BizHawk/BizHawk.Emulation.Cores/Computers/Commodore64/Cartridge/Mapper0012.cs

95 lines
2.1 KiB
C#

using System;
using System.Collections.Generic;
using BizHawk.Common;
namespace BizHawk.Emulation.Cores.Computers.Commodore64.Cartridge
{
internal sealed class Mapper0012 : CartridgeDevice
{
private readonly int[] _bankMain;
private readonly int[][] _bankHigh;
private int[] _bankHighSelected;
private int _bankIndex;
// Zaxxon and Super Zaxxon cartridges
// - read to 8xxx selects bank 0 in A000-BFFF
// - read to 9xxx selects bank 1 in A000-BFFF
public Mapper0012(IList<int> newAddresses, IList<int> newBanks, IList<int[]> newData)
{
_bankMain = new int[0x2000];
_bankHigh = new int[2][];
var dummyBank = new int[0x2000];
// create dummy bank just in case
for (var i = 0; i < 0x2000; i++)
{
dummyBank[i] = 0xFF;
}
_bankHigh[0] = dummyBank;
_bankHigh[1] = dummyBank;
// load in the banks
for (var i = 0; i < newAddresses.Count; i++)
{
if (newAddresses[i] == 0x8000)
{
Array.Copy(newData[i], _bankMain, 0x1000);
}
else if ((newAddresses[i] == 0xA000 || newAddresses[i] == 0xE000) && newBanks[i] < 2)
{
_bankHigh[newBanks[i]] = newData[i];
}
}
// mirror the main rom from 8000 to 9000
Array.Copy(_bankMain, 0x0000, _bankMain, 0x1000, 0x1000);
// set both pins low for 16k rom config
pinExRom = false;
pinGame = false;
}
protected override void SyncStateInternal(Serializer ser)
{
ser.Sync("BankHighSelected", ref _bankHighSelected, useNull: false);
ser.Sync("BankIndex", ref _bankIndex);
}
public override int Peek8000(int addr)
{
return _bankMain[addr];
}
public override int PeekA000(int addr)
{
return _bankHighSelected[addr];
}
public override int Read8000(int addr)
{
_bankIndex = (addr & 0x1000) >> 12;
_bankHighSelected = _bankHigh[_bankIndex];
return _bankMain[addr];
}
public override int ReadA000(int addr)
{
return _bankHighSelected[addr];
}
public override void SyncState(Serializer ser)
{
base.SyncState(ser);
if (ser.IsReader)
{
_bankHighSelected = _bankHigh[_bankIndex];
}
}
}
}