Nintendo DMG-01 - Game Boy Console Manual page 128

TM
4.5. Commands Game Boy CPU Manual
info uses the same technique for determining extended
colors. This tells the SNES which color palette to
use to display each pixel. This allows a total of 16
colors per tile. Since SGB borders support up to 64
colors, access to the other colors are achieved by
changing the Major palette number in the picture
transfer tile map.
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