Essgee.Unity/Assets/Plugins/Essgee/Emulation/Cartridges/Nintendo/MBC5Cartridge.cs
2025-01-02 17:55:16 +08:00

145 lines
2.9 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Essgee.Exceptions;
using Essgee.Utilities;
namespace Essgee.Emulation.Cartridges.Nintendo
{
// TODO: rumble?
public class MBC5Cartridge : IGameBoyCartridge
{
public event EventHandler<EventArgs> EnableRumble;
protected virtual void OnEnableRumble(EventArgs e) { EnableRumble?.Invoke(this, EventArgs.Empty); }
byte[] romData, ramData;
bool hasBattery, hasRumble;
ushort romBank;
byte ramBank;
bool ramEnable;
public MBC5Cartridge(int romSize, int ramSize)
{
romData = new byte[romSize];
ramData = new byte[ramSize];
romBank = 1;
ramBank = 0;
ramEnable = false;
hasBattery = false;
hasRumble = false;
}
public void LoadRom(byte[] data)
{
Buffer.BlockCopy(data, 0, romData, 0, Math.Min(data.Length, romData.Length));
}
public void LoadRam(byte[] data)
{
Buffer.BlockCopy(data, 0, ramData, 0, Math.Min(data.Length, ramData.Length));
}
public byte[] GetRomData()
{
return romData;
}
public byte[] GetRamData()
{
return ramData;
}
public bool IsRamSaveNeeded()
{
return hasBattery;
}
public ushort GetLowerBound()
{
return 0x0000;
}
public ushort GetUpperBound()
{
return 0x7FFF;
}
public void SetCartridgeConfig(bool battery, bool rtc, bool rumble)
{
hasBattery = battery;
hasRumble = rumble;
}
public void Step(int clockCyclesInStep)
{
/* Nothing to do */
}
public byte Read(ushort address)
{
if (address >= 0x0000 && address <= 0x3FFF)
{
return romData[address & 0x3FFF];
}
else if (address >= 0x4000 && address <= 0x7FFF)
{
return romData[(romBank << 14) | (address & 0x3FFF)];
}
else if (address >= 0xA000 && address <= 0xBFFF)
{
if (ramEnable && ramData.Length != 0)
return ramData[(ramBank << 13) | (address & 0x1FFF)];
else
return 0xFF;
}
else
return 0xFF;
}
public void Write(ushort address, byte value)
{
if (address >= 0x0000 && address <= 0x1FFF)
{
ramEnable = (value & 0x0F) == 0x0A;
}
else if (address >= 0x2000 && address <= 0x2FFF)
{
romBank = (ushort)((romBank & 0x0100) | value);
romBank &= (ushort)((romData.Length >> 14) - 1);
}
else if (address >= 0x3000 && address <= 0x3FFF)
{
romBank = (ushort)((romBank & 0x00FF) | ((value & 0x01) << 8));
romBank &= (ushort)((romData.Length >> 14) - 1);
}
else if (address >= 0x4000 && address <= 0x5FFF)
{
if (hasRumble)
{
if ((value & 0x08) == 0x08) OnEnableRumble(EventArgs.Empty);
ramBank = (byte)(value & 0x07);
ramBank %= (byte)(ramData.Length >> 13);
}
else
{
ramBank = (byte)(value & 0x0F);
ramBank %= (byte)(ramData.Length >> 13);
}
}
else if (address >= 0xA000 && address <= 0xBFFF)
{
if (ramEnable && ramData.Length != 0)
ramData[(ramBank << 13) | (address & 0x1FFF)] = value;
}
}
}
}