Cross-dressing your computer
by Alan Zisman
(c) 2001. First
published in Vancouver Computes,
May
2001
Emulation?setting a computer to pretend to be a
different sort of computer--
is sort of the cross-dressing of the computer industry. Like cross
dressing,
it has a long, though sometimes seedy past.
Back in 1975, Bill Gates and his Paul Allen wanted to
develop a Basic
computer language for the original PC, the Altair. But they'd gotten no
closer to an actual Altair than an article in an electronics magazine.
'Borrowing' time on a Harvard computer, they emulated
the Altair's CPU,
using that to develop their Basic. They first tried it out on an actual
Altair when Paul Allen flew to New Mexico to demo it to Altair. The
birth
of Microsoft!
As modern Macs and PCs have gotten more powerful,
they've gotten more
power to spare?power that can be put to use in the rapid translation
required
to emulate a different system.
This has first become popular with gamers nostalgic
for older sytems.
Now, for example, www.emulation.net
lists emulators for over 50 different systems, from classic Commodore
computers
to Atari consoles, to modern Palm handhelds.
However, gamers quickly run into the problem of
getting software to
run on the emulated system. Clearly, there's no way to load a Super
Nintendo
SNES game cartridge on the typical home PC. A search on the Internet
for
SNES ROMs turns up images of many popular games, but the legality is
questionable?only
if you own an original game cartridge can you legally use a ROM image.
And while it is relatively straightforward to emulate
early console
systems, more modern systems are more of a technical challenge. And
companies
that are still selling game systems are reluctant to see their products
emulated. Nintendo has successfully kept most N64 emulators off the
market,
while Sony has tried, and so far, failed to use the courts to
discourage
Bleem and Connectix from marketing their Playstation emulators.
So don't hold your breath waiting for a Playstation II
emulation to
show up, free for the downloading.
Mac users have been particularly well-served by
emulation. Commercial
products like Virtual PC (also from Connectix) let Mac users install
their
choice of DOS, Windows 95/98/2000, or Red Hat Linux on their systems.
The
emulated PC can run standard PC software, use the Mac for Internet and
network access and more, just as if it was a standard PC. You'll want
as
fast a processor and as much RAM as you can afford, and you'll still
have
a performance hit, but it's certainly usable.
VPC 4 ups the ante with better support for installing
more than one
PC operating system and dynamic drives, which automatically expand as
more
space is required. Very slick.
Doing the opposite, emulating a Mac on a PC is harder.
While on the
lowest levels, PCs are pretty stupid, basic systems, much of what makes
a Mac is proprietary Apple code, the ToolKit, stored in ROM. Any
would-be
emulator has to be able to provide the ToolKit's services.
Three Mac emulators deal with the challenges in
different ways, with
differing results. None of them emulate a PowerPC?in all cases, you're
limited to the previous generation Macs.
Executor (www.ardi.com?US$150)
entirely
avoids
using Apple code for the ROM or even the operating system;
instead,
they've created their own system to run Mac software. Only two
problems.
First, in working around all of Apple's code, they lose the elegance of
the Macintosh?their system is ugly and awkward. Worse, however, is that
is simply doesn't work with most Mac software. A few programs run; most
don't.
SoftMac 2000 (www.emulators.com?US$229)
takes
a
different approach. To use this software, you need to be able to
use Mac ROMs?either by making an image of the ROMs from a working Mac,
or by installing actual Mac ROMs in a PCI card. (Emulators.com will
sell
these to you). Then you can install a copy of a real Mac operating
system
(up to OS 8.1), and install Mac software.
It works better than Executor, though still with
limitations. There
is no networking or Internet support, for instance. And if you try out
their downloadable version, note that there are even more limitations,
which are not clearly spelled out in the documentation or online.
There's
no sound support?try to change a sound setting and you will have to
reinstall
the operating system.
The pick of the litter, however, is Basilisk II (http://netti.nic.fi/~lpesonen/BasiliskII/).
Like
SoftMac
2000, it requires getting a Mac ROM image (and has a utility
to do that), and installing a real Mac OS. Unlike its commercial
competition,
though, it's much less limited. It's able to offer network and Internet
support, for example. And it's free.
Running a Mac on a PC takes more effort than the
opposite, and lacking
support for PowerPC processors, you won't be able to run the most
modern
software. But on fairly recent hardware, you'll end up with a Mac
that's
actually faster than the Macs that are being emulated.
And that's pretty neat!