Emulation 101

Classic games never die. With emulators your PC is an arcade machine and console rolled into one. Take the journey with James 'Amiga4Eva' Matson

The highest form of flattery
Gaming technology is an industry that hurtles towards the future at such an incredible pace scientists haven’t yet created a device accurate enough to measure it. The kinds of numbers we’re talking about are in the ‘Duke Nukem Forever release date’ range, therefore – unquantifiable.

At full throttle most up-to-the-minute computers and consoles make the transformation into nostalgia before their power supplies have had a chance to leave a warm spot on the desk or carpet. Or – in the case of Dreamcast – before it makes it through the front door. We catch these machines in transition from latest tech to aged beast, and spend a large portion of our time playing games on them.

Some of these games – the really special ones – become entrenched in our ethos and serve as the standard against which all future games are judged.

S.T.A.L.K.E.R might be an all-singing all-dancing behemoth of dynamic lighting, but folk of the 8 and 16-bit generation still harbor a secret desire to fire up Super Metroid on the SNES for some old school nostalgic fun. Similarly, newly christened gamers may seek to understand why some games have become hall of fame candidates over the years.

The problem with this clandestine lust is usually one of entropy. Retro hardware and media doesn’t always stand the test of time in the same fashion as our desires.

Amiga disks become infested with CRC errors and SNES cartridges stop working no matter how many times you replace the 72 pin connector with something you sourced off eBay.

Enter the emulator, stage left.

Thanks to a combination of hard work, ingenuity and creativity, skilled enthusiasts have been able to create software engines to emulate the functionality of everything from the Sega Master System to the Nintendo 64 on our PC desktops, without having to worry about hardware failures or broken game cartridges.

Despite emulation having been around for many years prior – mostly in the form of ‘bridgeboard’ / software combinations to perform feats like running IBM software on the Commodore Amiga - the immense popularity of the Gameboy and its subsequent emulation on the PC pushed emulation into the mainstream.

Emulators created to reproduce the gaming joy of this monochrome handheld wonder, and later engines like NESticle for the NES spawned a legion of websites and discussion forums for interested people. Pretty soon more complex 16-bit consoles, arcade boards and alternative computer platforms were being reverse engineered to run in a 32-bit x86 environment.

Suddenly it was a conceivable notion to dump your SNES ROMS or Amiga games to images, pack the machines themselves away in the oft forgotten corners of your garage, and utilize your Windows machine for a quick round of The Great Giana Sisters. Armed with a soldering iron, ‘DirectPad pro’ drivers and nerves of steel you could even butcher your SNES controller to operate on the PC.

There’s no small sense of irony in the notion we’re going to such extremes to play games built for a 3.5MHZ CPU on an Intel Core2 Duo.

Alternative computer platforms dried up with the death of machines like the Amiga and Atari, leaving emulators like WinUAE as perhaps the only way to experience these legacy greats.

Metroid Prime, one of many reasons emulation rocks.

Consoles however continued to evolve in complexity and innovation; likewise the emulation community had to rise to the challenge of reverse engineering 5th and 6th generation consoles.

Emulating a relatively simple machine like the Gameboy (with its Z80 based environment) and getting it to run smoothly on far superior computer hardware is a far cry from tackling the custom architecture of the Nintendo 64 or Playstation.

Consider the PlayStation 2. On release it rivaled the best gaming technology any PC could offer, and to this day still presents challenges to those intrepid teams attempting to bring PS2 emulation to the desktop, despite modern Windows PC hardware being more developed than the aging console.

In a recent chat with ‘ZeroFrog’ – one of the senior developers from the PCSX2 PlayStation 2 emulator team – he described the older methods of coding emulators as being ‘unable to cut it’ for newer generation machines.

“The PlayStation 2 packs quite a lot of power under the hood, and a lot of engineering goes into the design of the algorithms.” He noted.

“The dynamic translators in our PCSX2 engine have to perform a lot of ‘magic’ not found in earlier emulators to achieve the desired performance. Self-modification of code during runtime, register graph coloring and juggling between SSE, MMX and regular x86 registers are just some of the things we’ve had to deal with…”

Nonetheless, these and other systems have been emulated with varying degrees of success, enabling programmers to delve into the intricacies of hardware abstraction, and nostalgic gamers to get lost in the delights of a bygone era without ever leaving the sweaty comfort of their computer desks.