Re: [hatari-devel] New version of WinUAE's cpu core

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 20/11/2014 23:00, Laurent Sallafranque a écrit :
> Hi Nicolas,
>
> First, I thank you very much, it's a huge work that you've archieved here.
> Great work.
>
> I've quickly tested 2 demos that had worked with previous versions but
> were not working with the last version of hatari :
> - Moai : it works now
> - EKO system : it works also now ;)
>
> It looks promising.
> (Falcon mode, no MMU, cycle exact)
>
> But, I've also tested my current work and the timings differ a lot !
>
> I'll give this version a closer look, I think it'll take some time to
> check everything.

New WinUAE's code also changes timings depending on the memory being 
accessed (rom, chip ram, fast ram, ...). I haven't adapted this yet for 
Atari HW, but it could be a reason for different timings. I need to have 
a look at this next. CE mode depends on many parameters, both in CPU and 
in memory's handling.

> A thought : if one selects Falcon emulation, maybe we should select the
> MMU ON now (a Falcon had a MMU inside).

Well, it depends, MMU mode provides addresses translation and other 
memory protections, but it's less cycle accurate. So it would be better 
used for running unix like OS (think about Next) or TOS replacement 
where such functionnalities are needed.
Also, memory translation will take more cpu to emulate.

So, for game/demos and standard Falcon programs, I think it's better to 
disable MMU now, there're more cases where it's not needed than the 
opposite.

> Again, it's a great work !

Thanks, but the work you did on older winuae's version also helped to 
compare both cores and have a starting base.

Nicolas