JPH04199089A - LED dot matrix display device and its display screen scrolling 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 relates to an LED dot matrix display device and its display screen scrolling method, and in particular to control of screen RAM (V-RAM) using a shift register of a screen controller. The present invention relates to an LED dot matrix display device and its display screen scrolling method, which allows smooth scrolling at the start and stop of scrolling.

(Prior art) Regarding the conventional LED dot matrix display device, the ninth
This will be explained using the circuit configuration block diagram shown in the figure.

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 via the address bus. to open the bus driver 4 and transfer data from the storage device etc. to the screen R.
Write to AM (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 bus driver 4 is open and image data is written to the V-RAM 7, and the screen controller 2 is switched on. V-R
When operating on AM7, bus driver 4 is closed,
2nd time MP X3 has screen controller 2 and V-RAM
7 is connected.

The clock oscillated from the oscillator 5 is transmitted to the transmission frequency divider 10.
Then, one is output to a parallel/serial converter (P/S converter) 8, and the other is converted to a 78 times clock and output to the screen controller 2. The screen controller 2 sends the CPUI to the V-RAM 7 via the MPX 3 according to the timing of the input clock.
Outputs the display address given by .

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

The conventional LED dot matrix display device has a plurality of planes in the V-RAM 7 with the same capacity as the LED dot matrix display section 9, as shown in FIG.
The display content was held as a dot image.

Then, in order to scroll the display contents, the content is written to the V-RAM 7 so that the contents are slightly shifted from the other planes to these multiple planes, and these planes are sent to the CPU like the frames of a movie. By switching the display screen of the LED dot matrix display section 9 by operating from the screen controller 2 to the V-RAM 7, the contents displayed on the LED dot matrix display section 9 appear to be scrolling. Met.

Furthermore, regarding the scrolling state of the display screen scrolling method in the LED dot matrix display device, LE
The operation when the display screen in the D dot matrix display section 9 stops is shown in FIGS. 11 (a) to (g), and the operation when the display screen in the LED dot matrix display section 9 starts is shown in FIGS. 12 (a) to ( g) and will be explained below.

In order to realize scrolling, as shown in the close-up diagram of FIG. By switching the information in detail every unit time using the interrupt operation of the heart timer 12, the image appears to be scrolling.

The method of creating this "unit time" is to start the hard timer 12 and keep the CPU running until the count of the hard timer 12 expires, as shown in the conceptual diagram of scroll processing in FIG.
performs normal processing, and when the count of the hard timer 12 expires, the hard timer 12 outputs CP.
An interrupt occurs in U1, and CP is activated at the timing of the interrupt.
The display start address is transmitted from the UI to the screen controller 2. After that, restart the hard timer 12 again,
Also, normal processing is performed on the CPUI.

By repeating this operation, the hard timer 12
From one interrupt to the next interrupt, the screen on the LED dot matrix display section 9 is displayed at a fixed position, and the display screen changes due to the interrupt operation, indicating whether the screen has moved to the next display position. The time from one interrupt timing to the next interrupt timing can be used as a "unit time", and by using this, the screen can be scrolled by switching the display screen finely for each unit time. It was meant to look like this.

More specifically, a conventional scrolling method using screen switching at regular intervals will be explained using FIG. 14.

It is assumed that all plane (display screen) switching is performed by interrupt operation by the hard timer 12.

By doing so, you can achieve accurate scrolling movements. In the operation shown in FIG. 14, the CPU starts the hard timer 12 before performing normal processing, and enters normal processing. The hard timer 12 counts a specific time (timer count), and when the specific time has finished counting, gives an interrupt operation to the CPU 1.

The CPU, which was performing normal processing, determines that there is an interrupt and notifies the screen controller 2 of the new "display start address."The screen controller 2 gives the start address to the V-RAM7, and from the V-RAM7 Screen data of a new plane is given to the LED dot matrix display section 9 to switch the screen. The CPUI starts up the heart timer co2 again and performs normal processing. Conventional scrolling was performed in this manner.

