From 2b8d49726e448e22b5055da5ba4395d043030984 Mon Sep 17 00:00:00 2001 From: Ian C Date: Sun, 1 Jan 2012 14:21:26 +0000 Subject: Moved sources to help in compilation for other platforms and isolated phone projects. --- src/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs | 226 +++++++ .../Z80CpuBaseOpcodes.cs | 695 +++++++++++++++++++++ src/Noddybox.Emulation.EightBit/Binary.cs | 63 ++ src/Noddybox.Emulation.EightBit/ICpu.cs | 57 ++ src/Noddybox.Emulation.EightBit/IDevice.cs | 37 ++ src/Noddybox.Emulation.EightBit/IMemory.cs | 36 ++ src/Noddybox.Emulation.EightBit/Register16.cs | 88 +++ src/Noddybox.Emulation/Clock.cs | 112 ++++ 8 files changed, 1314 insertions(+) create mode 100644 src/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs create mode 100644 src/Noddybox.Emulation.EightBit.Z80/Z80CpuBaseOpcodes.cs create mode 100644 src/Noddybox.Emulation.EightBit/Binary.cs create mode 100644 src/Noddybox.Emulation.EightBit/ICpu.cs create mode 100644 src/Noddybox.Emulation.EightBit/IDevice.cs create mode 100644 src/Noddybox.Emulation.EightBit/IMemory.cs create mode 100644 src/Noddybox.Emulation.EightBit/Register16.cs create mode 100644 src/Noddybox.Emulation/Clock.cs (limited to 'src') diff --git a/src/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs b/src/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs new file mode 100644 index 0000000..5c40854 --- /dev/null +++ b/src/Noddybox.Emulation.EightBit.Z80/Z80Cpu.cs @@ -0,0 +1,226 @@ +// +// Copyright (c) 2012 Ian Cowburn +// +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 +{ + /// + /// Provides an implementation of a Zilog Z80 processor. + /// + 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]; + private Z80Flags[] H35table = new Z80Flags[256]; + + // Machine accessors + // + private IMemory memory; + private IDevice device; + private Clock clock; + + // Main registers + // + private byte A; + private Z80Flags F; + private Register16 BC = new Register16(0); + private Register16 DE = new Register16(0); + private Register16 HL = new Register16(0); + private Register16 IX = new Register16(0); + private Register16 IY = new Register16(0); + private ushort SP; + private ushort PC; + + // Alternate registers + // + private Register16 AF_ = new Register16(0); + private Register16 BC_ = new Register16(0); + private Register16 DE_ = new Register16(0); + private Register16 HL_ = new Register16(0); + + // Auxilliary registers and flags + // + private byte I; + private byte R; + private bool IFF1; + private bool IFF2; + private int IM; + private bool HALT; + + #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() + { + PC = 0; + A = 0xff; + F = (Z80Flags)0xff; + + BC.reg = 0xffff; + DE.reg = 0xffff; + HL.reg = 0xffff; + AF_.reg = 0xffff; + BC_.reg = 0xffff; + DE_.reg = 0xffff; + HL_.reg = 0xffff; + + IX.reg = 0xffff; + IY.reg = 0xffff; + + SP = 0xffff; + + IFF1 = false; + IFF2 = false; + IM = 0; + I = 0; + R = 0; + HALT = false; + } + + public void Step() + { + // TODO: Single step. + } + + public void Run() + { + while(!clock.FrameDone) + { + Step(); + } + } + + public void MaskableInterrupt(byte value) + { + clock.Add(2); + + // TODO: INT + } + + public void NonMaskableInterrupt(byte value) + { + clock.Add(2); + + // TODO: NMI + } + + #endregion + + #region Constructors + + public