JPH04287089A - Plasma display device - Google Patents

Abstract

PURPOSE:To prevent the abnormal display of a plasma display device incorporating a display controlling even when the scanning output period of the display controller is unsettled or a display command is given in this period. CONSTITUTION:The plasma display device provided with an X-Y matrix type plasma display unit 105 on which a picture is displayed based on a display control signal SGC by plasma discharging light emission and a display control means 104 which outputs the display control signal SGC based on an input SIN from the external related to picture display consists of a power-on detecting means 101 which detects power-on of the plasma display device to output a power-on signal SPW, a command detecting means 102 which detects supply of an initializing command from the input SIN to output a command detection signal SCD, and a display inhibiting means 103 which inhibits the display operation of the plasma display unit 105 till the output of the command detection signal SCD.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device, and more particularly to a plasma display device having a built-in display controller.

0002

[Prior Art] A conventional plasma display device uses C.
It was provided to users with a unique CRT interface compliant specification without using a display controller such as an RTC (CRT controller) or an LCDC (LCD controller). However, recently, as demand has increased for devices that can be connected to a CRT interface that can be directly connected to a host computer, plasma display devices that have a built-in CRTC or LCDC that can be driven by this CRT interface have come into use. .

0003

[Problems to be Solved by the Invention] However, in plasma display devices equipped with these display controllers, after the power is turned on, the scanning output period from the display controller cannot be kept constant by inputting a parameter set (initialization) command from the host computer. The period until the parameter is set incorrectly (initialization)
When processing other commands such as a display command without executing a command, no action is taken on the display. For this reason, there is a problem in that an abnormal display may occur during a period where the scan output cycle from the display controller is indefinite as described above, and when a display command is given during that period.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a plasma display device that can prevent abnormal display even when the scanning output cycle of a display controller is indefinite and a display command is given during that period. .

[0005]

[Means for Solving the Problems] In order to solve the above problems, the invention according to claim 1 displays an image by plasma discharge light emission based on a display control signal SGC, as shown in the principle explanatory diagram of FIG. In a plasma display device including an X-Y matrix type plasma display unit 105 and a display control means 104 that outputs a display control signal SGC based on an external input SIN regarding image display, power is turned on to the plasma display device. A power-on detection means 101 detects input of the initialization command from input SIN and outputs a power-on signal SPW, and a command detection means 102 detects input of an initialization command from input SIN and outputs a command detection signal SCD. Display prohibiting means 103 for prohibiting the display operation of the plasma display unit 105 until the detection signal SCD is output.
It is composed of the following.

[0006]

According to the invention as set forth in claim 1 having the above-mentioned configuration, in the principle explanatory diagram of FIG. The display prohibition means 103 immediately sends a display prohibition signal PHB to the XY matrix type plasma display unit 105.
is output, and the display operation of the XY matrix type plasma display unit 105 is prohibited. After that, an initialization command is input from the host computer, and when the command detection means 102 detects this from the external input SIN,
The command detection signal SCD is output to the display inhibiting means 103. As a result, the display inhibiting means 103 cancels the display inhibiting signal PHB outputted to the XY matrix type plasma display unit 105, and henceforth, display operations are enabled in response to commands from the host computer.

As a result, as shown in FIG. 4, the X-
By placing the Y matrix type plasma display unit 105 in a display prohibited state, abnormal display during that period can be prevented. That is, even during a period in which the scanning output cycle of the display controller (not shown) in the display control means 104 is indefinite, and even if a display command is given during that period, the X-Y matrix type Since the display operation of the plasma display unit 105 is forcibly prohibited, abnormal display is prevented.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a diagram showing the configuration of an embodiment of the present invention. As shown in the figure, this plasma display device 100A includes an interface buffer circuit 1 that receives external inputs, and a drive signal A based on these inputs.
A display controller 2 that outputs CT, a power supply unit 8 that supplies AC input AI to each part of this plasma display device 100A, and a power supply unit 8 that detects the power-on of the power supply unit 8 and detects the initialization command being inputted during the corresponding period. A display prohibition signal output circuit 3 that outputs a medium display prohibition signal PHB, a video RAM circuit 4 that temporarily stores image information, and data information for a character generator (CG: not shown) included in the display controller 2. It includes a CGROM circuit 5 for storage, a drive signal conversion circuit 6 for converting a drive signal ACT into a display control signal, and an XY matrix type plasma display unit 12 for displaying an image based on the display control signal.

The X-Y matrix type plasma display unit 12 also includes a plasma display panel (hereinafter referred to as a PDP panel) 11 that displays images by plasma discharge light emission, and a Y electrode (not shown) on the PDP panel 11. Y driver 9 that drives the X electrode (not shown) on the PDP panel 11, and X driver 1 that drives the X electrode (not shown) on the PDP panel 11
0, and a PDP controller 7 that controls the Y driver 9 and the X driver 10 based on the display control signal.

Here, external inputs include data line DT, selection signal SL, address line AD, and R/W signal R.
W, there is a reset signal RST. In addition, as display control signals, horizontal synchronization signal HSYNC, vertical synchronization signal VSY
There are NC, clock signal CLK, and data signal DA. Here, the XY matrix type plasma display unit 12 corresponds to the XY matrix type plasma display unit 105. The display controller 2, video RAM circuit 4, CGROM circuit 5, and drive signal conversion circuit 6 constitute a display control means 104.

