Failures making WTW codes (retro)...

[safaribans]

I'm a new member here, but I've been hacking codes for a long time.
I read over The Secrets of Professional GameShark(tm) Hacking, and tried my hand at making walk through walls codes...

I tried making a code for Castlevania II (NES), using all methods outlined in the faq, no dice.
Same goes for Earthbound (SNES).

If anyone has a tutorial or can provide their search method for any games mednafen or zsnes supports (both have very good cheat searches, and mednafen is consistent with that and all the systems it supports), that would be great.

I found WTW codes for Earthbound (somehow the code range is outside of 7****** I'm used to with zsnes, but it works...)

and a Link to the Past wtw code here

I'd really like to make my own, particularly for the NES final fantasies, Metroid, Zelda, and pretty much any 2d rpg...

I'm just wondering, is there some better method than the faq outlines, or something I've overlooked?

Thank you!

[Pugsy]

Some Walk on Wall codes are A LOT easier than others. For the harder ones you will definitely need to use a debugger though and ideally one with a decent TRACE to file command. I'm not sure about Mednafen or ZSNES as I've never used them. I use the MESS emulator which comes with the best debugger for any emulator and has a very good TRACE.

Just had a quick look at the NES game, not really my type of game and the only wall I could find to walk through was the one at the start so I don't know if this works properly as it may be passing a map boundary.

Castlevania II - Simon's Quest (U) [!]
AEVALULG Walk through Walls (don't add this code to the database - it's almost completely untested!)



Method with MESS and debugger for the above:

Enter the debugger
TRACE castle (this will make a text file which lists the instructions taken by the game one by one - it can get really BIG)
F12 (return to game)
Move about left and right a bit without hitting any walls
Enter the debugger
TRACE OFF
F12 (return to game)
Move to the wall and press up to it tightly
Enter the debugger
TRACE >>castle
F12 (return to game)
Now press left and as quick as you can press ` to enter the debugger (quicker the better as there will be less code to look through)
TRACE OFF
Now you have a TRACE file...open it up in a text editor and start working up from the bottom.

[safaribans]

Thank you Pugsy, yes MESS is great (I have the SDLMESS port) but I've never tried its debugger before. Mednafen has a debugger as well, but I'm so used to just looking for differing values, not sure what features it has...

I'll give things a go, and hopefully its not too much over my head...

I tried your code for Castlevania II (sorry it's not your type of game, people either love it or hate it) it works beautifully, so I'd vouch for it being added to the database here.

[Helder]

the code you mentioned for earthbound that is outside the 7******range is a ROM address very likely its a GG code decrypted, those cam only be made with a Trace and or Debugger. Look up Tony Hedstroms's guide on how to make GG codes with a Debugger and you will get the idea on how to make these GG codes.

[safaribans]

the code you mentioned for earthbound that is outside the 7******range is a ROM address very likely its a GG code decrypted, those cam only be made with a Trace and or Debugger. Look up Tony Hedstroms's guide on how to make GG codes with a Debugger and you will get the idea on how to make these GG codes.

Helder, is this the guide?
How to use a NES/6502 debugger to make Game Genie codes
http://gshi.org/?s=faqs&id=61

The faq is truncated...

[Tony H]

Here's the whole guide...

http://codehut.gshi.org/DebuggerGGcodes.txt

EDIT:
I recently did a slight update to it (fixed old/broken links and added GSHI as a place to find PAR codes instead of GSCentral).

[Helder]

thanks for the link Tony, I updated the info in the link provided by safaribans with your updated guide.

[Whipon]

That guide rocks. It was one of the first docs I read when I was a total newbie. It helped me greatly.

[Abystus]

WTW codes can be easy or difficult depending on the programmer's implementation. Some games will stop you at a position X or Y then attempt to force that position into your X or Y repeatedly, others will remove the ability to progress in a given direction if the above criteria is met, and then some have a set boundary of the amount of area within a given room your allowed to move.

You will most definitely need a debugger, also you will likely need a reference chart to the asm instruction set based on which system you are looking at. If you need a good reference chart for the snes check out The 6502 Instruction Set Decoded

Forced Position:

The Zelda code you posted above was my work, and used the first method of forcing your position based on your X or Y coordinate. Games that follow this routine are very easy to hack WTW codes for because you can usually set a break on write to find what address is writing the forced value and then implement a standard NOP on the found address. This basically gives the address forcing your position no operation stopping it from thwarting you any longer. Some games using this method will also have a secondary check which you can also NOP and should be found after the first address has been NOPed.

Removed Control (Given Direction):

The second type is where the game takes away the ability progress further in given direction. This method is a bit tougher to hack in my opinion. Actually my best guess on how to hack it would be to find the value for when you have the ability to move in given direction and when you don't (against a wall). You could try 0 and 1 or try less than,equal to, and greater than. There may be a simpler way to overcome this implementation but as far as I know its about finding the flag for movement in a direction.

Allocated "Area":

The third type is where the game sets a boundary of the "area" allocated for a given room and uses it as a boundary limitation for your character. To hack these you need to find the allocated area for each room. This can be found by moving from room to room and by using less than, equal to, greater than accordingly for each room. Once you have your allocated boundary number set the address value to 0. This will make the allocated "area" for each room 0 which will allow you to walk around freely since your considered outside the boundaries.

There may be other types but these are the 3 big ones I have encounted hacking the snes, nes, or pretty much any other 2d based game.

[Parasyte]

I'm "OK" with assembly hacking. At one time, I tried hacking a WTW for Super Mario Bros. just for giggles. As it turns out, that's the craziest game engine I've seen outside of Metroid Prime. I never completed that code.

Bonus points if you're able to get your codes working on a real NES (fits entirely within 3 GG codes). Actually, don't even bother if you cannot work within those limitations. Anything beyond that is a ROM hack. :P

[Pugsy]

I'm "OK" with assembly hacking. At one time, I tried hacking a WTW for Super Mario Bros. just for giggles. As it turns out, that's the craziest game engine I've seen outside of Metroid Prime. I never completed that code.

Bonus points if you're able to get your codes working on a real NES (fits entirely within 3 GG codes). Actually, don't even bother if you cannot work within those limitations. Anything beyond that is a ROM hack. :P

Bored, here's a quick WTW cheat for NES Super Mario Bros.


AVUSUIKZ - Walk Through Walls

[Hybrid]

nice code pugsy but can't get past level 1-1 with it on

[Pugsy]

oops, lack of testing...that's the problem with posting quick cheats.

I might take a proper ganders tomorrow.