(Problem to be Solved by the Invention) However, in the conventional LED dot matrix display device, even while displaying one plane on the LED dot matrix display section 9, the next plane to be switched is always prepared. The CPU 1 needs to write a plane in the V-RAM 7, and most of the CPU's work within a certain period of time is occupied by plane creation, and the display on the LED dot matrix display section 9 If the screen is long or the display screen is large, the CPU
There was a problem that the plane creation process by I was not in time for the screen switching process.

In addition, in the conventional scrolling method described above, since the timer count of the hard timer 12 is constant, the 11th
When the scrolling of the display screen in the figure is stopped, the displayed characters scrolling from the right end appear to suddenly stop at the moment when the screen shown in Fig. 11(e) changes to the screen shown in Fig. 11(f), and At the start of the scrolling of the display screen in Figure 12, the displayed characters that had stopped start scrolling to the left and suddenly appear at the moment when the screen shown in Figure 12 (b) changes to the screen shown in Figure 12 (c). It looks like it has started. Therefore, if the displayed characters are scrolling at a constant speed, the human eye is accustomed to the scrolling speed, but when the displayed characters suddenly stop or start, the human eye becomes accustomed to the scrolling speed.
The problem was that the human eye could momentarily not be able to keep up with the scrolling speed of the displayed characters, making it extremely tiring for the eyes of the person looking at the display screen.

The present invention has been made in view of the above-mentioned circumstances.
An LED dot matrix display that can reduce the processing time of the CPU that controls the display, simplify the scrolling operation, and also enable smooth start and stop of display screen scrolling in the LED dot matrix display section. The object of the present invention is to provide a device and its display screen scrolling method.

(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 screen controller having a screen RAM, a display section for displaying image data in the screen RAM, and a register into which an address of the image data on the screen RAM is written;
C giving an address to the register of the screen controller
It has a PU and a timer that gives the output timing of the address outputted from the CPU to the CPU, and writes the address given from the CPU to the register of the screen controller to display it on the display screen on the screen RAM. It is characterized by configuring the corresponding windows.

The invention according to claim 2 for solving the problems of the conventional example rewrites the register in the screen controller according to an address instruction from the CPU in the display screen scrolling method of the LED dot matrix display device according to claim 1. The scrolling speed of the display screen on the display section is controlled by moving a window set on the screen RAM and making variable the timing interval of address output from the timer to the CPU.

The invention according to claim 3 for solving the problem of the conventional example is, in the display screen scrolling method of the LED dot matrix display device according to claim 2, the scrolling speed is gradually increased at the start of screen scrolling. ,
The feature is that the scrolling speed is controlled so that when the screen scrolling stops, the scrolling speed is gradually slowed down and then stopped.

(Function) According to the invention as claimed in claim 1, there is provided a screen RAM in which contents to be displayed are written in advance, and a screen for controlling the setting of the same window as the display contents of the display section of the LED dot matrix display device on the screen RAM. a controller, a CPU that instructs the screen controller to address on the screen RAM;
The LED dot matrix display device includes a timer that gives the timing of address instructions to the CPU, and an LED dot matrix display that controls the screen controller based on the address instructions from the CPU, operates the window on the screen RAM, and scrolls the display screen on the display unit. There is no need to sequentially rewrite the brain of the screen RAM to scroll the display screen of the section, and the load on the CPU can be reduced.

According to the invention set forth in claim 2, in the LED dot matrix display device set forth in claim 1, the window provided under the control of the screen controller on the screen RAM in which contents to be displayed are written in advance is operated according to instructions from the CPU. Furthermore, the display screen scrolling method of the LED dot matrix display device controls the scrolling speed of the display screen by changing the timing interval of the address instruction from the timer to the CPU, so that the display screen of the display unit of the LED dot matrix display device is to scroll the
There is no need to rewrite the planes of the screen RAM one by one, the load on the CPU can be reduced, and the screen scrolling speed can be adjusted, so the screen can be scrolled smoothly.

