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Bad Dudes in game text manipulation
Overview
In short, there is tons of text in video games, even old NES games. I for one want that text to say whatever I want. It is very possible to go in and change the character values that are being assigned to the values printed to the screen. The same NES emulator as before has a tool that actually displays the machine code of the game. Now since it is impossible to read machine code we first need something that will allow us to translate the machine code in to readable ascii.
Procedure
First it is necessary to create a key in order to be able to translate the machine language in to readable text. So the rom must be opened in the emulator and have the PPU Viewer open. The ppu viewer displays any sprites (pictures) on the screen in real time and shows a hex value for what each is. In this case when the text comes on we want to manipulate we go hover the cursor over the letters and it shows all of the hex values. So go through in a text file in a column format and write the hexvalue equal actual letter. after you have this the emulator wants a tbl extension on it..
The picture can be used as reference as it shows the exact work I'm mentioning. Now open the hex editor. Once again this shows all of the machine code and alows manipulation to take place. Go to the settings and set it to show this rom and then load your 'key' file, as you are the Key Master. Now search the text for any of the words of text. In this case go ahead and put the word 'kidnap' and ala kazam it takes you to a block of text you can manipulate. Just don't oferwrite the machine codes 'FF' spots. In this game they are line break(I overwrote them the first time and screwed up the text as it prints to the screen.) And BAM! You must now go save Karl Krauss from Cuban midgets.
Recap
Instead of manipulating memory this time the actual machine code of the game was manipulated. Manipulating the machine code is very useful for situations like this. However, this only really works when you have some kind of key like we were able to create with this. Sadly other than text there are no real usable keys that can be used. Most every part of these game manipulations have to take palce in different ways.
