AMD Geode LX 800@0.9W - Manual (Page 348)

348 AMD Geode™ LX Processors Data Book
Display Controller Register Descriptions 33234H
6.6.12.2 DC Color Key Mask (DC_CLR_KEY_MASK)
6.6.12.3 DC Color Key Horizontal Position (DC_CLR_KEY_X)
Settings written to this register do not take effect until the start of the following frame or interlaced field.
6.6.12.4 DC Color Key Vertical Position (DC_CLR_KEY_Y)
Settings written to this register do not take effect until the start of the following frame or interlaced field.
DC Memory Offset 0BCh
Type
R/W
Reset Value 00xxxxxxh
DC_CLR_KEY_MASK Register Map
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RSVD CLR_KEY_MASK
DC_CLR_KEY_MASK Bit Descriptions
Bit Name Description
31:24 RSVD Reserved. Set to 0.
23:0 CLR_KEY_
MASK Color Key Mask. This field is ANDed with both the pixel and the color key value (in
DC_CLR_KEY, DC Memory Offset 0B8h[23:0]) before comparing the values. This allows
the value of some bits to be ignored when performing the match.
DC Memory Offset 0C0h
Type
R/W
Reset Value 00000000h
DC_CLR_KEY_X Register Map
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RSVD CLR_KEY_X_END RSVD CLR_KEY_X_START
DC_CLR_KEY_X Bit Descriptions
Bit Name Description
31:27 RSVD Reserved. Set to 0.
26:16 CLR_KEY_X_
END Color Key Horizontal End. This field indicates the horizontal end position of the color
key region minus 1.This represents the first pixel past the end of the color key region.
This field is 0-based; the upper left pixel of the screen is represented by (0,0).
15:11 RSVD Reserved. Set to 0.
10:0 CLR_KEY_X_
START Color Key Horizontal Start. This field represents the horizontal start position of the color
key region minus 1. This represents the first pixel within the color key region.
DC Memory Offset 0C4h
Type
R/W
Reset Value 00000000h
DC_CLR_KEY_Y Register Map
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RSVD CLR_KEY_Y_END RSVD CLR_KEY_Y_START