BizHawk/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/Boards/Mapper029.cs

57 lines
1.2 KiB
C#

namespace BizHawk.Emulation.Cores.Nintendo.NES
{
// what is this?
internal sealed class Mapper029 : NesBoardBase
{
int prg;
int chr;
int prg_bank_mask_16k;
public override bool Configure(EDetectionOrigin origin)
{
switch (Cart.BoardType)
{
case "Mapper029":
case "UNIF_JERKFACE":
case "UNIF_RET-CUFROM":
break;
default:
return false;
}
SetMirrorType(EMirrorType.Vertical);
AssertChr(0);
AssertPrg(32, 64, 128, 256, 512, 1024);
Cart.WramSize = 8;
Cart.VramSize = 32;
prg_bank_mask_16k = Cart.PrgSize / 16 - 1;
return true;
}
public override void WritePrg(int addr, byte value)
{
chr = value & 3;
prg = (value >> 2) & prg_bank_mask_16k;
}
public override byte ReadPrg(int addr)
{
int bank = addr >= 0x4000 ? prg_bank_mask_16k : prg;
return Rom[bank << 14 | addr & 0x3fff];
}
public override byte ReadPpu(int addr)
{
if (addr < 0x2000)
return Vram[addr | chr << 13];
else
return base.ReadPpu(addr);
}
public override void WritePpu(int addr, byte value)
{
if (addr < 0x2000)
Vram[addr | chr << 13] = value;
else
base.WritePpu(addr, value);
}
}
}