Re: [hatari-devel] New blitter code for xcount=1 nfsr=1

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 11/09/2020 à 09:06, Thomas Huth a écrit :
> Am Thu, 10 Sep 2020 17:44:23 +0200
> schrieb Nicolas Pomarède <npomarede@xxxxxxxxxxxx>:
>
> > Hi
> >
> > some times ago we had several examples of wrong blitter emulation
> > when xcount=1 and nfsr=1 at the same time.
> >
> > Various tests showed some different result depending on "source x
> > increment" values and other parameters maybe.
> >
> > Thanks to the work by Ijor who did a Verilog implementation of the
> > blitter, based on some reverse engineering as well as on the
> > blitter's schematics that Christian Zietz found some years ago, I was
> > able to fix this behaviour under Hatari and get all the cases to work
> > under Hatari using the small test program that Christian wrote at
> > this time (see attached BLIT.ZIP for reference)
>
> Great job! It's really cool to see Hatari getting more and more
> accurate!

Hi

yes, many components are now very accurate. Some work still need to be 
done for very low level emulation of the glue/mmu/shifter in some very 
specific cases, but apart from that ST/STE mode should be really 
accurate now (some work is still required for TT/Falcon)

> Any chance you could add that test from BLIT.ZIP to the "make test"
> regression test suite?

that's planned to be next on my todo list :) It's indeed a good test 
suite because it really checks many combinations and it should be rather 
simple to add to the test suite.

Nicolas