Mask color select when PC-9800
6.3 Mask color select when PC-9800
This function selects the color of the mask section at the top and bottom of the screen when PC-9800 is input with
input function of RGB 1 or RGB 2.
The display is factory-set to black.
6.3.2 Setting method
This function can be set only through RS232C commands.
Activate RS232C adjustment mode and
Send a <MKB> command to set the black mask section.
Send a <MKG> command to set the gray mask section.
Depending on the input signal, the rate of phosphor deterioration in the masked section may differ from that in the
unmasked section. For example, a display with mask section color set to BLACK that receives PC-9800 signals and
rarely displays a 480-full-line display will suffer no phosphor deterioration in the top and bottom mask sections and
demonstrate better luminance and white-balance for the full 480-line display than for other 400-line displays.
6.4 Pseudo contour
When input function is RGB 1 or RGB 2, and a gradation image (such as human face and skin) moves at a speed, the
"stripe-like shadow" may appear in that image. This "stripe-like shadow" is known as the "pseudo contour".
This phenomenon is an illusion of human eyes attributable to the gradation expression method peculiar to the plasma
display. This phenomenon does not appear in stills picture images.
The problem of this noise (pseudo contour) has been solved by using PIONEER's unique driving system, and achieved
high picture quality (particularly, for animation).Note that this technology is effective, only when operation is for NTSC
(interlace signal) and computer images (no-interlace signal), with MP mode ON. Therefore, when the following signals
are inputted, this phenomenon may appears when MP mode is OFF:
• VGA animation signal (when a high speed game software and video CD play on PC.
• NTSC double scanning signal (using double raster, etc.)
is input / Pseudo contour
Images are displayed over 400 lines.