According to the invention set forth in claim 3, in the display screen scrolling method of the LED dot matrix display device set forth in claim 2, the timing interval of the address instruction from the timer to the CPU is gradually increased when the screen scroll is stopped, and the scrolling is stopped. The display screen scrolling method of the LED dot matrix display device is used, which gradually shortens the interval between the timing of address instructions from the timer to the CPU when the screen scrolls and starts, so that the scrolling starts smoothly. Compared to the sudden stop and sudden start of the scroll screen, this eliminates the discomfort felt by the person looking at the LED dot matrix display.

(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 tosomatrix display device according to an embodiment of the present invention. Furthermore, the 9th
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 RAM (V-RA) that stores the content to be displayed in advance.
M) 7', an LED toso matrix display section 9, an LED control section 11 for realizing a scrolling 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 are connected to the address bus and data bus from the CPU.
The PUI specifies each component to be accessed via the address hash, writes image data to the V-RAM 7' via the data hash, and writes V-R to the screen controller 2.
It gives a display start address in AM7' and gives initial setting data to the LED control section 1].

The screen controller 2 uses, for example, a CRTC (CRT controller), which is originally used to control 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. -The screen controller 2 is provided with a built-in register, and when a value is written to this built-in register from the CPU, it is transferred to the V-RAM.
7', there is a function to scroll vertically and horizontally, and this is the basic principle of the movable window in this embodiment.

The second register includes a start address register in which a display start address is written, and a vertical smooth scroll register that performs vertical scrolling.

The MPX3 is a switch between the CPUI and the screen controller 2, and when operating the CPUI or the V-RAM 7', the bus driver 4 is open and image data is written to the V-RAM 7'. MPX3 does not connect screen controller 2 and V-RAM7', and screen controller 2 does not connect V-RAM7'.
When operating, the bus driver 4 is closed, and at this time the MPX 3 connects the screen controller 2 and the V-RAM 7'.

A constant dot clock is oscillated from the oscillator 5, multiplied by 78 times by the transmission frequency divider 10, and then one is output to the parallel/serial converter (P/S converter) 8, and the other is for the screen controller. The frequency divider 6 converts the signal into a 1/8 clock and outputs it to the screen controller 2. The screen controller 2 outputs a display address to the V-RAM 7' via the MPX 3 according to the timing of the input clock.

V-RAM7' (7) Storage capacity is the same as conventional V-RAM7
It is quite large compared to the storage capacity of
While the conventional V-RAM 7 had a brain capacity approximately equal to the display screen, the V-RAM 7' in this embodiment
It has a capacity that can store a considerable amount of the content that is scrolled and displayed.

Then, V-RAM7' receives a display address corresponding to the content to be output from the screen controller 2 to the LED dot matrix display section 9 through the MPX3, and transmits data corresponding to the display address to the frequency divider 1 for transmission.
0 output timing via P/S converter 8 and LED
It is output to the dot matrix display section 9 and displayed.

Note that since the contents of the V-RAM 7' are dot images, no character generator is provided in the circuit of this embodiment.

The LED control unit 11 has a horizontal smooth scroll register, and in the screen controller 2, the horizontal jump scroll (scrolling horizontally by one character) function starts at a start address shifted horizontally by one character. Although this can be achieved by giving it to the address register, it does not have a horizontal smooth scroll function that scrolls horizontally without displaying the middle stage of one character. The LED dot matrix display section 9 outputs a latch signal that provides the display timing of display data and a display address of the display line.

The LED dot matrix display section 9 is formed by a line of 16 x 16 dots of light emitting diodes (LEDs), and is controlled by the timing of the address instruction from the screen controller 2.
- Image data serially converted and output from the RAM 7' 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 the LED dot matrix display section 9 is given a clock from the transmission frequency divider 10,
A latch signal and a display line address are provided to the LED dot matrix display section 9 according to the setting values given to the D control section 11.

