Register - Login
Views: 99794360
 Main - Memberlist - Active users - Calendar - Wiki - IRC Chat - Online users
Ranks - Rules/FAQ - Stats - Latest Posts - Color Chart - Smilies 		05-03-22 05:13:31 AM
Jul - General Game/ROM Hacking - I got the rom and tools, now what? New poll - New thread - New reply
Next newer thread | Next older thread
servbot128

Level: 12


Posts: 1/24
EXP: 6826
For next: 1095

Since: 02-07-13


Since last post: 9.2 years
Last activity: 9.0 years
Posted on 02-07-13 05:31:53 PM Link | Quote
Hi I'm new and stuff but that's not the point of this thread, I want to make a hack of yellow but I don't know how, I have a working emu, rom and tools to adjust everything but I do I hack it? (I have 0 experience with hacking$

____________________
We can make it hotter with your hell.
GuyPerfect
Catgirl
Level: 68


Posts: 811/1096
EXP: 2665653
For next: 63147

Since: 07-23-07


Since last post: 1.7 years
Last activity: 219 days
Posted on 02-10-13 06:22:10 PM Link | Quote
By "yellow" I assume you're referring to Pokémon Special Pikachu Edition. And from that, I can refer you to the Pan Docs, which has everything you need to know about hacking Game Boy games.

For hacking, you'll need an emulator with a debugger of sorts, such as NO$GMB or, as I would prefer, its hacking-centric counterpart BGB. I've had a lot of success with the disassembler and breakpoint features of BGB, so that would be the place to start.

Familiarize yourself with the specifics of the CPU in the document, followed by the system memory map. Armed with that knowledge, you'll be able to look at the disassembly while the game is running and know exactly what it's doing. That's the bread and butter of good hacking.
GuyPerfect
Catgirl
Level: 68


Posts: 812/1096
EXP: 2665653
For next: 63147

Since: 07-23-07


Since last post: 1.7 years
Last activity: 219 days
Posted on 02-10-13 06:31:33 PM Link | Quote
As long as I'm on the topic, I have some useful links for hacking various systems, most of which from the Nocash guy:

• NES - Everynes by Martin Korth
• SNES - Fullsness by Martin Korth
• GB/SGB/GBC - The Pan Docs by Martin Korth
• GBA/NDS - GBATek by Martin Korth
• VB - VB Sacred Tech Scroll by yours truly
Xenesis

Roy Koopa
Actually a Doctor
Level: 101


Posts: 2008/2732
EXP: 10486589
For next: 231086

Since: 07-28-07

Pronouns: She/Her
From: Orange Star's Retirement Villa

Since last post: 9 days
Last activity: 19 hours
Posted on 02-10-13 10:44:43 PM Link | Quote
I'll be quite honest GuyPerfect, that's like giving someone an engineering manual when they're just learning how Legos work.

If someone threw no$ docs at me when I was just getting started, I probably would have run screaming - it's an amazing resource, but it is a bit indecipherable if you don't even know the basics of binary or any programming/hacking jargon.

servbot:

A big question is how much knowledge you have to begin with. Do you have any programming knowledge/skills? Do you know and understand hexidecimal notation? More to the point, what exactly do you want to do with your hack, because doing different things requires different skillsets.

People are happy to help you learn things, we've just got to know what your knowledge level of various things is.
neotransotaku
Member
wonders why OSX does not come with their version of MSPaint?
Level: 53


Posts: 600/603
EXP: 1084687
For next: 72432

Since: 08-24-07

From: The Landmark @ One Market

Since last post: 2.6 years
Last activity: 41 days
Posted on 02-11-13 01:23:24 AM (last edited by neotransotaku at 02-11-13 01:28:20 AM) Link | Quote
When it comes to GB/GBC hacking, this is where those docs are gibberish to me. Not to say that I can't understand them, but rather how do I even begin to use that information to attempt to find what I want? For instance, I want to change the title screen for a Pokemon game. I can load up BGB in debug mode, enable the VRAM viewer, and pause the game prior to the intro screen for showing up. I know at some point, the pokemon code between 0:0000-0:3fff (or maybe even x:4000-x:7ffff) will load up from the ROM the intro screen and put it between 0:8000-0:9000. How can I find that code (or even breakpoint it)?

