Modding the N64 - Anyone know how?

[Karny]

I've got a PAL N64, but I've recently started buying NTSC games (Some Jap, some US and some Asian ones, which might be PAL).

I have a converter catrifge, but it doesn't work at all, I can only assume it was designed for NTSC machines.

Its there a way to modify my N64 to allow me to play these new games, or do I need to buy a new machine to play the games from each region, I'd really not like too have to buy 3 new N64's...

 

[CrowTRobo]

What you would want is the 'N64 Passport 3' which lets you play any game on any n64. You plug in a native cart into it (for you, PAL) and then plug the import cart in the other slot. It will use the bootcode from the native cart, but will play the import cart.

I've read about some problems with it, not exactly sure what they are, but it (and other converter carts) are the only option besides buying a US/Japanese N64.

CrowTRobo

 

[CrowTRobo]

BTW, you would only need 2 N64's. The US/Japanese systems will play each others games fine. You just got to rip out two plastic tabs inside the system, which prevent the import cart from being inserted.

CrowTRobo

 

[Karny]

Okay, thanks for that... 2 more questions then...

Where and how much for Passport 3?

And should I rather just get a US N64? Whats the going price on a second hand one?

 

[ExCyber]

/me wonders why someone apparently hasn't figured out how to disable the CIC in the N64 to create a "universal" system.

 

[herrgafgarion]

ummmm a used N64 in the US goes for about 40 maybe even 30, shipping is going to be a bitch for you though

 

[CrowTRobo]

Where and how much for Passport 3?

A lot of online stores have it, especially all the HK ones like Lik-Sang, Goldenshop, Daves Console Store, etc. I think it goes for around $20.

And should I rather just get a US N64? Whats the going price on a second hand one?

Hmm, not really sure. I doubt you will find one for $20 which makes the Passport cheaper. But I can't see one going for more than $30-$50. If you have the money, it might be worth it to get one and not deal with the Passport?

CrowTRobo

 

[imported_Arakon]

all newer games (i.e. of the past 2-3 years) also have a 50/60 Hz check. no cart gets around that one, nor can you modify the n64.

 

[ExCyber]

I'm pretty sure that there are carts that use Gameshark-like functions to patch 50/60Hz checks. I think the Passport III is one of them, but I haven't looked into that lately. Chances are that it needs to have new codes entered for different games.

 

[CrowTRobo]

me wonders why someone apparently hasn't figured out how to disable the CIC in the N64 to create a "universal" system.

Well, I know someone who made a "universal" cart by putting in a socket for the CIC chip, which allows him to swap in or out any CIC chip he wants.

Now, as you probably know, I'm a software guy and don't know much about inner workings of hardware. But AFAIK, there isn't anything in the N64 to disable. The bootcode is in the cart and is what will prevent a game from running if the CIC chip doesn't match what it expects.

CrowTRobo

 

[CrowTRobo]

Well, actually, there might be. When you boot the N64, the first thing that gets executed is code in the PIF ROM. This sets up all the registers, etc like putting the value of the inserted CIC chip into register 22 which then the bootcode uses as a seed in it's checksum algorithm. I think it also puts the NTSC/PAL info somewhere (I'm a little rusty with the N64).

So if someone could install their own replacement for the PIF ROM, then maybe it could be possible? I'm sure it would be complicated though.

CrowTRobo

 

[ExCyber]

Well, the CIC scheme on NES and SNES works by having a "lock" chip in the system that communicates with the "key" chip on the carts; from what I've read, these are simple microcontrollers that run a program amounting to a pseudo-random number generator with a fixed seed number. The "lock" holds the system (or some essential part of it, such as the PPU) in a reset state until it verifies that the connected "key" is generating the expected number stream. I had assumed that the N64 scheme is similar, since it won't run even homebrew stuff (which presumably wouldn't check for the presence of a CIC) without a CIC connected.

 

[CrowTRobo]

With the N64, it's all about the checksum. If the checksum isn't correct, the N64 will not run the program. And that's what the CIC chips are for. They contain a seed, which is put into a register, then the bootcode in the ROM does it's checksum algorithm using this seed. So obviously, if there is no CIC chip present, it will not get the correct result. It will also not get the correct result if the CIC chip is different.

That's what bootemu's do, they init the N64 just like the PIF ROM does and puts the appropriate value for the game you want to run in the seed register. Once it was figured out, it was quite easy. (BTW, I didn't figure it out, just to be clear). But with my CD64 util, adding the ability to run non-6102 games and include automatic country fixing was not hard at all.

CrowTRobo

 

[ExCyber]

I understand that the checksum needs to be correct. I am not disputing this. What I'm disputing is that the checksum is the sole protection provided by the CIC. If that were true, someone would have figured out by now how to make ROM emulators that don't require a cart to be plugged into them to run. There has to be some type of protection more fundamental than the checksum routine. Either that, or there's something you're not telling me about it that makes the actual contents of the ROM irrelevant to the procedure.

 

[CrowTRobo]

Well, after our discussion last night, I think we can both say we really don't know what the hell Nintendo did exactly or their mindset when it came to N64 protection.

CrowTRobo

 

[Karny]

K, I'll get a US N64 then