Open IPL

Open IPL

Open a game and play. That is the promise behind SwanSong Open IPL.

Open IPL is the project's independently written minimal startup implementation for the WonderSwan family. It removes the BIOS hunt from current SwanSong releases and contains no bytes copied from an original Bandai system ROM.

0.2 and later contract

SwanSong 0.2 and later use Open IPL for:

• WonderSwan;
• WonderSwan Color;
• SwanCrystal; and
• Pocket Challenge V2.

The current app has no BIOS picker, original-firmware importer, firmware store, or compatibility override. The app never searches for, downloads, uploads, or shares an original startup image. Opening a supported authorized game is the only startup input required.

The production app and developer tools bind the startup identity open-bootstrap-v3. Reset, state restore, compatibility reports, private owned-ROM testing, and Translation Lab routes validate that same identity so a test cannot silently switch startup implementations.

Open IPL fixture and owned-game startup coverage is not a claim of perfect commercial compatibility or cycle-accurate equivalence to every original hardware revision. Compatibility reports must retain that distinction.

Release protections

• The app-payload gate rejects files named or shaped like firmware payloads.
• The prepared ares source removes upstream convenience firmware binaries.
• The corresponding-source archive gate rejects firmware-like binary extensions anywhere in its single validated source root.
• Source-free diagnostics exclude boot-ROM bytes and original firmware data.

Historical releases

Do not rewrite history when describing this change:

• SwanSong 0.1.0 used user-supplied startup files.
• SwanSong 0.1.1 made Open IPL the normal startup path but retained authorized original firmware as an optional private compatibility override.
• SwanSong 0.2 removes that import, storage, and override path completely.

Historical details remain in each version's release notes. Current 0.4 policy must not be presented as behavior that already existed in 0.1.x.