NES File Documentation

Overview

Feature Value
File Extension .nes
MIME Type application/x-nes-rom
File Type Nintendo (NES) ROM File
Developer Nintendo
Byte Order Little Endian
Primary Purpose To store game data for Nintendo Entertainment System games
File Header Contains "NES" followed by MS-DOS end-of-file character
Program ROM Size Varies, common sizes include 16K, 32K, 64K, 128K, 256K, and 512K
Character ROM Size Varies, common sizes include 8K, 16K, 32K, and 64K
Mapper Type Identifies the memory management controller type used
Region Indicates if the game is designed for NTSC, PAL, or both
Vertical Mirroring Indicates if vertical mirroring is used
Battery-Backed RAM Indicates if the game includes battery-backed RAM to save game data
Four Screen Mode Indicates if four-screen mode is supported
Trainer Indicates if a 512-byte trainer (for cheat codes) is present
Console Type Indicates the specific NES hardware version or clone type
TV System Indicates compatibility with NTSC or PAL television systems
PlayChoice-10 Indicates if the ROM is compatible with the PlayChoice-10 arcade system
VS Unisystem Indicates if the ROM is compatible with the VS Unisystem arcade system
RAM Size Indicates the size of RAM used by the game, if applicable