| Re: [hatari-devel] WinUAE CPU core MMU option and CPU accuracy? |
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>> But maybe the timings in MMU mode are worse than in cycle exact or
>> prefetch mode.
>>
>> We should be careful with that before enabling the MMU
>
> Hi
>
> IIRC without looking at the sources now, cpu is indeed less
> cycle-accurate when MMU mode is set.
Yes. "Cycle-exact" (only 68000 is really cycle-exact) is not fully 68030
MMU compatible, data cache is not emulated.
Main problem is that 68030 caches logical addresses (I guess this
feature comes from original 68020+68851 combo, 68030 is sort of
integrated 68020+68851).
68040+ caches physical addresses which is much more emulation friendly.