AxibugEmuOnline/Core/VirtualNes.Core/Mapper/Mapper067.cs

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//////////////////////////////////////////////////////////////////////////
// Mapper067 SunSoft Mapper 3 //
//////////////////////////////////////////////////////////////////////////
using System;
using static VirtualNes.Core.CPU;
using static VirtualNes.MMU;
using BYTE = System.Byte;
using INT = System.Int32;
namespace VirtualNes.Core
{
public class Mapper067 : Mapper
{
BYTE irq_enable;
BYTE irq_occur;
BYTE irq_toggle;
INT irq_counter;
public Mapper067(NES parent) : base(parent)
{
}
public override void Reset()
{
irq_enable = 0;
irq_toggle = 0;
irq_counter = 0;
irq_occur = 0;
SetPROM_32K_Bank(0, 1, PROM_8K_SIZE - 2, PROM_8K_SIZE - 1);
SetVROM_4K_Bank(0, 0);
SetVROM_4K_Bank(4, VROM_4K_SIZE - 1);
uint crc = nes.rom.GetPROM_CRC();
if (crc == 0x7f2a04bf)
{ // For Fantasy Zone 2(J)
nes.SetRenderMethod(EnumRenderMethod.PRE_ALL_RENDER);
}
}
//void Mapper067::Write(WORD addr, BYTE data)
public override void Write(ushort addr, byte data)
{
switch (addr & 0xF800)
{
case 0x8800:
SetVROM_2K_Bank(0, data);
break;
case 0x9800:
SetVROM_2K_Bank(2, data);
break;
case 0xA800:
SetVROM_2K_Bank(4, data);
break;
case 0xB800:
SetVROM_2K_Bank(6, data);
break;
case 0xC800:
if (irq_toggle == 0)
{
irq_counter = (irq_counter & 0x00FF) | ((INT)data << 8);
}
else
{
irq_counter = (irq_counter & 0xFF00) | ((INT)data & 0xFF);
}
irq_toggle ^= 1;
irq_occur = 0;
nes.cpu.ClrIRQ(IRQ_MAPPER);
break;
case 0xD800:
irq_enable = (byte)(data & 0x10);
irq_toggle = 0;
irq_occur = 0;
nes.cpu.ClrIRQ(IRQ_MAPPER);
break;
case 0xE800:
data &= 0x03;
if (data == 0) SetVRAM_Mirror(VRAM_VMIRROR);
else if (data == 1) SetVRAM_Mirror(VRAM_HMIRROR);
else if (data == 2) SetVRAM_Mirror(VRAM_MIRROR4L);
else SetVRAM_Mirror(VRAM_MIRROR4H);
break;
case 0xF800:
SetPROM_16K_Bank(4, data);
break;
}
}
//void Mapper067::Clock(INT cycles)
public override void Clock(int cycles)
{
if (irq_enable != 0)
{
if ((irq_counter -= cycles) <= 0)
{
irq_enable = 0;
irq_occur = 0xFF;
irq_counter = 0xFFFF;
nes.cpu.SetIRQ(IRQ_MAPPER);
}
}
// if( irq_occur ) {
// nes.cpu.IRQ_NotPending();
// }
}
//void Mapper067::SaveState(LPBYTE p)
public override void SaveState(byte[] p)
{
p[0] = irq_enable;
p[1] = irq_occur;
p[2] = irq_toggle;
//*((INT*)&p[3]) = irq_counter;
BitConverter.GetBytes(irq_counter).CopyTo(p, 3);
}
//void Mapper067::LoadState(LPBYTE p)
public override void LoadState(byte[] p)
{
irq_enable = p[0];
irq_occur = p[1];
irq_toggle = p[2];
//irq_counter = *((INT*)&p[3]);
irq_counter = BitConverter.ToInt32(p, 3);
}
public override bool IsStateSave()
{
return true;
}
}
}