To change text, one needs to do relative searching assuming the text is not completely graphics based or compressed. If it is compressed, you are up the creek with that approach.

To change graphics, there are tools that will allow you to explore a ROM to find the graphics. This only works as long as the graphics aren't compressed and you are viewing them in the right bbp so that it won't look convoluted.

I don't mean to hijack servbot's thread, but I could use guidance on the first item, which will probably break open the second and third items. For servbot, he needs to let us know what he wants to do so that we all can guide him in the right direction, and help him break into it so that he is welcome to this community. Otherwise, he'll be intimidated by the community.
xdaniel
980
Level: 64


Posts: 414/982
EXP: 2153582
For next: 60515

Since: 12-04-08

Pronouns: he/they
From: Germany

Since last post: 25 days
Last activity: 39 min.
Posted on 02-11-13 01:42:02 AM (last edited by xdaniel at 02-11-13 01:53:15 AM) Link | Quote


>>ESTABLISHING LINK...DONE.    >>FETCHING POST DATA...DONE.    >>EXECUTING POSTDISP.BIN...


Originally posted by neotransotaku
For instance, I want to change the title screen for a Pokemon game. I can load up BGB in debug mode, enable the VRAM viewer, and pause the game prior to the intro screen for showing up. I know at some point, the pokemon code between 0:0000-0:3fff (or maybe even x:4000-x:7ffff) will load up from the ROM the intro screen and put it between 0:8000-0:9000. How can I find that code (or even breakpoint it)?

Setting a write breakpoint on the address in VRAM where the first tile is written to? Not sure if BGB can do that, but IIRC No$GMB can. I do seem to remember seeing some GB game's tiles being loaded into VRAM pixel per pixel while stepping through the code, at least...

Edit: Yep, tried it with Tetris in No$GMB. Setting a breakpoint as "(8000)!" will create a breakpoint on write to memory location 8000, beginning of VRAM. And while it's not pixel by pixel, I can see each tile of the game's font get loaded in (almost) line by line if I step through the code with F3.


____________________
cu xdaniel - Follower of the Church of Madoka


"What color is your BLOOD?!?"
servbot128

Level: 12


Posts: 12/24
EXP: 6826
For next: 1095

Since: 02-07-13


Since last post: 9.2 years
Last activity: 9.0 years
Posted on 02-11-13 03:59:28 AM Link | Quote
Originally posted by Xenesis
I'll be quite honest GuyPerfect, that's like giving someone an engineering manual when they're just learning how Legos work.

If someone threw no$ docs at me when I was just getting started, I probably would have run screaming - it's an amazing resource, but it is a bit indecipherable if you don't even know the basics of binary or any programming/hacking jargon.

servbot:

A big question is how much knowledge you have to begin with. Do you have any programming knowledge/skills? Do you know and understand hexadecimal notation? More to the point, what exactly do you want to do with your hack, because doing different things requires different skillsets.

People are happy to help you learn things, we've just got to know what your knowledge level of various things is.

Hacking its self I'm not familiar with but I have a general understanding of how the programs work I just need to know how to use them. (I'm using Kigb)

____________________
We can make it hotter with your hell.
Next newer thread | Next older thread
Jul - General Game/ROM Hacking - I got the rom and tools, now what? New poll - New thread - New reply


Rusted Logic

Acmlmboard - commit 47be4dc [2021-08-23]
©2000-2022 Acmlm, Xkeeper, Kaito Sinclaire, et al.

31 database queries, 2 query cache hits.
Query execution time: 0.100469 seconds
Script execution time: 0.012648 seconds
Total render time: 0.113117 seconds