6502/EightBitNet
1
0
Fork 0
mirror of https://github.com/MoleskiCoder/EightBitNet.git synced 2026-04-21 12:16:55 +00:00
Code Issues Projects Releases Wiki Activity

Fix up some oddities in the EightBit library

Browse Source
This commit is contained in:
Adrian Conlon
2025-10-06 13:44:31 +01:00
parent 3ca62c908c
commit ceacac4741
30 changed files with 9775 additions and 486 deletions
Download Patch File Download Diff File Expand all files Collapse all files
MC6809/MC6809.Test/Board.cs
+93 -91
View File
@@ -2,17 +2,18 @@
// Copyright (c) Adrian Conlon. All rights reserved.
// </copyright>
namespace EightBit
namespace MC6809.Test
{
using EightBit;
using System;
public sealed class Board : Bus
{
private readonly Configuration configuration;
private readonly Ram ram = new Ram(0x8000); // 0000 - 7FFF, 32K RAM
private readonly UnusedMemory unused2000 = new UnusedMemory(0x2000, 0xff); // 8000 - 9FFF, 8K unused
private readonly Ram io = new Ram(0x2000); // A000 - BFFF, 8K serial interface, minimally decoded
private readonly Rom rom = new Rom(0x4000); // C000 - FFFF, 16K ROM
private readonly Ram ram = new(0x8000); // 0000 - 7FFF, 32K RAM
private readonly UnusedMemory unused2000 = new(0x2000, 0xff); // 8000 - 9FFF, 8K unused
private readonly Ram io = new(0x2000); // A000 - BFFF, 8K serial interface, minimally decoded
private readonly Rom rom = new(0x4000); // C000 - FFFF, 16K ROM
private readonly Disassembler disassembler;
private readonly Profiler profiler;
@@ -27,9 +28,9 @@ namespace EightBit
public Board(Configuration configuration)
{
this.configuration = configuration;
this.CPU = new MC6809(this);
this.disassembler = new Disassembler(this, this.CPU);
this.profiler = new Profiler(this, this.CPU, this.disassembler);
CPU = new MC6809(this);
disassembler = new Disassembler(this, CPU);
profiler = new Profiler(this, CPU, disassembler);
}
public MC6809 CPU { get; }
@@ -40,20 +41,20 @@ namespace EightBit
{
if (absolute < 0x8000)
{
return new MemoryMapping(this.ram, 0x0000, Mask.Sixteen, AccessLevel.ReadWrite);
return new MemoryMapping(ram, 0x0000, Mask.Sixteen, AccessLevel.ReadWrite);
}
if (absolute < 0xa000)
{
return new MemoryMapping(this.unused2000, 0x8000, Mask.Sixteen, AccessLevel.ReadOnly);
return new MemoryMapping(unused2000, 0x8000, Mask.Sixteen, AccessLevel.ReadOnly);
}
if (absolute < 0xc000)
{
return new MemoryMapping(this.io, 0xa000, Mask.Sixteen, AccessLevel.ReadWrite);
return new MemoryMapping(io, 0xa000, Mask.Sixteen, AccessLevel.ReadWrite);
}
return new MemoryMapping(this.rom, 0xc000, Mask.Sixteen, AccessLevel.ReadOnly);
return new MemoryMapping(rom, 0xc000, Mask.Sixteen, AccessLevel.ReadOnly);
}
public override void RaisePOWER()
@@ -61,166 +62,167 @@ namespace EightBit
base.RaisePOWER();
// Get the CPU ready for action
this.CPU.RaisePOWER();
this.CPU.LowerRESET();
this.CPU.RaiseINT();
this.CPU.RaiseNMI();
this.CPU.RaiseFIRQ();
this.CPU.RaiseHALT();
CPU.RaisePOWER();
CPU.LowerRESET();
CPU.RaiseINT();
CPU.RaiseNMI();
CPU.RaiseFIRQ();
CPU.RaiseHALT();
// Get the ACIA ready for action
this.Address.Word = 0b1010000000000000;
this.Data = (byte)(MC6850.ControlRegister.CR0 | MC6850.ControlRegister.CR1); // Master reset
this.ACIA.CTS.Lower();
