Playing around with reading gameboy roms, and maybe emulation
baileytownsend.dev
1mod cartridge_header;
2mod enums;
3
4use crate::cartridge_header::CartridgeHeader;
5use crate::enums::DestinationCode;
6use std::fs::File;
7use std::io::Read;
8
9// https://github.com/ISSOtm/gb-bootroms/blob/2dce25910043ce2ad1d1d3691436f2c7aabbda00/src/dmg.asm#L259-L269
10// Each tile is encoded using 2 (!) bytes
11// The tiles are represented below
12// XX.. .XX. XX.. .... .... .... .... .... .... ...X X... ....
13// XXX. .XX. XX.. .... ..XX .... .... .... .... ...X X... ....
14// XXX. .XX. .... .... .XXX X... .... .... .... ...X X... ....
15// XX.X .XX. XX.X X.XX ..XX ..XX XX.. XX.X X... XXXX X..X XXX.
16// XX.X .XX. XX.X XX.X X.XX .XX. .XX. XXX. XX.X X..X X.XX ..XX
17// XX.. XXX. XX.X X..X X.XX .XXX XXX. XX.. XX.X X..X X.XX ..XX
18// XX.. XXX. XX.X X..X X.XX .XX. .... XX.. XX.X X..X X.XX ..XX
19// XX.. .XX. XX.X X..X X.XX ..XX XXX. XX.. XX.. XXXX X..X XXX.
20const NINTENDO_LOGO: [u8; 48] = [
21 0x0CE, 0x0ED, 0x066, 0x066, 0x0CC, 0x00D, 0x000, 0x00B, 0x003, 0x073, 0x000, 0x083, 0x000,
22 0x00C, 0x000, 0x00D, 0x000, 0x008, 0x011, 0x01F, 0x088, 0x089, 0x000, 0x00E, 0x0DC, 0x0CC,
23 0x06E, 0x0E6, 0x0DD, 0x0DD, 0x0D9, 0x099, 0x0BB, 0x0BB, 0x067, 0x063, 0x06E, 0x00E, 0x0EC,
24 0x0CC, 0x0DD, 0x0DC, 0x099, 0x09F, 0x0BB, 0x0B9, 0x033, 0x03E,
25];
26
27// const ROM_NAME: &str = "OtherLegallyObtainedRom.gb";
28const ROM_NAME: &str = "LegallyObtainedRom.gb";
29
30fn main() -> std::io::Result<()> {
31 let mut rom_file = File::open(ROM_NAME)?;
32 let mut rom_buffer: Vec<u8> = Vec::new();
33 rom_file.read_to_end(&mut rom_buffer)?;
34 let cart_header = match CartridgeHeader::parse(&*rom_buffer) {
35 Ok(header) => header,
36 Err(_err) => {
37 return Err(std::io::Error::new(
38 std::io::ErrorKind::Other,
39 "Rom failed to parse",
40 ));
41 }
42 };
43
44 let title: String = String::from_iter(cart_header.title);
45 println!("Title: {}", title);
46 let manufacturer_code = String::from_iter(cart_header.manufacturer_code);
47 println!("Manufacturer Code: {}", manufacturer_code);
48
49 match cart_header.old_licensee_code {
50 Some(code) => println!("Uses Old Licensee Code: {:#X}", code),
51 None => println!(
52 "Uses New Licensee Code: {}",
53 String::from_iter(cart_header.license_code)
54 ),
55 }
56
57 println!("CGB Flag: {:?}", cart_header.cgb_flag);
58 println!("Supports SGB: {:?}", cart_header.support_gb);
59 println!("Cartridge Type: {:?}", cart_header.cart_type);
60 println!("ROM Size: {:?}", cart_header.rom_size);
61 println!("RAM Size: {:?}", cart_header.ram_size);
62 match cart_header.destination_code {
63 DestinationCode::Japan => println!("Destination Code: Japan"),
64 DestinationCode::NotJapan => println!("Destination Code: Not Japan"),
65 }
66 println!("Version: {:?}", cart_header.version);
67 println!("Header Checksum: {:#X}", cart_header.header_checksum);
68 println!("Global Checksum: {:#X}", cart_header.global_checksum);
69
70 Ok(())
71}