The image data is displayed on the LED according to the address of the display line.
Displayed at the display position on the dot matrix display section 9, the timing of the latch (latch timing) is set from CPtJl to the horizontal smooth scroll register to determine which dot is to be latched, and this setting value is displayed on the LED dot matrix display section 9. By varying the latch timing, smooth horizontal scrolling is achieved.

The CPUI also has a hard timer 12 that provides timing for switching screens. hard timer 1
2 performs an interrupt operation for the CPUI, and the CPU
The timing at which the display start address is written from the UI to the register of the screen controller 2 is controlled by the interrupt operation.

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 point is that the content to be displayed is written in advance in ', 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.

In Fig. 2, the screen controller 2 is connected to V-RAM 7'.
and a conceptual diagram when initializing the window. First, V-RAM7' is set to have a horizontal display memory width of M characters, and the display window is set to have one line display, which is set 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.

Vertical scrolling uses a start address register that specifies the display start address inside the screen controller 2, and a vertical smooth scroll that instructs to display mid-steps between the top and bottom of displayed characters in order to achieve smooth vertical scrolling in vertical scrolling. This can be done by rewriting the register.

In other words, by writing the start address of the display character from the CPU to the start address register of the screen controller 2, the display contents are written to the RAM 7'.
A window having the same width as the character string displayed on the display screen of the ED 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 the upper and lower middle 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, horizontal jump scrolling is performed using the start address register inside the screen controller 2, and scrolling is also performed by rewriting the horizontal smooth scroll register contained within the LED control unit 1.

In other words, by writing the start address of display characters from the CPUI into the start address register of the screen controller 2, a window is set on the V-RAM 7', and the characters in 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 1, the window moves horizontally and the characters jump and scroll horizontally.

In addition, each character is displayed in 16 dots horizontally, and the number of dots of the final character to be displayed is determined by the horizontal smoothing function in the LED control unit 11. By writing to the scroll register from the CPU, it is possible to display intermediate steps on the left and right sides of the displayed character, and by rewriting the number of dots in the horizontal smooth scroll register in the order of 1 to 16 dots, it is possible to scroll smoothly in the horizontal direction. I can do it.

The horizontal smooth scroll register included in the LED control unit 1 is specifically composed of a fixed number of dots counter and a variable number of dots counter. - Make initial settings so that a large number of characters can be displayed, count the number of dots up to the M character with the fixed number of dots counter, and then count the number of dots up to the M character with the variable number of dots counter with the end number of dots set. The number of dots 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 has received the latch signal will display on the display screen up to the number of dots corresponding to M111 characters 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 LEDF 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 a problem arises in that the display over the next line cannot be displayed correctly.

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 phosphor has the characteristic of remaining luminous even after being excited by electrons, so it can be recognized by the human eye as an image.
Light-emitting chips have no afterglow at all, so a normal LED panel has 16 rasters per line, 32 rasters for 2 lines, and 64 rasters for 4 lines, so it is difficult to display multiple lines like this with a single screen controller. Unlike CRT, if this is done, the brightness will inevitably decrease.

For the above reasons, it is preferable that the display panel of the LED dot matrix display section 9 driven by the screen controller 2 has one line of display characters.

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

According to this embodiment, the window with the display width corresponding to the panel of the LED dot matrix display section 9 is the V-RAM 7'.
By moving the top of the screen in response to address instructions from the screen controller 2, the display appears to scroll. 2
This is done using the scroll function of , which reduces the number of times the CPU'l goes to write display data to the V-RAM 7', freeing up CPU processing time and reducing the load on the CPU. There is, and -
Even if the display is finished, the structure of the V-RAM 7' has the advantage that play hacking can be performed immediately.

