Re: Apple IIGS Operating System

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

Linards Ticmanis wrote:
> Unfortunately, ADT is still 5.25" only. Modifying it for 3.5" should be
> fairly easy -- but somebody has to actually do it.
>
> Two things will need to be done: Porting it from DOS to ProDOS (this is
> probably the more difficult part) and then amending the protocol to deal
> with 800K images.

I've been thinking about this.  The port from DOS to ProDOS would
actually be very straightforward: the RWTS calls and ProDOS calls are
conceptually similar; it would pretty much be a 1-1 swap of routines.
So, I think getting ADT to run in a ProDOS environment would be fairly
easy.

I see the tricky bit as one of ADT's most important use cases: the bare
metal bootstrap.  You hook up your serial line, ship some data at the
Apple's serial port after doing IN#x, and it literally "types" a DOS
3.3 variant into the monitor and INITs a disk.  That, in my estimation,
would be tougher for ProDOS.  Mostly because I know less about the
internals.  But the ProDOS that gets blasted at the serial port would
need to have a driver imbedded in it for the 3.5" disk drive.  Is that
true for ProDOS 1.9?  I guess some experimentation would prove it one
way or another.  I do remember reading in Beyond ProDOS that the INIT
routine isn't even in the 5.25" floppy driver to save space... you need
to load the utilities to do that.  If they didn't bother for a Disk ][,
what hope is there we could init a 3.5" disk once the raw OS got
connected?

I suppose the rest of what gets shipped at the serial port could be
that utility that does the INITting.  Sounds like it's getting to be a
lot of data. :-)