CPU memory map
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| Addr | Size | Device |
|---|---|---|
| $0000 | $0800 | 2KB internal RAM |
| $0800 | $0800 | Mirrors of $0000-$07FF |
| $1000 | $0800 | |
| $1800 | $0800 | |
| $2000 | $0008 | NES PPU registers |
| $2008 | $1FF8 | Mirrors of $2000 every 8 bytes |
| $4000 | $0018 | NES APU and I/O registers |
| $4018 | $BFE2 | Cartridge Space: PRG-ROM, PRG-RAM, and Mapper Registers (See Note) |
| $FFFA | $0006 | 6502 Vectors: NMI, Reset, and IRQ/BRK, After this is the end of space for the CPU |
Note: Most Common Boards address ROM and Save/Work RAM in this format, Especially in Common INES mappers:
$6000-$7FFF = Battery Backed Save or Work RAM
$8000-$FFF9 = Usual ROM, commonly with Mapper Registers (see MMC1 and UxROM for example)
Vectors are at the end of the rom, like so:
$FFFA-$FFFB = NMI vector
$FFFC-$FFFD = Reset vector
$FFFE-$FFFF = IRQ/BRK vector
