96 lines
2.0 KiB
C#
96 lines
2.0 KiB
C#
using System;
|
|
using System.Collections.Generic;
|
|
using System.Linq;
|
|
using System.Text;
|
|
|
|
namespace BizHawk.Emulation.Consoles.Nintendo
|
|
{
|
|
class Mapper203 : NES.NESBoardBase
|
|
{
|
|
/*
|
|
Here are Disch's original notes:
|
|
========================
|
|
= Mapper 203 =
|
|
========================
|
|
|
|
Example Games:
|
|
--------------------------
|
|
35-in-1
|
|
|
|
|
|
Registers:
|
|
---------------------------
|
|
|
|
|
|
$8000-FFFF: [PPPP PPCC]
|
|
P = PRG Reg
|
|
C = CHR Reg
|
|
|
|
|
|
CHR Setup:
|
|
---------------------------
|
|
|
|
$0000 $0400 $0800 $0C00 $1000 $1400 $1800 $1C00
|
|
+---------------------------------------------------------------+
|
|
| $8000 |
|
|
+---------------------------------------------------------------+
|
|
|
|
|
|
PRG Setup:
|
|
---------------------------
|
|
|
|
$8000 $A000 $C000 $E000
|
|
+---------------+---------------+
|
|
| $8000 | $8000 |
|
|
+---------------+---------------+
|
|
*/
|
|
|
|
int prg_reg_16k, chr_reg_8k;
|
|
int prg_bank_mask_16k;
|
|
int chr_bank_mask_8k;
|
|
|
|
public override bool Configure(NES.EDetectionOrigin origin)
|
|
{
|
|
switch (Cart.board_type)
|
|
{
|
|
case "MAPPER203":
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
prg_bank_mask_16k = Cart.prg_size / 16 - 1;
|
|
chr_bank_mask_8k = Cart.chr_size / 8 - 1;
|
|
|
|
return true;
|
|
}
|
|
|
|
public override void SyncState(Serializer ser)
|
|
{
|
|
ser.Sync("prg_reg_16k", ref prg_reg_16k);
|
|
ser.Sync("chr_reg_8k", ref chr_reg_8k);
|
|
base.SyncState(ser);
|
|
}
|
|
|
|
public override void WritePRG(int addr, byte value)
|
|
{
|
|
prg_reg_16k = (value >> 2) & prg_bank_mask_16k;
|
|
chr_reg_8k = (value & 0x03) & chr_bank_mask_8k;
|
|
}
|
|
|
|
public override byte ReadPRG(int addr)
|
|
{
|
|
return ROM[(prg_reg_16k * 0x4000) + (addr & 0x3FFF)];
|
|
}
|
|
|
|
public override byte ReadPPU(int addr)
|
|
{
|
|
if (addr < 0x2000)
|
|
{
|
|
return VROM[(chr_reg_8k * 0x2000) + addr];
|
|
}
|
|
return base.ReadPPU(addr);
|
|
}
|
|
}
|
|
}
|