During E3, Microsoft dropped a bomb and announced that they would be including a backwards compatibility feature in their next-gen gaming platform the Xbox One – something many wanted from the start. The company said they are releasing the new feature free of charge in the fall. One of the reasons that this didn’t happen sooner was because Microsoft was researching efficient ways to deal with the CPU differences between the two consoles – IBM PowerPC (PPC) on the 360 vs the AMD Jaguar on the Xbox One.
So how can all this happen if the CPU architectures are different? One word, – virtualization. Microsoft has built a virtual Xbox 360 and ported it over to the Xbox One. The Xbox 360 games will run via software emulation – which allows for the “emulation” of another computer system. As far as the game is concerned, its running on an Xbox 360. Microsoft has left in all the details that you would expect when using your Xbox 360 – notifications, Xbox Guide and even achievements. The Xbox One essentially treats the virtual Xbox 360 as an app – allowing features like screenshots and video sharing.
One of the concerns with emulation has always been performance. Will a game run just as good as it did on its original hardware? The answer is mixed, as there are some games that run really well and others that do not. The emulation used for the Xbox 360 isn’t with without its share of performance woes, as seen in this video from DigitalFoundry showing the game Mass Effect running on Xbox One backwards compatibility vs running natively on the Xbox 360.
While performance is definitely a concern, the software should be able to run most games without issues. To be fair, Microsoft is still working on some finishing touches.
Other caveats include hardware limitations – essentially games that use additional hardware peripherals won’t be supported. In addition, multi-disc games are not supported at this time however, Microsoft is currently working on this and expects it to be available at some point.
Still, Microsoft expects to have over 100 titles at its holiday launch later this year and most people are excited about the new capability.