Lucent Technologies MN10285K - Manual (Page 199)

On-Screen Display
Controlling the Shuttering Effect
Panasonic Semiconductor Development Company MN102H75K/F75K/85K/F85K LSI User Manual
198
Panasonic
7.13.3 Controlling Shuttering Effects
Through register settings, you can independently control shuttering for text, text
background, graphics, and color background. You can also output blanks to the
shuttered area.
You cannot shutter the cursor layer.
Table 7-13 shows the register settings required for these effects. There are three
types of shuttering —shuttering of text, text background, and graphics, shuttering
of the color background, and shutter blanking. The sections below describe how
to control each of these.
■ To shutter text-layer characters, text-layer background, and graphics layer:
Do not allow the horizontal shut-
tering boundaries to overlap any
italicized portion of a closed-
caption display. This distorts the
italicized characters.
Text
Set the text shutter control bit, CCSHT, of the shutter control register, SHTC
(x’007F28’) to 1.
Text background
Set the text background shutter control bit, BCSHT, of SHTC to 1.
Graphics
Set the text background shutter control bit, GSHT, of SHTC to 1.
Figure 7-33 shows three setup examples of text-layer shuttering.
Table 7-14 Bit Settings for Controlling Shuttering Effects
Function Bit Name Description
Text shuttering CCSHT 0: Shutter text-layer characters
1: Don’t shutter text-layer characters
Text background
shuttering
BCSHT 0: Shutter text-layer background
1: Don’t shutter text-layer background
Graphics shuttering GSHT 0: Shutter graphics layer
1: Don’t shutter graphics layer
Color background
shuttering
COLBSHT 0: Shutter color background
1: Don’t shutter color background
Shutter blanking SHTBLK 0: Don’t output blanks to the shuttered area
1: Output blanks to the shuttered area