JPH04199088A - Led dot matrix display device and its control method - 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 (Industrial Application Field) The present invention is directed to LED dotma!・Regarding risk display devices,
In particular, the screen R using the shift register of the screen controller
The present invention relates to an LED dot matrix display device capable of controlling AM (V-RAM) and a control method thereof.

(Prior art) Regarding the conventional ED tosomatrix display device, the first
This will be explained using the circuit configuration block diagram shown in FIG.

The CPUI specifies the device to be accessed via the address bus, for example, accesses data in a storage device (not shown), and further specifies the address of the multiplexer (MPX) 3 using the address bus. Open the bus driver 4 and transfer data from the storage device etc. to the screen RA.
Write to M (V-RAM)7.

The MPX3 is a switch between the CPUI and the screen controller 2. When operating the CPUI or the V-RAM 7, the path driver 4 is open and image data is written to the V-RAM 7, and the screen controller 2 is switched to the V-RAM 7. -RA
When operating M7, the path driver 4 is closed, and at this time, the PvI P
It is designed to connect AM7.

The dots oscillated from the oscillator 5 are multiplied by 1/8 (frequency divided by 8) by the transmission frequency divider 10, then one is output to the parallel/serial converter (P/S converter) 8, and the other is output to the parallel/serial converter (P/S converter) 8. The image is then converted into a 1/8x dot and output to the screen controller 2.

The screen controller 2 outputs a display address to the V-RAM 7 via MP'X3 according to the timing of the input dots.

The V-RAM 7 receives a display address corresponding to the content to be displayed on the LED display unit 9 from the screen controller 2 through the MPX 3, and transmits the data corresponding to the display address to the output timing of the frequency divider 10 for transmission. S converter 8
The signal is output to the LED display section 9 for display.

In the conventional LED dot matrix display device, as shown in FIG. 11, the V-RAM V has about one or two planes with the same capacity as the LED display section 9.
The displayed content was retained in the Todd image. Then, to scroll the displayed content, add V
-While writing to the RAM 7, the display screen of the LED display section 7 is transferred to the bank by operating the created planes from the CPU to the V-RAM 7 via the screen controller 2, like sending frames of a movie. By switching, the content displayed on the LED display section 7 was made to appear to be scrolling.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional LED dot matrix display device, even while the LED display unit 7 is displaying planes, the CPU 1 is always running in order to prepare the next plane to be switched. Since it is necessary to write a plane in the V-RAM 7, most of the work performed by the CPU 1 within a certain period of time is occupied by plane creation, and the display screen of the LED display section 9 is long. However, if the display screen is large, there is a problem that the plane creation process by the CPU may not be able to keep up with the screen switching process.

In addition, since the plane that has finished displaying - degrees has the property of being rewritten immediately, if you try to display it repeatedly, you have to rewrite the plane again, and there is a problem that it is not possible to display it repeatedly. Ta.

The present invention has been made in view of the above-mentioned circumstances.
An object of the present invention is to provide an LED dot matrix display device and a control method thereof, which can reduce the processing time of a CPU that performs control and easily perform scrolling operations.

(Means for Solving the Problems) The invention according to claim 1 for solving the problems of the conventional example is an LED dot matrix display device in which image data is written in a width corresponding to the display width of the display screen. a display section for displaying the image data in the screen RAM; a screen controller having a register into which an address of the image data on the screen RAM is written; and a CPU for giving an address to the register of the screen controller. The present invention is characterized in that a window corresponding to the display screen is set on the screen RAM by writing an address given from the CPU into a register of the screen controller.

The invention set forth in claim 2 for solving the above-mentioned problems of the prior art is, in the LEDF matrix display device set forth in claim 1, by rewriting the register in the screen controller according to an address instruction from the CPU and setting the register on the screen RAM. It is characterized by moving the window setting position and scrolling the display screen on the display unit.

(Function) According to the invention described in claim 1, there is a screen RAM in which contents to be displayed are written in advance, a display section that displays the contents of the screen RAM, and a window that is the same as the display contents of the display section on the screen RAM. Since the LED dot matrix display device has a screen controller that controls settings and a CPU that instructs the screen controller to address on the screen RAM, the CPU is not required to scroll the display screen of the display unit.
The display screen on the display unit can be scrolled by controlling the screen controller and operating the window on the screen RAM based on the address instruction from the screen RAM, so there is no need to rewrite the planes of the screen RAM one after another, and the load on the CPU can be reduced. .

