The ARM-CPU of the Octavo module emulates a 68k processor using a special JIT emulator called Pseudo JIT which supposedly can achieve the speed of a 68030 clocked with 3.2 GHz is going to move the Classic Amiga platform forward together with Vampire 68080 and the Warp 68060 accelerators for Amiga. But, did you know that there are several 68k JIT’s out there? MorphOS got Trance 68k JIT, while AmigaOS 4.x got its Petunia 68k JIT.

I am using MorphOS 3.15 daily, so that’s my 68k JIT experience. Trance 68k JIT is capable of running most of the AmigaOS 68k applications on any PowerPC computer that MorphOS runs on.

Yes, the combination of running PowerPC and 68k AmigaOS applications ain’t a problem at all on MorphOS. You run applications such as IBrowse, TVPaint, Filer, or any AmigaOS applications as if they were running on the PowerPC computer you are using. I am using TVPaint on my PowerBook G4 1.64 GHz and MorphOS 3.15. I love it! The Amiga feel is there all the way.

MorphOS runs almost any AmigaOS 68k application in its environment

Filer 4.07 requiring AmigaOS 2.x from 2002 works without issues on MorphOS 3.15

With MorphOS installed on your PowerPC hardware. It is ready to run AmigaOS 68k applications out of the box. The only downside is that it doesn’t support the Amiga custom chipset which leaves MorphOS AmigaOS experience a similar one to having a Draco Amiga clone.

The Amiga 68k JIT emulator running side by side in the MorphOS environment is named Trance JIT. It is a MorphOS JIT compiler, or code translator, for running AmigaOS applications that are also supporting 68k apps using RTG, MUI, ReAction, or even AHI dependencies within the MorphOS environment.

The 68k JIT has been part of the MorphOS operating system since MorphOS 1.4 (07.08.2003). I am using MorphOS a lot and I don’t feel the emulation at all. TVPaint runs at 1.64GHz PowerPC speed. There is simply no loading or rendering waiting. I love that.

Trance 68k JIT is running many Amiga applications, which were almost exclusively compiled for the 68k processor, while MorphOS itself is a PowerPC operating system. Including supporting 68k AmigaOS apps, MorphOS also runs PowerUP and WarpOS through library support. With the JIT compilation, increasing the speed of the emulation is possible to the fullest of what the PowerPC CPU can achieve. It does not interfere with the full integration of 68k and PowerPC tasks that MorphOS provides.

Amiga 68k JIT support is added during the boot process of MorphOS

TVPaint 3.6 AmigaOS 68k application from 1996 runs without issues on PowerBook G4 1.64GHz PowerPC laptop with MorphOS 3.15

The Trance 68k JIT exists in the form of an executable, run during boot, and a shared library. Although it is not technically part of the kernel, and MorphOS can run without it. When MorphOS is ported to x86 it will lose the 68k compatibility. If a Pseudo JIT type of 68k JIT could be added to MorphOS x86 version. Now that would be neat.

Trance is however considered a fundamental part of MorphOS and one of its most powerful features. So losing a 68k JIT feature will be a step back in my view. The 68k JIT emulation is one of the reasons that I am using this fantastic OS.

The compatibility of 68k made applications is as mentioned very high. I made a poll about what sort of Guide that people want me to do next and so I decided to create a nice AmigaOS 68k JIT application guide for MorphOS. There are few to no 68k instruction sequences or applications which cause any problems.

Trance was developed by Ralph Schmidt and Teemu Suikki, with minor support from other MorphOS team members, Mark Olsen, Sigbjørn Skjæret, and Harry Sintonen.

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