emulator: "emux (NES)"
type: libretro
core_classification: official_port
source: "https://github.com/libretro/emux"
upstream: "https://github.com/sronsse/emux"
profiled_date: "2026-03-23"
core_version: "0.1"
display_name: "Nintendo - NES / Famicom (Emux NES)"
cores:
  - emux_nes
systems:
  - nes

notes: |
  emux is a multi-system emulator by Sebastien Ronsse, supporting CHIP-8,
  Game Boy, NES, and Sega Master System as separate libretro cores.

  The NES core does not require any BIOS or firmware files.
  The .info declares no firmware_count.

  The NES has no boot ROM. CPU starts at the reset vector address
  stored at 0xFFFC-0xFFFD (cpu/rp2a03.c RESET_VECTOR).

  Cartridge loading in controllers/mapper/nes_mapper.c:
    - iNES header parsed (magic 0x1A53454E)
    - Mapper number extracted from flags6/flags7
    - Supported mappers: NROM (0), MMC1 (1), MMC3 (4)
    - PRG-ROM and CHR-ROM mapped via file_map(PATH_DATA, ...)

  Memory map from mach/nes.c:
    CPU bus:
      0x0000-0x07FF  WRAM (2 KB, mirrored to 0x1FFF)
      0x2000-0x2007  PPU registers (mirrored to 0x3FFF)
      0x4000-0x4013  APU registers
      0x4014         Sprite DMA
      0x4016-0x4017  Controller ports
      0x6000-0x7FFF  SRAM
      0x8000-0xFFFF  PRG-ROM

    PPU bus:
      0x0000-0x1FFF  CHR-ROM/RAM (pattern tables)
      0x2000-0x2FFF  VRAM (nametables, 4 KB)
      0x3F00-0x3F1F  Palette RAM

  system_directory obtained via RETRO_ENVIRONMENT_GET_SYSTEM_DIRECTORY
  (libretro/libretro.c:23-25) but not used for any file loading.

  is_experimental=true. No save states, rewind, or netplay support.
  Supported extensions: nes, bin, rom.

exclusion_note: "NES has no boot ROM, CPU starts at reset vector from cartridge"
files: []