| Address range | Size | Device |
|---|---|---|
| $0000–$07FF | $0800 | 2 KB internal RAM |
| $0800–$0FFF | $0800 | Mirrors of $0000–$07FF |
| $1000–$17FF | $0800 | |
| $1800–$1FFF | $0800 | |
| $2000–$2007 | $0008 | NES PPU registers |
| $2008–$3FFF | $1FF8 | Mirrors of $2000–$2007 (repeats every 8 bytes) |
| $4000–$4017 | $0018 | NES APU and I/O registers |
| $4018–$401F | $0008 | APU and I/O functionality that is normally disabled. See CPU Test Mode. |
| $4020–$FFFF • $6000–$7FFF • $8000–$FFFF |
$BFE0 $2000 $8000 |
Unmapped. Available for cartridge use. Usually cartridge RAM, when present. Usually cartridge ROM and mapper registers. |