Nintendo DMG-01 - Game Boy Console Manual page 132

4.5. Commands
$02 = Mask so that all color codes in SGB
color palette are black.
$03 = Mask so that all color codes in SBG
color palette are white.
22. Super NES OBJ Mode ($18)
23. SNES Color Palette Info
The Nintendo Super Famicom is capable of displaying
256 colors from a palette of 32,768. These 256 colors
are split into 16 palettes of 16 colors each. Only 8 of
these palettes are accessible by the SGB.
Color data is made up of 3 components (Red,Green,Blue)
each of 5 bits (The Amiga uses exactly the same system,
but only using 4 bits per component).
Examples:
00000 10111 11100
11111 00000 00000 = $7C00 (Bright Blue)
00000 11111 00000 = $03E0 (Bright Green)
00000 00000 11111 = $001F (Bright Red)
00000 00000 00000 = $0000 (Black)
11111 11111 11111 = $7FFF (White)
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