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using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
namespace Noddybox.Emulation.EightBit.Z80
{
/// <summary>
/// Provides an implementation of a Zilog Z80 processor.
/// </summary>
public partial class Z80Cpu : ICpu
{
#region Private types
[Flags]
private enum Z80Flags
{
None = 0x00,
Carry = 0x01,
Neg = 0x02,
PV = 0x04,
Hidden3 = 0x08,
HalfCarry = 0x10,
Hidden5 = 0x20,
Zero = 0x40,
Sign = 0x80
};
#endregion
#region Private data
// Lookup tables
//
private Z80Flags[] PSZtable = new Z80Flags[512];
private Z80Flags[] SZtable = new Z80Flags[512];
private Z80Flags[] Ptable = new Z80Flags[512];
private Z80Flags[] Stable = new Z80Flags[512];
private Z80Flags[] Ztable = new Z80Flags[512];
// Machine accessors
//
private IMemory memory;
private IDevice device;
private Clock clock;
// Main registers
//
private byte A;
private byte F;
private byte R;
private byte IFF1;
private byte IFF2;
private IRegister16 BC = Register16Factory.Create();
private IRegister16 DE = Register16Factory.Create();
private IRegister16 HL = Register16Factory.Create();
private IRegister16 IX = Register16Factory.Create();
private IRegister16 IY = Register16Factory.Create();
private IRegister16 SP = Register16Factory.Create();
private IRegister16 PC = Register16Factory.Create();
// Alternate registers
//
private IRegister16 AF_ = Register16Factory.Create();
private IRegister16 BC_ = Register16Factory.Create();
private IRegister16 DE_ = Register16Factory.Create();
private IRegister16 HL_ = Register16Factory.Create();
#endregion
#region ICpu Members
public void Initialise(IMemory memory, IDevice device, Clock clock)
{
this.memory = memory;
this.device = device;
this.clock = clock;
Reset();
}
public void Reset()
{
// TODO: Initial register settings.
}
public void Step()
{
// TODO: Single step.
}
public void Run()
{
// TODO: Run for a frame
}
public void MaskableInterrupt(byte value)
{
// TODO: INT
}
public void NonMaskableInterrupt(byte value)
{
// TODO: NMI
}
#endregion
#region Constructors
public Z80Cpu()
{
// Setup lookup tables
//
for(int f = 0; f < 256; f++)
{
Z80Flags p = Z80Flags.None;
Z80Flags z = Z80Flags.None;
Z80Flags s = Z80Flags.None;
int parity = 0;
for(int b=0; b < 8; b++)
{
if ((f & (1<<b)) == (1<<b))
{
parity++;
}
}
if ((parity & 1) == 1)
{
p = Z80Flags.PV;
}
if (f == 0)
{
z = Z80Flags.Zero;
}
if ((f & 0x80) == 0x80)
{
s = Z80Flags.Sign;
}
Ptable[f] = p;
Stable[f] = s;
Ztable[f] = z;
SZtable[f] =z|s;
PSZtable[f] = z|s|p;
Ptable[f+256] = Ptable[f]|Z80Flags.Carry;
Stable[f+256] = Stable[f]|Z80Flags.Carry;
Ztable[f+256] = Ztable[f]|Z80Flags.Carry;
SZtable[f+256] = SZtable[f]|Z80Flags.Carry;
PSZtable[f+256] = PSZtable[f]|Z80Flags.Carry;
}
}
#endregion
}
}
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