further, when the display on/off signal is on (“1”), the buffer is closed and no data is exchanged between CPtJl and RM2.

Next, the operation of the apparatus shown in FIG. 7 will be explained with reference to the timing chart shown in FIG. 8 and the operation diagram shown in FIG. 9.

First, a character code is written into RM2 by the CPUI. That is, when the display on/off signal latched by the latch circuit 9-1 is off, the CPU
0” through the OR gate to set RM2 to light mode,
The character code input from the CPU 1 via the path buffer 11 is written to the address of RM2 input from the CPUI via the MPXlo-1.

Next, a CRTC clock as shown in FIG. 8 is sent to the CRTC 3 by the oscillation circuit 7.

The CRTC 3 starts operating at the rising edge of the CRTC clock, but outputs the address (MA) after a predetermined time (time required for access).

The data is latched by a latch circuit 9-4 for synchronization. This latched data is sent to RM2 via MPXIO-1 along with an inverted version of the CRTC clock. The inverted data of this CRTC clock is RM2
used as the lowest address.

For example, as shown in FIG. 9, if the address of RM2 is set to 0 to n in binary, the CPU 1 can write to/read from the RM2 using its own address, but the CRT
In the case of C3, in order to display two characters in one cycle of the CRTC clock, the addresses 0 to n-1 are set to MPXIO-1.
, that is, input to addresses 1 to n of RM2. and,
Inverted data of the CRTC clock, that is, "0" and "1" are input to the 0 address (lowest order) of RM2.

In this way, when the CRTC clock rises, an even address is input to RM2, and when it falls, an odd address (previous address +1) is input.

As a result, in the one-character address of CRTC3 (cRTC
RM2 outputs character codes for two characters in one clock cycle). Of these character codes, the character codes (a,, b,...) at even addresses are changed to C by the latch circuit 9-5.
CRTC3 indicates each character line at the rising edge of the RTC clock
The character code (a,, b,...) of the odd address is latched together with the mask address (RA) of the latch circuit 9.
-6, it is latched at the falling edge of the CRTC clock. The character code output from the latch circuit 9-5 is output as a character pattern (Am, B2, . . .) by the CG 4-1, and is further latched by the latch circuit 9-7. Similarly, the character code output from the latch circuit 9-5 is output by the character pattern (A, .) by CG4-2.

B, . . . ) and latched by the latch circuit 9-8. The character patterns latched by these two latch circuits 9-7 and 9-8 are output to MPXlo-2. , :(7) When the CRT clock is at a high level, the MPXIO-2 outputs the character pattern data (A,,B,...) of the latch circuit 9-7, and when the CRT clock is at a low level, it outputs the character pattern data (A, B,...) of the latch circuit 9-8. , B, ...) are output to the PS5.

As a result, the two character patterns of CG4-1 and 4-2 are successively output to the PS5. This allows the PS5 to continuously output character patterns to the CRT 6 using the clock of the oscillation circuit 7.

Note that since the display control signal of the CRT 6 outputted from the CRTC 3 is synchronized with the character pattern data by the latch circuits 9-1 to 9-3, no deviation occurs. When rewriting characters, it is sufficient to simply rewrite the character code of RM2 using the CPUI.

Next, the operation in case of enlarged character display will be described.

Here, conditions for standard characters, enlarged characters, and display characters in the conventional example are set as shown in FIG. In other words, if the enlarged characters are doubled in height and width, ■Standard characters... horizontal X dots, vertical Y dots (10th
Figure (a)) ■Enlarged characters: 2x dots horizontally, 2y dots vertically (Figure 10 (b)) ■Displayed characters (standard): 2m characters horizontally, 2n characters vertically (Figure 10 (c)) ■ Display characters (enlarged): m characters horizontally and n characters vertically (Figure 1O (c)).

This condition is so that even if you change from standard characters to enlarged characters, the entire font of the characters will be displayed and parts of the characters will not be missing.

When a signal for enlarged character display is written to F/F12 from the CPU, ROM1 is written under the signal control of F/F12.
3 converts the address signal and raster signal of CRTC3.

