Release 1.6.0

5DO 1.6.0

Released: 2026-11-08

5DO 1.6.0 is the compatibility-completion update. It closes the unique-title compatibility plan with 375 of 378 game-test-set titles playable under the documented binary beyond-title rule, publishes the authoritative 5DO/4DO/Phoenix comparison, tightens the remaining CD-ROM poll/speed/session behavior against Opera, and hardens settings and NVRAM persistence against locked or cloud-synced data folders.

Highlights

• Compatibility completion. The local collection covers 1,371 images, 414 unique titles, and a 378-title game/homebrew test set. 375 of 378 are Playable, the comparison has 0 Behind and 0 Regression rows, and the playable set is a strict superset of the 252-title 4DO/Phoenix peer union. The two Title-only rows and one No-video row are non-retail/add-on images.
• Authoritative 3-way matrix. The committed comparison and beyond-title ledger record the canonical disc, BIOS, disc hash, capture frame, screenshot, and failure reason for every title.
• CD-ROM parity. POLREMASK is a one-shot reset; only the three interrupt enables persist, and POLRE is write-one-to-clear. MODE SELECT page 3 stores Opera's MEI_CDROM_DOUBLE_SPEED byte (0x80) and updates the XBUS 2x status bit; a configured multi-speed drive caps at 1x when the guest selects single speed. SESSION INFO, TOC Q-position, and the volume-header readable-disc limit now match the reference. The CD-ROM save-state section is version 5.
• Persistence hardening. Settings and NVRAM writes fall back to a direct copy when a cloud-sync placeholder, read-only file, or delete-locked file rejects the atomic replace. The shell keeps running when a write still fails, guards startup media loading, preserves a newer build's settings as settings.json.v<version>.bak, and normalizes null/short Players arrays.
• Diagnostics and polish. FIQ source tracing, differential-panel audio gating and scripted input, nightly baseline comparison, complete tooltip coverage, and logged fallback paths.

Validation

• Full suite 2,061/2,061 passes in Debug.
• Build: 0 warnings, 0 errors. dotnet format --verify-no-changes and jb inspectcode --severity=WARNING are clean.
• 378-row ledger verification passes: 375 Playable, 2 Title-only, 1 No-video, 0 Not-loadable, 0 Behind/Regression, strict peer superset.
• The comparison generator --check reports the committed outputs are current.
• Road Rash boots for 600 frames in both compatible and accuracy profiles; the 50-title differential panel remains 50/50 frame hashes with 0 errors.
• Windows x64 is the validated target. Linux x64 full-suite and CLI/frontend smoke validation pass; GPU presentation under llvmpipe/SSH remains preview/best-effort. macOS and arm64 bundles are cross-published and architecture-validated.

Download

System	Bundle
Windows x64	5do-1.6.0-win-x64.zip
Windows arm64	5do-1.6.0-win-arm64.zip
Linux x64	5do-1.6.0-linux-x64.tar.gz
Linux arm64	5do-1.6.0-linux-arm64.tar.gz
macOS x64	5do-1.6.0-osx-x64.tar.gz
macOS arm64	5do-1.6.0-osx-arm64.tar.gz

Each bundle contains the framework-dependent single-file CLI and desktop app, the README/license/notices, whatsnew.md, and the release/legal docs. Install the .NET 10 Runtime first; the bundles do not include the runtime.

See the full release notes and release page for SHA256SUMS.txt.

Known limits

• Playability follows the documented binary beyond-title rule, not a full playthrough or a claim for every regional revision.
• CD command cadence is the remaining behavioral differential on the 50-title panel; the 3,000-frame showcase still diverges on Road Rash.
• VRR depends on the GPU, driver, monitor, and desktop; 5DO only avoids the blocking swap interval.