Request about OS Development

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Eh, PPC doesn't run 680x0 natively, does it?  Doesn't MorphOS and AmigaOS4 have an emulation layer for this?  Why can't AROS?

AROS is "AmigaOS" on x86_64, and it is a really fun project, I have learnt so much from it and a really recommend trying it out!

Thomas is correct though, from an architectural pint of view the design goals of AmigaOS are far removed from what is needed in an operating system in 2017.

As for adding an inbuilt 68k emulator to a x86_64, I tried it, and hit two problems: endianess (which was quite easy, but very time consuming to solve) and address space size. Unfortunately as soon as the OS and the app operate in different size address spaces they can no longer share data structures, which is a a key architectural design feature of AmigaOS (other operating systems are far more strict about control of the address space).

You can read my issues here: http://www.amiga.org/forums/showthread.php?t=72059

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When they (Apple) switched to intel they threw out MacOS and replaced it with MacOSX. This it the equivalent of installing Linux with an Amiga themed window manager and running AROS Hosted on it.

Which is exactly what should have happened to the Amiga 20 years ago.

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You can get big endian PowerPC chips, you can't get big endian x64 chips.

It's possible to create an x64 compiler which deals with the endian conversion (bonus points if you can figure out how to make it only do the endian conversion for data that really matters).

Hi psxphill, if you read my earlier post, I link to my inline 68k emulator. Endian issues are annoying but not a huge problem. They simply require a translation layer. In my 68k emulator the emulated 68000 is allowed access to the x86 address space, when running on AROS, all the OS data structures an Amiga App running in that space expects to find will be present and so the App will run (just as it does on 68k AROS). The big problem comes when trying to run the 68000 App on a 64bit processor like the x86_64, then the Amiga App can only see the first 4gig of memory, but all the the OS data structures and even the Application itself could be anywhere in a multi terabyte address space (this is address space, not simply installed RAM)... so it will fail and there is no way around this.

The 68k Amiga is firmly trapped in a 32bit world.