summaryrefslogtreecommitdiff
path: root/Emulator/Chip/Q1Cpu.cs
diff options
context:
space:
mode:
Diffstat (limited to 'Emulator/Chip/Q1Cpu.cs')
-rw-r--r--Emulator/Chip/Q1Cpu.cs167
1 files changed, 0 insertions, 167 deletions
diff --git a/Emulator/Chip/Q1Cpu.cs b/Emulator/Chip/Q1Cpu.cs
deleted file mode 100644
index 81f9908..0000000
--- a/Emulator/Chip/Q1Cpu.cs
+++ /dev/null
@@ -1,167 +0,0 @@
-namespace Q1.Emulator.Chip;
-
-using System;
-using Assembler;
-
-public partial class Q1Cpu
-{
- public Random Random;
-
- public u16 AX = 0; // Accumulator register
- public u16 DX = 0; // Data register
- public u16 LX = 0; // Logical register
-
- public u16 SP { get; set; } // Stack pointer
- public u16 PC { get; set; } // Program counter
-
- public u16[] V { get; set; } // Variable registers (64 total)
- public u16 Cycles { get; set; } // Number of cycles
-
- public Bus Bus { get; set; }
- public bool AbortRequested = false;
-
- public Q1Cpu()
- {
- this.LoadInstructionLookup();
- }
-
- public void Reset()
- {
- this.AbortRequested = false;
-
- this.V = new u16[64];
-
- this.SP = Q1Layout.StackStart;
- this.PushStack(0xFFFF);
-
- this.PC = Q1Layout.ProgramStart;
- }
-
- public void Clock()
- {
- var pc = this.PC;
- if (pc == 0xFFFF)
- {
- this.AbortRequested = true;
- return;
- }
-
- u16 instruction = this.FetchInstruction(out u8 op, out u8 m1, out u8 m2, out _);
- // if (instruction != 0x0101)
- // Console.WriteLine($"CPU.Clock: {pc:X4} | {Disassembler.ParseInstruction(instruction)}");
-
- bool ex = m2 > 0;
- switch (m1, ex)
- {
- case (0x00, false):
- this.InstructionLookup[op].Item1(); // Implicit
- break;
- case (> 0x00, false):
- this.InstructionLookup[op].Item2(m1); // Simple addressing mode
- break;
- case (0x00, true):
- this.InstructionLookup[op].Item3(); // Extended implicit
- break;
- case (> 0x00, true):
- this.InstructionLookup[op].Item4(m1, m2); // Extended addressing mode
- break;
- }
-
- this.Cycles++;
- }
- public u16 FetchInstruction(out u8 op, out u8 m1, out u8 m2, out u8 length)
- {
- u16 instruction = this.Bus.ReadWord(this.PC);
- this.PC += 2;
-
- op = (u8) ((instruction >> 8) & 0xFF); // 256 opcodes
- m1 = (u8) ((instruction >> 4) & 0x0F); // 16 modes
- m2 = (u8) (instruction & 0x0F); // 16 modes
-
- length = (u8) (this.AddressingModeLength(m1) + this.AddressingModeLength(m2));
- return instruction;
- }
-
- private void PushStack(u16 value)
- {
- if (this.SP + 2 >= Q1Layout.StackStart + Q1Layout.StackLength)
- throw new InvalidOperationException("Stack overflow");
-
- this.Bus.WriteWord(this.SP, value);
- this.SP += 2;
- }
-
- private u16 PopStack()
- {
- if (this.SP - 2 < Q1Layout.StackStart)
- throw new InvalidOperationException("Stack underflow");
-
- this.SP -= 2;
- return this.Bus.ReadWord(this.SP);
- }
-
- private u16 FetchRegister(u8 regIndex)
- {
- return regIndex switch
- {
- <= 0x3F => this.V[regIndex],
-
- 0x40 => this.AX,
- 0x41 => (u16) (this.AX >> 8), // High byte of AX
- 0x42 => (u16) (this.AX & 0xFF), // Low byte of AX
-
- 0x43 => this.DX,
- 0x44 => (u16) (this.DX >> 8), // High byte of DX
- 0x45 => (u16) (this.DX & 0xFF), // Low byte of DX
-
- 0x46 => this.LX,
- 0x50 => this.PC,
- 0x51 => this.SP,
-
- _ => throw new InvalidOperationException($"Unknown register index: {regIndex:X2}"),
- };
- }
-
- private void StoreRegister(u8 regIndex, u16 value)
- {
- switch (regIndex)
- {
- case <= 0x3F:
- this.V[regIndex] = value;
- break;
-
- case 0x40:
- this.AX = value;
- break;
- case 0x41:
- this.AX = (u16) ((this.AX & 0x00FF) | (value << 8));
- break; // Set high byte
- case 0x42:
- this.AX = (u16) ((this.AX & 0xFF00) | (value & 0x00FF));
- break; // Set low byte
-
- case 0x43:
- this.DX = value;
- break;
- case 0x44:
- this.DX = (u16) ((this.DX & 0x00FF) | (value << 8));
- break; // Set high byte
- case 0x45:
- this.DX = (u16) ((this.DX & 0xFF00) | (value & 0x00FF));
- break; // Set low byte
-
- case 0x46:
- this.LX = value;
- break;
- case 0x50:
- this.PC = value;
- break;
- case 0x51:
- this.SP = value;
- break;
-
- default:
- throw new InvalidOperationException($"Unknown register index: {regIndex:X2}");
- }
- }
-} \ No newline at end of file