Re: [hatari-devel] Hard drive emulation question

[Laurent Sallafranque <laurent.sallafranque@xxxxxxx>]

> Which one are you using for your tests ?

I always use the Gemdos HD emulation.

It wouldn't have to emulate precisely each type of harddrive of the 
planet (that would not be possible ;), but just introduce a delay to 
simulate a delay.

Regards
Laurent


Le 29/11/2024 à 10:19, Nicolas Pomarède a écrit :
> Le 29/11/2024 à 10:02, Laurent Sallafranque a écrit :
> > Hi Hatarians,
> >
> > I've got a little question about hard drive emulation under Hatari.
> >
> > When I code a game or a demo which loads data from the hard drive, 
> > the loading speeds varies a lot between my Linux fast PC and my real 
> > falcon compact  flash memory card (and I guess it would also vary 
> > with a real mechanical hard drive).
> >
> > Under hatari, it loads nearly instantly.
> > Under real falcon, there's a few ms to seconds delay before loading 
> > is finished.
> >
> > Would it be possible to introduce a "disk timing" parameter in the 
> > Hatari GUI parameters that would allow to "set virtually" a hard 
> > drive timing access ?
> >
> > There's no urge in this request, it's just for emulating closer "real 
> > hardware experience".
> >
> > Regards
> > Laurent
>
> Hi
>
> I made some similar changes for the FDC some times ago.
> commit 9dc550b0f2fb3 from 3/10/2021 adds a 4 cycles delay per word 
> transferred in the DMA FIFO.
>
> The same could be applied to HD, but there're several HD emulations :
>  - gemdos mode (mapped to the unerlying filesystem)
>  - acsi and scsi emulation on a disk file image
>
> each one would require a specific patch
>
> As gemdos HD mode is not a "real" HW feature, maybe the delays should 
> be added only when using acsi/scsi mode.
>
> Which one are you using for your tests ?
>
> Nicolas