All the other banks are written to exist at either 0xA000-0xBFFF or 0xC000-0xDFFF. 3, banks 30 and 31 are always present at addresses 0x8000-0x9FFF and 0圎000-0xFFFF, respectively. The NES memory map is shown in the following figure. Super mario bros 3 rom code#This extra hardware allowed the process of banking to occur, where running code could write to special registers on the cartridge to swap in and out specific banks of the PRG code when it needed them. In order to fit the entire game’s code in 32 KB, the MMC3 mapper hardware was used within the cartridge. RAM and other peripherals are mapped at lower memory addresses. However, the 6502 processor only supports 16-bit addressing and was only designed to address 32 KB of PRG ROM in the 32 KB of address space from 0x8000 through 0xFFFF. The cartridge contents are broken up into the PRG ROM (program memory) consisting of 32 banks of 8,192-byte blocks of 6502 code and the CHR ROM (character memory) consisting of 128 blocks of 1,024-byte graphics data. There is a 16-byte INES header followed by the actual cartridge contents. Other than that, there’s some minor differences in the location of some routines in bank 31.Ĭaptain Southbird’s disassembly assembles byte-for-byte into the PRG1 version of the ROM, and therefore the symbols and their addresses in the loader are matched to that ROM. US (Revision 0) US (Revision 1) Grass Land Grass Land Desert Hill Desert Land Ocean Side Water Land Big Island Giant Land The Sky Sky Land Iced Land Ice Land Pipe Maze Pipe Land Castle of Koopa Dark Land The different names are shown in the table below. The only major visual difference between the two are the names of the Worlds as shown during the end credits after beating the game. Their respective ROM files are suffixed (U) (PRG0) and (U) (PRG1). There were two versions of the Super Mario Bros. 3 NES ROM Ghidra Loader source can be found on my GitHub at Super Mario Bros. I helped develop the Early Hammer Manipulation and had a part in developing many of the new tech features in MitchFlowerPower’s ROM hack, Mini Kaizo Bros. 3 for the past year in order to find glitches or exploit logic in the game so as to support the top tier runners and their attempts to lower the world record times. 3 speedrunning community, I have been doing reverse engineering and understanding the mechanics behind much of Super Mario Bros. This loader currently does not allow analysis flow into or out of banks that are swapped in/out during runtime (all banks but two), as described in the post below.įor those unfamiliar with the Super Mario Bros. I’ve completed a Ghidra loader that correctly maps in all the ROM’s program banks at their respective addresses along with all of the symbols from the complete disassembly located on GitHub. Super mario bros 3 rom full#3 NES ROM with all the symbols from Captain Southbird’s full disassembly. A loader specifically for loading the PRG1 version of the Super Mario Bros.
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