In the above LED dot matrix display device, this embodiment further controls the timing of screen switching and makes the switching time variable, thereby realizing smooth scrolling when the scrolling screen stops and starts. be.

The scrolling method for changing screens at variable intervals in the LED dot matrix display device of this embodiment will be explained using the conceptual diagram of the scrolling process shown in FIG.

Switching of the display screen of the L E D l' dittrix display section 9 is performed by an interrupt operation from the hard timer 12 to the CPUI, similar to the switching of planes in a conventional display device.

The feature of the scrolling method in the LED dot matrix display device of this embodiment is that, before starting the timer of the hard timer 12, a count set process is provided to count and store the number of times the timer has been started, and the number of times the timer has been started has been counted and stored. A variable (count variable) is stored in advance in a table or the like in the hard timer 12, and the timing of the interrupt operation is made variable in accordance with the value of the count variable, thereby making the timing of screen switching variable and adjusting the scrolling speed. The goal is to achieve smooth scrolling when the scroll screen stops and starts.

In other words, to reduce the scrolling speed to 1/2 of the current speed, just double the value of the count variable in Figure 4, and if you double the count variable one after another, the scroll speed will be inversely proportional to it. ℃ slow (can be.

For example, when the timer starts for the first time, if the count number of heart timer]2 is 1 and the count variable corresponding to the count number of 1 is set to 1 (second), then after 1 second the hard timer 12 will interrupts the CP
The UI is a screen control.

- Notify La 2 of the new display start address and switch the screen.

Next, when the timer starts for the second time, the count number of the hard timer 12 is 2, and if the count variable corresponding to the count number 2 is set to 2 (seconds), then after 2 seconds the heart timer code starts from 2. Interrupts CPU1 and
The UI notifies the screen controller 2 of the new display start address and switches the screen.

Furthermore, when the timer starts for the third time, the count number of the hard timer 12 is 3, and if the count variable corresponding to the count number 3 is set to 4 (seconds), then after 4 seconds, the hard timer 12 transfers the count value to the CPU 1. Interrupts the CPU
I notifies the screen controller 2 of the new display start address and switches the screen.

In this way, the first interrupt occurs one second after the timer starts, so the LED dot matrix display section 9
In this case, the first screen is displayed for only one second, and the screen is stopped for one second. The next second interrupt occurs 2 seconds after the timer starts, so the screen is frozen for 2 seconds, and the third interrupt is
Since it has been 4 seconds since the timer started, the screen has stopped for 4 seconds, and as shown in the smooth stop operation diagrams in Figure 5 (a) to (j), the screen movement gradually slows down. It looks like this, and you can control the screen to scroll smoothly and then stop at the end.

If the scrolling method is controlled by the hard timer 12 described above, for example, the screen switching interval can be set to 16 dots/
S (switching 16 dots in 1 second), then
Next, 8 dots/s (switching 16 dots in 2 seconds), 4 dots/s (switching 16 dots in 4 seconds), 2 dots/s (switching 16 dots in 8 seconds) , 1 dot/s (16 dots are switched in 16 seconds), and then it stops.

In addition, if smooth start is performed in the reverse order, the screen will scroll smoothly and the speed will gradually increase, as shown in the smooth start operation diagrams in Figure 6 (a) to (j). You can control the scrolling speed to be constant.

The scrolling method of the above embodiment realizes smooth scrolling by software control, but as another embodiment, as shown in the configuration block diagram of the LED dot matrix display device in FIG. Smooth scrolling can also be achieved through control.

The smooth scroll timer circuit 13 shown in FIG. 7 is a circuit that performs processing corresponding to the processing shown in FIG. 4 in a heart-like manner.

A method of controlling the smooth scrolling timer circuit 1B will be explained using the conceptual diagram of processing of the smooth scrolling timer circuit shown in FIG.

