AMD Geode™ LX Processors Data Book 435
Video Processor Register Descriptions 33234H
17:16 A1P Alpha Window 1 Priority. Indicates the priority of alpha window 1. A higher number indi-
cates a higher priority. Priority is used to determine display order for overlapping alpha
windows.
This field is reset by hardware to 00.
15 ALPHA_DRGB Enable Alpha on DRGB[31:24]. The source of the alpha value is the upper 8 bits [31:24]
of the graphics input bus. When this bit is set, the upper 8 bits of the graphics input bus is
passed through to the upper 8 bits [31:24] of the DRGB output bus. If bit 14 is also set,
the actual video blended alpha value replaces the graphics alpha value when inside an
alpha window.
00: DRGB[31:24] are not driven.
01: DRGB[31:24] are not driven.
10: DRGB[31:24] contain contents of graphics input bus [31:24].
11: DRGB[31:24] contain contents of graphics input bus [31:24] when NOT inside any
alpha window; inside any alpha window, DRGB[31:24] contains actual video alpha
value.
14 VID_ALPHA_EN Enable Video Alpha value onto DRGB[31:24]. When inside an alpha window, drive the
video alpha value (graphics per-pixel alpha value multiplied by the multiplier) onto bits
[31:24] of the DRGB output bus.
00: DRGB[31:24] are not driven.
01: DRGB[31:24] are not driven.
10: DRGB[31:24] contain contents of graphics input bus [31:24].
11: DRGB[31:24] contain contents of graphics input bus [31:24] when NOT inside any
alpha window; inside any alpha window, DRGB[31:24] contains actual video alpha
value.
13 GV_SEL Graphics Video Select. Selects input video format.
0: YUV format.
1: RGB format.
If this bit is set to 1, bit EN_420 (VP Memory Offset 000h[28]) must be set to 0.
12 CSC_VOP Color Space Converter for VOP. Determines whether or not the output from the blender
is passed through the Color Space Converter (CSC) before entering the VOP.
0: Disable. The output of the blender is sent “as is” to the mixer/blender.
1: Enable. The output of the blender is passed through the CSC (for RGB to YUV conver-
sion).
11 CSC_GFX Color Space Converter for Graphics. Determines whether or not the graphics stream
is passed through the Color Space Converter (CSC).
0: Disable. The graphics stream is sent “as is” to the mixer/blender.
1: Enable. The graphics stream is passed through the CSC (for RGB to YUV conver-
sion).
10 CSC_VIDEO Color Space Converter for Video. Determines whether or not the video stream from the
video module is passed through the Color Space Converter (CSC).
0: Disable. The video stream is sent “as is” to the video mixer/blender.
1: Enable. The video stream is passed through the CSC (for YUV to RGB conversion).
9 HDSD High Definition/Standard Definition CSC. Determines which algorithm to use for
graphics color space conversion from RGB to YUV.
0: Standard Definition.
1: High Definition.
VDE Bit Descriptions (Continued)
Bit Name Description