AxibugEmuOnline/AxibugEmuOnline.Client/Assets/VirtualNes.Core/Mapper/Mapper199.cs

//////////////////////////////////////////////////////////////////////////
// Mapper199  WaiXingTypeG Base ON Nintendo MMC3                        //
//////////////////////////////////////////////////////////////////////////
using static VirtualNes.MMU;
using static VirtualNes.Core.CPU;
using INT = System.Int32;
using BYTE = System.Byte;
using System;
using Codice.CM.Client.Differences;

namespace VirtualNes.Core
{
    public class Mapper199 : Mapper
    {
		BYTE[] reg = new byte[8];
		BYTE[] prg = new byte[4];
		BYTE[] chr = new byte[8];
		BYTE we_sram;

		BYTE irq_type;
		BYTE irq_enable;
		BYTE irq_counter;
		BYTE irq_latch;
		BYTE irq_request;
		public Mapper199(NES parent) : base(parent)
        {
        }

        public override void Reset()
		{
			for (INT i = 0; i < 8; i++)
			{
				reg[i] = 0x00;
				chr[i] = (byte)i;
			}
			prg[0] = 0x00;
			prg[1] = 0x01;
			prg[2] = 0x3e;
			prg[3] = 0x3f;
			SetBank_CPU();
			SetBank_PPU();

			we_sram = 0;
			irq_enable = irq_counter = irq_latch = irq_request = 0;


			uint crcP = nes.rom.GetPROM_CRC();
			uint crcV = nes.rom.GetVROM_CRC();

			if ((crcP == 0xE80D8741) || (crcV == 0x3846520D))
			{//ÍâÐÇ°ÔÍõµÄ´ó½
				nes.SetRenderMethod( EnumRenderMethod.POST_ALL_RENDER);
			}
		}


		//BYTE Mapper199::ReadLow(WORD addr)
		public override byte ReadLow(ushort addr)
		{
			if (addr >= 0x5000 && addr <= 0x5FFF)
			{
				return XRAM[addr - 0x4000];
			}
			else
			{
				return base.ReadLow(addr);
			}
		}

		//void Mapper199::WriteLow(WORD addr, BYTE data)
		public override void WriteLow(ushort addr, byte data)
		{
			if (addr >= 0x5000 && addr <= 0x5FFF)
			{
				XRAM[addr - 0x4000] = data;
			}
			else
			{
				base.WriteLow(addr, data);
			}
		}

		//void Mapper199::Write(WORD addr, BYTE data)
		public override void Write(ushort addr, byte data)
		{
			//DEBUGOUT( "MPRWR A=%04X D=%02X L=%3d CYC=%d\n", addr&0xFFFF, data&0xFF, nes.GetScanline(), nes.cpu.GetTotalCycles() );

			switch (addr & 0xE001)
			{
				case 0x8000:
					reg[0] = data;
					SetBank_CPU();
					SetBank_PPU();
					break;
				case 0x8001:
					reg[1] = data;

					switch (reg[0] & 0x0f)
					{
						case 0x00: chr[0] = data; SetBank_PPU(); break;
						case 0x01: chr[2] = data; SetBank_PPU(); break;
						case 0x02:
						case 0x03:
						case 0x04:
						case 0x05: chr[(reg[0] & 0x07) + 2] = data; SetBank_PPU(); break;
						case 0x06:
						case 0x07:
						case 0x08:
						case 0x09: prg[(reg[0] & 0x0f) - 6] = data; SetBank_CPU(); break;
						case 0x0A: chr[1] = data; SetBank_PPU(); break;
						case 0x0B: chr[3] = data; SetBank_PPU(); break;
					}
					break;
				case 0xA000:
					reg[2] = data;
					//if( !nes.rom.Is4SCREEN() ) 
					{
						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 0xA001:
					reg[3] = data;
					break;
				case 0xC000:
					reg[4] = data;
					irq_counter = data;
					irq_request = 0;
					break;
				case 0xC001:
					reg[5] = data;
					irq_latch = data;
					irq_request = 0;
					break;
				case 0xE000:
					reg[6] = data;
					irq_enable = 0;
					irq_request = 0;
					nes.cpu.ClrIRQ(IRQ_MAPPER);
					break;
				case 0xE001:
					reg[7] = data;
					irq_enable = 1;
					irq_request = 0;
					break;
			}

		}

		//void Mapper199::HSync(INT scanline)
		public override void HSync(int scanline)
		{
			if ((scanline >= 0 && scanline <= 239))
			{
				if (nes.ppu.IsDispON())
				{
					if (irq_enable != 0 && irq_request == 0)
					{
						if (scanline == 0)
						{
							if (irq_counter != 0)
							{
								irq_counter--;
							}
						}
						if ((irq_counter--) == 0)
						{
							irq_request = 0xFF;
							irq_counter = irq_latch;
							nes.cpu.SetIRQ(IRQ_MAPPER);
						}
					}
				}
			}
		}

		void SetBank_CPU()
		{
			SetPROM_8K_Bank(4, prg[0 ^ (reg[0] >> 5 & ~(0 << 1) & 2)]);
			SetPROM_8K_Bank(5, prg[1 ^ (reg[0] >> 5 & ~(1 << 1) & 2)]);
			SetPROM_8K_Bank(6, prg[2 ^ (reg[0] >> 5 & ~(2 << 1) & 2)]);
			SetPROM_8K_Bank(7, prg[3 ^ (reg[0] >> 5 & ~(3 << 1) & 2)]);
		}

		void SetBank_PPU()
		{
			//unsigned int bank = (reg[0] & 0x80) >> 5;
			int bank = (reg[0] & 0x80) >> 5;
			for (int x = 0; x < 8; x++)
			{
				if (chr[x] <= 7)
				{
					SetCRAM_1K_Bank((byte)(x ^ bank), chr[x]);
				}
				else
				{
					SetVROM_1K_Bank((byte)(x ^ bank), chr[x]);
				}
			}
		}

		//void Mapper199::SaveState(LPBYTE p)
		public override void SaveState(byte[] p)
		{
			for (INT i = 0; i < 8; i++)
			{
				p[i] = reg[i];
				p[10 + i] = chr[i];
			}

			p[8] = prg[0];
			p[9] = prg[1];
			p[18] = irq_enable;
			p[19] = irq_counter;
			p[20] = irq_latch;
			p[21] = irq_request;
			p[22] = prg[2];
			p[23] = prg[3];
		}

		//void Mapper199::LoadState(LPBYTE p)
		public override void LoadState(byte[] p)
		{
			for (INT i = 0; i < 8; i++)
			{
				reg[i] = p[i];
				chr[i] = p[10 + i];
			}
			prg[0] = p[8];
			prg[1] = p[9];
			irq_enable = p[18];
			irq_counter = p[19];
			irq_latch = p[20];
			irq_request = p[21];
			prg[2] = p[22];
			prg[3] = p[23];
		}

		public override bool IsStateSave()
		{
			return true;
		}
	}
}