Epson Research and Development Page 21
Vancouver Design Center
Programming Notes and Examples S1D13504
Issue Date: 01/02/01 X19A-G-002-07
2 bpp Gray Shade
In 2 bpp gray shade mode, the 16 LUT entries are divided into four separate banks, each having four
entries:
4 bpp Gray Shade
In 4 bpp gray shade mode, the pixel value indexes into one of 16 LUT entries. The LUT bank bits
are ignored in this mode. The recommendation for this mode is to program the register values to data
values equalling the register number (i.e. G[0] = 0, G[1]=1, G[2]=2, ... G[F]=0Fh).
8 bpp Gray Shade
When the S1D13504 is configured for 8 bpp gray shade mode, bits [7:5] are ignored, bits [4:2]
represent the green LUT index, and bits [1:0] are ignored. Only 3 bits of the 8 that actually represent
any shade value, therefore the maximum gray shade combination is 8 shades. If this limitation is
deemed appropriate for your application, it is recommended that the LUTs are programmed
according to the following format: Red and Blue LUT entries are not important, Green LUT indexes
0-7 should be programmed 0-F as in the table below:
This recommended LUT assumes that you are using only bank 0.
Table 3-14: Recommended LUT Values for 2 bpp Gray Shades
Index
(hex)
Look-Up Table
Data
(hex)
00 00
01 05
02 0A
03 0F
Table 3-15: Recommended LUT Values for 8 bpp Gray Shade
LUT Address Green LUT Data
00 00
01 02
02 04
03 06
04 08
05 0A
06 0C
07 0F