N64 PAL/NTSC Possible ?

Discussion in 'Modding and Hacking - Consoles and Electronics' started by emu_kidid, Jul 7, 2008.

  1. thetoillmainn

    thetoillmainn Newly Registered

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    Ah, yeah. I guess what I thought would have been too easy or someone would have done it already. But wouldn't it be possible to program a chip to do something like that? Exactly like the other modchips work by making it believe it's running a licensed game.
    Anyways, thank you for a fast reply!
     
  2. splith

    splith Resolute Member

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    I'm unsure of how the N64 CIC works, the SNES and NES systems worked by just checking for a signal and then making a pin go from high to low which enabled the CPU. The N64 version could make use of cyphers and encryption or whatnot, so you'd either need to find out how the chip worked or get the schematics for it.
     
  3. marshallh

    marshallh N64 Coder

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    On boot, the PIF inside the n64 starts sending a very, very long sequence of random numbers to the CIC. The PIF is always reading the response back (this is a continuous process while the N64 is turned on).

    Once the PIF is happy with the values it's getting back, it releases NMI on the R4300. This causes an NMI interrupt on the cpu, and causes it to start executing code from the memory location 0xBFC00000. Because all the memory is accessed through the RCP, this small segment of memory is mapped to a small almost 2k chunk of ROM in the PIF called PIF-rom.

    The code in there is r4300 executable code. The actual boot process is pretty convoluted, that's another time. But about halfway through the sequence of boot programs, the R4300 reads from PIF ram (small 64byte area) and this contains values used in the calculation of the CIC seed. (6102 seed is 0x3f)

    The way a game determines whether it's running on a PAL or NTSC console is simple - it's hardcoded in the PIF rom.

    If you have a logic analyzer and some tools you can put probes on the lines that go from the PIF to the RCP and catch all the contents of the pif ROM as it's read. This is the only way to get access to it, because after the boot process you will read all 0's from where the PIFrom used to be mapped.

    Once you have it dumped you can look for the instruction that loads the register s4 (something like li s4, 0x01) and change it to 0x0 for PAL, and 0x1 for NTSC.

    You can also use a boot emulator to do all this, but it means you have to have a way of running your own code. The boot emulator basically runs a version of PIFrom that is hacked to skip the security checks, and you patch in whatever values you want (you can fake different CICs and regions this way)

    The CIC seed is also used to checksum the bootcode in the first 4k of game ROM, and to also checksum the first 1MB transferred to make sure the cart interface is reliable.
     
    Last edited: Jul 5, 2010
  4. raylyd

    raylyd Guest

    how about useing seb code switchless mod useing the reset buttion would be cool
     
  5. FritoFredrik

    FritoFredrik Member

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    Now i do not like that you need 5 switches (ore even more) to do this
    so why not just make the 2 different PIF-NUS chips in like a little cartridge
    that you can change out if you want to play a game from another region

    Did this in google sketchup for fun::thumbsup: (just need a case for it)
    [​IMG]

    now will this work or did i do something really wrong?
     
  6. rso

    rso Gone. See y'all elsewhere, maybe.

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    There seems to be a misunderstanding - You don't use separate switches for each one in the diagram, you only need a single one that switches five contacts at once.

    Can't see why your idea shouldn't work though, but it'd be a helluva lot of very unnecessary work, and probably with pretty ugly-looking results imho.
     
  7. biscuit

    biscuit Rising Member

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    Two MC14551B ic's and 1 spdt switch then ?
     
  8. mca

    mca Member

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    what about running ntsc game on a pal console using passport III. Will it be 60 hz?
     
    Last edited: Mar 6, 2011
  9. bart_simpson

    bart_simpson Dauntless Member

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    Why not a switchless mod via reset?
     
  10. wmj

    wmj Member

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    Here's a picture of the inside of my N64. I bought it already modded with the region switch from http://www.otakus-store.com/. They sell a lot of modded consoles and also do a lot of modifications so maybe they know how this mod was done. It works 100% for all games, even PAL Perfect Dark works perfectly.

    [​IMG]
     
  11. Ho-Oh.x7

    Ho-Oh.x7 Member

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    As far as I'm aware the refresh rate is determined by software settings so NTSC games should run at 60 hz. If you load an NTSC game on a PAL console with an Everdrive or other backup device they run at 60hz. Some games will have audio errors because your using the wrong PIF chip.
     
  12. FireAza

    FireAza Shake! Shake!

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    Does the refresh rate change too? I'd be very interested to know how it was done if so!
     
  13. Bad_Ad84

    Bad_Ad84 The Tick

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    Region is set via a very complex method that isnt cracked (i.e. a replacement chip, like the supercic). You would need a way to give both types of PIF responses to the console. Which is why people are installing both chips.

    Now you could install both chips, install some solid state switching and then control them via a switchless mod, but its no where near as simple as you are making it sound.
     
  14. marqs

    marqs Member

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    That looks a lot nicer than the mess inside my N64:

    P1000316.JPG
     
    Last edited: Aug 31, 2012
  15. omp

    omp Familiar Face

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    I asked this in another thread similar to this one.

    What is the thought of installing the "key" from a game into the console permamently? IE disable the cart lines.

    It would be similar/same as using one of those piggy back adaptor carts.

    I was going to attempt this, I have both PAL and NTSC boards, but I was going to try and make one of the PAL boards region free.

    Reading this makes me believe it is easier just to set up both types of consoles lol!
     
  16. Bad_Ad84

    Bad_Ad84 The Tick

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    There are different "keys" so some games wouldnt work.

    There is only 2 locks - PAL and NTSC.
     

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