Zophar's Message Domain

Go Back   Zophar's Message Domain > Emulation Talk > Rom Hack

Reply
 
Thread Tools Display Modes
Old 08-17-2010, 02:44 AM   #1
bilscorbe
Junior Member
 
Join Date: Aug 2010
Posts: 4
Default want to start hobby hacking

Ok so I want to get into a little bit of hacking, mainly for creating ips cheat patches, cause I'm too lazy to play a game all the way through while being frustrated. Any way, I want to hex edit the values in oracle of ages, that pertain to my energy bar, but I don't even know how to find the right values, and I'm not even sure I have a clue what I am doing in the first place. I'm just wondering if anyone has a direction they could point me in or some pointers, or even a preferred hex editor that I should look into. Any help would be appreciated.
Bill
bilscorbe is offline   Reply With Quote
Old 08-17-2010, 04:27 AM   #2
Reaper man
Member
 
Reaper man's Avatar
 
Join Date: Apr 2002
Location: Austin, TX
Posts: 5,409
Default

Sure, just translate this into binary decimal for me (little endian, signed) 0x3175B9FD
__________________
Reaper man is offline   Reply With Quote
Old 08-17-2010, 04:56 AM   #3
InVerse
Senior Member
 
Join Date: Jul 2002
Location: Midwest, U.S.
Posts: 1,489
Default

First off, if you're just wanting to cheat, it would be simpler to hack save states or use cheat codes. You can find several Gameshark codes here. If you want to make those codes permanent within the ROM, Google for convert Gameshark codes to ROM addresses and you'll find tutorials on how to do so. (I haven't read any of them, so I can't vouch for which ones are the best but I did the search and found a few to choose from.)

If you want to go about it in another way, what you'll need to do is become familiar with debuggers. There's a sticky post on this forum in which Reaper man explains the basics of this. (His tutorial is for PSX but the basic information is the same regardless of system.)

You can do this with a hex editor but it could very well take you months rather than the minutes it could take with a debugger. When you do need a hex editor, Windhex is your best bet for ROM hacking specific tasks. For basic hex editing, I prefer Hex Workshop, but it's a commercial editor so you'll probably prefer to use something free. I've heard good things about HxD but haven't actually used it myself, so I can't comment.


Quote:
Originally Posted by Reaper man View Post
Sure, just translate this into binary for me (little endian, signed) 0x3175B9FD
Uh..... I fail to see the relevancy? That's not even something I could do without researching it first (converting to binary is easy enough but I'd have to look up which endian direction is which and what signed means) but I don't see the point. Then again, I have a degree in computer programming, have been ROM hacking for a dozen or so years and think math is stupid.
InVerse is offline   Reply With Quote
Old 08-17-2010, 03:56 PM   #4
Reaper man
Member
 
Reaper man's Avatar
 
Join Date: Apr 2002
Location: Austin, TX
Posts: 5,409
Default

Quote:
Originally Posted by The Drunken Hacker View Post
Uh..... I fail to see the relevancy? That's not even something I could do without researching it first (converting to binary is easy enough but I'd have to look up which endian direction is which and what signed means) but I don't see the point. Then again, I have a degree in computer programming, have been ROM hacking for a dozen or so years and think math is stupid.
Just a simple test to see if he knew how to read hex values.

EDIT: And I just found a really dumb typo on my part...
__________________
Reaper man is offline   Reply With Quote
Old 08-18-2010, 01:05 AM   #5
bilscorbe
Junior Member
 
Join Date: Aug 2010
Posts: 4
Default

No seriously I appreciate the help guys, it is something I want to play around with in spare time, when my coursework is caught up anyway lol! I can deal with different base numbers, and I enjoy math so that doesn't really scare me much, but I will take a read through of that sticky. I'll be working on this for a while I'd imagine, if I run into trouble, I hope you don't mind throwing me a bone, if it's not too much to ask, hopefully? Yo Reaper Man:829798909. Gotta be honest, I didn't work it out by hand, I used the windows calculator. Thanks again guys, I'll talk to you laters!

Bill
bilscorbe is offline   Reply With Quote
Old 08-18-2010, 03:52 AM   #6
Reaper man
Member
 
Reaper man's Avatar
 
Join Date: Apr 2002
Location: Austin, TX
Posts: 5,409
Default

Quote:
Originally Posted by bilscorbe View Post
Yo Reaper Man:829798909. Gotta be honest, I didn't work it out by hand, I used the windows calculator.
Incorrect. I'll give you a hint. It's supposed to be a negative number.
__________________
Reaper man is offline   Reply With Quote
Old 08-18-2010, 04:11 PM   #7
pipes
Senior Member
 
pipes's Avatar
 
Join Date: May 2003
Posts: 1,883
Default

can I guess -1174589067?
__________________
The pipes never clangor.
pipes is offline   Reply With Quote
Old 08-18-2010, 05:15 PM   #8
Reaper man
Member
 
Reaper man's Avatar
 
Join Date: Apr 2002
Location: Austin, TX
Posts: 5,409
Default

Quote:
Originally Posted by pipes View Post
can I guess -1174589067?
My result was -38177487
__________________
Reaper man is offline   Reply With Quote
Old 08-19-2010, 12:47 AM   #9
bilscorbe
Junior Member
 
Join Date: Aug 2010
Posts: 4
Default

lol, guess I got more work to do, ya? Hoping to do some reading of your sticky this weekend when I get a chance.
bilscorbe is offline   Reply With Quote
Old 08-19-2010, 03:49 AM   #10
Reaper man
Member
 
Reaper man's Avatar
 
Join Date: Apr 2002
Location: Austin, TX
Posts: 5,409
Default

Quote:
Originally Posted by bilscorbe View Post
lol, guess I got more work to do, ya? Hoping to do some reading of your sticky this weekend when I get a chance.
before you even begin to look at my guide I seriously suggest looking up hexdecimal, endianess, signed/unsigned values, and bitwise operations.
__________________
Reaper man is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 09:26 PM.

Contact Us - Zophar's Domain - Archive - Top

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.