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 ...
- 39.2k
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 ...
- 236k
23
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 ...
- 11.5k
22
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. ...
- 1,529
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 ...
- 236k
15
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 ...
- 266
13
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 ...
- 38.1k
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 ...
- 37.2k
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 ...
- 236k
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 ...
- 4,024
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 ...
- 236k
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 ...
- 4,024
Only top scored, non community-wiki answers of a minimum length are eligible