nes-add vrc7 and fix irq bugs in vrc2,4,6

BizHawk.Emulation/BizHawk.Emulation.csproj

@@ -139,6 +139,7 @@
     </Compile>
     <Compile Include="Consoles\Nintendo\NES\Boards\VRC2_4.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\VRC6.cs" />
+    <Compile Include="Consoles\Nintendo\NES\Boards\VRC7.cs" />
     <Compile Include="Consoles\Nintendo\NES\Core.cs" />
     <Compile Include="Consoles\Nintendo\NES\iNES.cs" />
     <Compile Include="Consoles\Nintendo\NES\NES.cs" />

BizHawk.Emulation/Consoles/Nintendo/Docs/compatibility.txt

@@ -69,7 +69,7 @@ Open bus and bus conflict emulation is not considered complete or thorough in an
 079	NINA-06		Complete
 080	Misc (J)	Nothing
 082	Misc (J)	Nothing
-085	VRC7		Needed (lagrange point)
+085	VRC7		Decent (no OPL sound)
 086	Misc (J)	Started (One game I tried didn't work but also didn't match the sha1 (but worked in FCEUX)
 087	Misc (J)	Complete
 088	Misc (J)	Nothing

BizHawk.Emulation/Consoles/Nintendo/NES/Boards/VRC2_4.cs

@@ -5,7 +5,7 @@ using System.Diagnostics;
 namespace BizHawk.Emulation.Consoles.Nintendo
 {
 	//mapper 21 + 22 + 23 + 25 (docs largely in 021.txt for VRC4 and 22.txt for VRC2)
-	//If you change any of the IRQ logic here, be sure to change it in VRC4 as well.
+	//If you change any of the IRQ logic here, be sure to change it in VRC 6/7 as well.
 	public class VRC2_4 : NES.NESBoardBase
 	{
 		//configuration
@@ -266,6 +266,10 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 						//disabled
 						irq_enabled = false;
 					}
+
+					//acknowledge
+					irq_pending = false;
+
 					SyncIRQ();
 
 					break;
@@ -299,6 +303,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 
 			if (irq_mode)
 			{
+				throw new InvalidOperationException("needed a test case for this; you found one!");
 				ClockIRQ();
 			}
 			else

BizHawk.Emulation/Consoles/Nintendo/NES/Boards/VRC6.cs

@@ -5,7 +5,7 @@ using System.Diagnostics;
 namespace BizHawk.Emulation.Consoles.Nintendo
 {
 	//mapper 24 + 26
-	//If you change any of the IRQ logic here, be sure to change it in VRC4 as well.
+	//If you change any of the IRQ logic here, be sure to change it in VRC 2/4/7 as well.
 	public class VRC6 : NES.NESBoardBase
 	{
 		//configuration
@@ -198,6 +198,10 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 						//disabled
 						irq_enabled = false;
 					}
+
+					//acknowledge
+					irq_pending = false;
+
 					SyncIRQ();
 
 					break;
@@ -228,6 +232,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 
 			if (irq_mode)
 			{
+				throw new InvalidOperationException("needed a test case for this; you found one!");
 				ClockIRQ();
 			}
 			else

