AxibugEmuOnline/AxibugEmuOnline.Client/Assets/VirtualNes.Core/Mapper/Mapper017.cs

using static VirtualNes.MMU;
using static VirtualNes.Core.CPU;
using INT = System.Int32;
using BYTE = System.Byte;
using Codice.CM.Client.Differences;

namespace VirtualNes.Core
{
	public class Mapper017 : Mapper
	{
		BYTE irq_enable;
		INT irq_counter;
		INT irq_latch;
		public Mapper017(NES parent) : base(parent)
		{
		}


		public override void Reset()
		{
			SetPROM_32K_Bank(0, 1, PROM_8K_SIZE - 2, PROM_8K_SIZE - 1);

			if (VROM_1K_SIZE != 0)
			{
				SetVROM_8K_Bank(0);
			}

			irq_enable = 0;
			irq_counter = 0;
			irq_latch = 0;
		}

		//void Mapper017::WriteLow(WORD addr, BYTE data)
		public override void WriteLow(ushort addr, byte data)
		{
			switch (addr)
			{
				case 0x42FE:
					if ((data & 0x10) != 0) SetVRAM_Mirror(VRAM_MIRROR4H);
					else SetVRAM_Mirror(VRAM_MIRROR4L);
					break;
				case 0x42FF:
					if ((data & 0x10) != 0) SetVRAM_Mirror(VRAM_HMIRROR);
					else SetVRAM_Mirror(VRAM_VMIRROR);
					break;

				case 0x4501:
					irq_enable = 0;
					nes.cpu.ClrIRQ(IRQ_MAPPER);
					break;
				case 0x4502:
					irq_latch = (irq_latch & 0xFF00) | data;
					break;
				case 0x4503:
					irq_latch = (irq_latch & 0x00FF) | ((INT)data << 8);
					irq_counter = irq_latch;
					irq_enable = 0xFF;
					break;

				case 0x4504:
				case 0x4505:
				case 0x4506:
				case 0x4507:
					SetPROM_8K_Bank((byte)(addr & 0x07), data);
					break;

				case 0x4510:
				case 0x4511:
				case 0x4512:
				case 0x4513:
				case 0x4514:
				case 0x4515:
				case 0x4516:
				case 0x4517:
					SetVROM_1K_Bank((byte)(addr & 0x07), data);
					break;

				default:
					base.WriteLow(addr, data);
					break;
			}
		}

		//void Mapper017::HSync(INT scanline)
		public override void HSync(int scanline)
		{
			if (irq_enable != 0)
			{
				if (irq_counter >= 0xFFFF - 113)
				{
					nes.cpu.SetIRQ(IRQ_MAPPER);
					//			nes.cpu.IRQ();
					//			irq_counter = 0;
					//			irq_enable = 0;
					irq_counter &= 0xFFFF;
				}
				else
				{
					irq_counter += 113;
				}
			}
		}

		//void Mapper017::SaveState(LPBYTE p)
		public override void SaveState(byte[] p)
		{
			//p[0] = irq_enable;
			//*(INT*)&p[1] = irq_counter;
			//*(INT*)&p[5] = irq_latch;
		}

		//void Mapper017::LoadState(LPBYTE p)
		public override void LoadState(byte[] p)
		{
			//irq_enable = p[0];
			//irq_counter = *(INT*)&p[1];
			//irq_latch = *(INT*)&p[5];
		}


		public override bool IsStateSave()
		{
			return true;
		}

	}
}