PS2 ISO Launching · Neutrino

Open a PS2 .ISO in File Browser and Launchstation hands it to an external Neutrino installation.

Loader search order

1. Explicit path — Settings → Launching → Disc & image loaders → Neutrino.
2. ISO's device — case-tolerant /NEUTRINO/neutrino.elf and /neutrino/neutrino.elf forms.
3. mc0: — same case-tolerant forms.
4. mc1: — same case-tolerant forms.

Usable installation

The candidate needs a readable ELF and either modern config/system.toml or legacy system.toml beside the ELF. This follows the current RiptOPL-style completeness rule and avoids requiring one specific Neutrino module-folder generation.

Per-launch compatibility and video options

Select a valid PS2 ISO to open the R3Z Neutrino options screen. Five independent compatibility choices: fast disc reads (0), synchronous disc reads (2), unhook system calls (3), emulate dual-layer DVD (5), and fix game buffer overrun (7). Neutrino mode 1 is a dummy and is intentionally omitted.

Video choices: original 480i/576i, auto 240p/288p, auto 480p/576p and 1080i at width x1, x2 or x3. Video compatibility: Off or field-flipping modes 1–3. Debug Colors and PS2 Logo are independent toggles. Use D-pad to select/change, then Run or Cancel. Options reset each launch.

These are Neutrino command-line options, not changes to Launchstation's native disc drivers or global screen calibration. Settings → Launching → Disc & image loaders offers independent Disable Ember/POPStarter/Neutrino switches (Off by default).

Launch arguments

-bsd=<backend>
-dvd=<device:path/to/game.iso>
-qb
-cwd=<neutrino install directory>

Current Neutrino documents file-mode paths such as usb:, mx4sio:, mmce:, ilink:, udpfs: and ata:. The numeric unit suffix, where present, is accepted by Neutrino's backend detector.

Supported sources

Image validation

Launchstation opens the selected image and checks the ISO9660 primary volume descriptor at sector 16 for the CD001 signature before handing control to Neutrino.

Game ID, RetroGem and MMCE cards

Launchstation reads a valid PS2 title ID such as SLUS_123.45 from the selected ISO's root SYSTEM.CNF BOOT2 line. When the Game ID for discs setting is enabled, it displays the RetroGem-compatible launch signal. The reader works independently of MMCE and does not load or reset storage drivers.

When MMCE support is compiled and its storage stack is already running, Launchstation also makes a best-effort Game ID switch on responding MMCE cards. It skips the card containing either the ISO or Neutrino ELF, never switches an ambiguous memory-card alias, and never replaces an active MX4SIO stack to perform this optional step. A successful switch request may wait for the card to report ready; malformed or missing Game IDs do not stop the launch. This conservative policy differs intentionally from upstream R3Z's unconditional MMCE initialization.

Keep-IOP handoff

Quick-boot consumes the already-mounted backing store. ISO launches therefore use a dedicated keep-IOP loader path and do not obey the generic “Reset IOP before ELF launch” preference.

If a game does not boot

1. Verify the same ISO can be read in File Browser.
2. Set Neutrino explicitly to remove discovery ambiguity.
3. Confirm its system TOML layout.
4. Try a known-good ISO.
5. Report exact Launchstation hash, Neutrino version and device backend.