Memory map

Start Address	End Address	Physical Address	Size	Description
0x80000000	0x817FFFFF	0x00000000	24 MB	MEM1 Memory (Cached)
0xC0000000	0xC17FFFFF	0x00000000	24 MB	MEM1 Memory (Uncached)
0x90000000	0x93FFFFFF	0x10000000	64 MB	MEM2 Memory (Cached)
0xD0000000	0xD3FFFFFF	0x10000000	64 MB	MEM2 Memory (Uncached)
0xCD000000	0xCD008000	0x0D000000		Hollywood Registers (shared with Starlet)

The GameCube has one 24MB bank of 1T SRAM that is used for all code and data, spread across two external chips; there is also a chip containing 16MB of ARAM, which could be used for storing data.

The Wii moves all 24MB of 1T-SRAM (referred to as MEM1) inside the Hollywood package, and adds an additional 64MB of GDDR3 RAM (MEM2). During normal operation, IOS reserves the upper 12-16MB of MEM2 for its own use; the rest can freely be used for code or data by running PPC code. MEM1 is slightly faster than MEM2.

The IOS Heap range is usually 0x933E0000 – 0x93400000, as shown in registers 0x80003130(Start), 0x80003134(End). Pointers in this area are often passed back and forth between IOS and code running on Broadway. The top of MEM2 memory is allocated to IOS, and protected from access by some registers (TODO).

Broadway / IOS Global Memory Locations

Address	Size	(Typical) Value	Description
0x80000000	4	0x52535045	Game Code 'RSPE' (Wii Sports)
0x80000004	2	0x3031 (01)	Maker code
0x80000006	1	0	Disc Number (multidisc games)
0x80000007	1	?	Disc Version
0x80000008	1	?	Disc Streaming flag
0x80000009	1	?	Disc Streaming buffer size
0x80000018	4	0x5D1C9EA3	Disc layout magic (Wii)
0x8000001C	4	0xC2339F3D	Disc layout magic (GC)
0x80000020	4	0x0D15EA5E	Nintendo Standard Boot Code.
0x80000024	4	0x00000001	Version (set by apploader)
0x80000028	4	0x01800000	Memory Size (Physical) 24MB
0x8000002C	4	0x00000023	Production Board Model
0x80000030	4	0x00000000	Arena Low
0x80000034	4	0x817FEC60	Arena High
0x80000038	4	0x817FEC60	Start of FST (varies in all games)
0x8000003C	4	0x00001394	Maximum FST Size (varies in all games)
0x80000060	0x24	Debugger Hook	Hook is PPC assembler used by Debugger. If nothing is written to 0x60, SDK titles will write the 0x20 bytes of instructions automatically.
0x800000EC	4	0x81800000	Dev Debugger Monitor Address (If present)
0x800000F0	4	0x01800000	Simulated Memory Size
0x800000F4	4	0x00000000	BI2
0x800000F8	4	0x0E7BE2C0	Console Bus Speed
0x800000FC	4	0x2B73A840	Console CPU Speed
0x80001800	0x1800		Unused Exception Vector area often used for loader stubs and reloaders as this area is never cleared or used.
0x800030D8	4	0xffffffff	Seems to be always set to 0xffffffff by official NAND titles, including the system menu. This means the value carries over to disc titles.
0x800030E6	4	?	something about console type?
0x800030F0	4	0x00000000	DOL Execute Parameters
0x80003100	4	?	Physical MEM1 size
0x80003104	4	?	Simulated MEM1 size
0x80003118	4	?	Physical MEM2 size
0x8000311C	4	?	Simulated MEM2 size
0x80003130	8	0x933E0000, 0x93400000	IOS Heap Range
0x80003138	4	0x00000011	Hollywood Version
0x80003140	4	0x00090204	IOS version (090204 = IOS9, v2.4)
0x80003144	4	0x00062507	IOS Build Date (62507 = 06/25/07 = June 25, 2007)
0x80003158	4	0x0000FF16	GDDR Vendor Code
0x8000315C	4	0xdeadbeef	During the boot process, 0x315c is first set to 0xdeadbeef by IOS in the boot_ppc syscall. The value is later partly overwritten by SDK titles.
0x8000315D	1	0?	"Enable legacy DI" mode (0x80 = yes)
0x8000315E	2	0x0113	"Devkit boot program version", written to by the system menu. The value carries over to disc games. 0x0113 appears to mean v1.13, which is the latest version of the boot program (found in System Menu 4.3).
0x80003160	4	0x00000000	Init semaphore (1-2 main() waits for this to clear)
0x80003164	4	0x00000000	GC (MIOS) mode flag?
0x80003180	4	0x52535045	Game ID 'RSPE' Wii Sports ID. If these 4 bytes don't match the ID at 80000000, WC24 mode in games is disabled.
0x80003184	2	0x80	Application type
0x80003188	4	0x00351011	2 byte IOS, 2 byte apploader version -> IOS 53, Apploader version 16.17
0x8000318C	4	0x00000000	Title Booted from NAND (Launch Code)
0x80003190	4	0x00000000	Title Booted from NAND (Return Code)
0x80003194	4	0x00000000	While reading a disc, the system menu reads the first partition table (0x20 bytes from 0x00040020) and stores a pointer to the data partition entry. When launching the disc game, it copies the partition type to 0x3194. The partition type for data partitions is 0, so typically this location always has 0.
0x80003198	4	data partition offset	While reading a disc, the system menu reads the first partition table (0x20 bytes from 0x00040020) and stores a pointer to the data partition entry. When launching the disc game, it copies the partition offset to 0x3198.
0x80003400	0x100		NAND boot vector (Broadway initialization code from nandloader, entry point for NAND applications)
0x80003F00	0x132c100 (~19.2MB)		Standard application executable area
0x81330000	0x4d0000 (~4.8MB)		Loader executable area

By convention, applications should use the 0x80003F00 – 0x81330000 area for executable code and data loaded as part of their ELF/DOL, while loaders should use from 0x81330000 onwards. Applications can use the loader area and MEM2 as data work space once they are running, but they should restrict the sections contained in the DOL or ELF to the executable area only, since MEM2 is reserved as work area for the loader at that time. To preserve "return to loader" functionality, applications should never use the 0x80001800-0x80003000 area.