Z80Cpu() + { + // Verify runtime + // + Register16.Verify(); + + // Setup lookup tables + // + for(int f = 0; f < 256; f++) + { + Z80Flags p = Z80Flags.None; + Z80Flags z = Z80Flags.None; + Z80Flags s = Z80Flags.None; + Z80Flags h3 = Z80Flags.None; + Z80Flags h5 = Z80Flags.None; + + int parity = 0; + + for(int b=0; b < 8; b++) + { + if ((f & (1< + /// Set a flag in the status register. + /// + /// The flag. + private void SetFlag(Z80Flags flag) + { + F |= flag; + } + + /// + /// Clear a flag in the status register. + /// + /// The flag. + private void ClearFlag(Z80Flags flag) + { + F &= ~flag; + } + + #endregion + + #region Stack commands + + /// + /// Push a value on the stack. + /// + /// The value. + private void PUSH(ushort val) + { + memory.Write(--SP, (byte)(val & 0xff)); + memory.Write(--SP, (byte)(Binary.ShiftRight(val, 8) & 0xff)); + } + + /// + /// Pop a value from the stack. + /// + /// + private ushort POP() + { + SP = (ushort)((SP + 2) & 0xffff); + return (ushort)(memory.Read((ushort)(SP-2)) | + (memory.Read((ushort)(SP - 1)) >> 8)); + } + + #endregion + + #region ALU arithmetic and comparison + + /// + /// Add an 8-bit value to the accumulator without carry. + /// + /// The vakue. + private void Add8(byte b) + { + int w = A + b; + + F = SZtable[w] | H35table[w & 0xff]; + + if (((A ^ w ^ b) & (int)Z80Flags.HalfCarry) == (int)Z80Flags.HalfCarry) + { + F |= Z80Flags.HalfCarry; + } + + if (((b ^ A) & (b ^ w) & 0x80) > 0) + { + F |= Z80Flags.PV; + } + + A = (byte)(w & 0xff); + } + + /// + /// Add an 8-bit value to the accumulator with carry. + /// + /// The vakue. + private void Adc8(byte b) + { + int w = A + b + (int)(F & Z80Flags.Carry); + + F = SZtable[w] | H35table[w & 0xff]; + + if (((A ^ w ^ b) & (int)Z80Flags.HalfCarry) == (int)Z80Flags.HalfCarry) + { + F |= Z80Flags.HalfCarry; + } + + if (((b ^ A) & (b ^ w) & 0x80) > 0) + { + F |= Z80Flags.PV; + } + + A = (byte)(w & 0xff); + } + + /// + /// Subtract an 8-bit value from the accumulator without carry. + /// + /// The vakue. + private void Sub8(byte b) + { + int w = A - b; + + if (w < 0) + { + w += 0x200; + } + + F = SZtable[w] | H35table[w & 0xff] | Z80Flags.Neg; + + if (((A ^ w ^ b) & (int)Z80Flags.HalfCarry) == (int)Z80Flags.HalfCarry) + { + F |= Z80Flags.HalfCarry; + } + + if (((b ^ A) & (b ^ w) & 0x80) > 0) + { + F |= Z80Flags.PV; + } + + A = (byte)(w & 0xff); + } + + /// + /// Compare an 8-bit value with the accumulator. + /// + /// The vakue. + private void Cmp8(byte b) + { + int w = A - b; + + if (w < 0) + { + w += 0x200; + } + + F = SZtable[w] | H35table[w & 0xff] | Z80Flags.Neg; + + if (((A ^ w ^ b) & (int)Z80Flags.HalfCarry) == (int)Z80Flags.HalfCarry) + { + F |= Z80Flags.HalfCarry; + } + + if (((b ^ A) & (b ^ w) & 0x80) > 0) + { + F |= Z80Flags.PV; + } + } + + /// + /// Subtract an 8-bit value from the accumulator with carry. + /// + /// The vakue. + private void Sbc8(byte b) + { + int w = A - b - (int)(F & Z80Flags.Carry); + + if (w < 0) + { + w += 0x200; + } + + F = SZtable[w] | H35table[w & 0xff] | Z80Flags.Neg; + + if (((A ^ w ^ b) & (int)Z80Flags.HalfCarry) == (int)Z80Flags.HalfCarry) + { + F |= Z80Flags.HalfCarry; + } + + if (((b ^ A) & (b ^ w) & 0x80) > 0) + { + F |= Z80Flags.PV; + } + + A = (byte)(w & 0xff); + } + + /// + /// Add a 16-bit value to a register without