JPH044594B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a character display device.

[Prior Art] Because the number of characters in one line in the horizontal direction of a display screen of a CRT, which constitutes a character display device, is too large, it may not be possible to display all the characters at the same time.
In this case, there is a method of sequentially displaying characters that cannot be displayed simultaneously on one screen by changing the display content on the display screen character by character. This display method is called character-by-character scrolling.

[Problem to be solved by the invention] However, when this scrolling is performed continuously,
Since it is difficult to identify the display screen during scrolling, there is a drawback in that it is difficult to scroll to a display screen that includes characters desired to be displayed.

In addition, as a solution to the above-mentioned drawbacks, as in Japanese Patent Application Laid-Open No. 53-35330, only the horizontal synchronizing signal for display is controlled, and the entire display screen of the display device is used to display characters, etc. 1 with pattern
Some devices have achieved smooth scrolling by scrolling in dot units, but in such devices, the entire display screen is scrolled, so the screen area on the opposite side of the moving direction becomes an area where nothing is displayed. This results in the creation of a wasted screen area where nothing can be displayed, and also has the disadvantage that continuous smooth scrolling using the entire display screen cannot be achieved.

In view of the above-mentioned points, an object of the present invention is to provide a character display in which only a pattern of displayed characters, etc. can be horizontally scrolled dot by dot without moving the front part of the display screen, that is, can be smoothly scrolled. The goal is to provide equipment.

[Means for Solving the Problems] In order to solve such objects, the present invention has the following features:
A pattern storage means for storing a pattern of a dot configuration, a display means for displaying the pattern, and a dot signal output means for outputting a dot signal at a predetermined cycle in order to read out the dots forming the pattern to be displayed by the display means. a display control means for reading a pattern stored in the pattern storage means and displaying it on the display means in response to a dot signal from the dot signal output means; and a display control means for reading out a pattern stored in the pattern storage means and displaying the pattern on the display means; a horizontal synchronization signal for synchronizing the display screen of the display means in the horizontal direction in response to an instruction from the instruction means, and a display period signal representing a display period. is controlled in units of one dot in accordance with the timing of the dot signal output from the dot signal output means,
Scroll display control means for scrolling and displaying the pattern displayed on the display screen of the display means horizontally in units of one dot.

[Function] According to the present invention, there is provided a character display device capable of horizontally scrolling only the pattern of displayed characters or the like in units of dots, that is, smoothly scrolling, without moving the front part of the display screen. can do.

The present invention will be explained in detail below based on the drawings.

FIG. 1 shows an embodiment of the present invention. Here, the keyboard 1 as an external device is equipped with keys for sending character symbol signals 5D and scroll signal data 5S for scrolling the screen left and right to the keyboard controller 3. The keyboard controller 3 encodes the signal 5D input from the keyboard 1 and sends it to the CRT control section 7 as an input data signal 9. Further, a scroll signal 11 is sent to the count controller 13 in response to scroll signal data 5S generated by operating a scroll key provided on the keyboard 1. The dot counter 19 divides the frequency of the reference signal 17 generated from the oscillator 15 to generate a character clock signal 21, which is output to the CRT.
It is supplied to the control section 7 as a reference clock signal. Furthermore, the oscillator 15 generates a dot signal 22 having a period corresponding to the dots forming the characters to be displayed. The CRT control unit 7 creates synchronization signals 25 and 27 necessary for display on the CRT 23 and sends them to the video controller 29 and the synchronization signal controller 31. It also outputs a data signal 32D, a refresh signal 32R, an address signal, etc. corresponding to the input data signal 9 input from the keyboard controller 3 to the refresh memory 33 in synchronization with the synchronization signals 25 and 27. The count controller 13 checks whether there is a scroll signal 11 from the keyboard controller 3 every time the vertical synchronization signal 25 from the CRT control unit 7 is synchronized, and if there is a scroll signal 11, the count controller 13 performs the scrolling every cycle of the vertical synchronization signal 25. signal 11
is output to the counter 37 as a selection scroll signal 35. The characters to be displayed on the CRT23 are
As shown in the figure, it has a dot matrix structure with A columns and B rows. The counter 37 is composed of an A-adic counter, and is a reversible counter that performs addition and subtraction by scrolling leftward and rightward. In this case, the number of scroll signals 35 from the count controller 13 is counted, a signal 39 representing the counting state is sent to the synchronous signal controller 31, and the display is rewritten to display a signal 41U representing a carry or a signal 41D representing a carry down. Controller 43
send to Further, the carry signal 41U or the carry down signal 41D is output only during one cycle of the vertical synchronization signal 25 which is output from the CRT control unit 7, and is not carried up or down during the next synchronization of the vertical synchronization signal 25. Return to state. When the count signal 39 from the counter 37 indicates a state of 1 to (A-1), the display rewriting controller 43 does not send the horizontal scroll signal 45 to the CRT control section 7. When there is a carry signal 41U or a carry down signal 41D from the counter 37, the display rewriting controller 43 supplies a horizontal scroll signal 45 to the CRT control section 7.

