public Cartridge(string romFile)
{
var rom = File.ReadAllBytes(romFile);
this.ROM = new StandardROM(rom);//this will be discarded if the header says a different type.
this.info = ReadInfo();
this.info.FileName = romFile;
switch (this.info.Type)
{
case CartridgeType.ROM_ONLY:
this.ROM = new StandardROM(rom);
break;
case var t when(byte) t <= 0x03:
this.ROM = new MBC1(rom, this.info);
break;
case var t when(byte) t == 0x05 || (byte)t == 0x06:
this.ROM = new MBC2(rom, this.info);
break;
case var t when(byte) t >= 0xf && (byte)t <= 0x13:
this.ROM = new MBC3(rom, this.info);
break;
case var t when(byte) t >= 0x19 && (byte)t <= 0x1e:
this.ROM = new MBC5(rom, this.info);
break;
case CartridgeType.HuC1_RAM_BATTERY:
this.ROM = new Huc1(rom, this.info);
break;
default:
throw new NotImplementedException($"Rom type {this.info.Type} has not been implemented in this emulator");
}
}
private RomInfo ReadInfo()
{
RomInfo result = new RomInfo();
result.Name = Encoding.UTF8.GetString(this.ReadBytes(AddressHelper.ROM_TITLE, GB_TITLE_LENGTH)).Trim('\0');
//Read the cgb flag.
if (result.Name.Length == 11)
{
result.CGB = (CGBcompat)this.ReadByte(AddressHelper.CGB_FLAG);
}
else
{
result.CGB = CGBcompat.GB;
}
result.Size = (RomSize)this.ReadByte(AddressHelper.ROM_SIZE);
result.Type = (CartridgeType)this.ReadByte(AddressHelper.CART_TYPE);
result.Destination = (Destination)this.ReadByte(AddressHelper.DESTINATION);
result.ExternalRam = (ExRam)this.ReadByte(AddressHelper.RAM_SIZE);
int ramSize;
switch (result.ExternalRam)
{
case ExRam.k2:
ramSize = 1 << 12;
break;
case ExRam.k8:
ramSize = 1 << 13;
break;
case ExRam.k32:
ramSize = 1 << 15;
break;
case ExRam.k128:
ramSize = 1 << 17;
break;
case ExRam.k64:
ramSize = 1 << 16;
break;
default:
ramSize = 0;
break;
}
result.ExRamSize = ramSize;
switch (result.Size)
{
case RomSize.k32:
result.RomBytes = 2 << 15;
break;
case RomSize.k64:
result.RomBytes = 2 << 16;
break;
case RomSize.k128:
result.RomBytes = 2 << 17;
break;
case RomSize.k256:
result.RomBytes = 2 << 18;
break;
case RomSize.k512:
result.RomBytes = 2 << 19;
break;
case RomSize.m1:
result.RomBytes = 2 << 20;
break;
case RomSize.m2:
result.RomBytes = 2 << 21;
break;
case RomSize.m4:
result.RomBytes = 2 << 22;
break;
case RomSize.m8:
result.RomBytes = 2 << 23;
break;
default:
throw new NotImplementedException();
}
return(result);
}
