PXD10RM Datasheet, PDF (417/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

Table 12-62 defines how the settings of the BB and AB bit fields affect the pixels in the layer; RGB modes
are 1 bpp, 2 bpp, 4 bpp, 8 bpp, RGB565, and RGB888; ARGB modes are ARGB1555, ARGB4444, and
ARGB8888.
Table 12-62. Blend options for BB and AB configurations
Case
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
BB
AB[1:0] Format
Function
0
00
RGB No blending, underlying pixels are obscured
1
00
RGB Selected pixels are completely removed
0
01
RGB The value in TRANS becomes the alpha channel of all pixels
on the layer
1
01
RGB The value in TRANS becomes the alpha channel of the
selected pixels on the layer
0
10
RGB Same as case 3
1
10
RGB Selected pixels are completely removed and the value in
TRANS becomes the alpha channel of the non-selected pixels
on the layer
0
11
RGB Reserved
1
11
RGB Reserved
0
00
ARGB No blending, pixel alpha is ignored and underlying pixels are
obscured
1
00
ARGB Selected pixels are completely removed, pixel alpha is ignored
0
01
ARGB Pixel alpha is used to blend layer with underlying pixels. Value
in TRANS is ignored.
1
01
ARGB Uses the pixel alpha of the selected pixels only to blend layer
with underlying pixels. Value in TRANS is ignored.
0
10
ARGB The value in TRANS is multiplied with the pixel alpha value and
the resultant alpha is used to blend all the pixels
1
10
ARGB Selected pixels are completely removed, the value in TRANS
is multiplied with the pixel alpha value and the resultant alpha
is used to blend the non-selected pixels on the layer
0
11
ARGB Reserved
1
11
ARGB Reserved
Figure 12-61 to Figure 12-69 illustrate the effect of the cases identified in Table 12-62. In all cases there
is a single active layer and a white background color.
Freescale Semiconductor
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
12-85