*.NDS Rom Info Scraping (C#)

Posted Aug 16, 2016 Updated Sep 20, 2023

By Richard Niemand

2 min read

I am starting a small ROM management project to help me keep my various ROM backups in order and make searching for a specific backup easier. I decided it would be a good idea to programmatically extract information from the ROM file and then scrape the www to get more detailed metadata about the ROM file in question.

Being new to all of this I spent some time on Google and found the following wiki page, that details the DSi Cartridge Header, thus allowing me to create a module for my ROM scraper that would be able to look for and extract all the basic information I need to begin scraping the web for more metadata.

From the wiki, I am interested mainly in the following bits of information:

Code	Length	Description
0x000	12	The title of the game
0x00C	4	The game code (used for lookups)
0x010	2	The code of the game developer
0x01E	1	ROM version
0x230	8	Title ID

With this information at hand I quickly put together the following sample project to check that I could pull the required information out of the ROM file.

  
class Program {
    static void Main(string[] args)
    {
        var source = @"E:\temp\test-rom.nds";
        var fs = new FileStream(source, FileMode.Open);
        var br = new BinaryReader(fs);

        Console.WriteLine("Game Name   : {0}", ReadBytes(br, 0x000, 12));
        Console.WriteLine("Game Code   : {0}", ReadBytes(br, 0x00C, 4));
        Console.WriteLine("Maker Code  : {0}", ReadBytes(br, 0x010, 2));
        Console.WriteLine("ROM Version : {0}", ReadBytes(br, 0x01E, 1));
        Console.WriteLine("Title ID    : {0}", ReadBytes(br, 0x230, 8));

        Console.WriteLine();
        Console.WriteLine("Done");
        Console.ReadLine();
    }

    private static string ReadBytes(BinaryReader br, int seek, int length)
    {
        byte[] test = new byte[length];
        br.BaseStream.Seek(seek, SeekOrigin.Begin);
        br.Read(test, 0, length);
        return Encoding.UTF8.GetString(test);
    }
}