Re: [hatari-devel] "Desktop Info..." freezes with VDI mode

[Thomas Huth <th.huth@xxxxxxxxx>]

Am Sat, 19 Oct 2019 17:09:07 +0200
schrieb Thomas Huth <th.huth@xxxxxxxxx>:

> Am Sun, 13 Oct 2019 22:43:34 +0300
> schrieb Eero Tamminen <oak@xxxxxxxxxxxxxx>:
> 
> > Hi,
> > 
> > On 10/12/19 11:58 AM, Nicolas Pomarède wrote:  
> > > Le 12/10/2019 à 06:50, Thomas Huth a écrit :    
> > >> Am Sat, 12 Oct 2019 02:28:10 +0300
> > >> schrieb Eero Tamminen <oak@xxxxxxxxxxxxxx>:    
> > >>> I experimented a bit with this and came up with the attached
> > >>> test patch.
> > >>>
> > >>> Would it make sense to enable that stuff unconditionally for
> > >>> VDI?
> > >>>
> > >>> I don't think it would slow it down noticeably and VDI mode
> > >>> isn't significantly faster than normal ST/STE video mode
> > >>> anyway.    
> > >>
> > >> IIRC we had Timer-B enabled in VDI mode in the past, until
> > >> someone disabled it for performance reasons?    
> > 
> > Good point, it's actually a *regression* from the last v2.2.1
> > release, as "Desktop info..." works fine in VDI mode with TOS v1.04
> > - 1.62 there.  
> 
> Ah, indeed, it's a regression caused by commit
> aee9b62dfea1c209a9b90002.
> 
> I think this is likely the correct fix:
> 
> diff --git a/src/mfp.c b/src/mfp.c
> index 645fd8a8..830d8832 100644
> --- a/src/mfp.c
> +++ b/src/mfp.c
> @@ -2287,9 +2287,8 @@ void MFP_TimerBData_ReadByte(void)
>                  * and store result in 'TB_MAINCOUNTER' */
>                 MFP_ReadTimerB ( pMFP , false );
>         }
> -
>         /* Video DE signal is connected to Timer B on the main MFP */
> -       if ( IoAccessCurrentAddress == 0xfffa21 )
> +       else
>         {
>                 if (bUseVDIRes)
>                 {
> 
> Nicolas, what do you think?

After having another look (also at the TT schematics to verify that the
DE signal is wired to the 2nd MFP, too), I'm feeling pretty sure that
this is the right fix, so I went ahead and committed it now.

 Thomas