Re: [hatari-devel] Extended VDI screen in Falcon mode

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On torstai 07 helmikuu 2013, Vincent Rivière wrote:
> On 05/02/2013 10:55, Eero Tamminen wrote:
> > What kind of changes?
> 
> Here is my patch.
> I took yours and I fixed it for EmuTOS (CVS snapshots).
> Now extended VDI screens work fine in Falcon mode, in any case.
> 
> What needs to be known:
> 
> 1) The NVRAM video mode fix is the most important part. It forces a video
> mode similar to the one requested, so at startup EmuTOS picks up the
> right font (based on screen height) and palette (based on number of
> colors).
> 
> 2) The NVRAM patch needs to be applied also when the user selects Reset
> in the Hatari UI. I put a kludge in VDI_SetResolution(), certainly not
> the best place.

I moved that to NvRam_Reset() & reset.c and commited your patch:
http://hg.tuxfamily.org/mercurialroot/hatari/hatari/rev/285a171457c1


> 3) After that, Hatari does its Line A patch as usual. Ideally, only the
> screen dimensions would need to be fixed. The character cell height and
> number of planes should already be correct, thanks to the right boot
> video mode.

VDI mode needs to work also for all the old ST & STE TOS versions
which don't support NVRAM, so line-A patching is always needed.

> 
> 4) This works very badly with TOS 4.04. The startup sequence is certainly
> different than the EmuTOS one. However, the NVRAM patching should not
> hurt. I believe that most problems come from video memory allocation, or
> Line A patching. Anyway, it was already very broken before the patch.

it's also broken for TOS v3 in monochrome VDI mode when screen height < 480:
----
Illegal ROMmem wput at 00e0004e
Illegal ROMmem wput at 00e0004e
Illegal ROMmem wput at 00e0004e
.....
----

It's a bit strange that it breaks only for small sizes..



	- Eero