Files
libretro/emulators/a5200.yml
Abdessamad Derraz de1940d57c feat: hle_fallback on 39 emulator profiles (266 entries)
Batch analysis of all 273 profiles to identify HLE/embedded
fallbacks. Added hle_fallback: true where the core has verified
software replacement for missing BIOS files:

- Embedded ROMs: vice (102), ep128emu (22), fuse (18), frodo (4)
- HLE BIOS: bsnes* (33 across 3 profiles), puae (9 AROS),
  noods (4), melonds* (6 FreeBIOS), flycast (3 reios)
- Open-source replacements: sameboy (8), pokemini (1), gpsp (1)
- Built-in fallbacks: np2kai (7), atari800 (6 Altirra),
  picodrive (3), quasi88 (4), gambatte (2)

Conservative: only added where notes or source code confirm HLE.
Skipped 50+ profiles where files are optional alternatives, not
HLE replaceable (neocd, opera, kronos, pcem, etc.)
2026-03-19 13:03:48 +01:00

52 lines
2.1 KiB
YAML

emulator: a5200
type: libretro
source: "https://github.com/libretro/a5200"
profiled_date: "2026-03-18"
core_version: "2.0.2"
display_name: "Atari - 5200 (a5200)"
cores:
- a5200
systems:
- atari-5200
# a5200 is a dedicated Atari 5200 emulator forked from Atari800/Atari++ codebase.
# It loads the official 5200 OS ROM from <system_dir>/5200.rom (2048 bytes, mapped
# to memory at 0xF800-0xFFFF via MEMORY_InitialiseMachine).
#
# If 5200.rom is missing or the user selects "internal" via core option "a5200_bios",
# the core falls back to Altirra 5200 OS, an open-source replacement compiled from
# Altirra-3.20-test4 (altirra_5200_os.c). The fallback has reduced compatibility
# compared to the original Atari OS ROM.
#
# BIOS loading (libretro.c:409-500):
# 1. check_bios_variable() reads core option "a5200_bios" (official/internal)
# 2. load_bios() attempts to read <system_dir>/5200.rom (0x800 bytes)
# 3. On failure or "internal" selected: memcpy from ROM_altirra_5200_os fallback
#
# Cartridge detection (atari.c:169-236):
# Auto-detects cart type from header bytes and size. ROM database in cartridge.c
# maps MD5 hashes to cart types (standard 8K/16K/32K/40K, bounty bob, super cart).
files:
- name: "5200.rom"
path: "5200.rom"
size: 2048
required: false
hle_fallback: true
note: >
Atari 5200 OS ROM. Provides the built-in OS routines used by all 5200
cartridges. Without it, the core uses the Altirra open-source replacement
which has lower compatibility with some games. Core option "a5200_bios"
controls whether to use this file or the internal fallback.
source_ref: "libretro/libretro.c:58-59, libretro/libretro.c:409-500, emu/memory.c:46"
notes:
altirra_fallback: >
The built-in Altirra 5200 OS (from altirra_5200_os.c, 0x800 bytes) is a free
replacement that works for most games but some titles require the original ROM
for full compatibility. The core displays a notification when falling back.
cart_db: >
cartridge.c contains an MD5-based ROM database for automatic cart type detection
(standard, EE banked, bounty bob, super cart variants). Unknown ROMs are detected
by size heuristic.