JP2595243Y2 - Microcomputer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microcomputer display system.

[0002]

2. Description of the Related Art Laptop type or notebook type microcomputers are becoming widespread due to their good portability. One of the problems common to such microcomputers is power consumption.
In other words, these microcomputers use a battery as a portable power supply, but currently only operate for about 2 to 5 hours under normal operation. For this reason, a system for saving power of display has already been invented by the present inventors.
FIG. 2 shows a block diagram of the system in a normal mode. The display controller 103 stores the LCD data 108 and L
The CD synchronizing signal 109 is output to the LCD circuit 107 through the image circuit 105, and the LC synchronization signal 109 is output immediately before switching to the power saving mode.
The D data is stored in the holding memory 106 in accordance with the LCD synchronization signal 109 based on the data transfer signal generated from the display controller 103. FIG. 3 is a block diagram of the system in a power saving mode. Display controller 10
3 is stopped and the pseudo LCD generated from the image circuit 105
In accordance with the synchronization signal 201, data in the holding memory 106 is output to the LCD circuit 107 via the image circuit 105 as LCD holding data 202. At the same time, the image circuit 1
The pseudo LCD synchronization signal 201 generated from 05 is output to the LCD circuit.

[0003]

In the above low power consumption display system, the signal system to the LCD circuit is composed of LCD data and L signal.
The image circuit 105 is complicated because the set of the CD synchronization signal 109 and the set of the LCD holding data and the pseudo synchronization signal are input by switching.

An object of the present invention is to solve this problem and to make a display low power system easier to manufacture.

[0005]

To achieve the above object, the present invention provides a central processing unit, a first image display storage circuit, a second image display storage circuit for fixed image display, and a display image generation circuit. A microcomputer having a display control circuit and a display element and having a normal power consumption display mode and a low power consumption display mode, wherein the display control device newly generates fixed image data stored in the second image storage circuit. The image data is displayed on the display element in accordance with the synchronized signal, and the image data based on the data stored in the first image display storage circuit output from the display image generation circuit is stored in the second image display storage circuit. Remember.

[0006]

In the low power consumption display system described above, the signal system to the LCD circuit 107 is switched between a set of the LCD data 108 and the LCD synchronization signal 109 and a set of the LCD holding data 202 and the pseudo synchronization signal 201. 105
Becomes complicated. Therefore, when the display controller 103 returns to the normal operation due to a change in the contents of the VRAM 104 or the like, the LCD data 108 is stored in the holding memory circuit 106 and the contents of the holding memory 106 are continuously transferred to the LCD circuit 107. That is, the signal system to the LCD circuit 107 is always only one set of the set of the LCD holding data 202 and the pseudo synchronization signal 201.

[0007]

FIG. 1 is a block diagram showing an embodiment of a normal mode according to the present invention. Here, the CPU 102 corresponds to a central processing unit such as 80C88 of Intel Corporation. V
The RAM 104 is a video memory using a storage circuit element using a dynamic ram or the like used in a microcomputer as is well known, and corresponds to a first image display storage circuit. The holding memory circuit 116 is a circuit including a memory circuit element capable of reading and writing asynchronously using a dynamic ram or the like capable of storing LCD data, and a second circuit for fixed image display.
Of the image display circuit. The display controller 103 is a microcomputer circuit called an ordinary VGA controller or the like, and corresponds to a display image generating circuit.
The image circuit 105 corresponds to a display control circuit. The LCD circuit 107 corresponds to a display element. Hereinafter, the system of the present embodiment will be described.

The display controller 103 has a VRAM 104
Is scanned, and a predetermined operation is performed. The resulting image data is converted for LCD and converted to LCD data 10.
8 and at the same time, outputs an LCD synchronization signal 109 for driving the LCD. The image circuit 105 outputs the LCD holding data 202 and the LCD synchronization signal 201 to the LCD circuit 107, and outputs the LCD holding data 202 to the pseudo synchronization signal 201.
Is displayed on the LCD according to. In the meantime, LCD data 10
9 is stored in the holding memory circuit 10 according to the LCD synchronization signal 109.
6 and stored. At the time of the low power consumption display mode, it is completely the same as the conventional one.

[0009]

According to the microcomputer having the structure of the present invention, the conventional low-power display system can be further simplified.

[Brief description of the drawings]

FIG. 1 is a block diagram in a normal mode of an embodiment based on the present invention.

FIG. 2 is a block diagram of a conventional microcomputer display unit in a normal mode.

FIG. 3 is a block diagram of a conventional microcomputer display unit in a power saving mode.

[Explanation of symbols]

 102 CPU 103 Display controller 104 VRAM 105 Image circuit 106 Retention memory circuit 107 LCD circuit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G09G 3/36 G06F 1/00 332Z

Claims (1)

(57) [Scope of request for utility model registration] 1. A central processing unit, a first image display storage circuit , a second image display storage circuit, a display element, and a central processing unit.
Data in the first image display storage circuit.
The display image generation circuit for outputting a physical image data, second image
Input and output image data with the image display storage circuit and display
A display control circuits to output image data to the device, in a microcomputer having a normal power consumption display mode and the low power consumption display mode, the normal power consumption display mode
In the display control circuit, the synchronization generated by the display control circuit
Image data of the second image display storage circuit based on the signal;
Is transferred to the display element and the display image generation circuit
Transfers image data to the second image display storage circuit for low power consumption
In the power display mode, the display image generation circuit is stopped and
The output of the image data is stopped at the
Image data of the second image display storage circuit based on the signal;
Which transfers the data to a display element .