carry. + /// + /// The vakue. + private void Add16(ref ushort reg, ushort b) + { + int w = reg + b; + + F &= Z80Flags.Sign | Z80Flags.Zero | Z80Flags.PV; + + if (w > 0xffff) + { + F |= Z80Flags.Carry; + } + + if ((reg ^ w ^ b) == 0x1000) + { + F |= Z80Flags.HalfCarry; + } + + reg = (ushort)(w & 0xffff); + + F |= H35table[reg >> 8]; + } + + /// + /// Add a 16-bit value to a register with carry. + /// + /// The vakue. + private void Adc16(ref ushort reg, ushort b) + { + int w = reg + b + (int)(F & Z80Flags.Carry); + + F = Z80Flags.None; + + if ((w & 0xffff) == 0) + { + F |= Z80Flags.Zero; + } + + if ((w & 0x8000) == 0x8000) + { + F |= Z80Flags.Sign; + } + + if (w > 0xffff) + { + F |= Z80Flags.Carry; + } + + if (((b ^ reg ^ 0x8000) & ((reg ^ w) & 0x8000)) == 0x8000) + { + F |= Z80Flags.PV; + } + + if ((reg ^ w ^ b) == 0x1000) + { + F |= Z80Flags.HalfCarry; + } + + reg = (ushort)(w & 0xffff); + + F |= H35table[reg >> 8]; + } + + + /// + /// Subtract a 16-bit value from a register with carry. + /// + /// The vakue. + private void Sbc16(ref ushort reg, ushort b) + { + int w = reg - b - (int)(F & Z80Flags.Carry); + + F = Z80Flags.Neg; + + if (w < 0) + { + w += 0x10000; + F |= Z80Flags.Carry; + } + + if ((w & 0xffff) == 0) + { + F |= Z80Flags.Zero; + } + + if ((w & 0x8000) == 0x8000) + { + F |= Z80Flags.Sign; + } + + if (((b ^ reg) & ((reg ^ w) & 0x8000)) == 0x8000) + { + F |= Z80Flags.PV; + } + + if ((reg ^ w ^ b) == 0x1000) + { + F |= Z80Flags.HalfCarry; + } + + reg = (ushort)(w & 0xffff); + + F |= H35table[reg >> 8]; + } + + /// + /// Increment an 8-bit register. + /// + /// The register to increment. + void Inc8(ref byte reg) + { + reg++; + + F = Z80Flags.Carry; + + if (reg == 0x80) + { + F |= Z80Flags.PV; + } + + if ((reg & 0x0f) == 0x00) + { + F |= Z80Flags.HalfCarry; + } + } + + /// + /// Decrement an 8-bit register. + /// + /// The register to decrement. + void Dec8(ref byte reg) + { + reg--; + + F = Z80Flags.Carry | Z80Flags.Neg; + + if (reg == 0x7f) + { + F |= Z80Flags.PV; + } + + if ((reg & 0x0f) == 0x0f) + { + F |= Z80Flags.HalfCarry; + } + } + + #endregion + + #region ALU rotate and shift operations + + /// + /// Do RRCA. + /// + private void RRCA() + { + F &= Z80Flags.Sign | Z80Flags.Zero | Z80Flags.PV; + F |= (Z80Flags)(A & 1); + A = (byte)(Binary.ShiftRight(A, 1) | Binary.ShiftLeft(A, 7)); + F |= H35table[A]; + } + + /// + /// Do RRA. + /// + private void RRA() + { + byte carry = (byte)(F & Z80Flags.Carry); + F &= Z80Flags.Sign | Z80Flags.Zero | Z80Flags.PV; + F |= (Z80Flags)(A & 1); + A = (byte)(Binary.ShiftRight(A, 1) | Binary.ShiftLeft(carry, 7)); + F |= H35table[A]; + } + + /// + /// Do RRC. + /// + /// The register to operate on. + private void RRC(ref byte reg) + { + F = (Z80Flags)(reg & (int)Z80Flags.Carry); + reg = (byte)(Binary.ShiftRight(reg, 1) | Binary.ShiftLeft(reg, 7)); + F |= PSZtable[reg] | H35table[reg]; + } + + /// + /// Do RR. + /// + /// The register to operate on. + private void RR(ref byte reg) + { + byte carry = (byte)(F & Z80Flags.Carry); + F = (Z80Flags)(reg & (int)Z80Flags.Carry); + reg = (byte)(Binary.ShiftRight(reg, 1) | Binary.ShiftLeft(carry, 7)); + F |= PSZtable[reg] | H35table[reg]; + } + + /// + /// Do RLCA. + /// + private void RLCA() + { + F = (F & Z80Flags.PV | Z80Flags.Sign | Z80Flags.Zero) + | (Z80Flags)Binary.ShiftRight(A, 