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!