MorphOS is an AmigaOS-like computer operating system (OS). It is a mixed proprietary and open source OS produced for the Pegasos PowerPC (PPC) processor based computer, PowerUP accelerator equipped Amiga computers, and a series of Freescale development boards that use the Genesi firmware, including the Efika and mobileGT. Since MorphOS 2.4, Apple's Mac mini G4 is supported as well, and with the release of MorphOS 2.5 and MorphOS 2.6 the eMac and Power Mac G4 models are respectively supported. The release of MorphOS 3.2 added limited support for Power Mac G5. The core, based on the Quark microkernel, is proprietary, although several libraries and other parts are open source, such as the Ambient desktop. Developed for PowerPC CPUs from Freescale and IBM, it also supports the original AmigaOS Motorola 68000 series (68k, MC680x0) applications via proprietary task-based emulation, and most AmigaOS PPC applications via API wrappers. It is API compatible with AmigaOS 3.1 and has a GUI based on the Magic User Interface (MUI). Besides the Pegasos version of MorphOS, there is a version for Amiga computers equipped with PowerUP accelerator cards produced by Phase5. This version is free, as is registration. If unregistered, it slows down after each two-hour session. PowerUP MorphOS was most recently updated on 23 February 2006; however, it does not exceed the feature set or advancement of the Pegasos release. A version of MorphOS for the Efika, a very small mainboard based on the ultra-low-power MPC5200B processor from Freescale, has been shown at exhibitions and user gatherings in Germany. Current (since 2.0) release of MorphOS supports the Efika. ABox is an emulation sandbox featuring a PPC native AmigaOS API clone that is binary compatible with both 68k Amiga applications and both PowerUP and WarpOS formats of Amiga PPC executables. ABox is based in part on AROS Research Operating System. ABox includes Trance JIT code translator for 68k native Amiga applications. AHI – audio interface: 6.