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1. #SUPER STREET FIGHTER 2 TURBO MAME ROM HOW TO#
2. #SUPER STREET FIGHTER 2 TURBO MAME ROM ZIP FILE#
3. #SUPER STREET FIGHTER 2 TURBO MAME ROM SERIES#

We have to create a cheat file inside MAME’s “cheat” folder named the same as the ROM zip file but with xml extension, so for Super Street Fighter 2X (Japanese version of Super Turbo), the filename will be “ssf2xj.xml”. The MAME cheat system XML format is explained in the comments on the src/emu/cheat.c file inside MAME source code. Now let’s do the MAME cheat to be able to change this setting on the fly during gameplay, so we can adjust the difficulty while playing against the CPU. It appears that our guess was right, and we have found the place in memory where the Game Difficulty setting is stored. Type in the memory address of our previous finding and then switch the Game Difficulty in the System Configuration Menu to see if the memory value at 0xFF82D3 changes when we change the difficulty. To confirm our guess we’ll launch the Memory View window in MAME’s debugger, to do this just press CTRL+M and the Memory View window will appear. The first one is the probably the text displayed on the screen, while the second one is probably the position in memory where the difficulty value is stored, as we can guess it ranges from 0 (Easiest) to 7 (Hardest). We can see two values have changed, one at position 0x90C99D and the other at position 0xFF82D3. Now we will use the diff utility to see the difference between both files: So we’ll put the Game Difficulty setting to 1/Easiest and issue the following dump command: dump easiest.txt,0,0xffffff, then we’ll set the Game difficulty setting to 8/Hardest and repeat the command: dump hardest.txt,0,0xffffff. It expects a filename as first argument, the start address and the length of the memory portion we want to dump.

We can find the right syntax for the ‘ dump’ command using the debugger’s command ‘ help memory’. To do this we’ll use the debugger’s ‘ dump’ command, that dumps program memory as text. Now we need to discover what changes in the game’s memory when we change that setting. In the test menu, under “System Configuration” we can change the settings of the game, one of those settings is the Game Difficulty, ranging from 1/Easieast to 8/Hardest. To do this, we’ll press F5 (or type go in the debugger console) and we’ll press F2 (the “test switch” key) to access the game’s Test Menu. You can use the help command in the debugger to see the help.įor this first example we’ll create a cheat to change the game difficulty on the fly.

#SUPER STREET FIGHTER 2 TURBO MAME ROM SERIES#

This will (hopefully) be the first post of a series that will show more advanced use of the MAME debugger and dig deeper into reverse engineering Super Turbo.įirst we need to launch MAME using the -debug parameter, this will launch the MAME debugger.

#SUPER STREET FIGHTER 2 TURBO MAME ROM HOW TO#

In this post I will show how to debug the Super Street Fighter II Turbo ROM in MAME, to create a simple cheat.