Epson S1D13505 Technical Manual page 181

Epson Research and Development
Vancouver Design Center
Programming Notes and Examples
Issue Date: 01/02/05
4 bpp gray shade
The 4 bpp gray shade mode uses the first 16 LUT elements. The remaining indices of the
LUT are unused.
Table 4-8: Suggested LUT Values for 4 Bpp Gray Shade
Index
00
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
...
FF
8 bpp gray shade
When 8 bpp gray shade mode is selected the gray shade intensity is determined by the green
LUT value. The green portion of the LUT has 16 possible intensities. There is no color
advantage to selecting 8 bpp mode over 4 bpp mode; however, hardware rotate can be only
used in 8 and 16 bpp modes.
15 bpp gray shade
The Look-Up Table is bypassed at this color depth, hence programming the LUT is not
necessary.
As with 8 bpp there are limitations to the colors which can be displayed. In this mode the
four most significant bits of green are used to set the absolute intensity of the image. Four
bits of green resolves to 16 colors. Now however, each pixel requires two bytes.
Red Green Blue
00 00
10 10
20 20
30 30
40 40
50 50
60 60
70 70
80 80
90 90
A0 A0 A0
B0 B0 B0
C0 C0 C0
D0 D0 D0
E0 E0
F0 F0 F0
00 00
00 00
00 00
Required to match CRT to panel
Unused entries
00
10
20
30
40
50
60
70
80
90
E
00
00
00
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S1D13505
X23A-G-003-07