Re: Apple emulators that support "floating bus" video sensing?

["Michael J. Mahon" <mjmahon@aol.com>]

Dirk Thierbach wrote:
> sicklittlemonkey <Nick.Westgate@gmail.com> wrote:
>
> > On Mar 19, 7:03 pm, Dirk Thierbach <dthierb...@usenet.arcornews.de>
> > wrote:
> >
> > > Michael J. Mahon <mjma...@aol.com> wrote:
> > >
> > > > Oh, well--I hoped I had found a way to combine fast game computation
> > > > with correct-speed animation and delays.  Apparently not for emulators.
> > > > Most accelerators went to some lengths to achieve implementation of
> > > > processor acceleration combined with standard speed sound and (if
> > > > needed) disk access.
>
>
> > > So how did they do that?
>
>
> > By slowing down to 1MHz when certain I/O locations were accessed.
>
>
> That's what I thought. So, in other words, hardware accelerators can't
> do it correctly, either, unless they run at 1MHz.

No, by automatically controlling their speed (which emulators apparently
aren't smart enough to do) they work correctly.

In the specific case I'm trying to use, an accelerated machine correctly
samples floating video data and can pace itself to the video framerate.

Among other things, this allows a simple subroutine to "wait for
X frames" before returning, allowing constant time delays for users
to do something human, regardless of the accelerated processor speed.

-michael

NadaPong: Network game demo for Apple II computers!
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