Re: Fast or direct load from disk.

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

On 2/24/2012 2:10 PM, Egan Ford wrote:
> On Feb 22, 2:35 pm, Egan Ford<dataj...@gmail.com>  wrote:
> > On Feb 22, 1:22 pm, Charlie<charlieD...@verEYEzon.net>  wrote:
> >
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> > > On 2/22/2012 11:49 AM, Egan Ford wrote:
> >
> > > > Hello all,
> >
> > > > I am looking for any code or suggestions on how to load a single
> > > > binary to a specific address and execute it directly from disk
> > > > (booting required) without DOS or ProDOS loading first.
> >
> > > > I've seen some games load very fast.  Is there a general method for
> > > > doing this floating around?
> >
> > > > Thanks.
> >
> > > I believe you can put a binary on track 0 sector 0 and it will load to
> > > $800 upon booting the disk. It will then jump to $801 and execute the
> > > code.  The byte at $800 tells the boot code how many sectors to load up
> > > to 16, I think.
> > > No DOS is involved.
> >
> > > Charlie
> >
> > Wow Charlie, that is stupid simple.  I just need to make sure I turn
> > off the drive motor.
> >
> > Thanks!
>
> Update.  I also have to move the arm.  And workout the skew.  I am
> going to pass on this method for now.

Moving the arm is not complicated--just a table and a time delay.

Physical to logical skew is also a simple lookup.

Take a look at the DOS boot loader to see how to do it.
..or just use the DOS boot loader as Open-Apple describes.

-michael

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