GameHacking.org Weekly Hacking Target (06-12-11) - The Legend of Zelda [NES]

[BeyondTheStatic]

Genie alters ROM instructions, in the address range $8000-$FFFF.
...
To find the address in ROM, put a write breakpoint on one of those addresses and restart the game. You'll notice it breaks right away. Go up a line, and you'll see the ROM address it's pulling from. That's the correct address for the genie code.

Ah, for some reason I wasn't getting it, thanks! That should help with other codes I've been struggling with (maybe SMB3 should be voted for soon; I've found some interesting addresses Data Crystal doesn't mention). I'll make sure to go over the GG guides again.

Infinite Bombs
KZNZVOVK
[B]NOTE: You must restart the game for it to take effect.[/B]

Another one, not sure about its usefulness:

Bombs Instantly Destroy All Hidden Caves in Rocks
ALEAVNAI
[B]NOTE: There will be minor graphical artifacts present in some places.[/B]

And this one is derived from Rick N. Bruns' "Rock Man" code:

Touch Any Wall to Produce Ghosts in Overworld
SZUXLZXX

[nuomega457]

The best I have found so far:

Bombs explode without delay
OZKYUPSP

I was trying to find another infinite bombs cheat (one that works [with the ROM I have, anyway]), and I've surely found the correct addresses, but the GG conversion will not work for some reason. Here they are:

0658=?? - infinite bombs (same as Phil The Hammer found)

7106=AD (freeze bomb count decrease)
-or-
7107=00 (set bomb decrease factor to zero)

Of course, what I was really looking for was a "bombs destroy all blocks" type of code, but my few weeks experience with this subject is not enough, I guess

Nice job BeyondTheStatic. Your GG code "Bombs explode without delay" works with the ROM I have. And it is just one code as where my version (in this thread) uses three par codes. I have been working on other bomb codes but haven't made much progress.

[rimsky82]

Is it common for the write addresses to be outside the bound of the game genie? I believe this is the first game I've seen to have it's write to ram address outside the bounds. Maybe it's just a small rom.

This is also my first time seeing it, but I guess that doesn't mean it's not common. Maybe they did it because of an inconsistency with the mapper or something, I dunno.

Invincible
APVLZLEY

Invincible (RAM)
7AF2 10

EDIT: I didn't notice that nolberto82 already hacked an invin code (7B3A 60). I don't know which is better or worse, or if they have the same effect.

[Abystus]

Is it common for the write addresses to be outside the bound of the game genie? I believe this is the first game I've seen to have it's write to ram address outside the bounds. Maybe it's just a small rom.

[rimsky82]

Infinite Health
SZEUYKVK
SKNUZLST
IOVUALST

I think this is pretty failsafe. I tested it to the end of the first dungeon. You can still collect hearts, and will never lose health. Be sure to use an emulator that respects the compare byte, or else things will get screwy, like not being able to enter any caves or dungeons.

Infinite Health (RAM)
7B78 15
7B82 C5
7B9F AD

Max/Infinite Hearts
066F FF
0670 FF

The hearts codes are already around, but they need to be together.

[rimsky82]

The addresses you've found are RAM addresses, therefore can not be used for the genie. Genie alters ROM instructions, in the address range $8000-$FFFF. There are many guides in the Library on making genie codes to get you going in the right direction.

EDIT:
Since I've now had a chance to hack this game myself, I noticed that it writes instructions to RAM when the game starts, so your 710X addresses are right, but are still in RAM. To find the address in ROM, put a write breakpoint on one of those addresses and restart the game. You'll notice it breaks right away. Go up a line, and you'll see the ROM address it's pulling from. That's the correct address for the genie code.

EDIT2:
Because of this, the genie codes that are made with this method will only work if they are enabled when the game starts. Using them with any savestates won't work unless the game was started with the codes when the savestate was made. This might be why you can't get them to work.

[BeyondTheStatic]

The best I have found so far:

Bombs explode without delay
OZKYUPSP

I was trying to find another infinite bombs cheat (one that works [with the ROM I have, anyway]), and I've surely found the correct addresses, but the GG conversion will not work for some reason. Here they are:

0658=?? - infinite bombs (same as Phil The Hammer found)

7106=AD (freeze bomb count decrease)
-or-
7107=00 (set bomb decrease factor to zero)

Of course, what I was really looking for was a "bombs destroy all blocks" type of code, but my few weeks experience with this subject is not enough, I guess

[nuomega457]

Nice job nuomega. Some useful addresses there.

Thanks Tony. If I find anything else, I will update my post so all the codes I find are in one place.

[Helder]

I used the PRG 0 version, the code changes a condition obviously but once I get to the dungeon walls there are no more breaks at this conditional so there must be another one a little bit further up on the ASM. I will look into it again,and the other 2 codes where much lower on the ASM and had some undesirable effects like moving up with out doing anything.

Edit : I just seen that thread, damn all that work for nothing lol oh well its good practice and I tried various conditionals to make it work the BNE seems to work best for this conditional. I wish the NES has a BRA command like the SNES.

[Abystus]

Walk Through Walls (Not Through Locked Doors)
EIONGPEP

Btw that code was already hacked here by Hybrid but only works outside dungeons. The version of the game affects this code, however it's the same address with the same modification resulting in the same GG code. In the post he was not able to obtain a code to actually walk through dungeon walls however. What version of the game are you playing on? Possibly the other WTW code you mentioned in your WTW thread will work for the other revision inside dungeons.

[Helder]

In the dungeons you can pass thru blocks water pretty much anything but doors can't be walked through and blocks can't be pushed either but using this code you can have all doors open.

All Doors/Walls Opened (Use only in Dungeons)
00EE:FF

[Abystus]

Can you still pass through a wall with a locked door or is it just the door you can't pass through?

[Helder]

Walk Through Walls (Not Through Locked Doors)
EIONGPEP

[Tony H]

Nice job nuomega. Some useful addresses there.

[nuomega457]

Here are a few that I found. I haven't fully tested them yet but they appear to be OK. Feel free to improve on them and make them better if you wish.

Enemy movement speed in overworld and dungeons:
03BD:??
03BE:??
03BF:??
03C0:??
03C1:??
03C2:??
Note: Using FF for all makes them ridiculously fast and insanely hard to hit. 50 makes them fast, 01 makes them move super slow. Only works on some types of enemies.

Enemy shooting speed
03C4:??
03C5:??
03C6:??
03C7:??
Note: Using FF for all makes them shoot ridiculously fast. 50 makes them fast, 01 makes them shoot super slow.

Link's sword makes no sound when you swing it.
0601:00
0603:00
0606:00
Note: Some music in the game might be messed up a little or not play at all.

Bombs explode immediately after you place them. (Tested only very early in the game)
0038:00
I would like to see instead of a bomb being placed, maybe an enemy, coin, heart that explodes like a bomb when you place it?

Weird color hues:
00FE:??
Using anything between 00 and FF makes to colors of the whole game have a different hue?

Santa Claus Link! (Plus, you can walk through enemies too!)
04F0:02

Lots of boulders falling off Death Mountain. Much more than the usual 3 boulders on the screen at any given time.
0515:00
Note: For no boulders, replace 00 with 03.