The refresh memory 33 stores the data signal 32D sent from the CRT control section 7 to be displayed on the screen at the corresponding address. The read data signal 53 of this refresh memory 33 is sent to the character generator 5.
Send to 5. As shown in FIG. 3, the refresh memory 33 stores the contents of one column more than the number of columns on the display screen, that is, the contents up to the column next to the character column at the right end of the display screen. The character generator 55 is
A parallel signal 57 representing a corresponding information pattern is generated from the code of the data signal 53 sent from the refresh memory 33 in parallel and series (hereinafter referred to as P/S).
It is sent to converter 59. Synchronous signal controller 31
, the horizontal synchronization signal 27 and the display period signal 61 from the CRT control unit 7 are delayed by the number of counting states represented by the signal 39 from the counter 37 in units of dots of the dot signal 22, and the delayed horizontal synchronization signal 27 and the display period signal 61 are respectively delayed. Signal 27D and display period signal 61
D is supplied to the video controller 29. This video controller 29 receives both signals 27D and 61D from the synchronization signal controller 31, a video signal 67 from the P/S converter 59, and the CRT control section 7.
The vertical synchronizing signal 25 from the CRT 23 is sent to the CRT 23. The CRT 23 displays characters based on data input through the keyboard 1.

Next, smooth scrolling will be explained. FIGS. 4A to 4F show timings when horizontal smooth scrolling is not performed. In this case, the horizontal synchronization signal 27 and the display period signal 61 from the CRT control unit 7 do not change (delay), and the signal 27
D and signal 61D. The video signal 67 is
The dot signal {1} at the beginning of the first character is displayed. In this case, the outputs of the count signal of the counter 37, the carry signal 41U, and the carry down signal 41D are both zero. FIGS. 5A to 5F show the case of one-dot scrolling to the left. In this case, from the state shown in FIG. 4, the scroll signal 11 is output by operating the keyboard 1, and the count in the count signal 39 from the counter 37 becomes 1. As a result, the synchronization signal controller 31 controls the CRT.
The horizontal synchronization signal 27 and display period signal 61 from the control section 7 are delayed by one dot in accordance with the timing of the dot signal 22 from the oscillator 15, and the delayed horizontal synchronization signal 27D and display period signal 61D are output. Further, since the carry signal 41U or the carry down signal 41D is not sent from the counter 37, the horizontal scroll signal 45 from the display rewriting controller 43 is not output to the CRT control section 7. The vertical synchronizing signal 25 and video signal 67 from the CRT control section 7 are the same as in the case of FIG.
As shown in Figure 3, the refresh memory 33 has an extra data storage area for one character string than the display screen, so the output to the CRT 23 is for the characters displayed at the left end of the screen in Figure 4. 1 on the left side of
The row of dots is no longer displayed, and conversely, in the state shown in FIG. 4, the row of one dot at the left end of the character next to the character displayed at the right end of the screen is displayed. As a result, the display starts from {2} as shown in FIG. 5F. As you will see, it becomes possible to shift the display on the CRT 23 one dot to the left. By repeating the same steps, it becomes possible to scroll to the left by (A-1) dots. Next, let's look at the case of scrolling by A dot. As shown in FIG. 5, the above operation is repeated for the 1st to (A-1) dots, and for the A dot, as shown in FIG.
A horizontal scroll signal 45 is sent to the CRT control unit 7, and a refresh signal 32R is generated thereby.
is sent to the refresh memory 33, and the memory 3
The contents of 3 change by one character string from FIG. 3 to FIG. 6. As a result, as shown in FIG. 7, the horizontal synchronization signal 27 and the display period signal 61 are
Since the counter signal 39 from 7 is 0, it is possible to scroll to the left by A dots. Scrolling of more dots can be done in the same way.

