Gaming Q about the 3DS's DS mode

[Lucifer666]

Hey guys.
I've been thinking..
When you open up a DS game on the 3DS, all 3DS features are disabled, right? (You appear offline to friends, Wi-Fi is switched off if you're playing offline, no spotpass, no streetpass, etc.)
Alright, but what confuses me here is when you hit the 3DS home button while in a DS game.
That little menu shows up, which I find totally weird.
I mean, to begin with, DS mode shouldn't even be able to recognize the home button since that doesn't exist on a DS.
Another thing is that the little menu that shows up is clearly a part of the 3DS's OS or 3DS mode.
I know I've totally gotten this really misunderstood, so I'd appreciate it if someone could maybe explain how that works.

Thanks!

 

[Slyakin]

When you press the Home Button, the DS game is temporarily paused (think DS's Sleep Mode). The 3DS is then technically in 3DS mode, as you can alter brightness and power save mode.

The DS game itself doesn't recognize the Home Button.

 

[Lucifer666]

The DS game itself doesn't recognize the Home Button.

Exactly my point. I mean.. IIRC, DS mode is basically an actual DS, so if the home button was to be pressed, how does the 3DS itself react, when really it's a DS at that moment?

 

[Slyakin]

I'm pretty sure that the DS mode is emulated in a sense, so that the 3DS can still take input from the Home Button.

I'm not too informed on this topic though, so I can't help too much. Sorry about that. :/

 

[Demonstryde]

The DS game itself doesn't recognize the Home Button.

Exactly my point. I mean.. IIRC, DS mode is basically an actual DS, so if the home button was to be pressed, how does the 3DS itself react, when really it's a DS at that moment?

the 3ds is a nds emulator think of it that way... its like the start button on your windows pc,,no matter what game you are playing or programm you can hit the home button and it brings up the start menu

 

[Lucifer666]

Mhm, so if I'm not mistaken, it kind of works like the Supercard's real-time menu..
That's really interesting.
I wonder if 3DS features were to be accessed by some sort of DS mode homebrew..
edit: I totally herped up a bunch of rubbish. I think I finally understand now.
Thanks both of you.

 

[Pippin666]

Is not the DS game that picks up the HOME button, it's the system. It's so more simple said that way.

Pip'

 

[DiscostewSM]

DS games are not emulated on the 3DS, but more likely set up in a virtualization mode.

Besides, I'm pretty sure if it were emulated, then battery life would be far less playing those than actual 3DS games.

 

[Spidey_BR]

Is not the DS game that picks up the HOME button, it's the system. It's so more simple said that way.

Pip'

The Home Button probably just interrupts the cpu and then you get that "pause" screen.

 

[koji2009]

DS games are not emulated on the 3DS, but more likely set up in a virtualization mode.

Besides, I'm pretty sure if it were emulated, then battery life would be far less playing those than actual 3DS games.

This. It's virtualization and not emulation.

Basically there are 4 ways nintendo could have handled things the way they did... Emulation, virtualization, native, or hardware locking.

Native would be a DS game running as if it were a 3ds game. Nintendo wouldn't do this because of the fact that the original DS protection is terribly broken and it would be have a negative impact on compatibility (running games too fast, broken timings, etc)

Emulation would require software (everything, or at least almost everything done via CPU) translation of all CPU/GPU/Timings/etc. This would be needlessly complex and a very big battery drain and may not even be feasible given how little we know about the 3DS' true hardware. It also leads to unnecessary compatibility issues (since the hardware is so similar anyways)

Hardware locking would be much like how the Wii plays gamecube games... It basically restarts the system in a 'compatibility' mode where the Wii hardware is locked out and the GPU/CPU are underclocked to match the cube. Theoretically perfect simulation, but then lacks all wii features.

Virtualization is thus the best choice and is kind of a combination between the two above methods. Both the hardware and software have to be designed with it in mind... The software basically sets up a "computer in a computer". The innie (in this case the DS) lacks any ability to interact with the outtie (in this case, the 3DS) while the hardware is designed to be able to split work between the two tasks. This allows you to have an actual 3ds menu while playing DS titles... While without the system being hacked to be sure, we can assume that the reason why most of the regular 3ds features are probably disabled to insure proper timings inside the VM DS, or that certain features of the CPU which are necessary for certain other functions (like wifi controller on DS) are locked to the VM so there is no resource conflict leading to an ugly screen of death.

 

[Lucifer666]

DS games are not emulated on the 3DS, but more likely set up in a virtualization mode.

Besides, I'm pretty sure if it were emulated, then battery life would be far less playing those than actual 3DS games.

This. It's virtualization and not emulation.

Basically there are 4 ways nintendo could have handled things the way they did... Emulation, virtualization, native, or hardware locking.

Native would be a DS game running as if it were a 3ds game. Nintendo wouldn't do this because of the fact that the original DS protection is terribly broken and it would be have a negative impact on compatibility (running games too fast, broken timings, etc)

Emulation would require software (everything, or at least almost everything done via CPU) translation of all CPU/GPU/Timings/etc. This would be needlessly complex and a very big battery drain and may not even be feasible given how little we know about the 3DS' true hardware. It also leads to unnecessary compatibility issues (since the hardware is so similar anyways)

Hardware locking would be much like how the Wii plays gamecube games... It basically restarts the system in a 'compatibility' mode where the Wii hardware is locked out and the GPU/CPU are underclocked to match the cube. Theoretically perfect simulation, but then lacks all wii features.

Virtualization is thus the best choice and is kind of a combination between the two above methods. Both the hardware and software have to be designed with it in mind... The software basically sets up a "computer in a computer". The innie (in this case the DS) lacks any ability to interact with the outtie (in this case, the 3DS) while the hardware is designed to be able to split work between the two tasks. This allows you to have an actual 3ds menu while playing DS titles... While without the system being hacked to be sure, we can assume that the reason why most of the regular 3ds features are probably disabled to insure proper timings inside the VM DS, or that certain features of the CPU which are necessary for certain other functions (like wifi controller on DS) are locked to the VM so there is no resource conflict leading to an ugly screen of death.

Wow. Haven't seen a more helpful and informational answer yet.
All the confusion's gone, thanks m8.

 

[altorn]

actually, i think the DS mode should take lesser battery than 3DS mode because the CPU is pretty much underclocked and most of the power consuming features (especially the top screen, which will be taking less resolution).

but pretty much koji has the best answer so far.