According to the invention as claimed in claim 2, there is provided an LED dot matrix display device that scrolls the display screen by operating a window provided under the control of a screen controller on a screen RAM in which contents to be displayed are written in advance under the control of a screen controller. Since this control method is adopted, there is no need to sequentially rewrite the planes of the screen RAM to scroll the display screen of the display unit of the LED dot matrix display device, and the load on the CPU can be reduced.

(Example) An example of the present invention will be described with reference to the drawings.

FIG. 1 is a circuit configuration block diagram of an LED dot matrix display device according to an embodiment of the present invention. Furthermore, the 10th
Portions having the same configuration as those in the figures will be described with the same reference numerals.

The configuration of the LED dot matrix display device of this example is as follows:
A CPU that performs control processing for each component, a screen controller 2 that generates timing signals necessary for display, and a screen RAJ4 (V-R
AM) 7', an LED dot matrix display section 9, an LED control section 11 that realizes a scroll function, and other parts.

Each component will be specifically explained below.

A screen controller 2, a multiplexer (MPX) 3, a bus driver 4, and an LED control unit 11 are connected to the address hash and data hash from the CPU.
The UI specifies each component to be accessed via the address bus, writes image data to the V-RAM 7' via the data bus, and writes V-RAM to the screen controller 2.
Give the display start address in RAM 7', or
It provides initial setting data to the ED control section 11.

The screen controller 2 uses, for example, a CRTC (CRT controller), which originally controls the display of a CRT display, and generates various timing signals necessary for CRT display according to values set by the CPUI. It is a controller. - In the boat fishing, the screen controller 2 is provided with a register, and there is a function to scroll the inside of the V-RAM 7' vertically and horizontally by simply writing a value to this register from the CPUI. This is the basic principle of windows.

The MPX3 is a switch between the CPUI and the screen controller 2, and when the CPU operates on the V-RAM 7', the bus driver 4 is opened and image data is written to the V-RAM 7', and at this time the MPX3 The screen controller 2 and V-RAM 7' are not connected, and when the screen controller 2 or V-RAM 7' is operated, the bus driver 4 is closed, and at this time the MPX3
is designed to connect the screen controller 2 and the V-RAM 7'.

A constant dot clock is oscillated from the oscillator 5, multiplied by 1/8 (divided by 8) by the transmission frequency divider 10, and then one is output to the parallel/serial converter (P/S converter) 8. The other signal is converted into a 1/8 dot by the screen controller (CRTC) frequency divider 6 and output to the screen controller 2. The screen controller 2 outputs the data to the V-RAM via the MPX3 depending on the timing of the input dots.
The display address is output to 7'.

The storage capacity of the V-RAM7' is considerably larger than that of the conventional V-RAM7, and while the conventional V-RAM7 had a capacity of a plate equal to the display screen, this implementation The V-RAM 7' in the example has a capacity that can store a considerable amount of the contents to be scrolled and displayed.

Then, the V-RAM 7' receives a display address corresponding to the content output from the screen controller 2 to the LED dot matrix display unit 9 through the MPX 3.
Data corresponding to the display address is output to the LED dot matrix display section 9 via the P/S converter 8 at the output timing of the transmission frequency divider 10, and is displayed. Furthermore, V-R
Since the content of AM7' is a dot image, no character generator is provided in the circuit of this embodiment.

In the screen controller 2, the LED control unit 11 can realize the horizontal horizontal jump scroll (scrolling in single character units) function by giving a start address shifted by one character unit. Since it does not have a smooth scroll function that crawls while displaying intermediate stages, in order to realize the smooth scroll function, the latch signal that provides the display timing of display data and the display address of the display line are set to LE.
It is designed to be output to the D dot matrix display section 9.

The LED dot matrix display section 9 is formed by a line of 16 x 16 dot light emitting diodes (LED),
Depending on the timing of the address instruction from the screen controller 2, the image data serially converted and outputted from the V-RA~17' by the P/S converter 8 is displayed. Further, the LED dot matrix display section 9 is given a clock from the transmission frequency divider 10, and a latch signal and The address of the display line is given.

The image data is displayed at the display position on the display unit 9 according to the address of the display line, and the latch timing can be varied by giving the latch timing (latch timing) from the CPUI using a set value to determine which dot to latch. By doing this, we are trying to achieve horizontal smooth scrolling.

The control operation of the LED dot matrix display device of this embodiment will be explained below.

The essential difference between the conventional control method and the control method of this embodiment is that the conventional control method changes by sequentially rewriting planes whose contents are shifted little by little within the display area of a fixed display section, so that the screen appears as if it were a screen. In contrast, in this example, V-RAM 7 is fixed.
' The content to be displayed is written in advance and the window moves over the fixed display content, making it appear as if the screen is scrolling.

