Try Sonic Adventure 2 for me

[MastaG]

Hi there,

I'm about to order the sd-adapter.
But it seems many dreamcast games do not work in sdiso mode.
One of my favorite games is Sonic Adventure 2.
It has very strong copy protection.
The dreamcast ripdb states that you need to patch 1st_read.bin with hack3 and then change two values:
CDE4 436A -> 0900 0900
1032 0D8B -> 0800 0D8B
This works, but it will not defeat the protection that causes graphics corruption in the last episode.

As far as I know, only Echelon managed to create a working rip.
So I got the Echelon one and applied their fix for the last episode.
Then I ripped 1st_read from their release.
They use audio/data and the data track starts at lba 11700.
11700 + 166 = 11866 which is 2E5A in hex and that would be 5A2E in scambled hex.
In order to boot it from sdiso this needs to be changed to lba 0.
0 + 166 = 166 which is A6 in hex and remains A6 because it's one byte.
I've opened their 1st_read.bin with hex workshop and it seems the "5A2E" occurs only once (before the cd001).
However the A600 occurs like 3 or 4 times.
That's why patching the Echelon 1st_read.bin wiith dahack/binhack causes it to fail.
They will patch each pair of "A600".
I've only altered the 5A2E -> A600 and removed the one protection scheme they have left 1032 0D8B -> 0800 0D8B.

It's now propperly patched for lba0 and it works in data/data mode.
I tested it with bootdreams and created a data/data cdi image and burned it with alcohol120%.
I couldn't test bin2boot because it doesn't work in wine(linux) nor windows7 x64.
However it whould work as long as you use the /nohack option.
Bootdreams doesn't patch katana games since its meant for homebrew anyways.

Anyways, I've uploaded the 1st_read.bin and ip.bin here: http://tabon.ath.cx/~mastag/sonic_adv_2_lba0.zip

Could someone please create a sdiso image and test it?
Just put the files from the zip-archive and the sonic2 folder in the data folder and create an iso.
DONT PATCH! It's already patched for lba0.

Thanks in advance