The DS's equivalent of 'Crooked Cartridge'

[Torchickens]

Usually when you pull the cartridge out while a DS game is still running all processes will instantly freeze, I wanted to experiment how this works in sleep mode and I found the following effect for pokemon platinum I did the following:

1) Load the game up
2) Close the DS lid and put the game into sleep mode
3) Quickly take the game out and back in again, if you do not do this quick enough the DS will turn itself off

So I go and walk to the left and the game instantly locks up however the fact the game did not lock up instantly gives me the theory that sleep mode simply resumes ongoing processes in the game by storing them in a temporary area it is notable that for the fraction of a second that the cartridge was out the music stopped but when i put the game back in the music continued again along with all the other npcs with their ordinary movement.  Since the game locked up when I moved left it must have tried to read some sort of coordinates byte and since it could not longer read any near information it must have locked up.

After finding this on pokemon platinum I attempt Super Mario 64 DS and the trick worked with that game too! While attempting to enter the castle as soon as Mario touched the door the game froze as if the game couldn't read the location byte. Finally I attempt the game's ingame debug mode (L+R+left+A let go B+down let go select+start.) and that worked suggesting that the game is still going on, it just can't read new bytes and the system's debug menu must be loaded as soon as the game starts.

[tachi]

hey I can't try that on my emulator!

[Mutou Yami]

Emulators, don't have cartridge slots. Emulators aren't like normal DS's.

[tachi]

That's kind of the joke Mutou...

[Mutou Yami]

It wasn't even funny. What you said about the DS Sleep Mode, sounds quite strange, where the DS is in like a stand-by mode, yet seems to like run the game. Crazy.

[Torchickens]

It is kind of like that, when you go into sleep mode it must store all the current information in a temporary area for later and when you put the DS lid back up it will resume that information and won't take up much battery memory because it only needs to store that particular information and when you resume the game new bytes can be read with the game cart.

But since in this instant you have taken the game cart out and back in even though the game cart is in the DS still can't read it because it hasn't initialised with it (it seems to do this when you turn the power on so that the game appears on the DS menu) but the game will carry on because it knows the cartridge is back in but it doesn't 'know' that it can't be read. If you leave the cartridge out and do this the game will simply switch off.

The reason why with a short time of taking the cartridge out and back in the game can resume seems to be more techincal; if you turn the mains plug off and instantly turn it back in everything will resume, that seems to be why if you have a lightning strike sometimes everything will switch off and resume instantly. The DS must have a system like this but in this instance with sleep mode where if the game is out for more than about a second the power will turn itself off which happened a few times but anything less the game will resume but not function right because it can't read anything more.

[Mutou Yami]

That's pretty interesting. Nice job.

[Torchickens]

I just tried it with Rayman DS and that is definitely not stable; when I move to another level the description is some glitched pink blocks there is a lot of static in the background to replace the music. Bombs in the background in one part of the map explode into pink fuzz. Finally when you enter the level the game will just lock up.

[The Kazuka]

I just tried it with Spectrobes and everything seemed fine...until I left the ship...or talked to Jeena.  Whenever I did that, it froze.  I think I'll try it in battle now, just to see what happens...

[Zowayix]

I might test this with some of the games I have when I can be bothered. Sounds like it might have interesting results.

[Jolteon]

Darn it, my reactions aren't quick enough to do this.

[Zowayix]

Kirby Super Star Ultra: Tested in Spring Breeze, game worked normally until I walked through a door at which point it froze trying to load the map data.
So yeah, this does require fast reflexes x_x
EDIT: Tested the rest of my games (that weren't already tested by Torchickens) because I could:
Cooking Guide: Tested with the potato wedges with sour cream recipe. Timer stopped at 23:42, "game" froze upon trying to continue cooking instructions.
WarioWare: Touched!: This one was pretty much expected really. Tested using the Monster Megamix, game successfully unpaused (microgame was the wave goodbye one), game froze upon trying to load a new microgame.
New Super Mario Bros.: Tested on first level (not a new save file, which probably made no difference), game functioned normally until attempting to return to the map after clearing the level at which point it froze.
Kirby and the Squeak Squad: Tested on first level, game froze when I tried to get the Beam ability.
Pokemon Mystery Dungeon Blue: Lol, this game is too clever for its own good. Tested in Tiny Woods, when a Wurmple attacked me a message box appeared saying "The Game Card was removed. Turn off the power, reinsert the Game Card, then turn the power back on."
Pokemon Mystery Dungeon 2: Explorers of Darkness: Tested in Beach Cave, same as above (without the Wurmple).
Pokemon Ranger: Shadows of Almia: Tested in Haruba Desert, game froze immediately after opening the lid (this could be due to the sandstorm effect though).
Pokemon Ranger: Shadows of Almia (in battle): Tested against a Magneton in said desert, game froze when I drew a loop around it.

[Gawaxay]

Nice find Torchickens! Maybe if someone were to come up with a cartridge emulator where you could click and drag the cartridge...

[Torchickens]

Thanks, good idea! That would probably work. Are there any emulators which have sleep mode built in them? The only problem with an eject button is that the emulator would probably just reset the game and run it as normal when you load the ROM again so it would probably need some kind of stop reading new data mode which it uses temporary data that is already running, I think that is how sleep mode works.

[Gawaxay]

Thanks, good idea! That would probably work. Are there any emulators which have sleep mode built in them? The only problem with an eject button is that the emulator would probably just reset the game and run it as normal when you load the ROM again so it would probably need some kind of stop reading new data mode which it uses temporary data that is already running, I think that is how sleep mode works.

It was kinda a joke...what I meant was like it emulates the actual cartridge and you can click and drag to move the cartridge...anyway, maybe if you could get an emulator that had sleep mode and keyboard shortcuts for reset and sleep mode, you could do sleep mode then quickly reset...wait, no, because reset is turning off then turning back on. Well then maybe if the emulator also had a feature that simulated removing the cartridge.

Edit: Hmm, so to do this on an emulator you'd need a Stop Reading Data feature.