Samsung S5PC110 Manual page 1595

S5PC110_UM
MIXER_GRAPHIC0_CFG
EG_COLOR_FORMAT0
REG_ALPHA_WIN0
NOTE: All the changes of this register are valid on a vertical sync signal of next frame.
Bit
[11:8] Graphic layer0 color format.
0 = Reserved
1 = Reserved
2 = Reserved
3 = Reserved
4 = RGB 565
5 = ARGB 1555
6 = ARGB 4444
7 = ARGB 8888
8 = Reserved
9 = Reserved
A = Reserved
B = Reserved
C = Reserved
D = Reserved
E = Reserved
F = Reserved
[7:0] Graphic layer0 and lower layer blending factor. This factor
is used all over the pixels in the graphic and lower layer to
blend with.
A blending factor(α) is as follows depending on the a
layer blending factor and a pixel blending factor values:
α * graphic_layer_pixel_value + (1 – α) *
lower_layer_pixel_value
See
Table 9-1.
If REG_ALPHA_WIN0 is 0, blending_factor_layer is 0.
If REG_ALPHA_WIN0 is not 0, blending_factor_layer =
(REG_ALPHA_WIN + 1) / 256.
If A(blending factor of each pixel) is 0,
blending_factor_each_pixel is 0
If A(blending factor of each pixel) is not 0,
blending_factor_each_pixel = (A + 1) / 256.
The pixel blending factors comes from the pixel in direct
modes except the direct 16bpp 565 format.
Description
9 8BMIXER
Initial State
0
0
9-15