Re: [hatari-devel] "Infinite Live of the Blitter" STE demo doesn't work anymore

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Le 21/01/2015 22:11, Nicolas Pomarède a écrit :
thanks for pointing this ; this is indeed an important part of the mfp
emulation, this 4 cycles delay is involved in some rather tricky code.
I need to check, but I think here the irq happens during a rather long
blitter operation, which means it should not be delayed by 1 instruction
but considered effective as soon as the blitter finishes.

There was a bug when an MFP timer expired during a blitter transfer, the MFP's IRQ time was not correctly updated and this delayed the MFP interrupt by to the next cpu instruction, which in the case of this demo was enough to make it crash (because of a different order when executing MFP and VBL interrupt).

Should be OK now.


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