The other interesting thing about older hardware is that each cart could embed special hardware that the NES could take advantage of. To play those games: that extra hardware has to be emulated as well.
So far as I know: this is unheard of with current gen consoles.
The most recent example I can think of is for a handheld console. The Pokemon Walker that was bundled with the newer Pokemon games for the Nintendo DS; which I believe has the IR hardware embedded in the cart itself.
So in addition to worrying about rather interesting use of the stock hardware, you also have to consider interesting use of _secondary_ hardware.
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The latest batch of consoles [Xbox One, PS4] look to be x86 PCs with high-bandwidth memory; if that's the case, I'm hoping PC ports are more common, and perhaps we'll even see a virtualization based approach to running next gen games on standard PC hardware.
Well, modern consoles _could_ still be extensible; but their hardware is already so general purpose that there's not much point.
Best you could do w/ current gen technolgy is bundle a dongle w/ the game, where the user plugs in some kind of co-processor through USB.
So far I haven't really seen anything like that -- the only USB dongles I've seen bundled w/ games are for games like RockBand and they're just RF receivers.
Aside from bandwidth concerns, and the poor sales of previous attempts (for e.g the SEGA's whole 32x/CD addon), there's nothing preventing a disc-based from having an external co-processor.
So far as I know: this is unheard of with current gen consoles.
The most recent example I can think of is for a handheld console. The Pokemon Walker that was bundled with the newer Pokemon games for the Nintendo DS; which I believe has the IR hardware embedded in the cart itself.
So in addition to worrying about rather interesting use of the stock hardware, you also have to consider interesting use of _secondary_ hardware.
---
The latest batch of consoles [Xbox One, PS4] look to be x86 PCs with high-bandwidth memory; if that's the case, I'm hoping PC ports are more common, and perhaps we'll even see a virtualization based approach to running next gen games on standard PC hardware.