this.ACIA.RW.Lower();
this.UpdateAciaPins();
this.ACIA.RaisePOWER();
this.AccessAcia();
Address.Word = 0b1010000000000000;
Data = (byte)(MC6850.ControlRegister.CR0 | MC6850.ControlRegister.CR1); // Master reset
ACIA.CTS.Lower();
ACIA.RW.Lower();
UpdateAciaPins();
ACIA.RaisePOWER();
AccessAcia();
}
public override void LowerPOWER()
{
////this.profiler.Generate();
this.ACIA.LowerPOWER();
this.CPU.LowerPOWER();
ACIA.LowerPOWER();
CPU.LowerPOWER();
base.LowerPOWER();
}
public override void Initialize()
{
System.Console.TreatControlCAsInput = true;
Console.TreatControlCAsInput = true;
// Load our BASIC interpreter
var directory = this.configuration.RomDirectory + "\\";
this.LoadHexFile(directory + "ExBasROM.hex");
var directory = configuration.RomDirectory + "\\";
LoadHexFile(directory + "ExBasROM.hex");
// Catch a byte being transmitted
this.ACIA.Transmitting += this.ACIA_Transmitting;
ACIA.Transmitting += ACIA_Transmitting;
// Keyboard wiring, check for input once per frame
this.CPU.ExecutedInstruction += this.CPU_ExecutedInstruction;
CPU.ExecutedInstruction += CPU_ExecutedInstruction;
if (this.configuration.DebugMode)
// Marshal data from ACIA -> memory
this.ReadingByte += Board_ReadingByte;
// Marshal data from memory -> ACIA
this.WrittenByte += Board_WrittenByte;
if (configuration.DebugMode)
{
// MC6809 disassembly wiring
this.CPU.ExecutingInstruction += this.CPU_ExecutingInstruction;
this.CPU.ExecutedInstruction += this.CPU_ExecutedInstruction_Debug;
CPU.ExecutingInstruction += CPU_ExecutingInstruction;
CPU.ExecutedInstruction += CPU_ExecutedInstruction_Debug;
}
if (this.configuration.TerminatesEarly)
if (configuration.TerminatesEarly)
{
// Early termination condition for CPU timing code
this.CPU.ExecutedInstruction += this.CPU_ExecutedInstruction_Termination;
CPU.ExecutedInstruction += CPU_ExecutedInstruction_Termination;
}
////this.profiler.Enable();
////this.profiler.EmitLine += this.Profiler_EmitLine;
}
// Marshal data from ACIA -> memory
protected override void OnReadingByte()
private void Board_ReadingByte(object? sender, EventArgs e)
{
this.UpdateAciaPins();
this.ACIA.RW.Raise();
if (this.AccessAcia())
UpdateAciaPins();
ACIA.RW.Raise();
if (AccessAcia())
{
this.Poke(this.ACIA.DATA);
}
base.OnReadingByte();
}
// Marshal data from memory -> ACIA
protected override void OnWrittenByte()
{
base.OnWrittenByte();
this.UpdateAciaPins();
if (this.ACIA.Selected)
{
this.ACIA.RW.Lower();
this.AccessAcia();
Poke(ACIA.DATA);
}
}
private void Profiler_EmitLine(object sender, ProfileLineEventArgs e)
private void Board_WrittenByte(object? sender, EventArgs e)
{
UpdateAciaPins();
if (ACIA.Selected)
{
ACIA.RW.Lower();
AccessAcia();
}
}
private void Profiler_EmitLine(object? sender, ProfileLineEventArgs e)
{
var cycles = e.Cycles;
var disassembled = e.Source;
System.Console.Error.WriteLine(disassembled);
Console.Error.WriteLine(disassembled);
}
private void CPU_ExecutedInstruction_Termination(object sender, EventArgs e)
private void CPU_ExecutedInstruction_Termination(object? sender, EventArgs e)
{
this.totalCycleCount += (ulong)this.CPU.Cycles;
if (this.totalCycleCount > Configuration.TerminationCycles)
totalCycleCount += (ulong)CPU.Cycles;
