Double Unofficial-Open-PS2-Loader

Copyright 2013, Ifcaro & jimmikaelkael
Copyright 2024, KrahJohilto
Copyright 2025-2026 chasebochamp
Copyright 2025-Present, Wolf3s and Ripto
Licensed under Academic Free License version 3.0 Review the LICENSE file for further details.

Introduction

Double Unofficial Open PS2 Loader (wOPL) is a 100% Open source game and application loader based on OPL for the PS2 and PS3 units. This version uses features that at the moment are not merged upstream and unique.

Changes in wOPL

v1.0

• Removal of UDPBD since there are not much users using this.
• Add a easter egg when booting on wOPL.
• Code cleanups/fixes and compiler warning fixes.
• Gui improvements.
• Art tar archive support.
• mmce support.
• New theme renamed png files.
• Added daf0x gamestar module.
• Modular pademu, Play your games without selecting modules.
• Disc cover enable.

v1.1

• Added USB option in BDM
• Reworked the mmce option(Suggestion by Hardlevel)

Art Tar

Your all cover arts should be stored using .tar format, stored on ART/art.tar

wOPL Easter egg

This easter egg will need to be activated using R1+R2+L1+L2+Start+Select

Changes in uOPL

• uOPL uses a slightly older build environment in an attempt to increase stability, more akin to OPL r2049
• Multi USB works without issues (workaround)
• ATA HDD support ala grimdoomers fork
• UDPBD support (as a build variant) ala tihmstar & el_isra forks (untested) - likely needs more work and testers to confirm
• Favourites Menu Page (R3 Toggle's Favorite Marker)
• Optional per-game settings for Neutrino core loading for alternative compatibility on the fly
• Additional Mode 7 ala Neutrino (works with both Neutrino and OPL core)
• Legacy apps paths with mass: work
• Two new built in themes <uOPL> & <uOPL-CF>
• Additional theme options
• Debug builds have the option to send LOGs to a BDM device
• Disable all button added for cheats selection menu
• Cancel pending ART requests at launch (should stop a crash that occurs when traversing the games list quickly and suddenly launching a title)

Neutrino Support

Neutrino needs to be stored on either mc0:NEUTRINO/neutrino.elf or mc1:NEUTRINO/neutrino.elf with the usual setup of config and modules subfolders.
In game settings you will find an option Loader Core with the options of <OPL> or Neutrino

Supported devices: USB MX4SIO HDD (ATA) iLink UDPBD - untested HDD (APA) - untested (seems hit & miss for some games)

Neutrino does not support:
ZSO Format USBExtreme Format (Will result in <OPL> core being used instead even if Neutrino is selected)
PADEMU GSM Cheats (Will result in Neutrino still being used however these features will not be applied because Neutrino uses a diffrent sets of modules than OPL and u-OPL)

Get Neutrino

Additional Theme Options

These are all optional and will use default values if omitted.

Key	Description
wsX	Sets theme element posX position in widescreen (avoids the need for seperate 4:3 and 16:9 theme cfgs)
skip	If enabled will skip rendering of StaticImage types if there is no currently selected item
reflection	If enabled will render a reflection of GameImage or Coverflow types (not recommended for faked perspective/3D images)
plasma_blend_color	Optional secondary blend colour for plasma (now you can mix bg & blend colour, previously it was only bg & black)
Coverflow	New type will render 3 covers at a time, works with overlays and reflection etc
aligned=2	New value for "aligned" to right justify
use_settings_bg=1	If enabled all menus will displaysettings_bg.png from your theme instead of traditional plasma for the background

Release types

Double Unofficial Open PS2 Loader bundle included several types of the same wOPL version. These types come with more or fewer features included.

Type (can be a combination)	Description
Release	Regular wOPL release with GSM, IGS, PADEMU, VMC, PS2RD Cheat Engine & Parental Controls.
DTL_T10000	wOPL for TOOLs (DevKit PS2)
IGS	wOPL with InGame Screenshot feature.
PADEMU	wOPL with Pad Emulation for DS3 & DS4.
RTL	wOPL with the right to left language support.

How to use

W-OPL uses the following directory tree structure across HDD, SMB, and USB modes:

Folder	Description	Modes
CD	for games on CD media - i.e. blue-bottom discs	USB and SMB
DVD	for DVD5 and DVD9 images (if filesystem supports +4gb files)	USB and SMB
VMC	for Virtual Memory Card images - from 8MB up to 64MB	all
CFG	for saving per-game configuration files	all
ART	for game art images	all
THM	for themes support	all
LNG	for translation support	all
CHT	for cheats files	all

U-OPL will automatically create the above directory structure the first time you launch it and enable your favorite device.

For HDD (APA) users, OPL will read hdd0:__common/wOPL/conf_hdd.cfg for the config entry hdd_partition to use as your OPL partition. If not found a config file, a 128Mb +wOPL partition will be created. You can edit the config if you wish to use/create a different partition. All partitions created by OPL will be 128Mb (it is not recommended to enlarge partitions as it will break LBAs, instead remove and recreate manually with uLaunchELF at a larger size if needed).

USB/MX4SIO/iLink/HDD (ATA)

Game files should be ideally defragmented either file by file or by whole drive. Games larger than 4GB must be stored on a device formatted with exFAT, or if the device is using FAT32, the USBExtreme format must be used (see OPLUtil or USBUtil programs). We do not recommend using any defrag programs. The best way for defragmenting - copy all files to pc, format USB, copy all files back. Repeat it once you faced defragmenting problem again.