The smooth scroll timer circuit 13 includes a CPU
I to "start address" and "count set circuit where stop address J is written" 4, and count set circuit 1
4, and a hard timer circuit 12' that starts the timer according to the timing of the count output from the hard timer circuit 12'. The count setting circuit 4 sets a count variable corresponding to the count number and outputs it to the hard timer circuit 12'.

Then, in the count set circuit 14, the CPU 1
A count that controls the interrupt timing from the hard timer circuit 12' to the CPUI so that screen scrolling can be smoothly started and stopped when the "start address" and "stop address" are given from the hard timer circuit 12'. It calculates and sets variables.

First, to explain the process for smoothly stopping screen scrolling, write the "stop address" at which you want to stop scrolling from the CPU to the count set circuit 14 of the smooth scroll timer circuit 3, and Calculate from the "stop address" and set a count variable corresponding to the count number so that the screen scroll smooth stop process starts one character before the value of the "stop address", and
The timer count of the timer circuit 12' is given, an interrupt is made from the heart timer circuit 12' to the CPU, and the star! - Processing is performed to output the value of "display start address" to the address register.

At this time, in order to realize horizontal scrolling, by writing the "display start address" to the start address register in the screen controller 2, horizontal jump scrolling for one character is performed, and the horizontal scrolling in the LED control unit 11 is performed. Rewrites the value of the Smooth Scroll Renstar based on instructions from the CPU.

As a result, it is possible to display an intermediate stage when the displayed characters are scrolled by one character, and it is possible to perform smooth stop processing of screen scrolling even more smoothly.

In order to realize vertical scrolling, the start address register and vertical smooth scroll register in the screen controller 2 are rewritten. As a result, screen scrolling can be smoothly stopped even when scrolling up and down.

Then, at the timing when the hard timer circuit 12' is restarted, the count set circuit 4 is operated and repeats the above process with the next count number and count variable to perform smooth stop processing of screen scrolling.

This smooth stop processing means gradually lowering the scroll speed. In order to make the scroll speed equal to /2 of the current speed, the timer count value must be set to 2.
As stated in the explanation of FIG. 4, it is sufficient to double the amount. In other words, if you double the count variable one after another, the scroll speed will slow down in inverse proportion to it.

Furthermore, the smooth start process for screen scrolling may be performed by performing the process in reverse order to the above.

According to the display screen scrolling method in the LED dot matrix display device of this embodiment, the hard timer 12
Alternatively, the number of activations of the timer of the heart timer circuit 12' is counted, and the count variable is set in advance in the heart timer 12 or in accordance with the value of the count variable set in the smooth scroll timer circuit 13. Hard timer 12 or hard timer circuit]
By making the timing of the interrupt from 2' to the CPU 1 variable, the interval at which the display screen is switched on the LED dot matrix display section 9 is made variable, and the display screen scrolling method is adopted in which the screen scrolling speed can be adjusted.
At the start of the scrolling operation on the display screen φIn order to keep people's eyes following the stop, the scrolling speed is gradually increased from the stopped state until it reaches a certain constant scrolling speed, and when the scrolling is stopped, the scrolling speed is gradually increased from the constant speed. This allows for smooth scrolling, eliminating the discomfort caused by sudden starts and stops of conventional scrolling operations.
It has the effect of relieving discomfort.

Furthermore, according to the display screen scrolling method of this embodiment, the faster the desired scrolling speed is, the smoother the smooth start and smooth stop processing of this embodiment becomes.
This is highly effective in eliminating the discomfort caused by a constant scrolling speed, and the eyes will not get tired, making it possible to view the display screen for a long time.

(Effects of the Invention) According to the invention described in claim 1, a screen RAM in which display contents are written in advance, and a window setting control that is the same as the display contents of the display section of the LED dot matrix display device are provided on the screen RAM. a screen controller that performs the process, a CPU that instructs the screen controller to address on screens RA~1,
The LED dot matrix display device includes a timer that gives the timing of address instructions to the CPU, and an LED dot matrix display that controls the screen controller based on the address instructions from the CPU, operates the window on the screen RAM, and scrolls the display screen on the display unit. There is no need to sequentially rewrite the planes of the screen RAM to scroll the display screen of the section, which has the effect of reducing the load on the CPU.

