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Built basic debugger UI and execution framework; a few bugfixes. CPU now executes uCode up until the first STARTF (unimplemented).

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This commit is contained in:
Josh Dersch
2015-09-01 17:06:57 -07:00
parent c4f8fe951f
commit 0ced1a2ef8
10 changed files with 1283 additions and 52 deletions
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65
Contralto/Memory/MemoryBus.cs
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@@ -10,21 +10,46 @@ namespace Contralto.Memory
{
LoadAddress,
Read,
Load
Store
}
public static class MemoryBus
public class MemoryBus
{
static MemoryBus()
public MemoryBus()
{
_mem = new Memory();
Reset();
}
public void Reset()
{
_memoryCycle = 0;
_memoryAddress = 0;
_memoryData = 0;
_memoryOperationActive = false;
}
public static void Clock()
public ushort MAR
{
get { return _memoryAddress; }
}
public ushort MD
{
get { return _memoryData; }
}
public int Cycle
{
get { return _memoryCycle; }
}
public bool Active
{
get { return _memoryOperationActive; }
}
public void Clock()
{
_memoryCycle++;
if (_memoryOperationActive)
@@ -50,7 +75,7 @@ namespace Contralto.Memory
}
}
public static bool Ready(MemoryOperation op)
public bool Ready(MemoryOperation op)
{
if (_memoryOperationActive)
{
@@ -64,7 +89,7 @@ namespace Contralto.Memory
// Read operations take place on cycles 5 and 6
return _memoryCycle > 4;
case MemoryOperation.Load:
case MemoryOperation.Store:
// Write operations take place on cycles 3 and 4
return _memoryCycle > 2;
@@ -79,7 +104,7 @@ namespace Contralto.Memory
}
}
public static void LoadMAR(ushort address)
public void LoadMAR(ushort address)
{
if (_memoryOperationActive)
{
@@ -95,7 +120,7 @@ namespace Contralto.Memory
}
}
public static ushort ReadMD()
public ushort ReadMD()
{
if (_memoryOperationActive)
{
@@ -141,7 +166,7 @@ namespace Contralto.Memory
}
}
public static void LoadMD(ushort data)
public void LoadMD(ushort data)
{
if (_memoryOperationActive)
{
@@ -154,12 +179,14 @@ namespace Contralto.Memory
throw new InvalidOperationException("Unexpected microcode behavior -- LoadMD during incorrect memory cycle.");
case 3:
_memoryData = data; // Only really necessary to show in debugger
// Start of doubleword write:
WriteToBus(_memoryAddress, data);
_doubleWordStore = true;
break;
case 4:
case 4:
_memoryData = data; // Only really necessary to show in debugger
WriteToBus(_doubleWordStore ? (ushort)(_memoryAddress ^ 1) : _memoryAddress, data);
break;
}
@@ -172,7 +199,7 @@ namespace Contralto.Memory
/// </summary>
/// <param name="address"></param>
/// <returns></returns>
private static ushort ReadFromBus(ushort address)
private ushort ReadFromBus(ushort address)
{
// TODO: actually dispatch to I/O
return _mem.Read(address);
@@ -184,22 +211,22 @@ namespace Contralto.Memory
/// <param name="address"></param>
/// <param name="data"></param>
/// <returns></returns>
private static void WriteToBus(ushort address, ushort data)
private void WriteToBus(ushort address, ushort data)
{
_mem.Load(address, data);
}
private static Memory _mem;
private static bool _memoryOperationActive;
private static int _memoryCycle;
private static ushort _memoryAddress;
private Memory _mem;
private bool _memoryOperationActive;
private int _memoryCycle;
private ushort _memoryAddress;
// Buffered read data (on cycles 3 and 4)
private static ushort _memoryData;
private static ushort _memoryData2;
private ushort _memoryData;
private ushort _memoryData2;
// Indicates a double-word store (started on cycle 3)
private static bool _doubleWordStore;
private bool _doubleWordStore;
}
}