Re: [hatari-devel] Movem and cycles

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Good news.

Do you need some tests ?

I'd like a better CPU accuracy for pinball dreams (it needs precise cycles counting for Videl screen break between the marquee and the pinball table). I've got a Videl emulation code that is working (from hatari 1.6 ;) but needs a better accuracy.




Le 04/02/2017 à 20:11, Nicolas Pomarède a écrit :
Le 04/02/2017 à 20:07, Laurent Sallafranque a écrit :
Hi Toni,

Yes, I know div/mul algo are not known on 68020/68030.
I was just thinking about a general improvement of the cycles counting
with memory access.

I think that memory access are not  taken into account in 68030 mode (or
wrongly taken into acount).

I mean actually, hatari reads a movem.l (a6)+,d0-a4 in 16 cycles instead
of about 120 cycles.
I would love to see my falcon reading all this memory in 16 cycles.
I think the memory access is not taken into account for MOVEM.

I know there's still a lot of work to do to reach a better accurate
68030, but here, I was speaking of trying to reach a closer level of
accuracy (we start from far with movem ;)

Note : I'm actually working on better access cycle for 68030 in CE mode, should push some code soon, so movem and all other will have some much better timings (but this won't be the case for normal / prefetch mode)

As Toni said, if accuracy is really needed then 68030 CE mode will need to be used.

Nicolas







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