Path: blob/master/BizHawk.Emulation.Cores/CPUs/MOS 6502X/MOS6502X.cs
2 views
using System;
using System.IO;
using BizHawk.Common;
using BizHawk.Emulation.Common;
namespace BizHawk.Emulation.Cores.Components.M6502
{
public sealed partial class MOS6502X
{
public MOS6502X()
{
InitOpcodeHandlers();
Reset();
}
public bool BCD_Enabled = true;
public bool debug = false;
public bool throw_unhandled;
public void Reset()
{
A = 0;
X = 0;
Y = 0;
P = 0;
S = 0;
PC = 0;
TotalExecutedCycles = 0;
mi = 0;
opcode = 256;
iflag_pending = true;
RDY = true;
}
public void NESSoftReset()
{
opcode = VOP_RESET;
mi = 0;
iflag_pending = true;
FlagI = true;
}
public string TraceHeader
{
get { return "6502: PC, machine code, mnemonic, operands, registers (A, X, Y, P, SP), flags (NVTBDIZCR)"; }
}
public TraceInfo State(bool disassemble = true)
{
int notused;
return new TraceInfo
{
Disassembly = string.Format(
"{0:X4}: {1:X2} {2} ",
PC,
PeekMemory(PC),
disassemble ? Disassemble(PC, out notused) : "---").PadRight(26),
RegisterInfo = string.Format(
"A:{0:X2} X:{1:X2} Y:{2:X2} P:{3:X2} SP:{4:X2} Cy:{5} {6}{7}{8}{9}{10}{11}{12}{13}",
A,
X,
Y,
P,
S,
TotalExecutedCycles,
FlagN ? "N" : "n",
FlagV ? "V" : "v",
FlagT ? "T" : "t",
FlagB ? "B" : "b",
FlagD ? "D" : "d",
FlagI ? "I" : "i",
FlagZ ? "Z" : "z",
FlagC ? "C" : "c",
!RDY ? "R" : "r")
};
}
public bool AtStart { get { return opcode == VOP_Fetch1 || Microcode[opcode][mi] >= Uop.End; } }
public TraceInfo TraceState()
{
// only disassemble when we're at the beginning of an opcode
return State(AtStart);
}
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
}
// ==== 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 RDY;
public void SyncState(Serializer ser)
{
ser.BeginSection("MOS6502X");
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("RDY", ref RDY);
ser.Sync("TotalExecutedCycles", ref TotalExecutedCycles);
ser.Sync("opcode", ref opcode);
ser.Sync("opcode2", ref opcode2);
ser.Sync("opcode3", ref opcode3);
ser.Sync("ea", ref ea);
ser.Sync("alu_temp", ref alu_temp);
ser.Sync("mi", ref mi);
ser.Sync("iflag_pending", ref iflag_pending);
ser.Sync("interrupt_pending", ref interrupt_pending);
ser.Sync("branch_irq_hack", ref branch_irq_hack);
ser.Sync("rdy_freeze", ref rdy_freeze);
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>
public bool FlagC
{
get { return (P & 0x01) != 0; }
private set { P = (byte)((P & ~0x01) | (value ? 0x01 : 0x00)); }
}
/// <summary>Zero Flag</summary>
public bool FlagZ
{
get { return (P & 0x02) != 0; }
private 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>
public bool FlagD
{
get { return (P & 0x08) != 0; }
private set { P = (byte)((P & ~0x08) | (value ? 0x08 : 0x00)); }
}
/// <summary>Break Flag</summary>
public bool FlagB
{
get { return (P & 0x10) != 0; }
private set { P = (byte)((P & ~0x10) | (value ? 0x10 : 0x00)); }
}
/// <summary>T... Flag</summary>
public bool FlagT
{
get { return (P & 0x20) != 0; }
private set { P = (byte)((P & ~0x20) | (value ? 0x20 : 0x00)); }
}
/// <summary>Overflow Flag</summary>
public bool FlagV
{
get { return (P & 0x40) != 0; }
private set { P = (byte)((P & ~0x40) | (value ? 0x40 : 0x00)); }
}
/// <summary>Negative Flag</summary>
public bool FlagN
{
get { return (P & 0x80) != 0; }
private set { P = (byte)((P & ~0x80) | (value ? 0x80 : 0x00)); }
}
public int TotalExecutedCycles;
public Func<ushort, byte> ReadMemory;
public Func<ushort, byte> DummyReadMemory;
public Func<ushort, byte> PeekMemory;
public Action<ushort, byte> WriteMemory;
//this only calls when the first byte of an instruction is fetched.
public Action<ushort> OnExecFetch;
public void SetCallbacks
(
Func<ushort, byte> ReadMemory,
Func<ushort, byte> DummyReadMemory,
Func<ushort, byte> PeekMemory,
Action<ushort, byte> WriteMemory
)
{
this.ReadMemory = ReadMemory;
this.DummyReadMemory = DummyReadMemory;
this.PeekMemory = PeekMemory;
this.WriteMemory = WriteMemory;
}
public ushort ReadWord(ushort address)
{
byte l = ReadMemory(address);
byte h = ReadMemory(++address);
return (ushort)((h << 8) | l);
}
public ushort PeekWord(ushort address)
{
byte l = PeekMemory(address);
byte h = PeekMemory(++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));
}
// SO pin
public void SetOverflow()
{
FlagV = true;
}
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
};
}
}