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Core sources and tools for the MIST board
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68881/2 #124

Open UgoCaneFifone opened 4 years ago

UgoCaneFifone commented 4 years ago

Hi, can be supported the FPU 68881 or 68882 in the mist core ?

harbaum commented 4 years ago

Sure. But someone needs to write a 68881 FPU. Can you do that?

Most people don't see much benefit in this since only very few software ever used that.

jotego commented 4 years ago

That is a part it has always called my attention. But I am afraid to do it only to find out that no software uses it.

UgoCaneFifone commented 4 years ago

Sculpt 3D/4D uses 68881 And the best would be to emulate an A3000: The Amiga 3000 was designed as the third generation high performance Amiga system by Commodore around 1988-89. Unveiled in 1990 with much fanfare, (even a BYTE Magazine cover article) the A3000 incorporates a high performance Motorola 68030 CPU at 16 or 25 MHz, and MC68881/16 or 882/25 floating point coprocessor into a full 32 bit system architecture with 32 bit memory access. In comparison to Intel systems, the A3000's 68030 is about on par with a 80386.

UgoCaneFifone commented 4 years ago

Or ...better support in the Mist a 68040 with FPU for a total Amiga compatibility till the last Commodore model.

sorgelig commented 4 years ago

No, better is 68060@100MHz. Why you limit yourself? ;)

harbaum commented 4 years ago

You are talking about Amiga? This wasn't obvious from the initial request. I thought you were referring to the 'mist' core which implements an Atari ST. At least on the ST only very few software ever made use of the FPU.

If you want to go the a3000 route i propose you start with the 68030 mmu. This has a benefit by itself and you can then add the 68881 to complete the setup.