NOTE: partial file fragmentation is supported (up to 64 fragments!) since OPL v1.2.0 - rev1893

SMB

For loading games by SMB protocol, you need to share a folder (ex: PS2SMB) on the host machine or NAS device and make sure that it has full read and write permissions. USB Advance/Extreme format is optional - *.ISO images are supported using the folder structure above.

HDD (APA)

For PS2, 48-bit LBA internal HDDs up to 2TB are supported. HDD should be formatted with the APA partition scheme. wOPL will create the +wOPL partition on the HDD. To avoid this, you can create a text file at the location hdd0:__common:pfs:wOPL/conf_hdd.txt that contains the preferred partition name (for example __common).

Cheats

wOPL accepts .cht files in PS2RD format. Each cheat file corresponds to a specific game and must be stored in the CHT directory on your device. Cheats are structured as hexadecimal codes, with proper headers as descriptions to identify their function. You can activate cheats via OPL's graphical interface. Navigate to a games settings, enable cheats and select the desired mode.

cheat modes

• Auto Select Cheats: This mode will enable and apply all cheat codes in your .cht file to your game automatically.
• Select Game Cheats: When enabled a cheat selection menu will appear when you launch a game. You can navigate the menu and disable undesired cheats for this launch session. Mastercodes cannot be disabled as they are required for any other cheats to be applied.

NBD Server

wOPL now uses an NBD server to share the internal hard drive, instead of HDL server. NBD is formally documented and developed as a collaborative open standard.

The current implementation of the server is based on lwNBD, go there to contribute on the NBD code itself.

The main advantage of using NBD is that the client will expose the drive to your operating system in a similar way as a directly attached drive. This means that any utility that worked with the drive when it was directly attached should work the same way with NBD.

wOPL currently only supports exporting (sharing out) the PS2's drive.

You can use hdl-dump, pfs-shell, or even directly edit the disk in a hex editor.

For example, to use hdl_dump to install a game to the HDD:

• Connect with your choosen client (OS specific)
• Run hdl_dump inject_dvd ps2/nbd "Test Game" ./TEST.ISO
• Disconnect the client.

To use the NBD server in wOPL:

• Grab the latest beta version - go to the Releases section and grab the one at the top.
• Ensure OPL is configured with an IP address (either static or DHCP).
• Open the menu and select "Start NBD server". Once it's ready, it should update the screen to say "NBD Server running..."
• Now you can connect with any of the following NBD clients.

nbd-client

Supported: Linux, Windows with WSL and custom kernel

nbd-client requires nbd kernel support. If it isn't loaded, sudo modprobe nbd will do.

list available export:

nbd-client -l 192.168.1.45

connect:

nbd-client 192.168.1.45 /dev/nbd1

disconnect:

nbd-client -d /dev/nbd1

You'll generally need sudo to run this commands in root or add your user to the right group usually "disk".

nbdfuse

Supported: Linux, Windows with WSL2

list available export:

nbdinfo --list nbd://192.168.1.45

connect:

mkdir ps2
nbdfuse ps2/ nbd://192.168.1.45 &

disconnect:

umount ps2

wnbd

Supported: Windows

WNBD client. Install, reboot, open elevated (with Administrator rights) PowerShell

connect:

wnbd-client.exe map hdd0 192.168.1.22

disconnect:

wnbd-client.exe unmap hdd0

Mac OS

Not supported.

ZSO Format

As of version 1.2.0, compressed ISO files in ZSO format is supported by wOPL.

To handle ZSO files, a python script (ziso.py) is included in the pc folder of this repository. It requires Python 3 and the LZ4 library:

pip install lz4

To compress an ISO file to ZSO:

python ziso.py -c 2 "input.iso" "output.zso"

To decompress a ZSO back to the original ISO:

python ziso.py -c 0 "input.zso" "output.iso"

You can copy ZSO files to the same folder as your ISOs and they will be detected by wOPL. To install onto internal HDD, you can use the latest version of HDL-Dump.

PS3 BC

Currently, supported only PS3 Backward Compatible (BC) versions. So only COK-001 and COK-002/COK-002W boards are supported. USB, SMB, HDD modes are supported.

To run w-OPL, you need an entry point for running PS2 titles. You can use everything (Swapmagic PS2, for example), but custom firmware with the latest Cobra is preferred. Note: only CFW supports HDD mode.

Some notes for DEVS

Double Unofficial Open PS2 Loader needs the latest PS2SDK

Quick build commands:

# Direct Makefile build (canonical)
make

# Release package build
make release

Optional CMake wrapper (delegates to Makefile targets):

cmake -S . -B build
cmake --build build

Useful CMake targets: release, clean, rebuild, debug, iopcore_debug, ingame_debug.

Frequent Issues

w-OPL Freezes on logo or grey screen

Sometimes w-OPL freezes when loading config files made by older w-OPL builds.

hold START while w-OPL initializes to make it skip the config loading, then, you can save your own settings. fixing the issue.

Game freezes on white screen

Main game executable could not be found. Either game is fragmented or image is corrupted

w-OPL does not display anything on boot

You may have selected a Video Mode which your TV does not support. Hold Triangle and Cross while w-OPL initializes to reset your video mode to "Auto".