SummerCart64/docs/memory_map.md

Internal memory map

name	base	size	access
SDRAM	0x0000_0000	64 MiB	RW
Flash	0x0400_0000	16 MiB	RW
Data buffer	0x0500_0000	8 kiB	RW
EEPROM	0x0500_2000	2 kiB	RW
64DD buffer	0x0500_2800	256 bytes	RW
FlashRAM buffer	0x0500_2900	128 bytes	R

N64 Memory map

name	base	size	access	mapped base	device	availability when
64DD registers	0x0500_0000	2 kiB	RW	N/A	N/A	DD mode is set to REGS or FULL
64DD IPL [1]	0x0600_0000	4 MiB	R	0x03BC_0000	SDRAM	DD mode is set to IPL or FULL
SRAM [2]	0x0800_0000	128 kiB	RW	0x03FE_0000	SDRAM	SRAM save type is selected
SRAM banked [2][3]	0x0800_0000	96 kiB	RW	0x03FE_0000	SDRAM	SRAM banked save type is selected
FlashRAM [2]	0x0800_0000	128 kiB	RW	0x03FE_0000	SDRAM	FlashRAM save type is selected
Bootloader	0x1000_0000	1920 kiB	R	0x04E0_0000	Flash	Bootloader switch is enabled
ROM	0x1000_0000	64 MiB	RW	0x0000_0000	SDRAM	Bootloader switch is disabled
ROM shadow [4]	0x13FE_0000	128 kiB	R	0x04FE_0000	Flash	ROM shadow is enabled
ROM extended	0x1400_0000	14 MiB	R	0x0400_0000	Flash	ROM extended is enabled
ROM shadow [5]	0x1FFC_0000	128 kiB	R	0x04FE_0000	Flash	SC64 register access is enabled
Data buffer	0x1FFE_0000	8 kiB	RW	0x0500_0000	Block RAM	SC64 register access is enabled
EEPROM [6]	0x1FFE_2000	2 kiB	RW	0x0500_2000	Block RAM	SC64 register access is enabled
64DD buffer [6]	0x1FFE_2800	256 bytes	RW	0x0500_2800	Block RAM	SC64 register access is enabled
FlashRAM buffer [6]	0x1FFE_2900	128 bytes	R	0x0500_2900	Block RAM	SC64 register access is enabled
SC64 registers	0x1FFF_0000	20 bytes	RW	N/A	N/A	SC64 register access is enabled

• Note [1]: 64DD IPL share SDRAM memory space with ROM (last 4 MiB minus 128 kiB for saves)
• Note [2]: SRAM and FlashRAM save types share SDRAM memory space with ROM (last 128 kiB)
• Note [3]: 32 kiB chunks are accesed at 0x0800_0000, 0x0804_0000 and 0x0808_0000
• Note [4]: This address overlaps last 128 kiB of ROM space allowing SRAM and FlashRAM save types to work with games occupying almost all of ROM space (for example Pokemon Stadium 2). Reads are redirected to last 128 kiB of flash.
• Note [5]: Used internally for performing flash writes from SD card
• Note [6]: Used internally and exposed only for debugging