JP3484855B2 - Drive - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a matrix type display device and a scroll control method in which a minimum unit of horizontal movement of a character on a screen is a dot unit constituting a character display.

[0002]

2. Description of the Related Art FIG. 7 shows an example of horizontal movement in dot units. In FIG. 7, a display example in which the display in b) is displayed by horizontally moving the display in a) by 2 dots is shown.

In the conventional matrix display device and scroll control method, horizontal scroll in dot units is realized by the following method.

An example of a conventional example is shown in FIG. 6 and will be described below.

In FIG. 6, the conventional scroll control method is controlled by the reference clock 8 and the display digit address 1
3 to the character code storage unit 2, scroll control unit 2
9, a timing generation circuit 1 for supplying a timing signal to the signal line driving circuit 6, a shift clock 32 to the signal line drive circuit 6, a timing signal to the character code storage unit 2 and the character generator 3, and a character code 14. A character code that is received and stored via a bus, a data bus, and a control bus, and the display digit address 13 is given from the timing generation circuit 1 and stored in correspondence with the display digit address 13 to the character generator 3. The storage unit 2, the character generator 3 that outputs the character pattern 15 according to the input character code 14 to the parallel-serial conversion unit 30, and the time-series parallel character pattern that is controlled by the timing signal and is input in time series. Convert to serial serial character pattern and output to signal line drive circuit 6 The parallel-to-serial conversion unit 30 and the scroll control unit 29 which receives the output of the timing generation circuit 1 and generates the timing of the parallel-to-serial conversion unit 30 and the shift clock 32 of the signal line drive circuit 6, and is controlled by the timing signal. The parallel line-to-serial converter 30 is composed of the signal line drive circuit 6 which takes in the serial character pattern 35 and outputs it to the signal line.

When performing horizontal scrolling in dot units by such a matrix type display device and scroll control method, the shift clock 32 generated from the scroll control unit is set to an arbitrary phase according to the number of dots scrolled by the scroll control unit 29. Alternatively, it is performed by controlling the number of times as desired.

[0007]

In the above-mentioned conventional matrix type display device and scroll control method, when character display is performed, a character pattern parallel to the time series of the character generator is serialized in time series by the parallel / serial conversion unit. In order to display one scanning line of the liquid crystal panel, a reference clock of at least the number of display dots in one scanning line is required in order to display the data for one scanning line of the liquid crystal panel. For example, the number of characters displayed on the LCD panel is 2
Assuming that the pixel configuration is row × 16 characters and each character is horizontal 6 × vertical 8 dots and the frame frequency is 100 Hz, the reference clock needs to be 145 KHz or higher.
The frequency is extremely higher than that of a scanning signal of KHz or the like.

It is an object of the present invention to realize, at a low speed, a matrix type display device in which the minimum unit of horizontal movement of characters on the screen is a dot unit constituting a character display.

[0009]

