emulator: PCEE2 type: libretro core_classification: community_fork bios_mode: agnostic source: "https://github.com/WizzardSK/pcee2-libretro" upstream: "https://github.com/PCSX2/pcsx2" profiled_date: "2026-09-03" source_commit: "93aded21a46e60f3def27b2590eccb49d30d6a05" upstream_commit: "6db638dc0373769b4c5d5b5dd7ed6da641b9a18e" core_version: "v2.7.523" display_name: "Sony - PlayStation 2 (PCEE2)" cores: [pcee2] systems: [sony-playstation-2] bios_directory: "pcsx2/bios/" resources_directory: "pcsx2/resources/" data_directories: - ref: pcsx2-resources destination: "pcsx2/resources" source_ref: "pcee2-libretro/Libretro.cpp:414-442, pcsx2/Pcsx2Config.cpp:2388-2400" notes: | libretro port of current PCSX2, merged up to upstream 6db638dc (v2.7.523, pcee2-libretro/upstream.version). The build reports that version as library_version. Everything the port adds lives in pcee2-libretro/ and in the libretro renderer bridges, while the BIOS, CDVD, patch and database code is upstream PCSX2. InitializeConfig maps the PCSX2 folder layout under /pcsx2: AppRoot and DataRoot are that directory, Resources and UserResources are pcsx2/resources, Settings is pcsx2/inis, and EmuFolders::LoadConfig derives bios, memcards, cheats, patches, textures, gamesettings, cache, snaps, sstates, logs, covers, inputprofiles and videos from DataRoot (pcee2-libretro/Libretro.cpp:414-428, pcsx2/Pcsx2Config.cpp:2319-2336). A standalone PCSX2.ini dropped in pcsx2/inis contributes nine emulation sections as the baseline (Libretro.cpp:504-535), and the core options and the port overrides apply on top. BIOS detection is filename-agnostic. The core option pcsx2_bios lists every file of pcsx2/bios that IsBIOS accepts: a romdir whose RESET entry is followed by a readable ROMVER, whose fifth character gives the zone (Japan, USA, Europe, Asia, China, T10K, COH-H, Test, Free). With the option on auto, SettingsOverride selects the first accepted file (Libretro.cpp:578-618, pcsx2/ps2/BiosTools.cpp:80-197, 284-294). When no BIOS is configured or the configured name is missing, LoadBIOS falls back to FindBiosImage, which also filters on size between 4 and 8 MB (BiosTools.cpp:258-282, 317-369). The image is read into the 4 MB ROM region, and a file shorter than 2465792 bytes turns off the OSDSys parameter HLE. No hash is matched. Booting with no content starts the BIOS (Libretro.cpp:2090-2096). Companions derive from the selected image: rom1 and rom2 are tried as the full name plus extension, then with the extension replaced, and are skipped when absent. The nvm is read at the replaced extension and rebuilt with region and language defaults when missing or blank, and the mec is written back as 0x00020603 when it cannot be read (BiosTools.cpp:214-241, 366-367, pcsx2/CDVD/CDVD.cpp:136-205). The shaders, four interface fonts and GameIndex.yaml are built into the core (cmake/EmbedResources.cmake:19-31, pcsx2/CMakeLists.txt:1137-1157) and win over the copies on disk unless PCEE2_EXTERNAL_RESOURCES is set in the environment (pcsx2/EmbeddedResources.cpp:8-12, pcsx2/GS/Renderers/Common/GSDevice.cpp:372-387, pcsx2/ImGui/ImGuiManager.cpp:470-492, pcsx2/GameDatabase.cpp:1021-1050, Libretro.cpp:451-473). A missing resources directory is a warning, not a failure (Libretro.cpp:433-442). What the directory still supplies to this build is patches.zip. RedumpDatabase.yaml is read only by the Qt game summary (pcsx2/GameDatabase.cpp:1197-1210 has no caller in the core), game_controller_db.txt only by the SDL input source the port disables (Libretro.cpp:561-562, pcsx2/Input/SDLInputSource.cpp:701-706), the achievement sounds only with achievements enabled, which no core option or adopted ini section does (pcsx2/Achievements.cpp:943-951), and fullscreenui/no-save.png only by the save state selector, whose hotkeys the port clears (Libretro.cpp:564, pcsx2/ImGui/ImGuiOverlays.cpp:1461-1462). The port supplies Roboto alone to ImGui, so no emoji font is read. Per-game user files keep their PCSX2 locations under /pcsx2: cheats and patches as _.pnach (pcsx2/Patch.cpp:333-363), gamesettings/_.ini (pcsx2/VMManager.cpp:830-833), textures//replacements (pcsx2/GS/Renderers/HW/GSTextureReplacements.cpp:262-264), memcards/*.ps2, which the core creates and lists in the memory card options (Libretro.cpp:620-640). The DEV9 HDD image is named in the ini and created on demand. files: - name: ".bin" path: "pcsx2/bios/.bin" description: "PS2 BIOS image" min_size: 4194304 max_size: 8388608 required: true validation: [size] source_ref: "pcee2-libretro/Libretro.cpp:578-618, pcsx2/ps2/BiosTools.cpp:16-17, pcsx2/ps2/BiosTools.cpp:80-197, pcsx2/ps2/BiosTools.cpp:258-294, pcsx2/ps2/BiosTools.cpp:317-369" note: > Any file of pcsx2/bios whose romdir carries RESET and ROMVER. The 4 to 8 MB filter applies in FindBiosImage only. The core option scan and the auto selection accept any size that passes the romdir check. - name: ".rom1" path: "pcsx2/bios/.rom1" description: "DVD player ROM" max_size: 4194304 required: false source_ref: "pcsx2/ps2/BiosTools.cpp:214-241, pcsx2/ps2/BiosTools.cpp:366, pcsx2/MemoryTypes.h:13" note: > Tried as .bin.rom1 then .rom1, opened case-insensitively, skipped with a console line when absent. - name: ".rom2" path: "pcsx2/bios/.rom2" description: "Chinese ROM extension" max_size: 4194304 required: false source_ref: "pcsx2/ps2/BiosTools.cpp:214-241, pcsx2/ps2/BiosTools.cpp:367, pcsx2/MemoryTypes.h:14" note: > Same lookup as rom1. Present on Chinese region consoles only. - name: ".nvm" path: "pcsx2/bios/.nvm" description: "Console NVRAM (region parameters, language, iLink ID, OSD settings)" size: 1024 required: false hle_fallback: true source_ref: "pcsx2/CDVD/CDVD.cpp:47, pcsx2/CDVD/CDVD.cpp:136-188, pcsx2/CDVD/CDVD.cpp:207-238" note: > Read at .nvm, rebuilt in memory with region and language defaults when it is missing, short, or has a blank config block, and written back on save. - name: ".mec" path: "pcsx2/bios/.mec" description: "Mechacon version, one u32" size: 4 required: false hle_fallback: true source_ref: "pcsx2/CDVD/CDVD.cpp:49, pcsx2/CDVD/CDVD.cpp:190-204" note: > Read at .mec, written as 0x00020603 when it cannot be read. - name: "patches.zip" path: "pcsx2/resources/patches.zip" description: "Built-in game patch archive (pnach per serial and CRC)" required: false category: game_data source_ref: "pcsx2/Patch.cpp:117, pcsx2/Patch.cpp:289-317, pcsx2/Patch.cpp:365-405" note: > Opened read only from the resources directory when a game's patches are enumerated and searched for _.pnach, then .pnach. Files in the patches folder take precedence. A failure to open is reported once on screen. Not part of the PCSX2 source tree: PCSX2 builds fetch it from the pcsx2_patches releases, a rolling asset rebuilt on every patch commit. - name: "eeprom.dat" description: "DEV9 network adapter EEPROM" size: 64 required: false hle_fallback: true source_ref: "pcsx2/DEV9/DEV9.cpp:60-73, pcsx2/DEV9/DEV9.cpp:97-158" note: > Opened read-write and mapped from the process working directory by DEV9init. The built-in eeprom table is used when it cannot be opened.