BizHawk.Emulation/Consoles/Nintendo/NES/Boards/VRC7.cs

@@ -0,0 +1,224 @@
+using System;
+using System.IO;
+using System.Diagnostics;
+
+namespace BizHawk.Emulation.Consoles.Nintendo
+{
+	//mapper 85
+	//If you change any of the IRQ logic here, be sure to change it in VRC 2/4/6 as well.
+	public class VRC7 : NES.NESBoardBase
+	{
+		//configuration
+		int prg_bank_mask_8k, chr_bank_mask_1k;
+		Func<int, int> remap;
+
+		//state
+		ByteBuffer prg_banks_8k = new ByteBuffer(4);
+		ByteBuffer chr_banks_1k = new ByteBuffer(8);
+		bool irq_mode;
+		bool irq_enabled, irq_pending, irq_autoen;
+		byte irq_reload;
+		byte irq_counter;
+		int irq_prescaler;
+
+		public override void Dispose()
+		{
+			base.Dispose();
+			prg_banks_8k.Dispose();
+			chr_banks_1k.Dispose();
+		}
+
+		public override void SyncState(Serializer ser)
+		{
+			base.SyncState(ser);
+			ser.Sync("prg_banks_8k", ref prg_banks_8k);
+			ser.Sync("chr_banks_1k", ref chr_banks_1k);
+			ser.Sync("irq_mode", ref irq_mode);
+			ser.Sync("irq_enabled", ref irq_enabled);
+			ser.Sync("irq_pending", ref irq_pending);
+			ser.Sync("irq_autoen", ref irq_autoen);
+			ser.Sync("irq_reload", ref irq_reload);
+			ser.Sync("irq_counter", ref irq_counter);
+			ser.Sync("irq_prescaler", ref irq_prescaler);
+		}
+
+		void SyncIRQ()
+		{
+			NES.irq_cart = (irq_pending && irq_enabled);
+		}
+
+		public override bool Configure(NES.EDetectionOrigin origin)
+		{
+			switch (Cart.board_type)
+			{
+				case "KONAMI-VRC-7":
+					AssertPrg(128,512); AssertChr(0,128); AssertVram(0,8); AssertWram(0,8);
+					break;
+				default:
+					return false;
+			}
+
+			if (Cart.pcb == "353429")
+				//tiny toons 2
+				remap = (addr) => ((addr & 0xF000) | ((addr & 0x8) >> 3));
+			else if(Cart.pcb == "352402")
+				//lagrange point
+				remap = (addr) => ((addr & 0xF000) | ((addr & 0x10) >> 4));
+			else throw new Exception("Unknown PCB type for VRC7");
+
+			prg_bank_mask_8k = Cart.prg_size / 8 - 1;
+			chr_bank_mask_1k = Cart.chr_size - 1;
+
+			SetMirrorType(EMirrorType.Vertical);
+
+			prg_banks_8k[3] = (byte)(0xFF & prg_bank_mask_8k);
+
+			return true;
+		}
+		public override byte ReadPRG(int addr)
+		{
+			int bank_8k = addr >> 13;
+			int ofs = addr & ((1 << 13) - 1);
+			bank_8k = prg_banks_8k[bank_8k];
+			addr = (bank_8k << 13) | ofs;
+			return ROM[addr];
+		}
+
+		int Map_PPU(int addr)
+		{
+			int bank_1k = addr >> 10;
+			int ofs = addr & ((1 << 10) - 1);
+			bank_1k = chr_banks_1k[bank_1k];
+			addr = (bank_1k << 10) | ofs;
+			return addr;
+		}
+
+		public override byte ReadPPU(int addr)
+		{
+			if (addr < 0x2000)
+			{
+				addr = Map_PPU(addr);
+				if (Cart.vram_size != 0)
+					return base.ReadPPU(addr);
+				else return VROM[addr];
+			}
+			else return base.ReadPPU(addr);
+		}
+
+		public override void WritePPU(int addr, byte value)
+		{
+			if (addr < 0x2000)
+			{
+				base.WritePPU(Map_PPU(addr),value);
+			}
+			else base.WritePPU(addr, value);
+		}
+
+		public override void WritePRG(int addr, byte value)
+		{
+			//Console.WriteLine("    mapping {0:X4} = {1:X2}", addr, value);
+			addr = remap(addr);
+			//Console.WriteLine("- remapping {0:X4} = {1:X2}", addr, value);
+			switch (addr)
+			{
+				case 0x0000: prg_banks_8k[0] = (byte)(value & prg_bank_mask_8k); break;
+				case 0x0001: prg_banks_8k[1] = (byte)(value & prg_bank_mask_8k); break;
+				case 0x1000: prg_banks_8k[2] = (byte)(value & prg_bank_mask_8k); break;
+
+				case 0x1001:
+					//sound address port
+					break;
+				case 0x1003:
+					//sound data port
+					//TODO - remap will break this
+					break;
+
+					//a bit creepy to mask this for lagrange point which has no VROM, but the mask will be 0xFFFFFFFF so its OK
+				case 0x2000: chr_banks_1k[0] = (byte)(value & chr_bank_mask_1k); break;
+				case 0x2001: chr_banks_1k[1] = (byte)(value & chr_bank_mask_1k); break;
+				case 0x3000: chr_banks_1k[2] = (byte)(value & chr_bank_mask_1k); break;
+				case 0x3001: chr_banks_1k[3] = (byte)(value & chr_bank_mask_1k); break;
+				case 0x4000: chr_banks_1k[4] = (byte)(value & chr_bank_mask_1k); break;
+				case 0x4001: chr_banks_1k[5] = (byte)(value & chr_bank_mask_1k); break;
+				case 0x5000: chr_banks_1k[6] = (byte)(value & chr_bank_mask_1k); break;
+				case 0x5001: chr_banks_1k[7] = (byte)(value & chr_bank_mask_1k); break;
+
+				case 0x6000:
+					switch (value & 3)
+					{
+						case 0: SetMirrorType(NES.NESBoardBase.EMirrorType.Vertical); break;
+						case 1: SetMirrorType(NES.NESBoardBase.EMirrorType.Horizontal); break;
+						case 2: SetMirrorType(NES.NESBoardBase.EMirrorType.OneScreenA); break;
+						case 3: SetMirrorType(NES.NESBoardBase.EMirrorType.OneScreenB); break;
+					}
+					break;
+
+				case 0x6001: //(reload)
+					irq_reload = value;
+					break;
+				case 0x7000: //(control)
+					irq_mode = value.Bit(2);
+					irq_autoen = value.Bit(0);
+
+					if (value.Bit(1))
+					{
+						//enabled
+						irq_enabled = true;
+						irq_counter = irq_reload;
+						irq_prescaler = 341;
+					}
+					else
+					{
+						//disabled
+						irq_enabled = false;
+					}
+
+					//acknowledge
+					irq_pending = false;
+
+					SyncIRQ();
+
+					break;
+				
+				case 0x7001: //(ack)
+					irq_pending = false;
+					irq_enabled = irq_autoen;
+					SyncIRQ();
+					break;
+			}
+		}
+
+		void ClockIRQ()
+		{
+			if (irq_counter == 0xFF)
+			{
+				irq_pending = true;
+				irq_counter = irq_reload;
+				SyncIRQ();
+			}
+			else
+				irq_counter++;
+		}
+
+		public override void ClockPPU()
+		{
+			if (!irq_enabled) return;
+
+			if (irq_mode)
+			{
+				throw new InvalidOperationException("needed a test case for this; you found one!");
+				ClockIRQ();
+			}
+			else
+			{
+				irq_prescaler--;
+				if (irq_prescaler == 0)
+				{
+					irq_prescaler += 341;
+					ClockIRQ();
+				}
+			}
+		}
+
+	}
+}