Solutions in Modernizing GS (Re: Problems in "Modernizing" a //gs)

[pubpc1@library.ucla.edu]

I talked to an friend of mine that uses and programs an Amiga 500
(a computer that uses the 68000) and asked him about these supposed
problems in upgrading the GS.  Here's what he has to say:

Some Mac users have spammed csa2 and claim that the GS could never
be upgraded.

"Yeah, we Amiga users get spammed by those freaks too."

They doubt the derived 65C816 32-bit chips could have been made.

"That figures, we've been trying to convice them that they don't
have pre-emtive multitasking for ages and they don't get it.
Where there is demand, there will be supply.  Since Apple wanted
the GS dead, clone makers gave up their efforts and as a result,
Western Design Center gave up theirs.  That's why they placed
their emphasis on microcontroller applications."

Just for the benefit of their doubt, assuming that WDC did not
make a 32-bit variant one way or another, could the GS still be
upgraded?

"Absolutely. Apple wanted it dead, which is why they refused to
upgrade it.  In the early 1990's, a Mac Classic with big
memory and a hard drive was priced the same as a GS system
without a hard drive and the same processor as in 1986.  They
made it clear they wanted to push GS sales down so that they
could justify killing it.  This is not saying that even Mac
Classic prices were reasonable when you consider that Amiga 500
systems were selling for less that $800 fully equipped, but
the Classic was deliberately made a steal compared to the GS."

They say that the 68000 was more powerful clock for clock.
Having studied the 65C816, is this so?

"Clock for clock?  No way is the 68000 more efficient at all
tasks.  At the equivalent frequency, the 65C816 will beat a
68000 in many tasks.  If Apple put a 7MHz 65C816 into the GS,
it would beat a 7MHz 68000 Mac to a pulp in most tasks.  Even in
the 2.8MHz version that Apple crippled the GS with, it will
keep up with a 7MHz 68000 in a Mac on a good day.  Actually,
the 65C816 at 2.8MHz and the 68000 at 7MHz are pretty slow.
The Amiga deals with this by using custom hardware graphics
chips, which is why our graphics are so much better than the
equivalent Macs and don't slow down the computer."

How would you upgrade a GS without a 32-bit 65C816 derivative?

"I would put the fastest 65C816 that WDC has (20MHz) into a
motherboard that runs at this speed.  Then I would use 'the
Amiga Principle,' using custom chips to off-load work from
the CPU.  Put the equivalent of the Amiga graphics chipset
in (that TurboRez card that was cancelled is a good equivalent)
that provides multiple bitplanes and a hardware blitter.
Give SVGA output, like that Second Sight card offers.  Put
in a 68882 math coprocessor unit like the one that was
available for the GS on a card.  Then round it off by putting
in a modern version of the GS's Ensoniq sound chip.  8-bit
Apple II emulation could be moved into software easily.  Use
an IDE hard drives for the biggest bang for the buck and put
in at least 4MB, expandable to 16MB."

Is it too late to upgrade the GS?

"No.  If Apple dies and sells the technology, the GS, using
the Amiga Principle, can be revived.  The Amiga is being revived
by Gateway 2000, so it can be done.  The market for computers
priced at $600 is large and left by the void formerly filled
by the Amiga 500.  Apple could target this market with this
GS.  They could buy the rights to all the significant GS
software and bundle it together.  If people are willing to buy
GeoWorks based integrated software in a dedicated word processor
(for example, from Brother) for $400, this GS will sell like
crazy as an appliance computer."

Can this new GS evolve into something even better?

"Definitely yes.  If successful, Apple should move to upgrade
the GS's OS.  The first thing I would do is to slowly make the
GS toolbox reentrant.  I assume this is why you can preemtive
multitask under GNO/ME, but only have one Desktop program being
multitasked.  Then they could eventually migrate the platform
to PowerPC if things work out.  Keep the hardware graphics and
sound, port the GS toolbox to native PPC code, and emulate the
65C816."

The Mac folks say that this is like the PowerMac.

"Sure, except that it has sound and graphics features that we
Amiga and GS users like and it has the GS toolbox in native
code.  That's a big advantage.  Also, all you Apple II folks
would have such a GS now and Apple would be in much better
shape."

They say at some time backward compatibility must be cut

"Yes, but if you give users an upgrade path with backward
compatibility at each step, they will follow.  If you break
backward compatibility in a single step, they [the users]
will defect.  The GS is compatible with the IIe.  The
'Amiga-like' GS I am suggesting will break IIe compatibilty
but remain truly GS compatible.  Then the RISC based GS
will emulate the GS in software and eventually, after a
few years, go native.  At each step, give a few years in
between for users to migrate and be backward compatible
not with the very oldest model, but with at least the previous
one."

Based on my conversation with him, I'd say Apple would have
had a winner using the following timetable:

GS w/1MB:  1986
GS/30 (7MHz processor/30MB hard drive): 1987
'Amiga-like' GS:  1990
PowerGS (65K emulation):  1994
PowerGS (all native):  1997

-Scott G.