Re: Looking for H/D patch for DOS 3.3

[dmanzer@wimsey.com (Doug Manzer)]

In article <50ctqo$nof@darla.visi.com>, nathan@visi.com 
(Nathan Mates) wrote:

>    Dos 3.3 disks have a fairly hard limit of 400K per disk, unless you
> pretty much rewrite some chunks from scratch. Dos 3.3 Launcher lets
> you mount a Dos 3.3 140K disk image on a ProDOS volume and use it that
> way. The restrictions on using Dos 3.3 Launcher is that programs can
> only use the lower 48K of ram; the upper 16 is reserved for ProDOS
> (that which actually does the disk i/o)

Thanks for the clue -- that would be enough for me, to use 
the lower 48. However, with that arrangement would I actually be
running DOS 3.3 or ProDos? It seems to me that all of 16k is not
needed to access a ProDos volume, considering that it takes only
a subroutine call to firmware on the interface card with
a buffer address and block number as parameters. What I'd like 
to do is run the real DOS 3.3 (patched only "slightly").

BTW where can I get DOS 3.3 Launcher?

I may end up patching DOS 3.3 myself, with a special firmware
entry point on my (home made) disk controller card, and
implementing DOS 3.3 140K "volumes" as files on the IBM side.

To boot, I'd auto load page 0, the vectors at the upper end 
of page 3 and $9000 (approx) to $BFFF, then run it from $3D0(?).

Regards, D.M.