SMAS Memory Map
Clipping
Clipping X Size
Clipping Y Size
Counter
Direction
DMA
Empty
Flag
Frequency
Generator
Graphics
Hardware Mirror
HDMA
Index
Level
Level Data
Level Data (Objects)
Level Data (Sprite)
Map16
Map16 Tile
Map16 Tilemap
Miscellaneous
Music
OAM Tile Number
OAM Tile Properties
OAM Tile Size
OAM Tile X Position
OAM Tile Y Position
OAM Tilemap
Objects
Overworld
Palette
Player
Player Action
Pointers
Position
Powerup
Routine
Score
Screen
Shooter
Sound Effect
SPC-700
Speed
Sprite Number
Sprites
Stack
Stripe Image
Stripe Image (Text)
Timer
VRAM
VRAM Tilemap
VRAM Tilemap (Text)
World
X Position
X Speed
Y Position
Y Speed
Clipping
Clipping X Size
Clipping Y Size
Counter
Direction
DMA
Empty
Flag
Frequency
Generator
Graphics
Hardware Mirror
HDMA
Index
Level
Level Data
Level Data (Objects)
Level Data (Sprite)
Map16
Map16 Tile
Map16 Tilemap
Miscellaneous
Music
OAM Tile Number
OAM Tile Properties
OAM Tile Size
OAM Tile X Position
OAM Tile Y Position
OAM Tilemap
Objects
Overworld
Palette
Player
Player Action
Pointers
Position
Powerup
Routine
Score
Screen
Shooter
Sound Effect
SPC-700
Speed
Sprite Number
Sprites
Stack
Stripe Image
Stripe Image (Text)
Timer
VRAM
VRAM Tilemap
VRAM Tilemap (Text)
World
X Position
X Speed
Y Position
Y Speed
World
Extra Lives
Flag
Level Progress
World Progress
Miscellaneous
Empty
SNES Register (PPU)
SNES Register (APU)
SNES Register (Hardware)
SNES Register (Controller)
SNES Register (DMA)
Regs Address
Length
Type
Description
Details
$210D
4 bytes
SNES Register (PPU)
w w + + + - BG1HOFS - BG1 Horizontal Scroll w w + + + - M7HOFS - Mode 7 BG Horizontal Scroll w w + + + - BG1VOFS - BG1 Vertical Scroll w w + + + - M7VOFS - Mode 7 BG Vertical Scroll ------xx xxxxxxxx ---mmmmm mmmmmmmm x = The BG offset, 10 bits. m = The Mode 7 BG offset, 13 bits two's-complement signed. These are actually two registers in one (or would that be "4 registers in 2"?). Anyway, writing $210d will write both BG1HOFS which works exactly like the rest of the BGnxOFS registers below ($210f-$2114), and M7HOFS which works with the M7* registers ($211b-$2120) instead. Modes 0-6 use BG1xOFS and ignore M7xOFS, while Mode 7 uses M7xOFS and ignores BG1HOFS. See the appropriate sections below for details, and note the different formulas for BG1HOFS versus M7HOFS.