Samsung S3C6400X User Manual page 383

S3C6400X RISC MICROPROCESSOR
BLENDING DIAGRAM/DETAILS
Display controller can blend 5 Layer for only one pixel at the same time. The Blending factor, alpha value is
controlled by ALPHA0_R,ALPHA0_G,ALPHA0_B, ALPHA1_R,ALPHA1_G,ALPHA1_B register, which are
implemented for each window layer and color(R,G,B). The illustration below is described as the example of the R
(Red) output using ALPHA_R value of each window. All windows have two kinds of alpha blending value. One is
alpha value for transparency enable (AEN value ==1), the other is alpha value for transparency disable (AEN
value == 0). If WINEN_F is enabled and BLD_PIX is enabled then AR will be selected by applying the below
equation.
AR = ( Pixel(R)'s AEN value == 1'b1) ? Reg( ALPHA1_R ) : Reg( ALPHA0_R );
AG = ( Pixel(G)'s AEN value == 1'b1) ? Reg( ALPHA1_G ) : Reg( ALPHA0_G );
AB = ( Pixel(B)'s AEN value == 1'b1) ? Reg( ALPHA1_B ) : Reg( ALPHA0_B );
(where, BLD_ PIX == 1)
If WINEN_F is enabled and BLD_PIX is disabled then AR will be ALPHA0_R only. In this case blending factor AR
is fixed by ALPHA0_R, not using the AEN bit information anymore.
Win0(R) x (1- AR1)
+
x (1-AR2)
Win1(R) x AR1
Win2(R) x AR2
+
x (1-AR3)
+
x (1-AR4)
Figure 14-4. Blending diagram
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
Win3(R) x AR3
Win4(R) x AR4
+
OUTPUT(R)
DISPLAY CONTROLLER
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