7); + + A = (byte)(Binary.ShiftLeft(A, 1) | Binary.ShiftRight(A, 7)); + + F |= H35table[A]; + } + + /// + /// Do RLA. + /// + private void RLA() + { + byte carry = (byte)(F & Z80Flags.Carry); + F = (F & Z80Flags.PV | Z80Flags.Sign | Z80Flags.Zero) + | (Z80Flags)Binary.ShiftRight(A, 7); + A = (byte)(Binary.ShiftRight(A, 1) | carry); + F |= H35table[A]; + } + + /// + /// Do RLC. + /// + /// The register to operate on. + private void RLC(ref byte reg) + { + byte carry = Binary.ShiftRight(reg, 7); + reg = (byte)(Binary.ShiftLeft(reg, 1) | carry); + F = PSZtable[reg] | (Z80Flags)carry | H35table[reg]; + } + + /// + /// Do RL. + /// + /// The register to operate on. + private void RL(ref byte reg) + { + byte carry = Binary.ShiftRight(reg, 7); + reg = (byte)(Binary.ShiftLeft(reg, 1) | (int)(F & Z80Flags.Carry)); + F = PSZtable[reg] | (Z80Flags)carry | H35table[reg]; + } + + /// + /// Do SRL. + /// + /// The register to operate on. + private void SRL(ref byte reg) + { + byte carry = (byte)(reg & 1); + reg = Binary.ShiftLeft(reg, 1); + F = PSZtable[reg] | (Z80Flags)carry | H35table[reg]; + } + + /// + /// Do SRA. + /// + /// The register to operate on. + private void SRA(ref byte reg) + { + byte carry = (byte)(reg & 1); + reg = (byte)(Binary.ShiftLeft(reg, 1) | (reg & 0x80)); + F = PSZtable[reg] | (Z80Flags)carry | H35table[reg]; + } + + /// + /// Do SLL. + /// + /// The register to operate on. + private void SLL(ref byte reg) + { + byte carry = Binary.ShiftRight(reg, 7); + reg = (byte)(Binary.ShiftRight(reg, 1) | 0x01); + F = PSZtable[reg] | (Z80Flags)carry | H35table[reg]; + } + + /// + /// Do SLA. + /// + /// The register to operate on. + private void SLA(ref byte reg) + { + byte carry = Binary.ShiftRight(reg, 7); + reg = Binary.ShiftRight(reg, 1); + F = PSZtable[reg] | (Z80Flags)carry | H35table[reg]; + } + + #endregion + + #region ALU boolean operations + + /// + /// AND a value with the accumulator. + /// + /// The value. + void AND(byte val) + { + A &= val; + F = PSZtable[A] | Z80Flags.HalfCarry | H35table[A]; + } + + /// + /// OR a value with the accumulator. + /// + /// The value. + void OR(byte val) + { + A |= val; + F = PSZtable[A] | Z80Flags.HalfCarry | H35table[A]; + } + + /// + /// XOR a value with the accumulator. + /// + /// The value. + void XOR(byte val) + { + A ^= val; + F = PSZtable[A] | Z80Flags.HalfCarry | H35table[A]; + } + + /// + /// Perform the BIT operation. + /// + /// The register to operate on. + /// The bit to test. + void BIT(ref byte reg, int bit) + { + F &= Z80Flags.Carry; + F |= Z80Flags.HalfCarry; + + if ((reg & (1 << bit)) != 0) + { + if (bit == 7 && (reg & (int)Z80Flags.Sign) != 0) + { + F |= Z80Flags.Sign; + } + + if (bit == 5 && (reg & (int)Z80Flags.Hidden5) != 0) + { + F |= Z80Flags.Hidden5; + } + + if (bit == 3 && (reg & (int)Z80Flags.Hidden3) != 0) + { + F |= Z80Flags.Hidden3; + } + } + else + { + F |= Z80Flags.Zero | Z80Flags.PV; + } + } + + /// + /// Perform the bit set operation. + /// + /// The register to operate on. + /// The bit to test. + void BIT_SET(ref byte reg, int bit) + { + reg |= (byte)(1 << bit); + } + + /// + /// Perform the bit clear operation. + /// + /// The register to operate on. + /// The bit to test. + void BIT_RES(ref byte reg, int bit) + { + reg &= (byte)~(1 << bit); + } + + #endregion + + #region Jump operations + + /// + /// The call operation. + /// + private void CALL() + { + PUSH((ushort)(PC + 2)); + PC = (ushort)(memory.Read(PC) | memory.Read((ushort)(PC+1)) >> 8); + } + + /// + /// The jump operation. + /// + private void JP() + { + PC = (ushort)(memory.Read(PC) | memory.Read((ushort)(PC+1)) >> 8); + } + + /// + /// The jump relative operation. + /// + private void JR() + { + PC = (ushort)(PC + (sbyte)memory.Read(PC) + 1); + } + + /// + /// Jump relative if the passed condition flag ANDed with the flag + /// register equals the passed check value. + /// + /// The condition flag. + /// The check value. + private void JR_COND(Z80Flags cond, Z80Flags val) + { + if ((F & cond) == val) + { + clock.Add(12); + JR(); + } + else + { + clock.Add(7); + PC++; + } + } + + /// + /// Jump if the passed condition flag ANDed with the flag + /// register equals the passed check value. + /// + /// The condition flag. + /// The check value. + private void JP_COND(Z80Flags cond, Z80Flags val) + { + clock.Add(10); + + if ((F & cond) == val) + { + JP(); + } + else + { + PC+=2; + } + } + + /// + /// Call if the passed condition flag ANDed with the flag + /// register equals the passed check value. + /// + /// The condition flag. + /// The check value. + private void CALL_COND(Z80Flags cond, Z80Flags val) + { + if ((F & cond) == val) + { + clock.Add(17); + CALL(); + } + else + { + clock.Add(10); + PC+=2; + } + } + + /// + /// Return if the passed condition flag ANDed with the flag + /// register equals the passed check value. + /// + /// The condition flag. + /// The check value. + private void RET_COND(Z80Flags cond, Z80Flags val) + { + if ((F & cond) == val) + { + clock.Add(11); + PC = POP(); + } + else + { + clock.Add(5); + } + } + + /// + /// Reset the PC to an address + /// register equals the passed check value. + /// + /// The address. + private void RST(ushort addr) + { + clock.Add(11); + PUSH(PC); + PC = addr; + } + + #endregion + } +} diff --git a/src/Noddybox.Emulation.EightBit/Binary.cs b/src/Noddybox.Emulation.EightBit/Binary.cs new file mode 100644 index 0000000..0b1928b --- /dev/null +++ b/src/Noddybox.Emulation.EightBit/Binary.cs @@ -0,0 +1,63 @@ +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 +{ + /// + /// Provides helpers for shifting smaller values around without casts all over the shop. + /// + public static class Binary + { + /// + /// Shift 8-bits to the left. + /// + /// The byte. + /// How many bits to shift. + /// The shifted value. + public static byte ShiftLeft(byte b, int shift) + { + return (byte)((b << shift) & 0xff); + } + + /// + /// Shift 8-bits to the right. + /// + /// The byte. + /// How many bits to shift. + /// The shifted value. + public static byte ShiftRight(byte b, int shift) + { + return (byte)((b >> shift) & 0xff); + } + + /// + /// Shift 16-bits to the left. + /// + /// The word. + /// How many bits to shift. + /// The shifted value. + public static ushort ShiftLeft(ushort w, int shift) + { + return (ushort)((w << shift) & 0xffff); + } + + /// + /// Shift 16-bits to the right. + /// + /// The word. + /// How many bits to shift. + /// The shifted value. + public static ushort ShiftRight(ushort w, int shift) + { + return (ushort)((w >> shift) & 0xffff); + } + } +} diff --git