Nintendo DMG-01 - Game Boy Console Manual page 127

TM
Game Boy CPU Manual
8. Set System Color Palette Data ($0b)
9. Enable/Disable Attraction Mode ($0c)
10. Speed Function ($0d)
11. SGB Function ($0e)
12. Super NES WRAM Transfer 1 ($0f)
13. Super NES WRAM Transfer 2 ($10)
14. Controller 2 Request (#11) ($00) - Request 1 play
15. Controller 2 Request (#11) ($01) - Request 2 play
Is used to determine if system is SGB or regular GB.
16. Set Program Counter ($12)
17. CharSet Transfer ($13)
(%00000xyy) (x=Char Type:0=BG,1=OBJ
Range:0=00-7f,1=80-ff)
The tiles that are downloaded to the SNES for the
border are regular GB tiles that have been modified for
extra colors. Every tile consists of 32 bytes. The
format is:
16 bytes - Standard 4 color GB character set
16 bytes - Extended color information
The same way GB uses two bytes to convey 8 pixels
and the 4 colors for each pixel, the extended color
by DP
4.5. Commands
y=CharSet
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