using System;
using System.Globalization;
using System.IO;
namespace BizHawk.Emulation.CPUs.M6502
{
public sealed partial class MOS6502
{
public MOS6502()
{
//InitTableNZ();
Reset();
}
/*
private byte[] TableNZ;
private void InitTableNZ()
{
TableNZ = new byte[256];
for (int i = 0; i < 256; i++)
{
byte b = 0;
if (i == 0) b |= 0x02;
if (i > 127) b |= 0x80;
TableNZ[i] = b;
}
}*/
public bool debug;
public bool throw_unhandled;
public void Reset()
{
A = 0;
X = 0;
Y = 0;
P = 0;
S = 0;
PC = 0;
PendingCycles = 0;
TotalExecutedCycles = 0;
}
public string State()
{
int notused;
string a = string.Format("{0:X4} {1:X2} {2} ", PC, ReadMemory(PC), Disassemble(PC, out notused)).PadRight(30);
string b = string.Format("A:{0:X2} X:{1:X2} Y:{2:X2} P:{3:X2} SP:{4:X2} Cy:{5}", A, X, Y, P, S, TotalExecutedCycles);
string val = a + b + " ";
if (FlagN) val = val + "N";
if (FlagV) val = val + "V";
if (FlagT) val = val + "T";
if (FlagB) val = val + "B";
if (FlagD) val = val + "D";
if (FlagI) val = val + "I";
if (FlagZ) val = val + "Z";
if (FlagC) val = val + "C";
return val;
}
public const ushort NMIVector = 0xFFFA;
public const ushort ResetVector = 0xFFFC;
public const ushort BRKVector = 0xFFFE;
public const ushort IRQVector = 0xFFFE;
enum ExceptionType
{
BRK, NMI, IRQ
}
void TriggerException(ExceptionType type)
{
if (type == ExceptionType.BRK)
PC++;
WriteMemory((ushort)(S-- + 0x100), (byte)(PC >> 8));
WriteMemory((ushort)(S-- + 0x100), (byte)PC);
FlagB = type == ExceptionType.BRK;
WriteMemory((ushort)(S-- + 0x100), P);
FlagI = true;
switch (type)
{
case ExceptionType.NMI:
PC = ReadWord(NMIVector);
break;
case ExceptionType.IRQ:
PC = ReadWord(IRQVector);
break;
case ExceptionType.BRK:
PC = ReadWord(BRKVector);
break;
default: throw new Exception();
}
PendingCycles -= 7;
}
// ==== CPU State ====
public byte A;
public byte X;
public byte Y;
public byte P;
public ushort PC;
public byte S;
public bool IRQ;
public bool NMI;
public bool CLI_Pending;
public bool SEI_Pending;
public void SyncState(Serializer ser)
{
ser.BeginSection("MOS6502");
ser.Sync("A", ref A);
ser.Sync("X", ref X);
ser.Sync("Y", ref Y);
ser.Sync("P", ref P);
ser.Sync("PC", ref PC);
ser.Sync("S", ref S);
ser.Sync("NMI", ref NMI);
ser.Sync("IRQ", ref IRQ);
ser.Sync("CLI_Pending", ref CLI_Pending);
ser.Sync("SEI_Pending", ref SEI_Pending);
ser.Sync("TotalExecutedCycles", ref TotalExecutedCycles);
ser.Sync("PendingCycles", ref PendingCycles);
ser.EndSection();
}
public void SaveStateBinary(BinaryWriter writer) { SyncState(Serializer.CreateBinaryWriter(writer)); }
public void LoadStateBinary(BinaryReader reader) { SyncState(Serializer.CreateBinaryReader(reader)); }
// ==== End State ====
/// <summary>Carry Flag</summary>
private bool FlagC
{
get { return (P & 0x01) != 0; }
set { P = (byte)((P & ~0x01) | (value ? 0x01 : 0x00)); }
}
/// <summary>Zero Flag</summary>
private bool FlagZ
{
get { return (P & 0x02) != 0; }
set { P = (byte)((P & ~0x02) | (value ? 0x02 : 0x00)); }
}
/// <summary>Interrupt Disable Flag</summary>
public bool FlagI
{
get { return (P & 0x04) != 0; }
set { P = (byte)((P & ~0x04) | (value ? 0x04 : 0x00)); }
}
/// <summary>Decimal Mode Flag</summary>
private bool FlagD
{
get { return (P & 0x08) != 0; }
set { P = (byte)((P & ~0x08) | (value ? 0x08 : 0x00)); }
}
/// <summary>Break Flag</summary>
private bool FlagB
{
get { return (P & 0x10) != 0; }
set { P = (byte)((P & ~0x10) | (value ? 0x10 : 0x00)); }
}
/// <summary>T... Flag</summary>
private bool FlagT
{
get { return (P & 0x20) != 0; }
set { P = (byte)((P & ~0x20) | (value ? 0x20 : 0x00)); }
}
/// <summary>Overflow Flag</summary>
private bool FlagV
{
get { return (P & 0x40) != 0; }
set { P = (byte)((P & ~0x40) | (value ? 0x40 : 0x00)); }
}
/// <summary>Negative Flag</summary>
private bool FlagN
{
get { return (P & 0x80) != 0; }
set { P = (byte)((P & ~0x80) | (value ? 0x80 : 0x00)); }
}
public int TotalExecutedCycles;
public int PendingCycles;
public Func<ushort, byte> ReadMemory;
public Action<ushort, byte> WriteMemory;
public void UnregisterMemoryMapper()
{
ReadMemory = null;
WriteMemory = null;
}
public ushort ReadWord(ushort address)
{
byte l = ReadMemory(address);
byte h = ReadMemory(++address);
return (ushort)((h << 8) | l);
}
private void WriteWord(ushort address, ushort value)
{
byte l = (byte)(value & 0xFF);
byte h = (byte)(value >> 8);
WriteMemory(address, l);
WriteMemory(++address, h);
}
private ushort ReadWordPageWrap(ushort address)
{
ushort highAddress = (ushort)((address & 0xFF00) + ((address + 1) & 0xFF));
return (ushort)(ReadMemory(address) | (ReadMemory(highAddress) << 8));
}
private static readonly byte[] TableNZ =
{
0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80
};
}
}
