| Re: [hatari-devel] 060 + DSP -> freeze |
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Le 29/12/2014 11:37, laurent.sallafranque@xxxxxxx a écrit :
OK, I understand.
I thought about something like doing 2 68060 instructions and count only one cycle (or an average of the 2 instructions cycles), as the cycles are not really important here.
I mean CT60 users don't optimize their code, but just rely on the frequency of their accelerator card (many of them overclock it to higher frequencies).
Grouping 2 or 'n' instructions to have a total of 1 cycle for them is
more or less the same things as handling non integer cycles for an
instruction : in both cases, this means you need to maintain a counter
or an history to propagate the integer part of this counter as soon as
you reach a specific integer threshold (for example, group several
instructions until the total is at least 4 cycles)
Like this, it could "simulate" a 66 Mkh core (2x 32 Mhz), which is close to the CT60 frequencies.
Of course, this would only be available for 68060 emulation (we could also add an entry into the GUI for CT60 emulation now (32 Mhz for now)).
I know this is not really clean, it's just a thought like this, but it would be a nice feature to have a "close" CT60 emu in the next Hatari release ;)
(only if easily feasible of course).
If such an option is added, it could be common to all the cpu, if the
user really wants to try non existing config such as a 12 MHz 68000 STF,
why not, it's just likely to give strange results as soon as rasters of
MFP timers are used.
But this could also be interesting to simulate NTSC STF wher ewe know
the 68000's freq is slightly different from a PAL STF.
We could have an "advanced" setting panel to change parameters that are
normally non-existing on real machines.
Doing this cleanly require a lot of refactoring, so I don't think it
will happen now. Main goal should first be to backport all specific code
that I added to old UAE core into the new WinUAE core to be able to run
all complex STF/STE demos.
Nicolas