commodore64: Add 6526 2-cycle timer delay, seems to pass more tests now. CPU Dataport inputs on lower 3 bits are always high now, may fix some paging issues. Fix joystick input so that only port A is affected on pure outputs.

BizHawk.Emulation/Computers/Commodore64/C64.Input.cs

@@ -97,9 +97,8 @@ namespace BizHawk.Emulation.Computers.Commodore64
 			}
 
 			inputAdapter0.Data = resultA;
-			inputAdapter1.Data = resultB;
+			inputAdapter1.Data = (byte)(joyB & resultB);
 			inputAdapter0.MaskWrite(joyB);
-			inputAdapter1.MaskWrite(joyA);
 		}
 	}
 }

BizHawk.Emulation/Computers/Commodore64/MOS/MOS6510.cs

@@ -21,6 +21,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 		private bool pinCharen;
 		private bool pinLoram;
 		private bool pinHiram;
+		private bool pinNMILast;
 		private byte portDir;
 		private bool unusedPin0;
 		private bool unusedPin1;
@@ -41,13 +42,16 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			cpu.WriteMemory = Write;
 
 			// configure data port defaults
-			portDir = 0x2F;
+			portDir = 0xEF;
 			SetPortData(0x37);
 
 			// todo: verify this value (I only know that unconnected bits fade after a number of cycles)
 			unusedPinTTLCycles = 40;
 			unusedPinTTL0 = 0;
 			unusedPinTTL1 = 0;
+
+			// NMI is high on startup (todo: verify)
+			pinNMILast = true;
 		}
 
 		public void HardReset()
@@ -73,7 +77,13 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			{
 				// the 6502 core expects active high
 				// so we reverse the polarity here
-				cpu.NMI = !(chips.cia1.IRQ & chips.cartPort.NMI);
+				bool thisNMI = (chips.cia1.IRQ & chips.cartPort.NMI);
+				if (!thisNMI && pinNMILast)
+					cpu.NMI = true;
+				else
+					cpu.NMI = false;
+				pinNMILast = thisNMI;
+
 				cpu.IRQ = !(chips.vic.IRQ && chips.cia0.IRQ && chips.cartPort.IRQ);
 				cpu.ExecuteOne();
 			}
@@ -105,7 +115,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 		public void Poke(int addr, byte val)
 		{
 			if (addr == 0x0000)
-				portDir = val;
+				SetPortDir(val);
 			else if (addr == 0x0001)
 				SetPortData(val);
 			else
@@ -182,7 +192,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			set
 			{
 				Console.WriteLine("CPU write DIR: val=" + C64Util.ToBinary(value, 8));
-				portDir = value;
+				SetPortDir(value);
 			}
 		}
 
@@ -202,6 +212,12 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			unusedPinTTL1 = unusedPinTTLCycles;
 		}
 
+		private void SetPortDir(byte val)
+		{
+			portDir = val;
+			SetPortData((byte)(PortData | ((byte)~val & 0x1F)));
+		}
+
 		// ------------------------------------
 	}
 }

BizHawk.Emulation/Computers/Commodore64/MOS/MOS6526.cs

@@ -61,6 +61,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 		private bool pinFlag;
 		private bool pinPC;
 		private byte sr;
+		private uint[] timerDelay;
 		private InMode[] timerInMode;
 		private OutMode[] timerOutMode;
 		private bool[] timerPortEnable;
@@ -82,6 +83,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			chipRegion = region;
 			enableIntTimer = new bool[2];
 			intTimer = new bool[2];
+			timerDelay = new uint[2];
 			timerInMode = new InMode[2];
 			timerOutMode = new OutMode[2];
 			timerPortEnable = new bool[2];
@@ -111,8 +113,16 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			if (timerPulse[1])
 				portData[1] &= PBOnMask[0];
 
+			if (timerDelay[0] == 0)
 				TimerRun(0);
+			else
+				timerDelay[0]--;
+
+			if (timerDelay[1] == 0)
 				TimerRun(1);
+			else
+				timerDelay[1]--;
+
 			intAlarm |= (
 				tod[0] == todAlarm[0] &&
 				tod[1] == todAlarm[1] &&
@@ -149,8 +159,8 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			intTimer[0] = false;
 			intTimer[1] = false;
 			sr = 0;
-			timerPortEnable[0] = false;
+			timerDelay[0] = 0;
-			timerPortEnable[1] = false;
+			timerDelay[1] = 0;
 			timerInMode[0] = InMode.Phase2;
 			timerInMode[1] = InMode.Phase2;
 			timerOn[0] = false;
@@ -402,6 +412,7 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 		private byte ReadRegister(ushort addr)
 		{
 			byte val = 0x00; //unused pin value
+			uint timerVal;
 
 			switch (addr)
 			{
@@ -418,16 +429,20 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 					val = portDir[1];
 					break;
 				case 0x4:
-					val = (byte)(timer[0] & 0xFF);
+					timerVal = ReadTimerValue(0);
+					val = (byte)(timerVal & 0xFF);
 					break;
 				case 0x5:
-					val = (byte)(timer[0] >> 8);
+					timerVal = ReadTimerValue(0);
+					val = (byte)(timerVal >> 8);
 					break;
 				case 0x6:
-					val = (byte)(timer[1] & 0xFF);
+					timerVal = ReadTimerValue(1);
+					val = (byte)(timerVal & 0xFF);
 					break;
 				case 0x7:
-					val = (byte)(timer[1] >> 8);
+					timerVal = ReadTimerValue(1);
+					val = (byte)(timerVal >> 8);
 					break;
 				case 0x8:
 					val = tod[0];
@@ -495,6 +510,21 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 			return val;
 		}
 
+		private uint ReadTimerValue(uint index)
+		{
+			if (timerOn[index])
+			{
+				if (timer[index] == 0)
+					return timerLatch[index];
+				else
+					return timer[index];
+			}
+			else
+			{
+				return timer[index];
+			}
+		}
+
 		public void Write(ushort addr, byte val)
 		{
 			Write(addr, val, 0xFF);
@@ -622,6 +652,8 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 						enableIntFlag = intReg;
 					break;
 				case 0xE:
+					if ((val & 0x01) != 0 && !timerOn[0])
+						timerDelay[0] = 2;
 					timerOn[0] = ((val & 0x01) != 0);
 					timerPortEnable[0] = ((val & 0x02) != 0);
 					timerOutMode[0] = ((val & 0x04) != 0) ? OutMode.Toggle : OutMode.Pulse;
@@ -631,6 +663,8 @@ namespace BizHawk.Emulation.Computers.Commodore64.MOS
 					todIn = ((val & 0x80) != 0);
 					break;
 				case 0xF:
+					if ((val & 0x01) != 0 && !timerOn[1])
+						timerDelay[1] = 2;
 					timerOn[1] = ((val & 0x01) != 0);
 					timerPortEnable[1] = ((val & 0x02) != 0);
 					timerOutMode[1] = ((val & 0x04) != 0) ? OutMode.Toggle : OutMode.Pulse;