Specifically, this will be explained using the conceptual diagram of the initial settings of the screen controller shown in FIG.

FIG. 2 shows a conceptual diagram when the screen controller 2 initializes the V-RAM 7' and the window. First, the V-RAM 7' is set to have a horizontal display memory width of M characters, and the display window is set to display one line to be the same width as the LED dot matrix display section 9.

Here, by setting the end address and the start address to be a series of continuous ring RAMs using an offset value, if necessary, it is also possible to create an infinite scroll screen.

The vertical and horizontal scrolling will be explained using the conceptual diagrams showing the vertical and horizontal scroll states in the V-RAM 7' of FIGS. 2 and 3.

Up and down scrolling uses a start address register that specifies the display start address inside the screen controller 2, and a vertical smooth scroll register that instructs to display intermediate stages of displayed characters in order to achieve vertical smooth scrolling in up and down scrolling. This can be done by rewriting.

In other words, by writing the start address of the displayed character from the CPU to the start address register of the screen controller 2, the LE
A window having the same width as the character string displayed on the display screen of the D dot matrix display section 9 is set, and the characters within the window are displayed on the LED dot matrix display section 9. Furthermore, by writing the start address of the next display character into the start address register from the CPU, the window moves vertically and the characters jump and scroll vertically.

In addition, the displayed characters are to be displayed in 16 rasks in the vertical direction, and the number of rasters to be displayed can be determined by writing the number of rasters to the vertical smooth scroll register of the screen controller 2 from the CPUI. It is possible to display intermediate stages of characters, and by rewriting the number of rasters in the vertical smooth scroll register in the order of 1 to 16 rasters, it is possible to scroll smoothly in the vertical direction.

Regarding horizontal scrolling, while horizontal jump scrolling is performed using the start address register inside the screen controller 2, the horizontal smooth scroll register provided within the LED control section 11 is also rewritten to perform scrolling.

That is, by writing the start address of display characters from the CPU into the start address register of the screen controller 2, a window is set on the V-RAM 7', the characters in the window are displayed on the LED dot matrix display section 9, and further, By writing the start address of the next display character into the start address register from the CPU 1, the window moves horizontally and the characters jump and scroll horizontally.

In addition, each displayed character is to be displayed as 16 dots in the horizontal direction, and the number of dots to be displayed up to the final character to be displayed is determined by the horizontal smoothing in the LED control unit 11. By writing to the scroll register from the CPU, you can display the middle stage of the displayed character, and set the number of dots to 1 in the horizontal smooth scroll register.
By rewriting in the order of ~16 dots, it is possible to scroll smoothly in the horizontal direction.

The horizontal smooth scroll register provided in the LED control unit 11 is specifically composed of a fixed number of dots counter and a variable number of dots counter. - Make initial settings so that more characters can be displayed, use a fixed number of dots counter to count the number of dots up to the M character, and then use a variable number of dots counter with the end number of dots set to display M+.
The number of dots in one character to be displayed is counted by the number of clocks, and a latch signal is output to the LED dot matrix display section 9 when the count is completed.

The LED dot matrix display unit 9 that receives the latch signal displays on the display screen up to the number of dots corresponding to the M+1 character at the time of latching. However, the first half of the first character M appears to be pushed out of the display screen and is not displayed on the screen.

In this way, smooth scrolling in the horizontal direction can be realized by rewriting the set number of dots on the variable number of dots counter in the order of 1 to 16 dots.

Further, in the LED dot matrix display device of this embodiment, the display characters are displayed in one line on the LED dot matrix display section 9 using the screen controller 2, and therefore the window settings are also based on one line of characters. In other words, the number of vertically displayed characters in the internal register of the screen controller 2 is set to one.

In this way, in the LED dot matrix display device of this embodiment, the number of vertically displayed characters is set to 1, because if it is other than 1, when a double-height character is displayed, it exceeds the total number of horizontal characters in the internal register of the screen controller 2. This is because there is a problem that the display may extend to the next line or may not be displayed correctly.

Regarding the above problems and their countermeasures, using Figures 4 to 7,
The total number of horizontal characters in the internal register of screen controller 2 is set to 1.
This will be explained using a simple example using 0 characters.

The case where the number of vertically displayed characters in this embodiment is 1 will be explained using FIG. 4.