a/src/Noddybox.Emulation.EightBit/ICpu.cs b/src/Noddybox.Emulation.EightBit/ICpu.cs new file mode 100644 index 0000000..dc2f811 --- /dev/null +++ b/src/Noddybox.Emulation.EightBit/ICpu.cs @@ -0,0 +1,57 @@ +// +// Copyright (c) 2012 Ian Cowburn +// +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 +{ + /// + /// Defines an 8-bit CPU. + /// + public interface ICpu + { + /// + /// Initialise the CPU to give it access to memory and devices. + /// + /// The memory to access. + /// The devices to access. + /// The clock to use. + void Initialise(IMemory memory, IDevice device, Clock clock); + + /// + /// Resets the CPU to its initial state. + /// + void Reset(); + + /// + /// Runs the next instruction. + /// + void Step(); + + /// + /// Runs the CPU until the next frame flyback. + /// + void Run(); + + /// + /// Generates a maskable interrupt to the CPU. + /// + /// Optional value from an interrupting device. May be ignored depending on the CPU type. + void MaskableInterrupt(byte value); + + /// + /// Generates a non-maskable interrupt to the CPU. + /// + /// Optional value from an interrupting device. May be ignored depending on the CPU type. + void NonMaskableInterrupt(byte value); + } +} diff --git a/src/Noddybox.Emulation.EightBit/IDevice.cs b/src/Noddybox.Emulation.EightBit/IDevice.cs new file mode 100644 index 0000000..b8d234a --- /dev/null +++ b/src/Noddybox.Emulation.EightBit/IDevice.cs @@ -0,0 +1,37 @@ +// +// Copyright (c) 2012 Ian Cowburn +// +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 +{ + /// + /// Provides an interface for devices for 8-bit processers which used special commands to access + /// devices rather than using memory-mapped IO, for example the Z80. + /// + public interface IDevice + { + /// + /// Read from a device. + /// + /// The address of the device. + /// The byte returned from the device. + byte Read(ushort device); + + /// + /// Write to a device. + /// + /// The address of the device. + /// The value to write to the device. + void Write(ushort device, byte value); + } +} diff --git a/src/Noddybox.Emulation.EightBit/IMemory.cs b/src/Noddybox.Emulation.EightBit/IMemory.cs new file mode 100644 index 0000000..2aa63d9 --- /dev/null +++ b/src/Noddybox.Emulation.EightBit/IMemory.cs @@ -0,0 +1,36 @@ +// +// Copyright (c) 2012 Ian Cowburn +// +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 +{ + /// + /// Defines an interface for memory. + /// + public interface IMemory + { + /// + /// Reads a byte at a given address. + /// + /// The address to read. + /// The value at that address. + byte Read(ushort address); + + /// + /// Writes a byte at a given address. + /// + /// The address to write to. + /// The value to write. + void Write(ushort address, byte value); + } +} diff --git a/src/Noddybox.Emulation.EightBit/Register16.cs b/src/Noddybox.Emulation.EightBit/Register16.cs new file mode 100644 index 0000000..06c9c01 --- /dev/null +++ b/src/Noddybox.Emulation.EightBit/Register16.cs @@ -0,0 +1,88 @@ +// +// Copyright (c) 2012 Ian Cowburn +// +using System; +using System.Runtime.InteropServices; + +namespace Noddybox.Emulation.EightBit +{ + /// + /// Provides a common 8-bit register pattern, which is two 8-bit registers rolled into one. + /// While this could be done at runtime using this + /// method was chosen for speed reasons; interfaces