ARMSX2

Overview

ARMSX2 is a free, open-source PlayStation 2 emulator made for ARM devices. An emulator is a program that imitates a console so that you can play its games on another device. ARM is the kind of processor found in nearly all phones, tablets and handhelds, and in Apple Silicon Macs. ARMSX2 is based on PCSX2, the reference PS2 emulator for computers, but it has its own ARM-native engine, so it runs much faster on these devices than a translated version would.

It exists for Android, iPhone and iPad, Apple Silicon Macs, Linux on ARM and Windows on ARM. This sheet focuses on Android, where most people use it. It is for people who have a PlayStation 2, a few of its discs, and a recent phone or handheld.

The PS2 is hard to emulate, so results depend on the game and on your device. Lighter games can run well on a recent high-end device, while demanding ones may stay slow. Before you spend time on a game, look it up in the compatibility list.

Key words explained

• BIOS: the small program built into the PS2 that starts it up and shows its menu. The emulator needs a copy of it to work. It is copyrighted, so you must copy it from your own console.

• Disc image: a single file that is an exact copy of a game disc. Common formats are ISO (a plain copy), CHD (a compressed copy that takes less space) and BIN/CUE (a copy split into a data file and a small text file that describes it).

• Dumping: making that copy from your own disc or console.

• Renderer: the part of the emulator that draws the picture. Vulkan and OpenGL are two ways for a program to talk to your graphics chip. Vulkan is newer and usually faster, if your phone's driver is good.

• Internal resolution: the size at which the game is drawn before it is shown. Native means the size of the real PS2. Higher values look sharper but need a lot more power.

• Frame rate: how many pictures per second the game shows. The PS2 games usually aim for 30 or 60.

• Memory card: on a PS2, games save onto a memory card. ARMSX2 simulates it with files.

• Save state: a snapshot of the whole game at one precise moment, which you can reload instantly. It is not the same as a normal in-game save.

• Per-game settings: options that apply only to one game, so a fix for one title does not affect the others.

• Controller mapping: the list that says which button of your controller does which PS2 button.

System requirements

• Android, minimum: Android 8.0 or later, a 64-bit ARM device running a 64-bit system.

• Android, recommended: a recent high-performance chip, a graphics chip with a current Vulkan driver, 6 GB of memory or more, and good cooling for long sessions.

• iPhone and iPad: iOS or iPadOS 18.0 or later, and a sideloading setup that enables JIT (a technique that speeds up emulators and that iOS blocks by default). An iPhone XR, iPhone SE (2020) or newer is recommended.

• Mac: an Apple Silicon Mac (M1 or newer recommended) with 8 GB of memory or more.

• Linux: a 64-bit ARM system with a working Vulkan or OpenGL driver and 8 GB of memory or more recommended.

• Windows: a native ARM Windows 11 device, such as a Snapdragon X PC. A normal x64 Windows PC is not the target of this program.

• The full list is on the system requirements page. Meeting it does not guarantee that every game runs.

To check your Android phone, open Settings > About phone and look at the Android version, the chip name and the memory (RAM). On some phones these are under Hardware information.

What you need

• The ARMSX2 app, see Installation.

• A PS2 BIOS dumped from your own console. Without it, the emulator cannot start any game. The BIOS dumping guide explains how.

• Your games, copied from discs you own. The disc dumping guide explains how, on a computer.

• Enough free storage. A PS2 disc image can take several gigabytes, and CHD takes less than ISO.

• A controller (optional but recommended). PS2 games use two sticks and many buttons, which are cramped on a touchscreen.

Neither the BIOS nor the games are provided with the emulator, and this page does not say where to get them.

• Keep the BIOS uncompressed. A BIOS inside a ZIP, RAR or 7z archive is refused.

• Supported formats on Android: ISO, CHD, BIN, IMG, MDF and GZ.

• For BIN/CUE games, keep all the files of the game together and never rename only one of them.

• Store your games in a normal folder on the phone or on an SD card, not in a cloud folder whose files are only downloaded on demand: they can disappear while you play.

Installation

Android. Go to the official download page. It offers three choices:

• Google Play (store page): the easiest, and updates are automatic.

• Stable APK: an installation file of a tested release. An APK is the file format of Android apps. Android asks you once to allow installs from your browser or file manager: accept, then open the file.

• Nightly builds: the newest builds, which get fixes first but may be less reliable. Use them only if you need a recent fix.

iPhone and iPad. The app is not on the App Store. It is installed by sideloading, which means installing an app by yourself, and JIT must be enabled. The iOS installation guide lists the steps (Developer Mode, LiveContainer, StikDebug and a script). It is longer than the Android install: follow it in order.

Mac, Linux and Windows. Builds are available from the download page when published; a platform without a build shows Coming soon. The source code is on GitHub.