FIGS. 11(a) to 11(c) respectively show the address of each character when displaying standard characters, the address of CRTC, and the address of each character when displaying enlarged characters.

In other words, when standard characters are displayed on the screen, the width is 2m characters and the height is 2n characters, so the character address is 4mn from O to 4mn-1.
(Figure 11(a)). Also, since the CRTC3 counts 2 characters horizontally as 1 character, there are m characters horizontally and 2n characters vertically, and the character address is 0 to 2.
It becomes 2 mn of nm-1 (Fig. 11(b)).

Next, regarding the enlarged character display on the screen, in this case both the line and the width are enlarged twice, so there are m characters horizontally and n characters vertically. However, when the address of a character is 0 to m-1 in width, the next address is 2m to 3m-1 (in the case of no scrolling). Furthermore, in this case, since the number of rasters at the same address is doubled (standard y raster→enlarged 2y raster), raster conversion is also required. This conversion is shown in Table 1 below.

Table 1 (blank below) In Table 1, the output address of CRTC3 is Cl~2m
n-1, the output raster is 0-y-', but the ROM13
Therefore, the address in enlarged mode is 0~m-1, 2m~
3m-1...2m(n-1) to (2n-1)m-1, and the raster becomes 0 to 2y-1.

The address and raster are determined as above, and CG4-3
~4-6 works. In this case, when CG4-3 to CG4-6 are accessed, raster 0 to y-1 when standard CG4-1 operates is CG4-3. Raster y to 2y-1 becomes CG4-5. Here, the first method for accessing the CG is
This will be explained with reference to FIGS. 2(a) to 2(d). In FIG. 12, (a) shows the CG4-1.4-2 operation order in the case of standard character display, and ■ indicates the CG4-1.4-2 operation order. ■ is CG4-2
It shows. In this case, assuming that each of CG4-1 and CG4-2 can display one character, (b)
The font content will be like this. Next, for enlarged display (
As shown in b), in this case, CG4-3 to CG4-6 require the operation order of ■ to ■, respectively, and their font contents must also be as shown in (d). Furthermore, (d)
In, ■ to ■ indicate CG4-3 to CG4-6.

Next, a scroll address is also written to the F/F 12 by the CPU. This output is added to the extended address by ADD 14 and output. Figure 5 is an explanatory diagram of sucrose during enlarged display.If you want to enlarge the part marked ■ shown in Fig. 5(a), write O in F/F12, and when the display is enlarged, the part marked ■ will be enlarged. A display is displayed (FIG. 5(b)).

If you wish to enlarge the part marked ■, write the value of (2n-1)m into the F/F 12, and it will be added to the enlargement address by the ADD 14 and displayed (FIG. 5(c)). Similarly, if you want to enlarge the parts of ■ and ■, m and 2n respectively.
Just write m in F/F 12 (Fig. 5(d),
(e) ). Even in this enlarged display, all standard characters can be displayed. It can also be used for vertical and horizontal enlargement in the same way.

Also, if you want to scroll up one line at a time, you can write 2m, 4m, 6m, -2m (n-1) in the F/F 12 in sequence, and if you want to scroll horizontally one character at a time, 1, 2... You can write 3°...m sequentially.

Furthermore, if you want to scroll in the opposite direction, you can do so by decreasing the values written to each F/F 12.

On the other hand, FIG. 6(b) is a block diagram showing the structure of a character display device using the bitmap method. In FIG. 3B, the same reference numerals as in FIG. 1A indicate the same components. Reference numeral 8 denotes a bit map memory (hereinafter abbreviated as BMM) which has a capacity corresponding to all bits of the CRT 6 and stores the character pattern of CG4.

Next, the operation will be explained.

The character code written to RM2 by CPUI is CG
4 is output as a character pattern. The data is written to 8MM8.

The data of 8MM8 read by CRTC3 is sent to PS5.
The signal is converted into a 1-bit output by the oscillation circuit 7 and sequentially outputted to the CRT 6. The CRT 6 displays this data on its display screen.