cannot define fields, which is sensible + /// enoough, but accessing fields directly would allow ref variables to be used with this type's + /// fields. + /// + [StructLayout(LayoutKind.Explicit)] + public struct Register16 + { +#if TARGET_IS_BIGENDIAN + + /// + /// The 16-bit register. + /// + [FieldOffset(0)] + public ushort reg; + + /// + /// The high 8-bits of the register. + /// + [FieldOffset(0)] + public byte high; + + /// + /// The low 8-bits of the register. + /// + [FieldOffset(1)] + public byte low; + +#else + + /// + /// The 16-bit register. + /// + [FieldOffset(0)] + public ushort reg; + + /// + /// The low 8-bits of the register. + /// + [FieldOffset(0)] + public byte low; + + /// + /// The high 8-bits of the register. + /// + [FieldOffset(1)] + public byte high; + +#endif + + /// + /// Public constructor. This is provided to stop the compiler complaining when you use the struct as it + /// doesn't realise that setting will also set and . + /// + /// The 16-bit value to assign. + public Register16(ushort val) + { + high = 0; + low = 0; + reg = val; + } + + /// + /// Used to verify the compile-time setting at runtime. + /// + public static void Verify() + { + Register16 r = new Register16(0); + + r.reg = 0x1234; + + if (r.low != 0x24 || r.high != 0x12) + { + throw new Exception("Compile time endian setting incorrect"); + } + } + } +} diff --git a/src/Noddybox.Emulation/Clock.cs b/src/Noddybox.Emulation/Clock.cs new file mode 100644 index 0000000..0b733cb --- /dev/null +++ b/src/Noddybox.Emulation/Clock.cs @@ -0,0 +1,112 @@ +// +// Copyright (c) 2012 Ian Cowburn +// +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 +{ + /// + /// Provides a basic clock implementation that is geared towards the VBL. + /// + public class Clock + { + #region Private fields + + private uint perSecond; + private uint perFrame; + private uint perLine; + private uint frameCount; + + #endregion + + #region Public properties + + /// + /// Returns true if the frame has finished. + /// + public bool FrameDone + { + get + { + return frameCount > perFrame; + } + } + + /// + /// Returns the current raster line. + /// + public uint RasterLine + { + get + { + return frameCount / perLine; + } + } + + #endregion + + #region Public members + + /// + /// Starts a new frame. + /// + public void StartFrame() + { + if (FrameDone) + { + frameCount -= perFrame; + } + } + + /// + /// Adds a number of ticks to the clock. + /// + /// The ticks to add. + public void Add(uint ticks) + { + frameCount += ticks; + } + + #endregion + + #region Constructors + + /// + /// Defines a clock. + /// + /// The number of ticks per second. + /// The number of frames per second. + public Clock(uint ticksPerSecond, uint framesPerSecond) + { + this.perSecond = ticksPerSecond; + this.perFrame = ticksPerSecond / framesPerSecond; + this.perLine = 1; + this.frameCount = 0; + } + + /// + /// Defines a clock. + /// + /// The number of ticks per second. + /// The number of frames per second. + /// The number of clock ticks per raster line. + public Clock(uint ticksPerSecond, uint framesPerSecond, uint ticksPerLine) + { + this.perSecond = ticksPerSecond; + this.perFrame = ticksPerSecond / framesPerSecond; + this.perLine = ticksPerLine; + this.frameCount = 0; + } + + #endregion + } +} -- cgit v1.2.3