if (totalCycleCount > Configuration.TerminationCycles)
{
this.LowerPOWER();
LowerPOWER();
}
}
private void CPU_ExecutedInstruction_Debug(object sender, EventArgs e)
private void CPU_ExecutedInstruction_Debug(object? sender, EventArgs e)
{
if (!this.ignoreDisassembly)
if (!ignoreDisassembly)
{
var disassembled = $"{this.disassembler.Trace(this.disassembleAt)}\t{this.ACIA.DumpStatus()}";
System.Console.Error.WriteLine(disassembled);
var disassembled = $"{disassembler.Trace(disassembleAt)}\t{ACIA.DumpStatus()}";
Console.Error.WriteLine(disassembled);
}
}
private void CPU_ExecutingInstruction(object sender, EventArgs e)
private void CPU_ExecutingInstruction(object? sender, EventArgs e)
{
this.disassembleAt = this.CPU.PC.Word;
this.ignoreDisassembly = this.disassembler.Ignore || this.disassembler.Pause;
disassembleAt = CPU.PC.Word;
ignoreDisassembly = disassembler.Ignore || disassembler.Pause;
}
private void CPU_ExecutedInstruction(object sender, EventArgs e)
private void CPU_ExecutedInstruction(object? sender, EventArgs e)
{
this.frameCycleCount -= this.CPU.Cycles;
if (this.frameCycleCount < 0)
frameCycleCount -= CPU.Cycles;
if (frameCycleCount < 0)
{
if (System.Console.KeyAvailable)
if (Console.KeyAvailable)
{
var key = System.Console.ReadKey(true);
var key = Console.ReadKey(true);
if (key.Key == ConsoleKey.F12)
{
this.LowerPOWER();
LowerPOWER();
}
this.ACIA.RDR = System.Convert.ToByte(key.KeyChar);
this.ACIA.MarkReceiveStarting();
ACIA.RDR = Convert.ToByte(key.KeyChar);
ACIA.MarkReceiveStarting();
}
this.frameCycleCount = (long)Configuration.FrameCycleInterval;
frameCycleCount = (long)Configuration.FrameCycleInterval;
}
}
private void ACIA_Transmitting(object sender, EventArgs e)
private void ACIA_Transmitting(object? sender, EventArgs e)
{
System.Console.Out.Write(Convert.ToChar(this.ACIA.TDR));
this.ACIA.MarkTransmitComplete();
Console.Out.Write(Convert.ToChar(ACIA.TDR));
ACIA.MarkTransmitComplete();
}
private void UpdateAciaPins()
{
this.ACIA.DATA = this.Data;
this.ACIA.RS.Match(this.Address.Word & (ushort)Bits.Bit0);
this.ACIA.CS0.Match(this.Address.Word & (ushort)Bits.Bit15);
this.ACIA.CS1.Match(this.Address.Word & (ushort)Bits.Bit13);
this.ACIA.CS2.Match(this.Address.Word & (ushort)Bits.Bit14);
ACIA.DATA = Data;
ACIA.RS.Match(Address.Word & (ushort)Bits.Bit0);
ACIA.CS0.Match(Address.Word & (ushort)Bits.Bit15);
ACIA.CS1.Match(Address.Word & (ushort)Bits.Bit13);
ACIA.CS2.Match(Address.Word & (ushort)Bits.Bit14);
}
private bool AccessAcia()
{
this.ACIA.E.Raise();
ACIA.E.Raise();
try
{
this.ACIA.Tick();
return this.ACIA.Activated;
ACIA.Tick();
return ACIA.Activated;
}
finally
{
this.ACIA.E.Lower();
ACIA.E.Lower();
}
}
}
MC6809/MC6809.Test/TestHarness.cs
+1
View File
@@ -4,6 +4,7 @@
namespace EightBit
{
using MC6809.Test;
using System.Diagnostics;
internal sealed class TestHarness(Configuration configuration)
MC6809/MC6809.cs
+46 -19
View File
@@ -580,17 +580,19 @@ namespace MC6809
private byte Pop(Register16 stack)
{
var read = this.MemoryRead(stack);
_ = this.MemoryRead(stack);
stack.Increment();
return read;
return this.Bus.Data;
}
private byte PopS() => this.Pop(this.S);
private Register16 PopWord(Register16 stack)