A drive device for solving the problem is a drive device of a matrix type display device driven by line-sequential scanning, in which a character code is stored and a screen display of the display device is performed. A character code storage unit that outputs a predetermined character code in response to the input of a display digit address that specifies the display position of a character on the upper side, and a character pattern that corresponds to the character code output by the character code storage unit A character generator that outputs the character pattern, a character pattern storage unit that stores the output character pattern, and a dot unit for the character pattern that is output from the character generator following the output of the character pattern storage unit and the time series. Character pattern shifted by a predetermined bit according to the value of the dot scroll register that stores the scroll amount in A character pattern conversion section for generating,
A signal line drive circuit which is guided to the display digit address and holds the output data from the character pattern conversion unit in any one of a plurality of latches having a plurality of bits and outputs the data to the signal electrode of the display device. And a timing generation circuit for generating the display digit address and the timing signal,
Further, each of the character code storage unit, the character generator, the character pattern conversion unit, and the signal line drive circuit has a delay unit that has a delay time that is the same as or longer than the respective operation time. And the delay means are connected in series,
The operation of the first-stage delay means of the delay means connected in series by the reference clock is started, and during the time when each of the delay means operates, the corresponding character code storage unit, the character generator, the character Any one of the pattern conversion unit and the signal line drive circuit is operated to receive the output of the delay unit at the final stage of the delay unit connected in series, the operation of the delay unit and the character code storage unit, The operation of the character generator, the character pattern conversion unit, and the signal line drive circuit is stopped, and the signal line output for one scanning line is configured to end at the character display digit + 1 reference clock of one time. To do. Further, in a matrix-type display driving device driven by line-sequential scanning, a scroll amount in units of digits is stored for a display digit address designating a display position of a character on a screen display of the display device. A display digit address conversion unit that generates a display digit address shifted by a predetermined digit according to the value of the digit scroll register, and a character code that outputs the character code stored in advance by the output of the display digit address conversion unit A storage unit, a character generator that outputs a character pattern corresponding to the character code output by the character code storage unit, and a character pattern storage unit that stores the output character pattern,
For the character pattern output from the character generator subsequently to the output of the storage means and the time series, a character pattern obtained by shifting a predetermined bit according to the value of the dot scroll register in which the scroll amount in dots is stored. The generated character pattern conversion unit and the output data from the character pattern conversion unit, which is guided to the display digit address and is held in any one of a plurality of latches having a plurality of bit numbers, holds the signal of the display device. A signal line drive circuit for outputting to the electrodes, and a timing generation circuit for generating the display digit address and the timing signal, and further,
The character code storage unit, the character generator,
Each of the character pattern conversion unit and the signal line drive circuit has a delay unit that has a delay time that is equal to or longer than the operation time of the respective unit, and the delay units are connected in series and are connected by a reference clock. The operation of the first-stage delay means of the delay means connected in series is started, and within the time when the respective delay means operate, the corresponding character code storage unit, the character generator, and the character pattern conversion unit. And each of the signal line drive circuits are operated to receive the output of the delay means at the final stage of the delay means connected in series, the operation of the delay means, the character code storage unit, the character generator, The operation of the character pattern conversion unit and the signal line drive circuit is stopped, and the signal line output for one scanning line is Characterized in that it is configured to terminate the display digits + one of the reference clock of characters.

[0010]

[0011]

[0012]

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The matrix type display device of the present invention, when transferring a character pattern signal of a plurality of bits obtained by a character generator to a signal line drive circuit,
A clock for displaying one scanning line by converting a character pattern into a plurality of character patterns scrolled in dot units and sequentially transferring in parallel to the signal line drive circuit for each number of horizontal dots forming one character. It is intended to reduce the number, and a scroll register that stores the scroll amount in dot units in the middle of the character generator and the signal line drive circuit, a latch that stores the previously read character pattern, and a read from the character generator this time. It is characterized in that a character data conversion unit constituted by a selector that obtains dot-scrolled character data from the character data, the output of the above-mentioned latch, and the value of the scroll register is provided.

Further, the signal line drive circuit is constituted by a plurality of latches for sequentially latching parallel character patterns at the display positions of characters on the screen display indicated by the display digit address output from the timing generation circuit which operates with the reference clock. The character code storage unit is configured by a timing signal obtained through a delay circuit having an operation time equal to or longer than each of the character code storage unit, the character generator, and the character data conversion unit, using the reference clock as a trigger. The operation of the character generator and the character data conversion unit and the latch of the character pattern to the signal line drive circuit are sequentially operated asynchronously with respect to the reference clock, so that the character code storage unit and the character generator within one clock of the reference clock. , Each operation of character data converter and signal line There are features of the present invention to a scroll control method to end the latching character codes to the dynamic circuit.

Embodiments of the present invention will be described below step by step.

(1) First embodiment FIG. 1 is a block diagram showing a first embodiment of the present invention.

In the embodiment shown in FIG. 1, the display digit address 13 which is the output of the timing generation circuit 1 controlled by the reference clock 8 stores the character code written via the address bus, the data bus and the control bus. Is input to the character code storage unit 2
The character code 14 of the corresponding display digit and the raster address 17 input from the timing generation circuit 1, which is the output of the, are input to the character generator 3, and the character pattern 15 of the corresponding character position on the screen and the corresponding line is displayed on the character generator 3. Is output to the character pattern conversion unit 5. The character pattern conversion unit 5 creates a time-series parallel character pattern 16 scrolled in dot units in accordance with the value of the dot scroll register 4 in which the information on the scroll amount in dot units is written via the data bus and the control bus. And generate a character pattern 1 on the signal line drive circuit 6.
6 are sequentially latched by the number of horizontal dots for one character.

