127 lines
3.7 KiB
C#
127 lines
3.7 KiB
C#
namespace VirtualNes.Core
|
|
{
|
|
public class Mapper255 : Mapper
|
|
{
|
|
byte[] reg = new byte[4];
|
|
public Mapper255(NES parent) : base(parent)
|
|
{
|
|
}
|
|
|
|
public override void Reset()
|
|
{
|
|
MMU.SetPROM_32K_Bank(0);
|
|
MMU.SetVROM_8K_Bank(0);
|
|
MMU.SetVRAM_Mirror(MMU.VRAM_VMIRROR);
|
|
|
|
reg[0] = 0;
|
|
reg[1] = 0;
|
|
reg[2] = 0;
|
|
reg[3] = 0;
|
|
}
|
|
|
|
//BYTE Mapper255::ReadLow(WORD addr, BYTE data)
|
|
//{
|
|
// if (addr >= 0x5800)
|
|
// {
|
|
// return reg[addr & 0x0003] & 0x0F;
|
|
// }
|
|
// else
|
|
// {
|
|
// return addr >> 8;
|
|
// }
|
|
//}
|
|
public override byte ReadLow(ushort addr)
|
|
{
|
|
if (addr >= 0x5800)
|
|
{
|
|
return (byte)(reg[addr & 0x0003] & 0x0F);
|
|
}
|
|
else
|
|
{
|
|
return (byte)(addr >> 8);
|
|
}
|
|
}
|
|
|
|
|
|
public override void WriteLow(ushort addr, byte data)
|
|
{
|
|
if (addr >= 0x5800)
|
|
{
|
|
reg[addr & 0x0003] = (byte)(data & 0x0F);
|
|
}
|
|
}
|
|
public override void Write(ushort addr, byte data)
|
|
{
|
|
byte prg = (byte)((addr & 0x0F80) >> 7);
|
|
int chr = (byte)((addr & 0x003F));
|
|
int bank = (byte)((addr & 0x4000) >> 14);
|
|
|
|
if ((addr & 0x2000) != 0)
|
|
{
|
|
MMU.SetVRAM_Mirror(MMU.VRAM_HMIRROR);
|
|
}
|
|
else
|
|
{
|
|
MMU.SetVRAM_Mirror(MMU.VRAM_VMIRROR);
|
|
}
|
|
|
|
if ((addr & 0x1000) != 0)
|
|
{
|
|
if ((addr & 0x0040) != 0)
|
|
{
|
|
MMU.SetPROM_8K_Bank(4, 0x80 * bank + prg * 4 + 2);
|
|
MMU.SetPROM_8K_Bank(5, 0x80 * bank + prg * 4 + 3);
|
|
MMU.SetPROM_8K_Bank(6, 0x80 * bank + prg * 4 + 2);
|
|
MMU.SetPROM_8K_Bank(7, 0x80 * bank + prg * 4 + 3);
|
|
}
|
|
else
|
|
{
|
|
MMU.SetPROM_8K_Bank(4, 0x80 * bank + prg * 4 + 0);
|
|
MMU.SetPROM_8K_Bank(5, 0x80 * bank + prg * 4 + 1);
|
|
MMU.SetPROM_8K_Bank(6, 0x80 * bank + prg * 4 + 0);
|
|
MMU.SetPROM_8K_Bank(7, 0x80 * bank + prg * 4 + 1);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
MMU.SetPROM_8K_Bank(4, 0x80 * bank + prg * 4 + 0);
|
|
MMU.SetPROM_8K_Bank(5, 0x80 * bank + prg * 4 + 1);
|
|
MMU.SetPROM_8K_Bank(6, 0x80 * bank + prg * 4 + 2);
|
|
MMU.SetPROM_8K_Bank(7, 0x80 * bank + prg * 4 + 3);
|
|
}
|
|
|
|
MMU.SetVROM_1K_Bank(0, 0x200 * bank + chr * 8 + 0);
|
|
MMU.SetVROM_1K_Bank(1, 0x200 * bank + chr * 8 + 1);
|
|
MMU.SetVROM_1K_Bank(2, 0x200 * bank + chr * 8 + 2);
|
|
MMU.SetVROM_1K_Bank(3, 0x200 * bank + chr * 8 + 3);
|
|
MMU.SetVROM_1K_Bank(4, 0x200 * bank + chr * 8 + 4);
|
|
MMU.SetVROM_1K_Bank(5, 0x200 * bank + chr * 8 + 5);
|
|
MMU.SetVROM_1K_Bank(6, 0x200 * bank + chr * 8 + 6);
|
|
MMU.SetVROM_1K_Bank(7, 0x200 * bank + chr * 8 + 7);
|
|
}
|
|
|
|
// For state save
|
|
public override bool IsStateSave()
|
|
{
|
|
return true;
|
|
}
|
|
|
|
|
|
public override void SaveState(byte[] p)
|
|
{
|
|
p[0] = reg[0];
|
|
p[1] = reg[1];
|
|
p[2] = reg[2];
|
|
p[3] = reg[3];
|
|
}
|
|
|
|
public override void LoadState(byte[] p)
|
|
{
|
|
reg[0] = p[0];
|
|
reg[1] = p[1];
|
|
reg[2] = p[2];
|
|
reg[3] = p[3];
|
|
}
|
|
}
|
|
}
|