When changing the displayed characters, perform the following steps from ■ to ■.

■The CPUI rewrites the character code of RM2.

(2) CPU1 accesses RM2 and outputs the character pattern of CG4.

■The CPUI reads the CG4 character pattern.

■The CPUI writes a character pattern to 8MM8.

(Problems to be Solved by the Invention) However, the character display device having the above configuration has the following problems.

The character type character display device shown in FIG. 6(a) has the problem that the operation time is slow (and the size of the characters cannot be changed). However, with these character methods, multiple character generators are required for each type of character, so when displaying other types of characters, the capacity of just the character generator becomes large.
There was a problem in that the cost increased.

On the other hand, in the case of the bitmap method shown in Fig. 6(b), the number of vertical dots of the character can be rewritten by the CPU.
leads RM2, and the character pattern of CG4 is 8MM8
It is necessary to write data to the computer, which increases the load on the CPU.

Furthermore, when rewriting characters, if the CPUI is a 16-bit data bus, the following processing is performed for characters of 24 dots x 24 dots.

■The CPU writes the character code and the line number of that character to RM2.

■CPU1 CGs the character pattern of RM2 character code.
Read 4 to 16 bits three times.

Repeat this 24 times, changing the line numbers.

Furthermore, it is necessary to write the character pattern data into the 8MM8 corresponding to the screen of the CRT6 2×24=48 times. As described above, the bitmap method requires a lot of effort and has the problem that it takes time to rewrite the display.

Furthermore, a character generator was required for each type of character.

The present invention provides multiple types of character generators as described above,
To instantly rewrite, enlarge, and scroll the screen by eliminating the drawbacks of requiring multiple characters (character method) and the drawbacks of requiring too much time to rewrite and display or requiring multiple types of character generators (bitmap method). The purpose of the present invention is to provide a character display device that enables the following.

(Means for Solving the Problems) In order to solve the above problems, the character display device of the present invention has the following features:
A refresh memory that stores character codes, a plurality of character generators that generate standard character patterns corresponding to the character codes, a storage means that converts the output signal of the character generator into an enlarged character pattern, and switches the output of the character pattern. a switching means, a display means for displaying a character pattern on a display screen, and a standard and enlarged character pattern obtained by sequentially supplying the character code read from the refresh memory to each character generator, and each character pattern is switched and displayed by the switching means. A display control means for controlling the display on the display, a conversion means for controlling the conversion of character addresses and raster addresses depending on whether the display is a standard character display or an enlarged character display, and a display control means for controlling the display during enlarged display by specifying a specific address on the display screen. a display area specifying means for specifying the area to be displayed; a raster changing means for specifying the next raster after the displayed raster in the vertical and horizontal enlargement mode and a display raster in modes other than the vertical and horizontal enlargement mode; and converting means that changes the output pattern by switching.

(Operation) The technical means of the present invention operates as follows. The display control means reads out the character codes written in the refresh memory and sequentially supplies them to a plurality of character generators, and the standard character generator works to output character patterns corresponding to the input character codes to the switching means. . The standard character generator also outputs character patterns to multiple storage means for expansion. This enlargement storage means outputs the character pattern to the switching means during horizontal and vertical enlargement. Further, this storage means can convert a character pattern of a standard character generator into a plurality of character patterns and enlarge and display them. The switching means operates to control the display control means by sequentially selecting the output of the standard character generator or the output of the enlargement storage means and outputting character patterns continuously to the display means. −
On the other hand, the conversion means outputs the character address and raster address of the display control means as they are in the case of standard character display, and converts and outputs the character address and raster address in the case of vertical and horizontal enlarged character display. By combining these controls, various character patterns such as standard characters, vertically enlarged characters, horizontally enlarged characters, and vertically and horizontally enlarged characters can be displayed in a mixed manner. Therefore, when rewriting characters, it is possible to instantly rewrite the display screen and select the font by simply rewriting the contents of the refresh memory.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of this embodiment. 1st
In the figure, the same reference numerals as in FIG. 7 indicate identical components. In the device of this embodiment, CG4-3 to CG4-3 in FIG.
4-6 is removed and a new latch circuit 9-9.9-10 is installed.
Expansion ROM 13-2.13-3 and ROM 13-
ADD 14-2 is provided for the address input of 3, and M P
The outputs of the latch circuits 9-7 to 9-10 are divided into MPXs.

