
ViiiPeRiPheRaLMoDuLes6(LCD):LCDContRoLLeR(LCDC)
s1C33L17teChniCaLManuaL
ePson
Viii-1-23
VIII
LCDC
Color-modelook-uptables
In color mode, the LCD controller uses the red (R), green (G), and blue (B) look-up tables. Each color ele-
ment is represented by 6-bit data. RGB = 000000 is black, RGB = 3F0000 is red, RGB = 002000 is 50%
luminance green, RGB = 3F003F is magenta, RGB = 3F3F3F is white, and so on. In this way, colors are
determined by the proportions of the three color elements. If the luminance of each color element is represented
by 6 bits, then we obtain 64
× 64 × 64 = 256K colors. Of these, select as many pieces of color data as can be
used for the available display mode (256 or 4K colors), and write them to the valid entries of the look-up tables
before using the LCD panel.
The differences in configurations between display modes are shown below.
(1)8-bpp(256-color)mode
One pixel is represented by 8 bits, displayed in 256 colors. In this mode, 256 discrete combinations are config-
ured using 8 entries in each of the red and green look-up tables, and 4 entries in the blue look-up table. Bits 7
–5 in 8 bits of pixel data are used as an index to the red look-up table, while bits 4–2 and bits 1–0 are used as
indices to the green and blue look-up tables, respectively.
6-bitRdataforpixeldata0x0
6-bitRdataforpixeldata0x1
6-bitRdataforpixeldata0x2
6-bitRdataforpixeldata0x7
6-bitRdataforpixeldata0x3
Redlook-uptable
Index
0
1
2
3
6-bitRdataforpixeldata0x4
4
6-bitRdataforpixeldata0x5
5
6-bitRdataforpixeldata0x6
6
7
Unused
8
:
15
000
001
010
011
100
101
110
111
3-bitRpixeldata
fromdisplaybuffer
6-bitRdisplaydata
R[2:0]
R[2,1,0,2,1,0]
LUTPASS
6-bitGdataforpixeldata0x0
6-bitGdataforpixeldata0x1
6-bitGdataforpixeldata0x2
6-bitGdataforpixeldata0x7
6-bitGdataforpixeldata0x3
Greenlook-uptable
Index
0
1
2
3
6-bitGdataforpixeldata0x4
4
6-bitGdataforpixeldata0x5
5
6-bitGdataforpixeldata0x6
6
7
Unused
8
:
15
000
001
010
011
100
101
110
111
3-bitGpixeldata
fromdisplaybuffer
6-bitGdisplaydata
G[2:0]
G[2,1,0,2,1,0]
LUTPASS
6-bitBdataforpixeldata0x0
6-bitBdataforpixeldata0x1
6-bitBdataforpixeldata0x2
6-bitBdataforpixeldata0x3
Redlook-uptable
Index
12
13
14
15
Unused
0
:
11
00
01
10
11
2-bitBpixeldata
fromdisplaybuffer
6-bitRdisplaydata
B[1:0]
B[1,0,1,0,1,0]
LUTPASS
FigureVIII.1.5.5.5Look-upTablein8-bpp(256-Color)Mode