How do games detect flashcarts?

Discussion in 'NDS - ROM Hacking and Translations' started by HoTsHoT89, Feb 28, 2010.

  1. HoTsHoT89
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    HoTsHoT89 GBAtemp Regular

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    So as most R4 users are still waiting for a patch for a certain racing game, it never dawned on me on how games with piracy protection could detect flashcarts.

    Most of us have probably experienced various forms of protection, like 'traps' in certain parts of the game (Chrono Trigger DS), unable to save (GTA:CW), or even unable to boot completely. To the DS console, isn't a flashcart a normal game card to them? I'm certain those games have lines of codes to check something, but what, and how exactly?

    As for bypassing the protection, we have cheats which is patched into the game ROM which allows the piracy check to be bypassed or circumvented. I have a rough idea on how it works, but it's definitely better to know more.

    Answering these might require a degree of technicality but it would be very helpful if you guys could get down and dirty. [​IMG]
     


  2. Jakob95

    Jakob95 I am the Avatar

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    Most of the time threw the sav files.
     
  3. YayMii

    YayMii hi

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    BTW, GTA: CW doesn't have anti-piracy. It just has a bigger save that wasn't compatible with flashcarts at the time.
     
  4. Normmatt

    Normmatt Former AKAIO Programmer

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    Yes it did, it used a standard size 64kb save. Stop spreading bullshit.
     
  5. HoTsHoT89
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    HoTsHoT89 GBAtemp Regular

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    I did remember that GTA:CW's piracy protection was implemented at the save.

    But that's not the point. What I'm really interested is how do games do checks to know if the DS is using a flashcart. I'm speculating checks are done in the DS memory after the game has been loaded in, but if the DS console reads the flashcart as though it was a normal game card, shouldn't there be no problems?
     
  6. rockstar99

    rockstar99 Hi

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    sheesh... no need to be so rude to the guy
     
  7. Demonbart

    Demonbart GBATemp's guitar hero

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    AFAIK the cheat systems on flashcart use cheats in a way that's different from the actual Action Replay. Games detect this, and block the game. That's why clean mode on Supercard/Cyclo might help solve your problems, and it's also why R4 users are permanently fucked, since R4 doesn't have a clean mode, and there aren't any official firmware updates anymore.
     
  8. Overlord Nadrian

    Overlord Nadrian Banned

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    He has a point though, a lot of people just post crap they don't know anything about and say it's true.
     
  9. Megaman0

    Megaman0 Member

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    Still it's not like someone would say it like that if they were face to face. There's no need to be rude just because it's the Internet. Especially if he really believed that GTA: CW has a bigger save...
     
  10. CannonFoddr

    CannonFoddr Regular GBATemp Lurker

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    How on earth did we get onto whether GTA:CW got AP or not when the poor OP asked
     
  11. metroid4life14

    metroid4life14 GBAtemp Fan

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    I've actually wondered this as well. I always assumed it was something that happened through the dump process, but after reading these posts, I guess not
     
  12. HoTsHoT89
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    HoTsHoT89 GBAtemp Regular

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    Aren't ROM dumps always 'clean' in a sense, that they are unaltered and as-is from the original game cart? Most users can't even play clean ROM dumps without encountering some kind of stopgap. Cheats or not, the piracy protection exists.
     
  13. choconado

    choconado Doesn't understand a damn thing on here

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    yeah wait, it CAN'T be in the cheats, because there's still lots of gamers that don't use them and still hit the AP wall. Maybe someone who has real firmware/patching programming experience can pipe up? Normmatt? You're clearly reading the thread, and I assume all that work on AKAIO would give you some sort of clue...
    Where the hell does the AP stuff check?
     
  14. Normmatt

    Normmatt Former AKAIO Programmer

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    Wrong again!

    They do reads below 8000h which on official games still be redirected to 8000h in the rom while on flashcarts it isnt redirected and as such its easy to see its a flashcart, its not a simple fix either though, as the checks use their own read card function which isn't patched and as such reads need to be quick which they aren't unless the routine is patched [​IMG]
     
  15. CrashmanX

    CrashmanX Current project: SD Gundam G Generation Overworld

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    Uh, no? I've never heard of the Cheat System being the issue, if that were true people would just make a Cart w/o cheats. There are sometimes things on the flash cart itself that can give away what it is, other times its something completely different. Most games use similar AP but some games use different AP, it all depends.
     
  16. Ammako

    Ammako GBAtemp Guru

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    To be fair, Anti-Piracy measures alerady existed in the Super NES era.
    Just look at Earthbound.

    Earthbound looked at sram space. If there was more space for sram than usual, the game would make a lot of enemies appear. This made the game unplayable.

    Every game has a different Anti-Piracy system, though they all get cracked quite fast.
     
  17. SickPuppy

    SickPuppy New Member

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    Why do the patches only work on certain flashcarts? Exapmle: I patched a certain racing game and it worked on one flashcart, but not on my other two flashcarts? I am running the latest firmware on all three flashcarts.
     
  18. Normmatt

    Normmatt Former AKAIO Programmer

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    Because not all flashcarts patch the game in the same way. Not to mention some flashcarts just plain suck ass.
     
  19. YayMii

    YayMii hi

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    *Post removed*
    Just realized I was flaming. I removed it to avoid the banhammer [​IMG]
     
  20. CrashmanX

    CrashmanX Current project: SD Gundam G Generation Overworld

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    Odd, I heard that with Earthbound (or else it was Mother 1,2, or 3) that you could play the entire game until the end where right before the ending it game you a "THIS GAME WAS PIRATED" screen and deleted your save data.