JP2822421B2 - Scanning display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a liquid crystal display, a plasma display,
The present invention relates to a scanning display device such as a CRT display.

[Prior Art] Conventionally, in a scanning display device, the scanning direction is always constant, and when the display screen is rotated by 90 degrees, the scanning direction also rotates by 90 degrees with it, and in the case of the bitmap graphic mode, The display as shown in FIG. 6 is performed in the direction, and when the display is rotated 90 degrees in the vertical direction, the display becomes as shown in FIG. Usually, it is necessary to display this in the vertical direction as shown in FIG.

That is, it is necessary to perform the same display as scanning in the horizontal direction while scanning in the vertical direction.

[Problems to be Solved by the Invention] Generally, only commercially available character generators (hereinafter abbreviated as C / G) are suitable for scanning in the horizontal direction. In order to perform the above, in the above-described conventional technology, it is necessary to perform vertical / horizontal conversion processing on the data expanded to the VRAM by software, and there is a disadvantage that the time required for the expansion to the VRAM is increased and the response speed of the display is reduced.

More specifically, C / G data is stored in the pattern shown in FIG. In the case of scanning in the horizontal direction (8 dots × 8 dots in this example), this data may be written as it is at the corresponding address of the VRAM as shown in FIG.

However, when scanning in the vertical direction, the C / G data cannot be used as it is, and must be converted to the data shown in FIG. In order to perform this processing by software, it is necessary to read the C / G data eight times and take in the necessary bits, which increases the processing time.
The display response speed is significantly slower than in the case of scanning in the horizontal direction.

It is an object of the present invention to provide a display with a high response speed by eliminating the processing by software and responding by hardware.

[Means for Solving the Problems] A scanning display device according to the present invention includes a drive circuit including a register for setting display data and a driver for outputting the data of the register. Wherein the drive circuit scans the display screen by the drive circuit to perform display, wherein the drive circuit switches between common data and segment data in response to a common / segment switching signal. A data selector to be set in the register; and a power selector for switching and applying a common driver drive power supply and a segment driver drive power supply to the driver in accordance with the common / segment switching signal. Regardless of whether the display screen is displayed vertically or horizontally by the / segment switching signal, The inspection direction is a horizontal direction.

[Operation] In the present invention, no special processing of software is required for both the vertical display and the horizontal display, so that the display response speed does not decrease.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Here, a liquid crystal driving circuit will be described as an example.

FIG. 1 is a block diagram of a liquid crystal driver according to one embodiment of the present invention.

V0 to V5 are power supplies for driving a liquid crystal display, V0, V2, V3, and V5 are segment output drive levels, and V0, V1, V4, and V5 are common output drive levels and enter the voltage & control selector 71.
S / C is a segment / common switching signal, YDI is a serial shift data input for common, and LP is a transfer clock for common serial data and a latch pulse of data.

XD3 to XD0 indicate segment display data input, and XSCL indicates a segment display data transfer clock.

This driver can switch the driver output between segment and common by the external signal S / C. In this driver, the output of the register 2 is connected to the driver output. Whether the input of the register 2 is set to the common data or the segment data is switched by the S / C signal.

The segment driver uses the V0, V2, V3, and V5 levels, and the common driver uses the V0, V1, V4, and V5 levels.
Switching between 3 and V1 and V4 is also performed at the same time.

With such a configuration, the segment /
Common switching becomes possible.

FIG. 2 shows a liquid crystal driving circuit using the liquid crystal driver of FIG. In this circuit, four drivers 81, 82, 83 and 84 of A, B, C and D are mounted in the horizontal direction of the panel, and two drivers 86 and 87 of E and F are mounted in the vertical direction.

When the panel is displayed horizontally, four drivers 81 to 84 of A, B, C, and D are used as segment outputs, and two drivers 86 and 87 of E and F are used as common outputs.

In the case of displaying vertically, four drivers A, B, C, and D have common outputs, and two drivers E and F have segment outputs.

This allows the scanning direction to be always horizontal regardless of whether the panel is displayed vertically or horizontally, eliminating the need for software to process the expanded data to VRAM vertically and horizontally. The disadvantage that the display response speed is reduced can be solved.

Although the liquid crystal driving circuit has been described here, the present invention is not limited to the liquid crystal display device, but can be applied to all scanning display devices.

[Effects of the Invention] As described above, in a scanning type display device capable of rotating the display by about 90 degrees between the vertical display and the horizontal display, the scanning direction is always switched so that the scanning is always performed in the horizontal direction. A display with a fast response speed can be realized by eliminating software processing.

[Brief description of the drawings]

FIGS. 1 to 5 are schematic diagrams for explaining the present invention. FIG. 1 is a block diagram of a liquid crystal driver, and FIG. 2 is a diagram showing one embodiment of FIG. FIG. 3 to FIG. 5 are diagrams showing a general C / G data structure. 6 to 8 are diagrams for explaining the prior art.
FIG. 7 is a view showing a horizontally long display, FIG. 7 is a view showing a display example obtained by rotating the display of FIG. 6 by 90 degrees, and FIG. 8 is a view showing a practical display example of a vertically long display. V0 to V5: LCD drive power supply S / C: Segment / common switching signal VDI: Common serial shift data input LP: Common serial data transfer clock and data latch pulse XD3 to 0: Segment display data input XSCL: Segment display data transfer clock

Claims (1)

(57) [Claims] A drive circuit including a register for setting display data and a driver for outputting data of the register is provided in a vertical direction and a horizontal direction of a display screen, respectively.
A scanning display device for scanning and displaying the display screen by the drive circuit, wherein the drive circuit switches between common data and segment data in accordance with a common / segment switching signal and sets the data in the register. A data selector; and a power selector for switching and applying a common driver drive power supply and a segment driver drive power supply to the driver according to the common / segment switching signal. A scanning display device, wherein a scanning direction is a horizontal direction regardless of whether the display screen is displayed vertically or horizontally.