GB/GBc/GBa, DS/3DS (we don't talk about DSi) come to mind if you count them as consoles. You can even play GBa in the original DS, but not in the 3DS as far as I know.

DSi XL (LL) is actually my favorite way to play DS games because the screen is huge (and IPS!) but is in the native DS resolution of 256×192 pixels. DS games on 3DS-derivatives look like blurry garbage because they get scaled up to 320×240px for display on the 3DS's 800×240px (400×240px per eye) panel.

If you hold down the start button while booting a DS game then the 3DS will render it with 1:1 pixels instead of ugly scaling, but then you're not using the whole display so a DSi XL is still better.

I'm surprised there isn't a 3DS mod to bodge in a fancy modern panel with enough DPI to hit the lowest common multiple of those screens' resolutions, such that it can pull off a full-coverage integer-scaled mode for both DS and 3DS games. (There certainly exist enough mods that do this for GB/GBC!)

Would they still support autostereoscopic 3D, though?

I'd kill to see a New 2DS XL with this mod, however...

Now I'm curious if anyone has tried the 3DS XL?

The 3DS actually has a GBA CPU that was used when Nintendo gave some free GBA games away to early 3DS buyers after they lowered the price, as a sort of refund for the difference in prices. You can access it now buy jailbreaking your 3DS, but if you have a New 3DS, emulation on the main CPU is more convenient.

Similar situation with the Wii U. It was technically capable of natively running GameCube games, but Nintendo locked out the functionality. It can enabled with homebrew.

>(we don't talk about DSi)

New 3DS crying in the corner because it didn't even get a side mention, which about matches the number of exclusives it had.

In addition to supporting GameCube discs, the Wii had physical ports for plugging in GameCube controllers and memory cards. So, not much of a stretch.

The Wii Hardware was also basically a beefed up GameCube. Plus the Wiimote.

They even released a version of the wii without the gamecube ports or compatability (before the wii mini) which immediately supports gamecube games again if you solder the ports back on.

yeah and the DS had a GBA cartridge slot.

That's exactly what they called it when its internals became known: an enhanced Gamecube with waggle controls.

The graphics chip was even fixed-function, like the Gamecube's, not shader-based like the Xbox 360 or PS3.

> The graphics chip

The graphics architecture was even the same between Wii and GameCube - ATI's Flipper, just with 50% higher clocks on the Wii.

And in fact bug for bug compatible.

The Wii is pretty much a souped up Gamecube, hardware wise. the GPU, Hollywood (Wii) is a faster Flipper (GameCube). The CPU is an IBM PPC Broadwell, the direct successor to the Gekko in the GameCube. Memory, etc. The only difference is the controllers, really. And even then, since everything was external including the IR bar, there wouldn't be much preventing you from doing this on the GameCube. The very reason you can pop in a GameCube game in it and have it run without emulation is because... It's the same, but faster. Same thing that the Switch and Switch 2 will be.

Wii, Wii U, GBC, GBA, DS, 3DS all had backwards compatibility.

Technically, so did the SNES with the NES, it was just never really exposed. SMB all-stars started as SMB3 running directly on SNES. And you had the Super GameBoy, but that was little more than a GameBoy in a cartridge.

> Technically, so did the SNES with the NES, it was just never really exposed.

I've always wondered how true this is — I feel like if it was literally true, we'd see a lot of NES ROMhacks that involve editing the ROM's layout and metadata bits just enough that it's now a SNES ROM, and then taking advantage of SNES capabilities in the mod. But I don't believe I've ever seen something like that.

I do understand that the SNES CPU is basically a "very extended" 6502; and that the SNES PPU's default-on-boot graphics mode is compatible with drawing NES-PPU-formatted CHR-ROM data; and that there's a "legacy compatibility" joypad input MMIO in the right place in address space to allow a game that was programmed for the NES to read the "NES subset" of a SNES controller's buttons.

But is the SNES's (variant) 65C816 ISA a strict superset of the NES's (variant) 6502 ISA? Or would they have had to effectively go through the assembly code of SMB3 with a fine-toothed comb, fixing up little compatibilities in the available instructions here and there, to get it to run on the SNES?

(Though actually, even if they did have to do that, I imagine it would be still be possible to automate that process — i.e. it would be theoretically possible to write a NES-to-SNES static transpiler. In fact, it's so seemingly-tenable, that I'm a bit surprised to have never heard of such a project!)

> the SNES PPU's default-on-boot graphics mode is compatible with drawing NES-PPU-formatted CHR-ROM data;

SNES 2bpp tile format is actually identical to the Game Boy's format; iirc the difference from NES is that the bitplanes are interleaved instead of separate.

> But is the SNES's (variant) 65C816 ISA a strict superset of the NES's (variant) 6502 ISA?

Mostly yes, the biggest exception being the infamous illegal opcodes which a few NES games did use. The other being that decimal mode actually works.

The main challenge in porting a game from NES to SNES would have been with the wildly different PPU and audio systems.

> it would be theoretically possible to write a NES-to-SNES static transpiler.

For simple games, static translation might be possible, but later era NES games' widespread use of cycle-timed raster effects and bank switching mappers makes it more complicated. (You could theoretically put such a mapper in an SNES cart too, but nobody did that.)

There's at least one such effort, Project Nested: https://github.com/Myself086/Project-Nested

The Sega Mega Drive (Genesis) had backwards compatibility with the Master System. Unlike the Super Game Boy, the Power Base Converter was barely more than a cartridge pass-through adapter. The Mega Drive’s 68000 is idled and its Z80 sound co-processor takes control as the main CPU.

https://segaretro.org/Power_Base_Converter

It's not a "stretch", it is exactly that. It's widely known by anyone familiar with the hardware that Gamecube and Wii are basically the same console: it's the exact same architecture but the Wii has upgraded/faster components and (this whas the key:) different peripherals and bet on the motion controls. It's more or less like comparing the Intel 386SX with 20 MHz and the AMD 386DX with 40 MHz.

You could just ask the developers of Dolphin (Gamecube/Wii emulator). There's a reason for why the same emulator can emulate both consoles.

Incorrect. The Wii is far more similar to the Gamecube than the WiiU.