emulator: ProSystem
type: libretro
core_classification: community_fork
source: "https://github.com/libretro/prosystem-libretro"
upstream: "https://github.com/gstanton/ProSystem1_3"
profiled_date: "2026-03-24"
core_version: "1.3e"
display_name: "Atari - 7800 (ProSystem)"
cores:
  - prosystem
systems:
  - atari-7800

notes: |
  Atari 7800 emulator by Greg Stanton, ported to libretro by community
  contributors. The upstream is a Windows-only application with a single
  user-configured BIOS path. The libretro port adds automatic region-based
  BIOS selection: PAL carts get (E), everything else gets (U).

  Region is read from cartridge header byte 57 (core/Cartridge.c:214) or
  overridden by the internal database (core/Database.c:1739-1757).

  Both BIOS files are optional. The core runs without them but some titles
  have compatibility issues (startup encryption check). bios_Store() maps
  the BIOS into ROM at address (65536 - bios_size).

  No core option controls BIOS loading. If the file exists in the system
  directory, it is loaded automatically. No hash or size validation is
  performed on the BIOS file.

  The .info declares firmware_count=1 (U only), missing the PAL BIOS.

files:
  - name: "7800 BIOS (U).rom"
    system: atari-7800
    required: false
    hle_fallback: true
    size: 4096
    description: "NTSC/US BIOS, loaded when cartridge_region != REGION_PAL"
    source_ref: "core/libretro.c:585"

  - name: "7800 BIOS (E).rom"
    system: atari-7800
    required: false
    hle_fallback: true
    size: 16384
    description: "PAL/EU BIOS, loaded when cartridge_region == REGION_PAL"
    source_ref: "core/libretro.c:583"