First setup

On first launch a setup guides you. The setup guide describes the same steps. Take them in order.

1. Data location. Choose Internal for the simplest setup, or a writable folder on an SD card. This folder holds your memory cards, save states, settings, shader data and covers. Android deletes the app data when you uninstall the app, so export your saves first.

2. BIOS Location. Choose the folder that holds the BIOS you dumped. ARMSX2 checks each file and adds the valid ones. Select one entry and tap Use Selected BIOS: it becomes the default for all games. ARMSX2 keeps its own copy, so you can remove the source folder later.

3. ROM Location. A ROM here means a game file. Tap Pick ROMs Folder and choose the folder that contains your games (the folder itself, not one game). Approve the permission request, which lets the app keep reading this folder. Use Add Another Folder for more places: they are merged into one library.

4. Graphics. Keep the safe defaults offered: see Graphics and performance.

5. Tap Apply & Finish and wait for the first scan of your library to end (Scanning ROMs).

6. Start one game and check the picture, the sound, the controls and the saving to a memory card, before changing anything else.

It worked if your games are listed with their names. If not, see Common problems. You can later reopen the BIOS manager from the navigation drawer (BIOS Location) and test the PS2 menu without a game with Boot BIOS.

Adding your games

• To change the folders later, use Setup / Change Folders in the library.

• Use Scan to find new files, and Rescan All Games if you renamed, moved or replaced files.

• Subfolders are fine. Remove entries for storage that is no longer connected.

• Tap a game to start it. Its context menu holds the per-game settings, a custom name and visibility.

• If a game does not start, check the file format and that the copy is a good one, before changing settings.

Controls

• Touch controls, a controller or a keyboard and mouse can be used.

• To use a Bluetooth controller, first pair it in Android's Bluetooth settings, then start the game.

• The touch layout editor lets you move, resize, hide or change the behaviour of each on-screen control. You can save layouts as touch control profiles.

• Controller skins only change the look of the touch controls, not what they do. Import a pack from Settings > Custom Controller Skins, and optionally pick another skin for one game. See the controller skins guide.

Graphics and performance

Keep the global settings simple. Put fixes for one game in that game's own settings, from its context menu, so other games stay unaffected.

• Renderer: leave on Auto. If you must choose, use Vulkan on a device with a reliable Vulkan driver, and OpenGL as the fallback when Vulkan gives glitches or crashes.

• Internal resolution: start at native. Raise it only if the game already runs at full speed, one step at a time.

• Aspect ratio: Automatic.

• Deinterlacing: Default. (Some PS2 games draw half of the picture lines at a time; deinterlacing joins them.)

• Custom Adreno drivers: optional, for devices with a Qualcomm Adreno graphics chip whose stock driver causes problems. Leave them off unless a game needs them.

• Patches and advanced settings: leave off until the game runs well, then change one option at a time and test.

• Per-game BIOS: in a game's settings, you can assign another installed BIOS, or choose Use global. Restart the game after changing it.

Phones slow themselves down when they get hot. Take off a thick case, and take breaks on long sessions.

Saves

• In-game saves are written to a virtual memory card, as on the real console. They are the safest kind.

• Save states capture the exact moment, but may stop working after an update: also save in the game.

• Everything is stored in the data location chosen at setup. Copy that folder to back up your progress, and do it before uninstalling the app.

Updating

• Google Play updates the app by itself.

• With an APK, download the new one from the official page and install it over the old one.

• Back up your data folder before a big update.

Common problems

• The BIOS is not found. Cause: the dump is zipped, incomplete, or on storage that Android cannot read reliably. Fix: use an uncompressed BIOS, copy it to the phone's local storage, import it again and tap Refresh.

• The wrong BIOS starts. Cause: a game's own BIOS setting overrides the global one. Fix: check both, then restart the game.

• The library is empty. Cause: Android no longer grants access to the folder. Fix: open Setup / Change Folders, select the folder again, then run Scan or Rescan All Games and wait for it to end.

• A game is missing. Cause: unsupported format or a folder not in the list. Fix: check the extension, add the folder, rescan.

• Games appear twice. Cause: overlapping folders (a folder and one of its subfolders), or two copies of the same game. Fix: remove the extra folder, then rescan.

• Performance got worse. Cause: a setting changed. Fix: put the renderer and internal resolution back to their defaults, turn off custom drivers and patches, then change one option at a time.

• The setup asks to restart after moving the data folder. Fix: restart ARMSX2.

• The game folder is lost after a reinstall. Cause: Android does not always keep folder permissions. Fix: select the folder again.

Going further

• Official documentation

• Compatibility list

• Frequently asked questions

• Source code and releases

• PCSX2 on a Windows, macOS or Linux computer, for the best PS2 experience.