Here, the character pattern conversion unit 5 is shown in FIG.
An example of the configuration is shown in FIG. FIG. 4 shows an example in which the number of dots in the horizontal direction for one character is 6 dots. The character pattern conversion unit 5 selects a character pattern 27, which is held in the latch 25 and has a horizontal dot number of one character read previously, and a character pattern 15 having a horizontal dot number of one character, which is read this time, from the selector. By way of 26, the character pattern 16 having the number of dots in the horizontal direction for one character to be sent to the signal line drive circuit 6 is generated. Character pattern 1
As shown in FIG. 4, the occurrence of No. 6 is determined by the value of the dot scroll register, which part of the previously read character pattern and the currently read character pattern is extracted, that is, how much is scrolled.

Next, the operation of one scanning line in the embodiment of FIG. 1 will be described with reference to the timing chart of FIG. In this timing chart, the operation for one scanning line is performed by the number of display digits + 1 the reference clock.

In FIG. 5, while the reference clock is "H", the reading of the character code, the reading of the character pattern, and the latching of the signal line drive circuit are performed, and the display digit address and the raster address change at the fall of the reference clock. Show.

The reference clock is input by the number of display digits + 1 times for data transfer of one scanning line. The first time of this reference clock is performed to hold the character pattern read from the character generator in the latch of the character pattern conversion unit, and the character pattern is not held in any of the plurality of latches of the signal line drive circuit.

Then, in the second and subsequent reference clocks, when the reference clock rises, the character code of the corresponding display digit is read from the character code storage unit, the character pattern is read from the character generator, the character pattern conversion is performed,
The operation is performed in the order of latching to the signal line driving circuit, and when the character pattern is latched to the signal line driving circuit, a feedback signal from the signal line driving circuit causes a character code storage unit including a RAM and a ROM, and a character generator. Is precharged in preparation for the next reading, and the read character pattern is latched by the latch of the character pattern conversion unit guided by the display digit address. After that, this operation is repeated until the number of display digits + 1 clock.

The inverters 9 and 33 shown in FIG.
And the NAND gates 10, 11 and 12 and the character code storage unit 2, the character generator 3, the character pattern conversion unit 5 and the signal line drive circuit 6 have the same or different operation time difference delay elements. 7 and using the rising edge of the reference clock 8 as a trigger, the asynchronous operations are sequentially performed, so that the respective operations can be completed within one cycle of the reference clock as shown in the timing chart of FIG.

(2) Second Embodiment A configuration diagram showing a second embodiment of the present invention is shown in FIG. 2 and will be described below.

In the embodiment shown in FIG. 2, a digit scroll register 18 written via a data bus and a control bus is provided between the timing generation circuit 1 and the character code storage unit 2, and the output of the digit scroll register 18 and timing generation. A display digit address conversion unit 19 is provided from the display digit address 13 output from the circuit 1. By giving the converted display digit address 20 to the character code storage section 19 via the display digit address conversion section 19, horizontal scrolling in display digit units is also possible.

In FIG. 2, by combining the dot scroll register 4 for performing horizontal scrolling in dot units, the character pattern conversion unit 5, the digit scroll register 18, and the display digit address conversion unit 19, any number of characters can be displayed.
It is possible to display the screen by horizontally scrolling an arbitrary number of dots.

The configuration and operation of the parts other than the above are the same as those in the first embodiment shown in FIG.

[0028]

According to the matrix type display device and the scroll control method of the present invention, the horizontal scroll of the screen is
It is possible for each dot that constitutes a character.

Further, in the present invention, since the operating frequency of the circuit can be lowered, it is possible to use an element or circuit having a low operating frequency. For example, the number of characters displayed on the LCD panel is 2 lines ×
With 16 characters, each character has a pixel configuration of horizontal 6 x vertical 8 dots,
When the frame frequency is 100 Hz, the frequency of the reference clock may be 27 KHz. Therefore, the circuit can be simplified and the device can be downsized. In particular, the character code storage unit composed of RAM and ROM and the character generator can have a simplified element structure, so that the chip size can be reduced when they are arranged on a semiconductor substrate. Further reduction of operating frequency i (current consumption) =
c (load capacity), v (operating voltage), f (operating frequency)
It is possible to significantly reduce the current consumption of the circuit represented by the formula.

By providing both a dot scroll register and a digit scroll register in addition to the above two points, finer screen scrolling can be realized.

The present invention can be widely applied to matrix type display devices such as liquid crystal, electroluminescent or fluorescent display tubes.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a second embodiment of the present invention.

FIG. 3 is a diagram showing a configuration example of a character pattern conversion unit of the present invention.

FIG. 4 is a diagram showing an operation of a character pattern conversion unit of the present invention.

FIG. 5 is a timing chart for explaining a matrix display device and a scroll control method of the present invention.