Next, Table 2 shows ROM 13-1 rask conversion in enlargement mode.

(Left below) In Table 2, the output address of CRTC3 is 0 to 2 m.
n 1 + output raster is 0xy-1, but RO
Due to M13, the address in horizontal expansion mode is 0 to m-1
,2m~3m-1...2m(n-1)~(2n-1)
The same address as m-1 is output twice in a row, and the raster is 0.
-y-1 (Fig. 3(d)).

Also, the addresses in vertical enlargement mode are 0 to (n-1)m-
1, and the raster outputs the same raster twice in succession as O, O, . . . , y-1 (FIG. 3(c)). And in vertical and horizontal expansion mode, the address is 0, O, ~, m-1.2m, 2
m, ~,3m-1,...,(2n-2)m,(2
m-2) m.

..., the same address as (2n-1)m-1 is output twice in succession, and the raster is also 0, 0, . ~． The same raster as y-1 is output twice (FIG. 3(e)).

Next, FIG. 4 shows the displayed character pattern when enlarged. In this case, one character of CG4-1 has 20 dots horizontally and 24 dots vertically, and the monitor has 640 dots horizontally and 480 dots vertically.

Table 3 above shows the output of the ROM 13-1 in standard, horizontal enlargement, vertical enlargement, and double angle (vertical and horizontal enlargement) modes. In this case, the tank will have 640÷20=32 characters, and the length will have 480÷24=20 lines. That is, the number of displayed characters is 32×20=640 characters. Therefore address M
A is 0-639. The raster is 0 to 23. Also, if the hidden area is 5 characters, the character for one line by CRTC3 is 3
With 9 characters, the display area becomes 32 characters.

Among these, the display area becomes 1'' in the display area, and characters can be displayed on the CRT 6.

The output of the CRTC 3 is converted into standard, horizontally enlarged, vertically enlarged, and vertically and horizontally enlarged (double angle) by the ROM 13-1. Among the outputs of the ROM 13-1, the CG on signal becomes "0" when spaced, making the CG4-1, 4-2 full output "0". The input of ROM 13-1 is MA, raster, and F/
There are vertical and horizontal enlargement signals from F12. This F/F
From 1.12 onwards, address and double-angle mode signals 1. O is output. M P X 13 is in expansion mode (horizontal expansion and vertical expansion >
The ADD 14-1 side to which the address data of No. 2 has been added is selected, and RM2 is accessed from the MPX 10-1. RM2 outputs the character code of the given address. CG4-1.4-2 outputs a character pattern from this code and the raster address of ROM13-1.

On the other hand, CG4-2 is ADD 14-2 when horizontally expanded.
Outputs a character pattern with the raster shifted by one line.

Then, CG4-1, 4-2 outputs the horizontal expansion signal as "0" through the latch circuit, that is, in response to the CRTC clock "O" and "1" during standard and vertical expansion.
To separate G and ROM, ROM data is output when horizontal expansion is "1". Here, the ROM and CG have a 16-bit pattern width, but are outputted as a 20-bit pattern by the MPX10-2 as shown in FIG. The details are shown in Table 4 below.

(Left below) Next, Table 3 shows the data expansion format of ROM 13-2.13-2. Further, the output font in this case is shown in FIG. In this way, double-width characters with different character fonts can be displayed simply by changing the input to the ROM.

Therefore, the display control means of this embodiment works to sequentially read the character codes written in the refresh memory and sequentially supply them to a plurality of character generators, and the standard character generator switches the character pattern corresponding to the input character code. The standard character generator, on the other hand, also outputs character patterns to a plurality of expansion ROMs.