According to the invention set forth in claim 2, in the LED dot matrix display device set forth in claim 1, the window provided under the control of the screen controller on the screen RAM in which the content to be displayed is written in advance is controlled by the CPU. The display screen scrolling method of the LED dot matrix display device controls the scrolling speed of the display screen by changing the timing interval of the address instruction from the timer to the CPU. It is no longer necessary to rewrite the screen RAM brain sequentially to scroll the screen, which reduces the load on the CPU.Furthermore, since the screen scrolling speed can be adjusted, the screen can be scrolled smoothly, making the scrolling screen easier to see. effective.

According to the invention set forth in claim 3, in the display screen scrolling method of the LED dot matrix display device set forth in claim 2, the timing interval of the address instruction from the timer to the CPU is gradually increased when the screen scroll is stopped, and the scrolling is stopped. The display screen scrolling method of the LED dot matrix display device is used, which gradually shortens the interval between the timing of address instructions from the timer to the CPU when the screen scrolls and starts, so that the scrolling starts smoothly. Compared to the sudden stop and start of the scrolling screen, this eliminates the discomfort felt by the person looking at the LED dot matrix display and has the effect of not tiring the eyes.

[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 the screen controller, and Fig. 3 shows the vertical and horizontal scrolling states in V-RAM. FIG. 4 is a conceptual diagram of the scrolling process of this embodiment, and FIGS. 5(a) to (j)
FIG. 6(a) is a smooth stop operation diagram of this embodiment.
~(j) is a smooth start operation diagram of this embodiment, FIG. 7 is a block diagram mainly consisting of hardware that realizes a scrolling method according to another embodiment, and FIG. 8 is a diagram for smooth scrolling of FIG. 7. A conceptual diagram of the processing of the timer circuit, Figure 9 is a circuit configuration block diagram of a conventional LED dot matrix display device, and Figure 10 is a diagram of the conventional LED display capacity and V-RAM.
11(a) to (g) are stop operation diagrams in conventional scrolling, and FIG. 12(a) to (g)
13 is a diagram showing the start operation in conventional scrolling, FIG. 13 is a diagram showing the connection between the CPU and the hard timer, and FIG. 14 is a conceptual diagram of scrolling processing in the conventional method. 1... CPU 2... Screen controller 3... Multiplexer 4... Bus driver 5... Oscillator 6... Screen Controller frequency divider 7...
Screen RAM 8...Parallel/serial converter 9...
- LED dot matrix display unit 10...transmission frequency divider 11...LED control unit 12...hard timer 13...smooth scroll timer circuit 14...
・Count set circuit Fig. 2 (V-RAM 7) Fig. 4 8th factor, 1-no -7-no ~no
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ノ 、2 -ノ
,. Figure 1o: 13th cause, 11th ward, 12th cause, 14th ward

Claims (3)

[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. a CPU that provides an address to a register of the screen controller; and a timer that provides an output timing of the address output from the CPU to the CPU; By writing to the register of the controller, the screen RA
An LED dot matrix display device characterized in that a window corresponding to a display screen is set on M. (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 to move the window set on the screen RAM, and the address output from the timer to the CPU is A display screen scrolling method for an LED dot matrix display device, characterized in that the scrolling speed of a display screen in a display unit is controlled by varying timing intervals. (3) In the display screen scrolling method of the LED dot matrix display device described in item 2, the scrolling speed is gradually increased when the screen starts scrolling, and the scrolling speed is gradually slowed and stopped when the screen scrolling is stopped. 1. A display screen scrolling method for an LED dot matrix display device, characterized in that the scrolling speed is controlled.