Nexen Version 1.4.40

Nexen v1.4.40 is a multi-system emulator release featuring major upgrades like a TAS editor with undo/redo, an infinite save state system, and ZIP-based movie formats. It enhances Sega Genesis support and includes improvements focused on Genesis hardware parity, startup compatibility, and repository consistency. The release emphasizes thorough testing and stabilization, aimed at integration verification rather than end-user use. Significant changes include expanded Genesis parity tests, improved diagnostic workflows, and script normalization for better automation. Testers are advised to avoid using this version for gameplay validation and to await the more stable v1.5.0 in June.

(HEY YOU!! We hope you enjoy! We try not to run ads. So basically, this is a very expensive hobby running this site. Please consider joining us for updates, forums, and more. Network w/ us to make some cash or friends while retro gaming, and you can win some free retro games for posting. Okay, carry on 👍)

Nexen v1.4.40 has been released. Nexen is a comprehensive multi-system emulator (NES, SNES, GB, GBA, PCE, SMS/GG, WS) built upon Nexen2, featuring notable upgrades: a fully-equipped TAS editor with undo/redo capabilities and greenzone functionality, an infinite save state system complete with a visual picker, a ZIP-based movie format supporting multi-format import/export, 🌼 Pansy metadata export for seamless integration with the Flower Toolchain disassembly pipeline, and ongoing enhancements for Sega Genesis, Atari 2600, and Fairchild Channel F support.

DOSBox-Staging Changelog:
Nexen v1.4.40 serves as a high-frequency integration checkpoint that incorporates significant Genesis parity efforts, improves startup compatibility, cleans up naming conventions, and stabilizes the release pipeline. This version is specifically released for artifact and CI verification rather than end-user testing.
🌟 Release Title
Nexen v1.4.40 – Thunder Before Bloom 1.5.0
🧭 Scope Of This Build
Area Outcome
🎮 Genesis hardware parity A substantial multi-issue parity update focusing on TMSS, controller protocol, DMA/FIFO timing, byte-lane behavior, and startup sequence
🧪 Regression depth Enhanced Genesis startup and VDP parity testing, including edge cases for mixed control/data sequencing
🧹 Repository consistency Ongoing naming normalization from Mesen to Nexen and batches for cleanup in workflow/scripts
📦 Release infrastructure Release metadata, README version links, and artifact production workflows prepared for v1.4.40
🛡️ Stabilization pass Cleaned low-risk warnings in active test surfaces and initialized coarse-seek guards in audio code
🔥 Major Change Themes Since v1.4.39
🎮 Genesis parity and startup convergence
Ongoing aggressive batches for Genesis parity across several issues, including startup/logo timing, TMSS behavior, bridge/MMU windows, and bus arbitration semantics.
Introduced and amplified deterministic startup compatibility gates and stress coverage to detect ordering-sensitive regressions early.
Strengthened VDP behavior concerning control/data pending sequencing and DMA/FIFO status windows.
Finalized gating for 3-button and 6-button controller protocols, along with associated parity tests.
🧪 Test expansion and reliability
Boosted targeted Genesis test coverage for startup transitions, delayed unlock states, mixed command ordering, and read/write lane interactions.
Implemented parity tests for stale high-byte latch behavior when full-word writes are made on VDP data/control paths.
Retained targeted regression runs for active Genesis suites following each stabilization pass.
🧰 Tooling, scripts, and diagnostics
Extended startup diagnostics and tracing workflows utilized for cross-emulator parity triage.
Continued consistency in the naming of scripts and artifacts to minimize confusion during automation and manual triage.
Enhanced workflow hygiene focused on repeatable builds and artifact publication.
🧹 Warning and stability adjustments in this release preparation
Removed mismatches between signed/unsigned assertions in Genesis VDP parity tests.
Addressed a potential uninitialized local warning path in seek_to_sample_coarse by initializing the probe struct.
Cleared previous corrupted-PDB linker warning issues through clean rebuild and output stabilization.
✅ Validation Summary For v1.4.40 Prep
Local release build gate passed for Release x64.
Core targeted Genesis regression filter passed:
GenesisControlManagerTests.
GenesisVdpDmaStartupLatencyTests.
GenesisVdpReadPortParityTests.*
Result: 50/50 tests passed.
📦 Expected Release Assets (v1.4.40)
Nexen-Windows-x64-v1.4.40.exe
Nexen-Windows-x64-AoT-v1.4.40.exe
Nexen-Linux-x64-v1.4.40.AppImage
Nexen-Linux-ARM64-v1.4.40.AppImage
Nexen-Linux-x64-v1.4.40.tar.gz
Nexen-Linux-x64-gcc-v1.4.40.tar.gz
Nexen-Linux-ARM64-v1.4.40.tar.gz
Nexen-Linux-ARM64-gcc-v1.4.40.tar.gz
Nexen-Linux-x64-AoT-v1.4.40.tar.gz
Nexen-macOS-ARM64-v1.4.40.zip
📣 Notes For Testers
This release is intentionally marked as a problematic testing version.
It should only be used to verify the release artifact plumbing and packaging.
For significant gameplay or parity validation, please wait for v1.5.0 in June.