{
this.Intermediate.High = this.Pop(stack);
this.Intermediate.Low = this.Pop(stack);
this.Pop(stack);
this.Intermediate.High = this.Bus.Data;
this.Pop(stack);
this.Intermediate.Low = this.Bus.Data;
return this.Intermediate;
}
@@ -600,7 +602,8 @@ namespace MC6809
private Register16 Address_relative_byte()
{
var offset = (sbyte)this.FetchByte();
this.FetchByte();
var offset = (sbyte)this.Bus.Data;
this.Intermediate.Word = (ushort)(this.PC.Word + offset);
return this.Intermediate;
}
@@ -614,7 +617,8 @@ namespace MC6809
private Register16 Address_direct()
{
this.Intermediate.Assign(this.FetchByte(), this.DP);
this.FetchByte();
this.Intermediate.Assign(this.Bus.Data, this.DP);
return this.Intermediate;
}
@@ -634,7 +638,8 @@ namespace MC6809
private Register16 Address_indexed()
{
var type = this.FetchByte();
this.FetchByte();
var type = this.Bus.Data;
var r = this.RR((type & (byte)(Bits.Bit6 | Bits.Bit5)) >> 5);
if ((type & (byte)Bits.Bit7) != 0)
@@ -672,7 +677,8 @@ namespace MC6809
break;
case 0b1000: // n,R (eight-bit)
this.Tick();
this.Intermediate.Word = (ushort)(r.Word + (sbyte)this.FetchByte());
this.FetchByte();
this.Intermediate.Word = (ushort)(r.Word + (sbyte)this.Bus.Data);
break;
case 0b1001: // n,R (sixteen-bit)
this.Tick(4);
@@ -715,13 +721,29 @@ namespace MC6809
return this.Intermediate;
}
private byte AM_immediate_byte() => this.FetchByte();
private byte AM_immediate_byte()
{
this.FetchByte();
return this.Bus.Data;
}
private byte AM_direct_byte() => this.MemoryRead(this.Address_direct());
private byte AM_direct_byte()
{
this.MemoryRead(this.Address_direct());
return this.Bus.Data;
}
private byte AM_indexed_byte() => this.MemoryRead(this.Address_indexed());
private byte AM_indexed_byte()
{
this.MemoryRead(this.Address_indexed());
return this.Bus.Data;
}
private byte AM_extended_byte() => this.MemoryRead(this.Address_extended());
private byte AM_extended_byte()
{
this.MemoryRead(this.Address_extended());
return this.Bus.Data;
}
private Register16 AM_immediate_word() => this.FetchWord();
@@ -859,25 +881,29 @@ namespace MC6809
if ((data & (byte)Bits.Bit0) != 0)
{
this.Tick();
this.CC = this.Pop(stack);
this.Pop(stack);
this.CC = this.Bus.Data;
}
if ((data & (byte)Bits.Bit1) != 0)
{
this.Tick();
this.A = this.Pop(stack);
this.Pop(stack);
this.A = this.Bus.Data;
}
if ((data & (byte)Bits.Bit2) != 0)
{
this.Tick();
this.B = this.Pop(stack);
this.Pop(stack);
this.B = this.Bus.Data;
}
if ((data & (byte)Bits.Bit3) != 0)
{
this.Tick();
this.DP = this.Pop(stack);
this.Pop(stack);
this.DP = this.Bus.Data;
}
if ((data & (byte)Bits.Bit4) != 0)
@@ -1050,7 +1076,8 @@ namespace MC6809
}
else
{
this.Execute(this.FetchByte());
this.FetchByte();
this.Execute(this.Bus.Data);
}
}
@@ -1079,8 +1106,8 @@ namespace MC6809
{
switch (this.OpCode)
{
case 0x10: this.prefix10 = true; this.Execute(this.FetchByte()); break;
case 0x11: this.prefix11 = true; this.Execute(this.FetchByte()); break;
case 0x10: this.prefix10 = true; this.FetchByte(); this.Execute(this.Bus.Data); break;
case 0x11: this.prefix11 = true; this.FetchByte(); this.Execute(this.Bus.Data); break;
// ABX
case 0x3a: this.Tick(3); this.X.Word += this.B; break; // ABX (inherent)