NullDC Debugger

[lee4]

Yes.

I tried NOP'ing that value (Ammo ASM) in the GameShark and right as I fired the gun and the screen went blank. For me this system isn't as easy to hack as the others are.

I'll explain:

Start up gameshark on nullDC (there are two versions of the GS that are patched to work without the official Gameshark memory card)

I added this in for Code Veronica in the codelist:

Test code
010FF18C
00000009

And when the gun was fired the screen went black.

I tested the two codes in Chankast Cheater for nullDC

Sonic Adventure 2 (010523F6 00000009)
Resident Evil Code Veronica (010FF18C 00000009)

They do nothing, I still lose rings and bullets

As for GS are you use cracked RAW format version to use codes?

[47iscool]

I tested the two codes in Chankast Cheater for nullDC

Sonic Adventure 2 (010523F6 00000009)
Resident Evil Code Veronica (010FF18C 00000009)

They do nothing, I still lose rings and bullets

As for GS are you use cracked RAW format version to use codes?

Yes, the version that works without the CDX card and uses the VMU instead.

[asasega]

hello
you can use demul for asm dc hacking, it has a nice debugger with breakpoint on r,w,x
i made this for biohazard veronica gentei ban
8c0fc70c add -1,r4 opcode 74ff(original code)
change it to 7400 (add 0,r4) and you have inf bullets

i forgot to mention that you can change on the fly between dynarec and interpreter mode, which means that you can play at full speed until you reach a point where you want to hack and change to interpreter and so on

[Helder]

I haven't had much luck with it so could you post what version and plugins your using and make a short tutorial?

[asasega]

i used demul 0.49, it comes with two exe's, demul.exe and demuld.exe(the one with the debugger). I used the included plugins, except for the graphics, for which i used the DX graphics plugin from demul 0.48.
the debugger gets started automatically when you switch CPU mode to interpreter, and offcourse emulation will be much slower, but that's ok because you can switch on the fly between dynarec and interpreter mode, only drawback is that the debugger gets closed when you switch to dynarec.
the debugger is command driven, so no point and click
you get a window which is divided in four areas, you can switch between them with F1,F2,F3,F4
F1 is the registers window
F2 is the RAM
F3 is the code window(opcodes decoded to instructions)
F4 is the command window, where you input your commands. Here you can type help for built in commands

Example for Bio Veronica
1. Using cheat engine i found the slot address where i had my weapon(you can use artmoney if you want so you could gain directly DC ram values )
2. I switched CPU mode to interpreter in demul so that the debugger starts
3. In the debugger command windows accesed by F4, I typed db XXXXXXXX(address i found)(this command shows you a specific RAM address) to verify that is the correct address
4. Then i issue the command for breakpoint which is bp w XXXXXXXX (which means break when a write occurs to XXXXXXXX)
5. I fire a shot ingame and the emu stops and in the debugger window i looked at the code and notice that the sub is responsible for decreasing the ammo amount

don't forget to type help to learn the commands, you can scroll with pageup and pagedown, because depending off your desktop resolution not everything will fit on screen
F5 for stop/start game
F11 for stepping through the code after a breakpoint
you can type for example help bp, to learn about different breakpoints
bl will list your breakpoints
bc with this you can delete a breakpoint

[Helder]

Finally some useful info for the debugger, Thanks.

[47iscool]

Wonder if it can be used with CE. If so I may take another shot at DC hacking.

[luc-ita]

Sorry for "necrothread" or bump up this old thread but I really need help on Demul 0.4.9.
Spoiler Alert! Click to view...

When I set the command buttons then in-game nothing happens! For example in Toy story 2 I'm stuck at "Press start button".
Have you resolved or encountered this problem?

Above problem solved. But I've another question! How I can use/save/load save states?
I would like to do some ASM hacks for DC games.

Many thanks

EDIT: another question: I've unpacked an GDI game, and now I've all game files. My question is what's the executable?
For example Toy story 2 has a 1ST_READ.BIN file that is 8 megabyte of size. Is that the executable?

How I could dump ROM range from demul 0.4.9 and view in IDA PRO or any disassembler?