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38 votes
Accepted

Why did the Z80 break 8080 compatibility?

The designers of the Z80 thought it would be useful for code to quickly determine whether signed arithmetic operations overflowed. There were a few ways they could have accommodated this: Add a new ...
supercat's user avatar
  • 36.3k
30 votes

Why did the Z80 break 8080 compatibility?

Would providing full 8080 compatibility have interfered with or made more complicated implementing new features the Z80 designers wanted? It would have made it impossible. Any extension adding ...
Raffzahn's user avatar
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22 votes
Accepted

Why did the PlayStation 2 implement backward compatibility that way?

Probably because it was the only way to get 100% compatibility with the old software library, which was required while most PS2 titles weren't developed yet. No one wants to buy a machine without ...
Jean-François Fabre's user avatar
21 votes

How much PlayStation 1 hardware in the PS2?

Calling it an emulation might be selling it under value. There is way more upward compatibility included than just software. Essentially the PS2 contains a full PS1 subsystem sans the GPU. It might be ...
Raffzahn's user avatar
  • 224k
21 votes
Accepted

What was the first console to have temporary backward compatibility?

The Mega Drive/Genesis is the obvious answer, but I can also make a case for the earlier Master System. Initial models were fully compatible with Sega's prior console, the somewhat obscure SG-1000. ...
Matthew Barber's user avatar
16 votes
Accepted

Is the NES controller port identical to the port on a Wii remote?

The two consoles do have different controller ports. The NES Classic Edition is not directly compatible with original NES controllers, but it does work with the Wii Classic Controller. The original ...
libertyernie's user avatar
12 votes

What was the first console to have temporary backward compatibility?

The Mega Drive 1 and 2 can run Master System software via the Powerbase Converter. Neither the Nomad (the portable Mega Drive) nor the Mega Drive 3 are capable of doing so without further internal ...
Tommy's user avatar
  • 36.9k
5 votes

Why did some BIOSes have the timer tick wrap around at 1800B1h instead of at 1800B0h?

In short, it might be for avoiding the same value for copyright reasons, or simply because some BIOS vendors calculated the value with a timer frequency value that has more precision than what IBM ...
Justme's user avatar
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2 votes

Why did the PlayStation 2 implement backward compatibility that way?

But the chosen method is actually rather extraordinary when you stop and think about it. But neither new or unheard of. The 1986 Apple IIgs, 8 years before even the PS1, already included a single ...
Raffzahn's user avatar
  • 224k
2 votes

What was the first console to have temporary backward compatibility?

The Nintendo consoles were generally not backward compatible between different models NES->SNES->N64->GameCube. The exception being the Wii, which could play GameCube games, and the Wii U, which could ...
Mark Williams's user avatar
1 vote

Why did some BIOSes have the timer tick wrap around at 1800B1h instead of at 1800B0h?

Maybe some points to considere: Was this a wide-spread phenomena for which one should take precautions when creating algorithms that convert the tick count into the corresponding time, so as to avoid ...
Raffzahn's user avatar
  • 224k
1 vote

What was the first console to have temporary backward compatibility?

Both the Amstrad CPC series of machines and the Sinclair Spectrum exhibited backwards compatibility. The Amstrad CPC 464, 664 and 6128 were each compatible with their predecessors, as were the ...
Mark Williams's user avatar

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