Z90251 Datasheet, PDF (49/97 Pages) Zilog, Inc. – eZVision 200 Television Controllers with OSD

Z90255 ROM and Z90251 OTP
32 KB Television Controller with OSD
41
Table 22 Display Attribute Register 03h: Bank A (DISP_ATTR)
Bit
7
6
5
4
3
2
1
0
R/W
R/W R/W R/W
Reset
0
0
0
Note: R = Read W = Write X = Indeterminate
R/W
0
R/W
0
R/W
0
R/W R/W
0
0
Bit/
Field
Bit
Position R/W
Value Description
Character Display
7
R/W
0 Disable Character Display
1 Enable Character Display
Master
6
Background Enable
R/W
0 No Master Background
1 Incoming video is swapped with
the background color
Fringe Effect Enable 5
R/W
0 Fringe Effect is Disabled
1 Fringe Effect is Enabled
Smoothing Effect
4
Enable
R/W
0 Smoothing enabled
1 Smoothing disabled
RGB Polarity
3
R/W
0 Positive
1 Negative
Red Master
2
R/W
Background
See Table 21
Green Master
1
R/W
Background
See Table 21
Blue Master
0
R/W
Background
See Table 21
Bit 7, Display Enable, disables or enables using foreground and background
color, and therefore character display. When this bit is set to 0, effective space
characters are sourced from the video RAM. Background On/Off and row
background color are programmed independently. When bit 7 is set to 1, the
actual video RAM characters are displayed.
Bit 6, Master Background Enable, disables or enables using a background color
for the entire screen instead of the broadcast signal. If this bit is set to 1, the
incoming video signal blanks and the screen background displays color according
to the background color bits. The color is specified in bits 2, 1, 0. If bit 6 is set to
0, the incoming video signal is displayed.
PS001301-0800