jpolo1224
7bdcd1be7c
Pause did not stick. The stuck-paused backstop resumes a VM that is paused
with nothing covering the screen, reasoning that such a state can only be a
lost resume. That held while every pause came with a frontend over it --
pauseForOverlay() is what the quick menu, the library and backgrounding all
use. The second screen's Pause tile is the only caller of plain pause(), and
it deliberately leaves the game on screen, so the backstop undid it 700ms
later. That is the "pause immediately unpauses itself" two people reported.
A pause the user asked for is now marked as such and the backstop leaves it
alone; resume() clears the mark.
Tiles were different heights. An active tile appends a state line ("\n❚❚" on
Pause, likewise Fast Forward), and with maxLines alone a tile grew the moment
you used it, so the row went ragged -- which is what made Fast Forward the
one people noticed. Every tile now reserves both lines whether or not it is
showing state, which also scales with the text size instead of a fixed
height, and row children stretch to the tallest so a Button's padding cannot
show as a ragged edge against a TextView's.
On-screen buttons get rapid-fire (#619). Physical buttons have had turbo and
the on-screen ones never did, which is the asymmetry the request was about --
and it is the same asymmetry tap-to-hold had in the other direction. Per
button, off by default, cycled from the editor toolbar. It runs on the macro
Frequency timer rather than a second one of its own, so it inherits the
sampling floor that stops the fastest settings from emitting presses the VM
never samples, and it composes with tap-to-hold: set both and a tap starts
the autofire and the next tap stops it.
Feature requested by shinobumaehara (#619)
ARMSX2 — Native ARM64 JIT Fork of PCSX2
ARMSX2 is a free and open-source PlayStation 2 (PS2) emulator based on PCSX2. Its purpose is to emulate the PS2's hardware, using a combination of MIPS CPU Interpreters, Recompilers and a Virtual Machine which manages hardware states and PS2 system memory. This allows you to play PS2 games on your phone, PC, or gaming handheld, with many additional features and benefits.
Thank You
The ARMSX2 team is eternally indebted to the PCSX2 project it is based on. We are so fortunate to build on their 20 years of hardcore development.
About This Fork
The upstream PCSX2 project ships an ARM64 interpreter build for ARM, but its high-performance JIT recompilers (EE, IOP, VU0, VU1, and vtlb fast memory) are x86-64 only.
This fork exists to close that gap. The goal is to preserve the correctness features of 20 years of PCSX2 development, while generating the fastest native ARM performance possible.
Current status:
- ✅ EE (Emotion Engine) recompiler — integer, float, MMI, COP0/COP1/COP2, branches, load/store
- ✅ IOP (I/O Processor / R3000A) recompiler — full integer, load/store, branches, coprocessors
- ✅ VU (Vector Unit) recompiler — microVU skeleton + Upper FMAC vector ISA complete; Lower ISA and runtime complete
- ✅ vtlb fast memory
- ✅ Native ARM64 binary builds and boots the PS2 BIOS
- ✅ 2D games are already playable
- ✅ 3D games run
Why LLMs / AI Were Used
A word on methodology:
The x86-64 JIT code in upstream ARMSX2 is already proven correct — it has run thousands of PS2 titles for years. The challenge in this port is not emulator design or JIT theory; it is mechanical translation of a large, well-understood x86-64 assembly codebase into equivalent ARM64 assembly (via VIXL) while preserving the exact same register-allocation contracts, block lifecycle, and recompiler semantics.
Large language models (LLMs) were used as an accelerant for this translation work — pattern-matching x86 JIT boilerplate to ARM64 equivalents, scaffolding emit routines, and keeping the porting velocity high. The JIT logic (block compiler, dispatcher, analysis passes, flag pipelines, clamping rules, Tri-Ace hacks, etc.) is taken directly from the upstream x86 implementation and validated against it. Nothing was hallucinated from scratch.
In other words: the hard engineering was done by the PCSX2 team over two decades. The hard typing — translating ~50k lines of x86 emitter code into ARM64 — is what AI helped compress.
System Requirements
ARMSX2 targets ARM64 across desktop (macOS, Windows, Linux) and mobile (Android, iOS/iPadOS), all from the single shared core. Our setup documentation page contains additional details on software and hardware requirements.
Please note that a BIOS dump from a legitimately-owned PS2 console is required to use the emulator. For more information, visit this page.
Building
Check out our github actions for the latest build recipe