FIGS. 4(a) to 4(C) are horizontal scroll views of one line display when normal half-width characters are displayed. Fig. 4(a) shows the initial drawing, Fig. 4(b) shows the drawing when the window has moved horizontally, and Fig. 4(c) shows the drawing when actually viewed on the display screen. . In this embodiment, the frame displaying loXIO indicates the conceptual range of V-RAM 7', and the large frame is a window set according to instructions from the screen controller 2, with 1 line of 10 characters set. Now I can scroll horizontally without any problems.

In addition, Figures 5(a, ) to (c) are horizontal scroll diagrams of multiple line display when displaying normal half-width characters.
5(a) is an initial view, FIG. 5(b) is a view with the window moved horizontally, and FIG. 5(c) is a view when actually viewed on the screen of the display unit. In the example shown in FIG. 5, the window is set to have 10 characters and 4 lines, and in this case as well, horizontal scrolling is possible without any problems.

Further, FIGS. 6(a) to 6(c) are horizontal scroll diagrams of a multi-line display when displaying double-width and vertical-width characters. In the case of FIG. 6, the window is set to have 10 characters and 4 lines, and is designed to display double-height and double-width characters. If the characters are double-width in height and width, if the character exceeds the total number of horizontal characters and moves to the next line, the display will not be displayed correctly, as shown in FIG. 6(c).

FIG. 7 is an explanatory diagram for realizing horizontal scrolling of a one-line display when displaying double-width and vertical-width characters.

In the case of FIG. 7, the window is set to 10 characters per line, and this is also an example of a case where the total number of horizontal characters is exceeded, and scrolling is possible without any problem.

This is the V-RAM 7'a dedicated to the first line of the LED dot matrix display section and the two of the LED dot matrix display section.
The display data for the upper half and lower half when vertically doubled are respectively set in V-RAM7'b dedicated to the row, and the window is set to 10 in each of V-RAM7'a and V-RAM7'b. Since the method is to display characters in one line and then combine them again, even if the window is set to 10 characters in one line and exceeds the total number of horizontal characters, it can be displayed, and scrolling up, down, left, and right according to address instructions is possible. It becomes possible.

As described above, it can be said that it is difficult to correctly display scrolling when double-height characters exceed the total number of horizontal characters.

In addition, a CRT uses thermoelectrons fired by an electron gun and hits a phosphor to emit light, and an image is displayed on a CRT display screen. A CRT usually has about 500 rasters.
The LED light-emitting chips that make up the LED dot matrix panel have no afterglow at all, perhaps because the phosphor has a characteristic of remaining glow even after being excited by electrons, which is why it can be recognized by the human eye as an elephant. Therefore, a normal LED panel has 16 rasters per line, 32 rasters for 2 lines, and 6 rasters for 4 lines.
4 rasks, and if a single screen controller is used to display such a plurality of lines, unlike a CRT, the brightness will inevitably decrease.

For the above reasons, it is preferable that the display panel of the LED dot matrix display section driven by the screen controller has one line.

From the above explanation, using the function of the screen controller 2, the window settings of the LED dot matrix display section 9 on the V-RAM 7' under its control can be set in one line in a size corresponding to the LED dot matrix display section. shall be carried out.

According to this embodiment, the window with the display width corresponding to the panel of the LED dot matrix display section 9 or the V-RAM 7'
By moving the upper part according to the address instruction from the screen controller 2, the display appears to scroll. This is done using the scroll function of 2. This reduces the number of times the CPU 1 goes to write the display data in the V-RAM 7'+: once, which frees up CPU processing time, and allows you to write long display lines or multiple lines. It has the effect of being able to display objects and two-color LED displays without any problems, and even when the -degree display has finished, due to the structure of the ■-RAM7',
It also has the effect of being able to be played back instantly.

Further, as mentioned above, as another embodiment, a configuration example of an LED dot matrix display device in which the number of display lines is two will be described using the circuit configuration block diagram of FIG. 8.

The basic operation of this other embodiment is the same as that described in this embodiment, or the difference in configuration is that two display lines are
LED dot matrix display sections 9a and 9b for each row separately
The LED dot matrix display section 9a that displays the first line and the LED dot matrix display section 9b that displays the second line are combined to perform a composite display.

In this way, one screen controller 2 per line display.
is used because if one screen controller 2 were to control the display of multiple lines, the duty would change and the brightness of the LED display would decrease.
This is to prevent this.

Furthermore, as another example, when the display colors are two colors, L
An example of the configuration of an ED dot matrix display device will be described using the circuit configuration block diagram of FIG. 9.

