BizHawk/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/Mapper233.cs

67 lines
1.3 KiB
C#

using BizHawk.Common;
using BizHawk.Common.NumberExtensions;
// http://wiki.nesdev.com/w/index.php/INES_Mapper_233
namespace BizHawk.Emulation.Cores.Nintendo.NES
{
internal sealed class Mapper233 : NesBoardBase
{
public int prg_page;
public bool prg_mode;
public override bool Configure(EDetectionOrigin origin)
{
switch (Cart.BoardType)
{
case "MAPPER233":
break;
default:
return false;
}
prg_mode = false;
return true;
}
public override void SyncState(Serializer ser)
{
ser.Sync(nameof(prg_page), ref prg_page);
ser.Sync(nameof(prg_mode), ref prg_mode);
base.SyncState(ser);
}
public override void WritePrg(int addr, byte value)
{
prg_page = value & 0x1F;
prg_mode = value.Bit(5);
int mirror = value >> 6;
switch (mirror)
{
case 0:
SetMirroring(0, 0, 0, 1);
break;
case 1:
SetMirrorType(EMirrorType.Vertical);
break;
case 2:
SetMirrorType(EMirrorType.Horizontal);
break;
case 3:
SetMirrorType(EMirrorType.OneScreenB);
break;
}
}
public override byte ReadPrg(int addr)
{
if (prg_mode == false)
{
return Rom[((prg_page >> 1) * 0x8000) + addr];
}
return Rom[(prg_page * 0x4000) + (addr & 0x3FFF)];
}
}
}