Re: [hatari-devel] New WinUAE core issue with Bad Mood?

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Le 08/12/2014 17:37, Roger Burrows a écrit :
As you can see, we assume it's a 68030/68ec030 and try to clear the TTRs/ACRs.
If that doesn't work, we try the 68040/68060 initialisation.  Otherwise it's a
68030/68ec030 and we try to clear the TC.  Whether or not that works, we're
done 68030/68ec030 PMMU initialisation.

Hope that clears things up,


I understand better, this matches what I saw while tracing the boot.

Regarding 6ec030, this is what Tony told me regarding TC and his experience with 68ec030 on Amiga :

"Enforcer does use full MMU and it can work with some EC030's, at least partially. I had one, Enforcer worked, most other programs that use MMU simply hung the system immediately.

As I said previously, there are 680EC030's that have partially broken MMU, most operations work but some don't. Probably 68030's that got relabeled as EC because some MMU-only factory check/test failed."

So, it seems checking TC is not 100% foolproof to ensure you have a working MMU. If the cpu was made as a 68030, but failed at some quality checks in the factory and was relabeled/sold as a 68ec030, TC register will exist, but CPU might give undefined results when really using MMU translation's tables.

Well, I'm not sure some 68ec030 were used in some Atari or TT/Falcon extension boards, so this is rather theoretical in the end (unless you want EmuTOS to run on Amiga :) )


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