The basic operation of this other embodiment is the same as that described in this embodiment, but the difference in configuration is that two VVs are used for each color.
-RAM7'e and 7'f are provided, and access to V-RAM7'e and 7'f is performed independently from the CPUI, and two V-RAMs are accessed from the screen controller 2.
Retrieval to 7'e and 7'f is performed simultaneously to realize two-color LED display.

(Effects of the Invention) According to the invention described in claim 1, there is provided a screen RAM in which content to be displayed is written in advance, a display unit that displays the content of the screen RAM, and a display unit that displays the display content of the display unit on the screen RAM. A screen controller that controls the settings of the same window, and a CP that instructs the screen controller to the address on the screen RAM.
Since it is an LED dot matrix display device having U, it takes C to scroll the display screen of the display unit.
The screen controller can be controlled by address instructions from the PU to operate the window on the screen RAM and scroll the display screen on the display unit, so the screen RA
There is no need to rewrite the plane of M sequentially, and CP
This has the effect of reducing the load on U.

According to the invention as claimed in claim 2, there is provided an LED dot matrix display device that scrolls the display screen by operating a window provided under the control of a screen controller on a screen RAM in which contents to be displayed are written in advance under the control of a screen controller. Since this control method is adopted, there is no need to sequentially rewrite the planes of the screen RAM to scroll the display screen of the display section of the LED dot matrix display device, which has the effect of reducing the load on the CPU.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration block diagram of an LED dot matrix display device according to an embodiment of the present invention, FIG. 2 is a conceptual diagram of initial settings of a screen controller, and FIG. 3 is a conceptual diagram showing vertical and horizontal scrolling states. Figures 4 (a) to (c) are horizontal scroll diagrams of single-line display when displaying normal half-width characters, and Figures 5 (a) to (C) are multi-line diagrams when displaying normal half-width characters. Horizontal scroll diagram of display, Figures 6 (a) to (C) are horizontal scroll diagrams of multi-line display when displaying double-height characters;
FIG. 7 is an explanatory diagram for realizing horizontal scrolling of a single line display when displaying double-height characters, and FIG. 8 is another example 2.
LED for row display. Circuit configuration block diagram of dot matrix display device, FIG. 9 shows LED for two-color display of another embodiment.
Circuit configuration block diagram of dot matrix display device, 1st
Figure 0 is a circuit configuration block diagram of a conventional LED dot matrix display device, and Figure 11 is a diagram showing the conventional LED display capacity and V-
It is a structural relationship diagram of RAM. 1... CPU 2... Screen controller 3... Multiplexer 4... Bus driver 5... Oscillator 6... Screen controller (CRTC) frequency divider 7...Screen RAM 8...Parallel/serial converter 9...L
ED dot matrix display section 10/transmission frequency divider] 1...LED control section Applicant: Kokusai Denki Co., Ltd. Agent, Patent attorney: Kiyotaka Sakamoto, Agent: Patent attorney, Nobuhiro Funatsu, Figure 2, Figure 4 ( C) E Yorokoko ■■ Natsuguchi Figure 5 Figure 7 A1 7'a) + VI'IO) , 5 Procedural amendment (voluntary) January 18, 1991 Mr. Satoshi Uematsu, Commissioner of the Patent Office, 1, of the case Display 1990 Patent Application No. 331578 2 Title of Invention LED dot matrix display device and control method 3,
Relationship with the case of the person making the amendment Patent applicant (1, 1, 2) Kokusai Denki Co., Ltd. 5. Date of amendment order Month, Day, 2008 (Shipping port) 6. Detailed description of the invention in the specification to be amended " column 7, page 4, line 14 of the statement of contents of the amendment, change "display section 7" to "display section 9."
and correct it. "Display section 7" on page 4, line 15 of the specification is "display section 9"
and correct it. Specification! l! 4l "Display section 7" in the fourth row of the page is corrected to "display section 9." j −

Claims (2)

[Claims] (1) A screen RAM in which image data is written in a width corresponding to the display width of the display screen, a display section that displays the image data in the screen RAM, and a register in which the address of the image data on the screen RAM is written. and a CPU that provides an address to a register of the screen controller, and writes a window corresponding to the display screen on the screen RAM by writing the address given from the CPU to the register of the screen controller. An LED dot matrix display device characterized by performing settings. (2) In the LED dot matrix display device described in item 1, the register in the screen controller is rewritten according to an address instruction from the CPU, the window setting position set on the screen RAM is moved, and the display screen on the display unit is scrolled. A method for controlling an LED dot matrix display device, characterized in that: