It translates G3, G4, and AltiVec instructions, but not G5 instructions. īecause of the greater architectural differences between Intel and PowerPC processors, Rosetta operates at a higher level than the 68000 emulator does, as a user-level program that can only intercept and emulate user-level code. Rosetta is neither included nor supported in Mac OS X v10.7 'Lion' or later, which therefore cannot run PowerPC applications. Rosetta is optionally installable in Mac OS X v10.6 'Snow Leopard'. It has no user interface, and launches as needed with no notification of the user, which led Apple to describe it as 'the most amazing software you'll never see'. Rosetta is based on QuickTransit technology. It was embedded in Mac OS X v10.4.4 'Tiger', the version that was released with the first Intel-based Macs, and allows many PowerPC applications to run on Intel-based Mac computers without modification. This allows 68k and PowerPC code to be interspersed within the same fat binary.Īpple launched Rosetta in 2006 upon the Mac transition to Intel processors from PowerPC. This means that the nanokernel is able to intercept PowerPC interrupts, translate them to 68k interrupts (then doing a mixed mode switch, if necessary), and then execute 68k code to handle the interrupts. This emulator uses PowerPC features and is embedded at the lowest levels of the operating system, integrated with the Mac OS nanokernel.

With the launch of Power Macintosh, the Mac 68K emulator is part of System 7.1.2 and later. Each instruction set architecture is incompatible with its predecessor, necessitating a transition plan based on a software layer to emulate the previous instruction set on the succeeding one. Macintosh has used CPUs with several different instruction set architectures: the Motorola 68000 series, PowerPC, Intel x86, and ARM64 in Apple silicon. The second version, introduced in 2020 as a component of macOS Big Sur, is part of the Mac transition from Intel processors to Apple silicon, allowing Intel applications to run on Apple silicon Macs. The first version of Rosetta, introduced in 2006 in Mac OS X Tiger, was part of the Mac transition from PowerPC processors to Intel processors, allowing PowerPC applications to run on Intel-based Macs. The name is a reference to the Rosetta Stone, the artifact which enabled translation of Egyptian hieroglyphs. It enables a transition to newer hardware, by automatically translating software.

for macOS, an application compatibility layer between different instruction set architectures. Rosetta is a dynamic binary translator developed by Apple Inc.

Mac os x emulator