EAGLE
PRELIMINARY
Ver 1.3
Register Description
3.15.3 OSD Control Register (OSDCON)
Address : FFE0 4C00h
Bit
31 : 6
5
4
3
R/W
R
Description
Default Value
Reserved
OSD Enable
-
R/W
R/W
R/W
R/W
R/W
0b
0b
0b
0b
00b
CPU Palette RAM Access Enable
Second Visible Area Enable
First Visible Area Enable
Select the BPP (Bits Per Pixel) mode for OSD
00: 4 BPP
2
1: 0
01: 8 BPP
10: 16BPP
The OSD window which displays the OSD image is in the shape of a rectangle and user may configure this rectangular
region.
3.15.4 OSD Transparent Color Register (OSDTC)
Address : FFE0 4C04h
Bit
R/W
R
R/W
R/W
R/W
Description
Default Value
31 : 24
23 : 16
15 : 8
7 : 0
Reserved
-
Red value
Green value
Blue value
00h
00h
00h
Transparent Color register allows user to make a specific OSD image color transparent.
3.15.5 Alpha Blending Control Register (OSDACON)
Address : FFE0 4C08h
Bit
31 : 26
25
R/W
R
R/W
Description
Default Value
Reserved
-
0b
This bit determines the number of alpha blending color
0 : 4 Alpha blending colors as defined in OSD Alpha Blending Color
register
1 : Support all colors of Alpha Blending Color
Alpha Blending enable / disable
0 : disable
24
R/W
0b
1 : enable
23 : 16
15 : 8
7 : 0
R/W
R/W
R/W
Alpha Blending ratio of Red color
Alpha Blending ratio of Green color
Alpha Blending Blue ratio of Blue color
00h
00h
00h
Alpha blending is an image processing operation that combines OSD image and CRTC image.
Display_image = A*OSD_image + (1 – A)*CRTC_image
A : alpha blending ratio
Beijing Peak Microtech Co.Ltd.
CONFIDENTIAL
142
ETC [ ETC ]