FIG. 6 is a diagram showing an example of a conventional scroll control method.

FIG. 7 is a diagram illustrating an operation example of horizontal movement of a character on a screen performed in dot units that form a character display.

[Explanation of symbols]

1 Timing generation circuit 2 character code storage 3 character generator 4-dot scroll register 5 character pattern converter 6 Signal line drive circuit 7 Delay circuit 8 reference clock 9, 21, 33, 34 Inverter NAND gates 10, 11, 12, 22, 23, 24 13 Display digit address 14 character code 15 character pattern 16 Character pattern after conversion 17 raster address 18 digit scroll register 19 Display digit address converter 20 Character pattern after conversion 25 latch 26 Selector 27 Previous read data 28 Latch clock 29 Scroll controller 30 Parallel-to-serial converter 31 Timing signal 32 shift clock 35 Serial character pattern

Continuation of front page (51) Int.Cl. ⁷ identification code FI G09G 5/34 G09G 5/34 EM (58) Fields investigated (Int.Cl. ⁷ , DB name) G09G 3/20 660 G09G 3/20 611 G09G 3/20 612 G09G 3/36 G09G 5/34

Claims (2)

(57) [Claims] 1. A driving device for a matrix type display device driven by line-sequential scanning, wherein a character code is stored and a display digit address for designating a display position of the character on the screen display of the display device is inputted. Then, in response to this, a character code storage unit that outputs a predetermined character code, a character generator that outputs a character pattern corresponding to the character code output by the character code storage unit, and a memory unit that stores the output character pattern A character pattern storage unit for outputting the character pattern storage unit and the character pattern output from the character generator following the output of the character pattern storage unit and the time series, and A character pattern conversion unit that generates a character pattern that is shifted by a predetermined bit by the display digit adder. A signal line drive circuit for holding the output data from the character pattern conversion unit in any one of a plurality of latches having a plurality of bit numbers and outputting the data to the signal electrode of the display device. A timing generation circuit for generating a display digit address and a timing signal, and further, for each of the character code storage section, the character generator, the character pattern conversion section and the signal line drive circuit, a respective operation time and Each delay means has a delay time of the same or more, and each delay means is connected in series, and the operation of the delay means in the first stage of the delay means connected in series by the reference clock is started. During the time when each of the delay units operates, the corresponding character code storage unit and the character generator Lator,
Either the character pattern conversion unit or the signal line drive circuit is operated, and the output of the delay unit at the final stage of the delay unit connected in series is received, and the operation of the delay unit and the character code storage unit. The operation of the character generator, the character pattern conversion unit, and the signal line drive circuit is stopped, and the signal line output for one scanning line is configured to end at the display digit of the character + the reference clock of one time. Characteristic drive device. 2. A drive device for a matrix type display device driven by line-sequential scanning, wherein a scroll amount in a digit unit for a display digit address designating a display position of a character on a screen display of the display device. The display digit address conversion unit for generating a display digit address shifted by a predetermined digit according to the value of the stored digit scroll register, and the output of the display digit address conversion unit is input and the character code stored in advance is output. A character code storage unit, a character generator that outputs a character pattern corresponding to the character code output by the character code storage unit, a character pattern storage unit that stores the output character pattern, and an output of the storage unit. For the character pattern output from the character generator following the time series, in dot units A character pattern conversion unit that generates a character pattern shifted by a predetermined number of bits according to the value of the dot scroll register in which the crawl amount is stored, and one of a plurality of latches that are guided to the display digit address and that have a plurality of bit numbers. A signal line drive circuit that holds the output data from the character pattern conversion unit in the latch and outputs the data to the signal electrode of the display device; and a timing generation circuit that generates the display digit address and the timing signal. Furthermore, each of the character code storage unit, the character generator, the character pattern conversion unit, and the signal line drive circuit has a delay unit having a delay time equal to or longer than the respective operation time, The respective delay means are connected in series, and are connected in series by the reference clock. Operation of the first stage of the delay means of the extending means is started, the time during which the respective delay means operates, said corresponding character code storage unit, the character generator,
Either the character pattern conversion unit or the signal line drive circuit is operated, and the output of the delay unit at the final stage of the delay unit connected in series is received, and the operation of the delay unit and the character code storage unit. The operation of the character generator, the character pattern conversion unit, and the signal line drive circuit is stopped, and the signal line output for one scanning line is configured to end at the display digit of the character + the reference clock of one time. Characteristic drive device.