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Output color
HWC Index memory
array
2bpp mode
bit0
bit7
HWC palette table
3
Color0
0
R0
G0
B0
Color1
1
R1
G1
B1
Color254

254 R254 G254 B254
Color255

255 R255 G255 B255
2
0
2
2
R2
G2
B2
0
R0
G0
B0
2
R2
G2
B2
3
R3
G3
B3
2
R2
G2
B2
1
3
2
2
2
R2
G2
B2
3
3
0
1
3
R3
G3
B3
1
R1
G1
B1
1
R1
G1
B1
0
R0
G0
B0
3
R3
G3
B3
3
R3
G3
B3
Hardware cursor index memory
& palette
28.5.39. Palette Mode
Offset:
Pipe0:0x5000-0x53FF
Pipe1:0x5400-0x57FF
Pipe palette color table SRAM block
Bit
Read/Wr
ite
Default/
Hex
Description
31:24
R/W
UDF
Alpha value
23:16
R/W
UDF
Red value
15:08
R/W
UDF
Green value
07:00
R/W
UDF
Blue value
In this mode, RAM array is used for palette lookup table; each pixel in the layer frame buffer is treated
as an index into the RAM array to select the actual color.
The following figure shows the RAM array used for palette lookup and the corresponding colors
output.
On chip SRAM array
Inputting external
frame buffer data
(8bpp)
5
38
133
0
1
28
n
254
255
R0
G0
B0
R1
G1
B1
Rn
Gn
Bn
Output color
5
38
133
28
R5
G5
B5
R38
G38
B38
R133 G133 B133
R28
G28
B28
R254 G254 B254
R255 G255 B255
On chip SRAM for palette lookup
A13 User Manual V1.3
Copyright © 2013 Allwinner Technology. All Rights Reserved.
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