Next, FIG. 3 shows a more detailed configuration of the display inhibit signal output circuit 3 in FIG. 2. This display prohibition signal output circuit 3 includes a command code setting circuit 3 as shown in the figure.
1, comparison circuit 32, flip-flop circuit 33, AND
It has a circuit 34 and a power-on reset IC 35. In FIG. 3, a command code setting circuit 31 is a setting circuit including a setting switch, a setting terminal, etc. for setting a code corresponding to the code of an initialization command such as a parameter set command from a host computer. The comparison circuit 32 is a Magnitude Comparator for comparing the command code from the host computer and the command code of the command code setting circuit 31.
This is a comparison circuit such as or. The flip-flop circuit 33 is a flip-flop circuit that outputs a display prohibition signal PHB when it detects that an initialization command has been input from the host computer. The AND circuit 34 connects the plasma display device 10 from the host computer.
This is an AND circuit that detects that a command is input to 0A. The power-on reset IC 35 is a power-on reset IC that detects that the power of the plasma display device 100A is turned on. Next, the operation of this display inhibit signal output circuit 3 will be explained using FIGS. 3 and 4. As shown in FIG. 4, when the plasma display device 100A is powered on, the output PW of the power-on reset IC 35 detects the voltage of VCC,
Maintain “L” level until the specified value is reached. In this case, V.C.
The output of PW is unstable until C reaches about 2.0V. When the specified value is reached, the power-on reset IC 35 outputs the "H" level PW, but it is externally set to output the "L" level for a certain period of time TD even after reaching the specified value. Ru.

By inputting the output PW of this power-on reset IC 35 to the CLR terminal of the flip-flop circuit 33, the output PHB(
The display inhibit signal) is cleared immediately after the power is turned on and goes to "L" level. Then, this display prohibition signal PHB is transmitted to the PDP.
By inputting it to the RST terminal of the controller 7, the outputs of the Y driver 9 and the X driver 10 are set to a high impedance state while the display prohibition signal PHB is at "L" level.
Display on the PDP panel 11 is prohibited. Even if a display command, etc. is input from the host computer in this state (
a) Since the parameter set command and the command code do not match, the output CP of the comparison circuit 32 is “H” (A=
B), the output PHB of the flip-flop circuit 33 remains at the "L" level, and the display inhibition is not released.

Next, when a parameter set command is input from the host computer (b), the command codes match and the output of the comparison circuit 32 becomes "H" (A=B), so the flip-flop is activated at the rising edge. The output PHB of the pull circuit 33 changes from "L" to "H", and the display inhibition is canceled. Even if a display command is subsequently entered (
c) “H” of the output PHB of the flip-flop circuit 33
Since the level does not change, the display will not be inhibited until the power is turned on again.

In this way, the period TPH in FIG.
During this period, there is a display prohibition period in which display on the XY matrix plasma display unit 105 is prohibited. Here, the power-on reset IC 35 corresponds to the power-on detection means 101. In addition, the command code setting circuit 31
, the comparison circuit 32 and the AND circuit 34 constitute a command detection means 102. The flip-flop circuit 33 corresponds to the display inhibiting means 103.

[0015]

[Effects of the Invention] As explained above, according to the present invention,
The period from when the power is turned on to the plasma display device until the scan output cycle from the display controller is made constant by inputting an initialization command from the host computer, and the processing of other commands such as display commands without accidentally executing the initialization command. Even when this is done, it is possible to prevent abnormal display from occurring, and this has the effect of contributing to improving the performance of the plasma display device.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the present invention.

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

FIG. 3 is a diagram showing the configuration of a display prohibition signal output circuit in an embodiment of the present invention.

FIG. 4 is a timing chart showing the operation of an embodiment of the present invention.

[Explanation of symbols]

1...Interface buffer circuit 2...Display controller 3...Display inhibit signal output circuit 4...Video RAM circuit 5...CGROM circuit 6...Drive signal conversion circuit 7...PDP controller 8...Power supply unit 9...Y driver 10...X driver 11...PDP Panel 12...X-Y matrix type plasma display unit 31...Command code setting circuit 32...Comparison circuit 33...Flip-flop circuit 34...AND circuit 35...Power-on reset IC 100, 100A...Plasma display device 101...
Power-on detection means 102...Command detection means 103...Display prohibition means 104...Display control means 105...X-Y matrix type plasma display unit ACT...Drive signal AD...Address line AI...AC input CLK...Clock signal CP...Comparison output DA …Data signal DT…Data line EB…AND circuit output HSYNC…Horizontal synchronization signal PHB…Display prohibition signal PW…Power-on reset IC output RST…Reset signal RW…R/W signal SCD…Command detection signal SGC…Display control signal SIN …External input SPW…Power on signal SL…Selection signal TD…Certain period TPH…Display inhibit period VCC…Power supply voltage VSYNC…Vertical synchronization signal

Claims (1)

[Claims] 1. An X-Y matrix plasma display unit (105) that displays an image by plasma discharge light emission based on a display control signal (SGC), and the display control signal based on an external input (SIN) related to image display. In a plasma display device equipped with a display control means (104) that outputs a signal (SGC), a power-on detection means (101) that detects power-on to the plasma display device and outputs a power-on signal (SPW).
and the initialization command (CPS) from the input (SIN).
) and outputs a command detection signal (SCD);
SPW) output until the command detection signal (SCD) is output, the plasma display unit (10
5) display prohibition means (103) for prohibiting the display operation;
A plasma display device comprising: