gc-forever - Gamecube/Wii Forums

Will do as soon as I get home tonight, about 6 hrs from now? If it works thats pretty awesome man. Whats the trick?

It works perfectly and WBFS manager says it takes up 0.0gb's lol... Tell me all your secrets

It works??? Tell me all your secrets 2!!

removing the unused zero's? :p

Tell me 3!

Well it is not a secret at all.

The Wiikey Fusion(->wkf) guys used it and I just used my hexfile editor to do the same.
But let's start with what I (and probably some other people) noticed:
- When we use a gamecube iso image on a wbfs sd card with wkf, the gc/wii resets and the wkf then loads the image.
- The wkf update discs act the same.
- When we add a gc iso image to the wbfs manager, it will take 1,36 gb regardless of the actual size, but a wkf update disc will only take 2 mb.

Have you ever opened a homebrew gamecube iso with a program like 7zip? You can view the files inside, because the iso file follows the ISO9660 standard.

I wondered why i couldn't open a wkf update disc in 7zip and looked closer at the ISO9660 file signature, which is "43 44 30 30 31"(hex) or "CD001"(ascii), also called magic word.
This signature usually occurs at byte offset 32769 (0x8001), 34817 (0x8801) or 36865 (0x9001) (said here).

So I opened a wkf update disc iso and a swiss iso with my hexfile editor and looked at the three adresses given. The swiss iso says "CD001", whereas the wkf iso only has empty bytes at these adresses. I searched for the string and found out that the wkf iso includes them at 0x108001, 0x108801 and 0x109001 which is exactly a 1mb gap to the standard.

The attached picture shows this. If you look at it you may notice that the content after the first 1 mb of the file will much look like the swiss iso. So I removed the first mb of the iso file and now 7zip successfully opens it and reveals the "FLASHERz.dol" which will update the wkf (nice to save this to sd card for update through swiss/sdload).
When I tried to add the cut wkf image to sd card via wbfs manager it will take the usual 1,36 gb.

So what is this first mb of the iso all about?
It may be easy: I think it is to trick the wbfs manager. Because it uses the wii disc magic word (0x5D1C9EA3, marked red in the attached picture) and not the gc magic word (0xC2339F3D, also marked), wbfs manager will add it like a wii disc.
It begins with disc header stuff (id, region, etc.) = first bytes (GWKP15). Then the disc title. The rest is zero fill bytes.
(For information on the disc structure look here)

What I did to create the test iso for Ashen
It's easy: Create a swiss iso and add the wkf iso header. (Okay I changed the disc id and name, but that's it)

Question: "Can we use these information for adding gc images to our wbfs drive?"
No, in fact not yet.

Let me tell why:
Because it is only a faked wii header, that the wkf team added to the images, the wbfs manager won't identify the file size and structure of this disc. So it will (speculation! ) use the smallest size available, which is somehow 2 mb. I tried it, it will only add 2 mb. Maybe if we fake the header a little more to include the file size, it works.

Took quite a while to write this post, didn't want to write a bunch of crap though. I hope it is not too technical.
If there are questions just ask.

I'm not done with this whole thing yet... and there is another interesting feature of the wkf I will look at.

Good stuff!! What does the wiikey team have to say about this? Anybody contact them about the image size issue?

Have you tried to compare the faked wii header with a original wii game? Wonder what the difference would be.....

you can't use the fake header on shrunk GC games (but you can for homebrew gcm files) because the games wouldn't be able to find their memory card files you've created before, let alone other issues that would occur (they use the disc id in 99% of cases).

I don't get your point.
As far as I can see, the wkf sees the fake header and skips it. So there should be no problem at all.

Ah, right you are! Never mind me, I didn't realize they slapped on a fake header and the real one was later on

I should stop browsing the web using text only and look at attached pictures more often :p

No problem, emu.

zenloc, an original wii disc header contains partition data, secret keys that encrypt it etc... the faked header just contains zeros (0x00) - its empty.
wii disc structure: http://wiibrew.org/wiki/Wii_Disc
gc disc structure: http://hitmen.c02.at/files/yagcd/yagcd/chap13.html

I think the wkf team was just lazy about the gc disc support and expands all (scrubbed or not) images to 1,36 gb.
So it is easier to read for the wkf and easier to implement in the wbfs manager.
As they didn't release the source code of their wbfs manager 4.0 modification, i will investigate the way it stores gamecube images to wbfs and then may be able to adjust the slots for scrubbed images.
And I am interested in the way wbfs manager estimates the size of a wii iso, will look for it and the 2 mb limit in the 3.0 source code, dont think they changed much of this, but who knows...

Wow, awesome findings. So basically at the moment any homebrew program under 2mb can be made into a .iso and hex edited to take up much less space right? Keep up the great work man

Really nice find
@infact (or some one else who probably knows this) where can I see how big a DOL of gcm is? I wasn't able to find it in the header... (used yagcd to do these things :p)

Infact, could you make us an .iso for WKF with Swiss r39?

Would be awesome!

~Hugo

Total noob here. I'm thinking about trying to make my own portable, and so far I'm planning on going with the WODE. Just want to check and ask if it'll be compatible with all gamecube models.

Hi Hugo_Peters, how's your portable going?

I attached the iso file, will make a short tutorial when I got some time later.

darksky72, so far the WODE is the best to go with. Only problem is the size.

infact wrote:darksky72, so far the WODE is the best to go with. Only problem is the size.

Alright, well I can probably live with that, I expect this whole thing to be quite bulky anyway, I've never done a portable before.

http://www.modchipcentral.com/store/wod ... anada.html
And this would be the correct product to purchase, right? It was the cheapest one I could find...

Just got 4 new cubes off ebay for 15$ + shipping. I ran them all thru the Wiikey test, I got 2x NTSC IPL v1.1 boards (DOL-CPU-11/DOL-CPU-30) and they work fine with the Wiikey. I got 1 board that is IPL v1.0 (DOL-CPU-10) that the Wiikey is once again incompatible with. Lastly I got a DOL-101 (with the built in regulator) with motherboard revision DOL-CPU-50. I can't tell what IPL its running though (I'm assuming either v1.1 or v1.2) because Swiss reports that its a Wii... lol. Wiikey Fusion is working with this board though

Ashen wrote:[...]Lastly I got a DOL-101 (with the built in regulator) with motherboard revision DOL-CPU-50. I can't tell what IPL its running though (I'm assuming either v1.1 or v1.2) because Swiss reports that its a Wii... lol. Wiikey Fusion is working with this board though

Hehe nice one

Well, swiss is reporting it as Wii because of the if-statement used to determine this:
So your model seems to report an other number than the default (ipl 1.0, 1.1...) gamecubes and swiss will show it as Wii.

they must have changed the mfpvr (cpu id) return value on the new boards

Any other way to identify the IPL version on that board then?

Ashen, I'll send you a modified version of Swiss tonight so I can get more info then I'll add it to the main source code.

Sounds good.

infact wrote:Hi Hugo_Peters, how's your portable going?

I attached the iso file, will make a short tutorial when I got some.

My portable is going great after the 4 messed up cubes. I'm currently using a DOL-CPU-01 board
made in Phils...

Thank you for the ISO! I'll test it out as soon as I have my FFC connector!

Just tested the iso. It works prefect and only take 2mb. Great work!

Emu_kidid. Is it possible to make swiss direct load the sd card. Also minus all the extra features that you won't use. I don't have any experience in coding. Is it difficult to try something like that?