BizHawk/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper201.cs

100 lines
2.0 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace BizHawk.Emulation.Consoles.Nintendo
{
class Mapper201 : NES.NESBoardBase
{
/*
Here are Disch's original notes:
========================
= Mapper 201 =
========================
Example Games:
--------------------------
8-in-1
21-in-1 (2006-CA) (Unl)
Registers:
---------------------------
$8000-FFFF: A~[.... .... RRRR RRRR]
R = PRG/CHR Reg
CHR Setup:
---------------------------
$0000 $0400 $0800 $0C00 $1000 $1400 $1800 $1C00
+---------------------------------------------------------------+
| $8000 |
+---------------------------------------------------------------+
PRG Setup:
---------------------------
$8000 $A000 $C000 $E000
+-------------------------------+
| $8000 |
+-------------------------------+
*/
public int reg;
public int prg_bank_mask_32k;
public int chr_bank_mask_8k;
public override bool Configure(NES.EDetectionOrigin origin)
{
switch (Cart.board_type)
{
case "MAPPER201":
break;
default:
return false;
}
SetMirrorType(EMirrorType.Vertical);
prg_bank_mask_32k = Cart.prg_size / 32 - 1;
chr_bank_mask_8k = Cart.chr_size / 8 - 1;
return true;
}
public override void SyncState(Serializer ser)
{
ser.Sync("reg", ref reg);
base.SyncState(ser);
}
public override void WritePRG(int addr, byte value)
{
if ((addr & 0x08) > 0)
{
reg = addr & 0x03;
}
else
{
reg = 0;
}
}
public override byte ReadPRG(int addr)
{
return ROM[((reg & prg_bank_mask_32k) * 0x8000) + addr];
}
public override byte ReadPPU(int addr)
{
if (addr < 0x2000)
{
return VROM[((reg & chr_bank_mask_8k) * 0x2000) + addr];
}
return base.ReadPPU(addr);
}
}
}