Re: Creating DOS 3.2 Systems Masters where there were none

["schmidtd@my-deja.com" <schmidtd@my-deja.com>]

> BTW, perhaps it would be possible to put code in a 256-byte
> "DoubleBoot" ROM and put it on the disk controller card.
[...]
> Perhaps this is not possible - we do have the memory constraint
> of 256 bytes in the boot ROM,...

I count 5 bytes left over in the range $C6FB-$C6FF.  Not a lot of
wiggle room, to be sure.  I have gained a profound appreciation
of how Apple was able to preserve compatability over the years of
the ][ line - preserving absolute entry points, stable memory
maps, etc.  I have to believe that if they could have, they
would have done as you say - burned a ROM that was dual natured.

Some constraints they would have to have dealt with would be how
to specify what format you wanted to INIT in (13 or 16?), and
of course they would never have permitted the card to be slot
dependent.  They'd need some RTWS and File Manager changes, too.
It's probably a lot to stuff into the existing memory map.

I have a feeling that they also never imagined anyone would want
to "go back."  Witness the 80286 chip - you could flip from
v8086 mode into '286 mode, but you had to resort to trickery to
go back.  The same is true of MUFFIN - why the one-way street?
I think it's because they just didn't see the need.  Only the
benefit of hindsight gives us this perspective.

But anyway, back to the task at hand - it sure would be cool.
Got a ROM burner? :-)

- David Schmidt