This enlargement ROM outputs character patterns to the multiplexer during horizontal and vertical enlargement. Furthermore, this ROM can convert the character pattern of the standard character generator into a plurality of character patterns and display them in an enlarged manner. The switching means operates to control the display control means by sequentially selecting the output of the standard character generator or the output of the enlargement ROM and outputting character patterns continuously to the display means.
On the other hand, the conversion means outputs the character address and rask address of the display control means as they are in the case of standard character display, and converts and outputs the character address and rask address in the case of enlarged character display. Therefore, it is possible to instantly rewrite and enlarge the screen without using bitmap memory.

Furthermore, the display area specifying means enables enlargement of a desired area by simply specifying a specific address on the display screen, for example, the minimum address, so scrolling during enlargement can be easily performed.

(Effects of the Invention) As described in detail above, according to the present invention, it is possible to enlarge and display characters using a character generator without using bitmap memory, and to rewrite characters, the character code is rewritten in refresh memory. That's all you need. Furthermore, enlargement mode can be enabled using a signal, and scrolling can be done by simply specifying the minimum address on the display screen. Furthermore, it is now possible to enlarge vertically, horizontally, and vertically and horizontally, allowing you to instantly rewrite the screen, enlarge, and scroll when enlarging.

Furthermore, the central processing unit (cPU) controls the entire device.
), as well as eliminating the need for bitmap memory and allowing enlarged display using only standard CG, the device cost can be reduced, and when enlarging horizontally and vertically, the shape of the characters can be changed using an enlargement ROM. Therefore, it is particularly effectively applied to a character display device that uses an enlarged display screen.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a character display device according to an embodiment of the present invention, and FIG. 2(a) shows the M P
Figure 2 (b) is a diagram showing the relationship between the input and output of -2.
Block diagram showing the configuration of the conversion circuit of X10-2, 3rd
The figure shows standard character addresses, CRTC addresses, and various enlarged character addresses. Figure 4 shows an example of CG output pattern and display pattern. Figure 5 shows an explanation of scrolling during enlarged display. Figure 6 7 is a block diagram showing the configuration of a character display device previously proposed by the applicant, FIG. 8 is a timing diagram of the device in FIG. 7, and FIG. 9 is a block diagram showing the configuration of a conventional character display device. Figure 7 is an explanatory diagram of the operation of the device; Figure 10 is an explanatory diagram of the conditions for standard characters and enlarged characters of the equipment in Figure 7;
FIG. 1 is a diagram showing the standard character address, CRTC address, and expanded character address of the device shown in FIG. 7, and FIG. 12 is an explanatory diagram of the CG access method. 1...Central processing unit (CPU), 2...Refresh memory (RM), 3...CRT
Controller (cRTC), 4-1 to 4-6... Character generator, 5... Parallel-serial conversion circuit (PS), 6... CRT
. 7... Oscillation circuit, 8... Bit map memory (BMM), 9-1 to 9
-10...Latch circuit, lo-1~10-3...φ multiplexer (MPX), 11...Pass buffer, 12...Flip-flop (F/F), 13-1~1
3-3...Read-only memory (ROM) 14-1.14-2... Adder (ADD).

Claims (1)

[Claims] (a) a refresh memory that stores character codes; (b) a plurality of character generators that generate standard character patterns corresponding to the character codes; and (c) an enlarged output signal of the character generator. (d) a switching means for switching the output of the character pattern; (e) a display means for displaying the character pattern on a display screen; and (f) a character code read from the refresh memory. display control means for causing the switching means to switch between standard and enlarged character patterns obtained by sequentially supplying the character patterns to each character generator to display them on the display means; and (g) depending on whether the standard characters or enlarged characters are displayed. (h) by specifying a specific address on the display screen;
(i) a display area specifying means for specifying an area to be displayed during enlarged display; (i) a raster changing means for specifying the next raster after the display raster in the vertical and horizontal enlargement mode, and specifying the display raster in modes other than the vertical and horizontal enlargement mode; , (j) converting means for changing an output pattern by switching to an input signal in vertical and horizontal enlargement mode;