sed1355 ETC-unknow, sed1355 Datasheet - Page 173

• Manufacturer Part Number: sed1355
• Description: Sed1355 Embedded Ramdac Lcd/crt Controller
• Manufacturer: ETC-unknow

Epson Research and Development
Vancouver Design Center
Color Modes
Programming Notes and Examples
Issue Date: 99/04/27
In color display modes, depending on the color depth, 2 through 256 index entries are used. The
selection of which entries are used is automatic.
1 bpp color
When the SED1355 is configured for 1 bpp color mode, the LUT is limited to the first two entries.
The two LUT entries can be any two RGB values but are typically set to black-and-white.
Each byte in the display buffer contains 8 bits, each pertaining to adjacent pixels. A bit value of ’0’
results in the LUT 0 index value being displayed. A bit value of ’1’ results in the LUT 1 index value
being displayed.
The following table shows the recommended values for obtaining a black-and-white mode while in
1 bpp on a color panel.
2 bpp color
When the SED1355 is configured for 2 bpp color mode only the first 4 entries of the LUT are used.
These four entries can be set to any desired values.
Each byte in the display buffer contains 4 adjacent pixels. Each pair of bits in the byte are used as
an index into the LUT. The following table shows example values for 2 bpp color mode.
Table 4-2: Recommended LUT Values for 1 Bpp Color Mode
Table 4-3: Example LUT Values for 2 Bpp Color Mode
Index
Index
FF
00
01
02
FF
00
01
02
03
04
...
...
= Indicates unused entries in the LUT
= Indicates unused entries in the LUT
Red
Red
F0
A0
00
00
00
00
00
70
F0
00
00
00
Green
Green
00
F0
00
00
00
00
70
A0
F0
00
00
00
Blue
Blue
F0
00
70
A0
F0
00
00
00
00
00
00
00
X23A-G-003-05
SED1355
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