diff options
| author | Ian C <ianc@noddybox.co.uk> | 2011-12-28 00:11:12 +0000 |
|---|---|---|
| committer | Ian C <ianc@noddybox.co.uk> | 2011-12-28 00:11:12 +0000 |
| commit | 2e3102879b2d3059f4ce0efc1a0ecd4bc3142a99 (patch) | |
| tree | 08050e094fc71a911195d72aeeca080e0361c48b /Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs | |
| parent | d21b1c0d0a533b70c3ed13d888ff7b6a8a6babd8 (diff) | |
Added some more base classes and started on the Z80 implementation.
Diffstat (limited to 'Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs')
| -rw-r--r-- | Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs b/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs new file mode 100644 index 0000000..d967bb9 --- /dev/null +++ b/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs @@ -0,0 +1,167 @@ +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
+ }
+}
|