Next, scrolling in the right direction will be described.
FIG. 8 shows the case of scrolling one dot to the right from the state of FIG. 4. In this case, the counter 37 performs subtraction counting in response to the scroll signal 11 generated by the operation of the keyboard 1, and a downshift signal 41D and a count signal 39 indicating the counting state (A-1) are output. In response to this downgrade signal 41D, a horizontal scroll signal 45 is sent from the display rewrite controller 43 to the CRT control unit 7, and in response to the refresh signal 32R, the contents of the refresh memory 33 are changed from FIG. 3 to FIG. Rewrite it as Further, a signal 39 indicating the counting state (A-1) is sent from the counter 37 to the synchronization signal controller 31, and as shown in FIG. -1) Horizontal synchronization signal 27D and display period signal 61 delayed by a dot, respectively.
D is output. Since the vertical synchronization signal 25 and video signal 67 do not change, the left edge of the display screen (A
-1) The next row of dots is displayed instead of being displayed. Therefore, the display will be scrolled one dot to the right compared to the state shown in FIG. 3, and will be displayed starting from {A''}. When scrolling by 2 to A dots, the downshift signal 41D will not be output.2 In dot scrolling, the horizontal synchronizing signal 27 and display period signal 61 are delayed by (A-2) dots.
By repeating the same process up to the A dot, when scrolling to the A dot as shown in FIG. 10, the horizontal synchronization signal 27 and display period signal 61 are input to the video controller 29 without changing. This allows scrolling to the right by A dots. The same thing can be said for scrolling to the right beyond the A dot. Also, if you scroll to the left (right) before scrolling one character to the right (left), the counter 3
7 adds and subtracts the horizontal scroll signal 45, and outputs the horizontal refresh signal to the CRT only when the carry signal 41U or the carry down signal 41D is generated.
Since the control unit 7 outputs the output, smooth scrolling is possible even in such a case.

As mentioned above, although one embodiment in FIG. 1 has been described, it is also possible to realize two addition counters for rightward and leftward scrolling.
It goes without saying that it is also possible to add a data storage area for one character string to the refresh memory 33 on the opposite side of FIG. 3.

By counting the scroll signals in this way and changing the horizontal synchronization signal and display period signal in dot units, only the patterns such as characters displayed on the screen can be smoothly scrolled without moving the entire display screen. can be realized. Furthermore, if the keyboard has another character-based scroll signal key, it is possible to use dot-based smooth scrolling and character-based scrolling together. Furthermore, by changing the synchronization signal in units of two dots or more, it is also possible to scroll in the horizontal direction in units of two dots or more.

[Effects of the Invention] As detailed above, according to the present invention, only the pattern of displayed characters, etc. can be horizontally scrolled dot by dot without moving the front part of the display screen, that is, can be smoothly scrolled. Therefore, it is possible to realize a character display device that eliminates the conventional drawbacks caused by this.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of a character display device according to the present invention, FIG. 2 is a line diagram showing an example of the dot structure of characters, and FIGS. 3, 6, and 9 are diagrams showing a refresh memory. Diagram showing the contents, Figure 4A
~F, Figure 5 A~F, Figure 7 A~F, Figure 8 A~
F and FIGS. 10A to 10F are signal waveform diagrams showing timing for explaining scrolling in the apparatus of the present invention. 1...Keyboard, 7...CRT control unit, 25,
27...Synchronization signal, 33...Refresh memory, 37...Counter, 41...Display rewriting controller, 55...Character generator, 59...Serial-parallel converter.

Claims (1)

[Scope of Claims] 1. A pattern storage means for storing a pattern of dot configuration, a display means for displaying the pattern, and a dot signal at a predetermined period in order to read out the dots constituting the pattern to be displayed by the display means. a dot signal output means for outputting a dot signal; a display control means for reading a pattern stored in the pattern storage means and displaying it on the display means in response to the dot signal from the dot signal output means; an instruction means for instructing horizontal scrolling of the pattern displayed on a display screen; a horizontal synchronization signal for horizontally synchronizing the display screen of the display means in response to an instruction from the instruction means; The display period signal representing the display period is controlled in units of one dot in accordance with the timing of the dot signal output from the dot signal output means, so that the pattern displayed on the display screen of the display means is controlled horizontally by one dot. 1. A character display device comprising scroll display control means for scrolling display in units.