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Old April 2nd, 2007   #76 (permalink)
Link0x
Registered User
 
Join Date: Apr 2007
Location: near Frankfurt, Germany
Posts: 8
Wink

So far, I'm impressed...

now let me add another game to that list:

Sonic Shuffle

Computer specs:
AMD Sempron 2600+ (soon to be replaced)
1024 MB DDR Ram
GeForce 6600 GT
Windows XP

nullDC configuration:
Several tested:
-CP pass disabled
-Dynarec disabled
-Chankast graphics plug-in

Status with original (Echelon) ISO: Only until main menu
That's actually better than all other DC emulators so far, those even crashed before the main menu. In nullDC no matter what options are selected in the main menu once you leave it the screen goes black, the music accelerates to normal speed and over! Additionally the menu initialization shows a minor graphics glitch! Intro works! I have added a (probably useless) screenshot of the console output after it crashes

Add: Status with hex-edited ISO: Works
Open the ISO in a hex-editor: search for the following hex string:
20 90 0E A0 09 00 01 7E
Change the first instance of the finding to:
20 90 09 00 09 00 01 7E
as you see, only 2 bytes are changed.. but those 2 bytes make the ISO compatible (seems like nearly 100%) - there will be errors in the console but ignore them, it will work!
note: this edit was done on the MDF file.. if you have CDI version I am not sure whether this works but I guess so!
note 2: this edit makes the rom incompatible to Chankast (will show an error and abort) - demul will run it but still won't reach the menu

Status In debugger: Works
Stop the game when it seems to have crashed.. step through every instruction until you reach a "bra" command.. skip that command!
The command is the following: 8C029802 bra 0x8C029822 ; I guess it would be safe to overwrite that command with a "nop" command, just I haven't seen a function for doing so!
This command and an additional "rts" command puts the game in an endless loop

Bugs: major graphical issues in split-screen minigames!
Attached Images
File Type: jpg ss03.jpg (69.9 KB, 32 views)
File Type: jpg ss04.jpg (121.2 KB, 8 views)
File Type: jpg ss05.jpg (96.7 KB, 10 views)
File Type: jpg ss07.jpg (95.1 KB, 8 views)
File Type: jpg ss08.jpg (123.9 KB, 32 views)

Last edited by Link0x; April 2nd, 2007 at 18:58.. Reason: Hex-Editing trick added
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