US Version of N64 64DD has been found !

The IPLs are unique, and the disk they dumped contains something we already dumped though. And anyway we don't need to dump it to access it.

 

The dissapointing thing is knowing that alot of these blue disks could have gone blank by now, even if you just have them laying around. That's way worst than worrying about bitrot.

 

That's why this video exists, to get the word known

 

Very happy that SOMETHING was found. Thanks!

 

Hi LuigiBlood,
I heard about this amazing find when Metal Jesus released the first video....

I work in Electronics Test Development, so as for myself, I'm looking at this from more of a hardware perspective;
I wonder what the real differences are between the 64DD USA system that Metal Jesus has found,
compared to a Japanese version?.... As far as the internal hardware is concerned?

I'm really curious to know if there would be any way of transferring the Firmware Dump for the USA Version that was just acquired,
and getting it to run on a Japanese Dev. system?

Or are there specific components between the two that would prevent this?

Are there any photos of the 64DD JPN system internals?
or specific documentation on the internal circuitry and hardware?

I'd be very curious to know if something like this could be implemented.
Any thoughts on this idea?

Kind Regards,
Gerry O'Brien

 

I suspect the internals are identical to the japanese one with one exception: CIC chip is not the same. I want to know the ID of it.

There's probably a way of transferring the firmware dump but honestly I don't see a point when USA disks are not being found.
There's not much documentation about the hardware, at best you can find pictures (I forgot the links, sorry.)
I believe the disk region locking is done by the IPL itself.

 

The USA drive also reports different flags in the device attrib register at A5000540. It should be in the pattern 04_3____, not the 00_3____ reported by Japanese drives or 00_1____ used in very early ones. A reg dump would have been useful (and taken <5 seconds) to verify this and any other peculiarities.

Disk region is set by the IPL. In the USA IPL this will be at 802611D4/802611DC (0x21D4/0x21DC). The test works in two ways:
1) When booting a disk, an equality test is run at 80273BEC. If not equal expect an infinite loop.
2) This value is split into bytes and copied to 80000010, 80000090, 80000110, and 80000190. After reboot (and assuming official libs are used), the disk will read these values back and reconfirm against the disk's region code.

 

The interesting thing is that on emulator it's just 00030000 and USA IPL doesn't complain.

 

For reference the code is at: 8026179C (0x279C).