From 46ff936d41c7cded598a45b7045c183e6cc12faf Mon Sep 17 00:00:00 2001
From: saxxonpike <saxxonpike@gmail.com>
Date: Thu, 15 Nov 2012 15:58:26 +0000
Subject: [PATCH] commodore64: 1541 disk drive CPU emulated when a D64 or G64
 is loaded, not attached to serial bus and no mechanical emulation yet

---
 BizHawk.Emulation/Computers/Commodore64/1541.cs     | 12 ++++++++++--
 .../Computers/Commodore64/C64.PeekPoke.cs           | 13 +++++++++++++
 BizHawk.Emulation/Computers/Commodore64/C64.cs      |  1 +
 BizHawk.Emulation/Computers/Commodore64/Cia.cs      |  2 ++
 4 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/BizHawk.Emulation/Computers/Commodore64/1541.cs b/BizHawk.Emulation/Computers/Commodore64/1541.cs
index b5f4ebedf4..4196cc9d7b 100644
--- a/BizHawk.Emulation/Computers/Commodore64/1541.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/1541.cs
@@ -49,6 +49,11 @@ namespace BizHawk.Emulation.Computers.Commodore64
 		public void HardReset()
 		{
 			cpu = new MOS6502X();
+			cpu.PC = (ushort)(Read(0xFFFC) + (Read(0xFFFD) << 8));
+			cpu.ReadMemory = Read;
+			cpu.WriteMemory = Write;
+			cpu.DummyReadMemory = Read;
+
 			ram = new byte[0x800];
 			via0 = new Via();
 			via1 = new Via();
@@ -60,8 +65,9 @@ namespace BizHawk.Emulation.Computers.Commodore64
 			disk = newDisk;
 		}
 
-		public byte Peek(ushort addr)
+		public byte Peek(int addr)
 		{
+			addr &= 0xFFFF;
 			if (addr < 0x0800)
 			{
 				return ram[addr];
@@ -83,10 +89,12 @@ namespace BizHawk.Emulation.Computers.Commodore64
 
 		public void PerformCycle()
 		{
+			cpu.ExecuteOne();
 		}
 
-		public void Poke(ushort addr, byte val)
+		public void Poke(int addr, byte val)
 		{
+			addr &= 0xFFFF;
 			if (addr < 0x0800)
 			{
 				ram[addr] = val;
diff --git a/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs b/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs
index 1b2287d4f1..c114799dcc 100644
--- a/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs
@@ -22,6 +22,13 @@ namespace BizHawk.Emulation.Computers.Commodore64
 			return (byte)((mem.colorRam[addr & 0x3FF] & 0xF) | mem.busData);
 		}
 
+		public byte PeekDiskDrive(int addr)
+		{
+			if (diskDriveAttached)
+				return diskDrive.Peek(addr);
+			return 0xFF;
+		}
+
 		public byte PeekMemory(ushort addr)
 		{
 			return mem.Peek(addr);
@@ -62,6 +69,12 @@ namespace BizHawk.Emulation.Computers.Commodore64
 			mem.colorRam[addr & 0x3FF] = (byte)(val & 0xF);
 		}
 
+		public void PokeDiskDrive(int addr, byte val)
+		{
+			if (diskDriveAttached)
+				diskDrive.Poke(addr, val);
+		}
+
 		public void PokeMemoryInt(int addr, byte val)
 		{
 			mem.Poke((ushort)(addr & 0xFFFF), val);
diff --git a/BizHawk.Emulation/Computers/Commodore64/C64.cs b/BizHawk.Emulation/Computers/Commodore64/C64.cs
index 0139966dc8..5ff3d25fce 100644
--- a/BizHawk.Emulation/Computers/Commodore64/C64.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/C64.cs
@@ -124,6 +124,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 			domains.Add(new MemoryDomain("SID", 0x20, Endian.Little, new Func<int, byte>(PeekSid), new Action<int, byte>(PokeSid)));
 			domains.Add(new MemoryDomain("VIC", 0x40, Endian.Little, new Func<int, byte>(PeekVic), new Action<int, byte>(PokeVic)));
 			domains.Add(new MemoryDomain("CRAM", 0x400, Endian.Little, new Func<int, byte>(PeekColorRAM), new Action<int, byte>(PokeColorRAM)));
+			domains.Add(new MemoryDomain("DISKRAM", 0x10000, Endian.Little, new Func<int, byte>(PeekDiskDrive), new Action<int, byte>(PokeDiskDrive)));
 			memoryDomains = domains.AsReadOnly();
 		}
 
diff --git a/BizHawk.Emulation/Computers/Commodore64/Cia.cs b/BizHawk.Emulation/Computers/Commodore64/Cia.cs
index 0e903e2524..69f45bb91b 100644
--- a/BizHawk.Emulation/Computers/Commodore64/Cia.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/Cia.cs
@@ -447,6 +447,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 					// reading this reg clears it
 					result = regs[0x0D];
 					regs[0x0D] = 0x00;
+					UpdateInterrupt();
 					return result;
 				default:
 					return regs[addr];
@@ -581,6 +582,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 					regs.EIALARM = ((intMask & 0x04) != 0x00);
 					regs.EISP = ((intMask & 0x08) != 0x00);
 					regs.EIFLAG = ((intMask & 0x10) != 0x00);
+					UpdateInterrupt();
 					break;
 				default:
 					regs[addr] = val;