116 lines
3.3 KiB
C#
116 lines
3.3 KiB
C#
//////////////////////////////////////////////////////////////////////////
|
|
// Mapper142 SMB2J //
|
|
//////////////////////////////////////////////////////////////////////////
|
|
using System;
|
|
using static VirtualNes.Core.CPU;
|
|
using static VirtualNes.MMU;
|
|
using BYTE = System.Byte;
|
|
using INT = System.Int32;
|
|
|
|
|
|
namespace VirtualNes.Core
|
|
{
|
|
public class Mapper142 : Mapper
|
|
{
|
|
BYTE prg_sel;
|
|
BYTE irq_enable;
|
|
INT irq_counter;
|
|
public Mapper142(NES parent) : base(parent)
|
|
{
|
|
}
|
|
|
|
public override void Reset()
|
|
|
|
{
|
|
prg_sel = 0;
|
|
irq_enable = 0;
|
|
irq_counter = 0;
|
|
|
|
SetPROM_8K_Bank(3, 0);
|
|
SetPROM_8K_Bank(7, 0x0F);
|
|
|
|
if (VROM_1K_SIZE != 0)
|
|
{
|
|
SetVROM_8K_Bank(0);
|
|
}
|
|
}
|
|
|
|
//void Mapper142::Write(WORD addr, BYTE data)
|
|
public override void Write(ushort addr, byte data)
|
|
{
|
|
switch (addr & 0xF000)
|
|
{
|
|
case 0x8000:
|
|
irq_counter = (irq_counter & 0xFFF0) | ((data & 0x0F) << 0);
|
|
break;
|
|
case 0x9000:
|
|
irq_counter = (irq_counter & 0xFF0F) | ((data & 0x0F) << 4);
|
|
break;
|
|
case 0xA000:
|
|
irq_counter = (irq_counter & 0xF0FF) | ((data & 0x0F) << 8);
|
|
break;
|
|
case 0xB000:
|
|
irq_counter = (irq_counter & 0x0FFF) | ((data & 0x0F) << 12);
|
|
break;
|
|
case 0xC000:
|
|
irq_enable = (byte)(data & 0x0F);
|
|
nes.cpu.ClrIRQ(IRQ_MAPPER);
|
|
break;
|
|
case 0xE000:
|
|
prg_sel = (byte)(data & 0x0F);
|
|
break;
|
|
case 0xF000:
|
|
switch (prg_sel)
|
|
{
|
|
case 1: SetPROM_8K_Bank(4, data & 0x0F); break;
|
|
case 2: SetPROM_8K_Bank(5, data & 0x0F); break;
|
|
case 3: SetPROM_8K_Bank(6, data & 0x0F); break;
|
|
case 4: SetPROM_8K_Bank(3, data & 0x0F); break;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
//void Mapper142::HSync(INT scanline)
|
|
public override void HSync(int scanline)
|
|
{
|
|
if (irq_enable != 0)
|
|
{
|
|
if (irq_counter > (0xFFFF - 113))
|
|
{
|
|
irq_counter = 0;
|
|
nes.cpu.SetIRQ(IRQ_MAPPER);
|
|
}
|
|
else
|
|
{
|
|
irq_counter += 113;
|
|
}
|
|
}
|
|
}
|
|
|
|
//void Mapper142::SaveState(LPBYTE p)
|
|
public override void SaveState(byte[] p)
|
|
{
|
|
p[0] = prg_sel;
|
|
p[0] = irq_enable;
|
|
//*(INT*)&p[2] = irq_counter;
|
|
BitConverter.GetBytes(irq_counter).CopyTo(p, 2);
|
|
}
|
|
|
|
//void Mapper142::LoadState(LPBYTE p)
|
|
public override void LoadState(byte[] p)
|
|
{
|
|
prg_sel = p[0];
|
|
irq_enable = p[1];
|
|
//irq_counter = *(INT*)&p[2];
|
|
irq_counter = BitConverter.ToInt32(p, 2);
|
|
}
|
|
public override bool IsStateSave()
|
|
{
|
|
return true;
|
|
}
|
|
|
|
|
|
}
|
|
}
|