internal static void SetDisassembly(Sim6502 processor, HostLogger logger)
{
if (logger == null || !logger.IsDebugEnabled)
{
return;
}
EAddressingMode addressMode = Sim6502Utility.GetAddressingMode(processor.RegisterIR);
int currentProgramCounter = processor.RegisterPC;
currentProgramCounter = processor.WrapProgramCounter(++currentProgramCounter);
int?address1 = processor.ReadMemoryValueWithoutCycle(currentProgramCounter);
currentProgramCounter = processor.WrapProgramCounter(++currentProgramCounter);
int?address2 = processor.ReadMemoryValueWithoutCycle(currentProgramCounter);
string disassembledStep = string.Empty;
switch (addressMode)
{
case EAddressingMode.Absolute:
disassembledStep = string.Format("${0}{1}", address2.Value.ToString("X").PadLeft(2, '0'), address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.AbsoluteX:
disassembledStep = string.Format("${0}{1},X", address2.Value.ToString("X").PadLeft(2, '0'), address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.AbsoluteY:
disassembledStep = string.Format("${0}{1},Y", address2.Value.ToString("X").PadLeft(2, '0'), address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.Accumulator:
address1 = null;
address2 = null;
disassembledStep = "A";
break;
case EAddressingMode.Immediate:
disassembledStep = string.Format("#${0}", address1.Value.ToString("X").PadLeft(4, '0'));
address2 = null;
break;
case EAddressingMode.Implicit:
address1 = null;
address2 = null;
break;
case EAddressingMode.Indirect:
disassembledStep = string.Format("(${0}{1})", address2.Value.ToString("X").PadLeft(2, '0'), address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.IndirectX:
address2 = null;
disassembledStep = string.Format("(${0},X)", address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.IndirectY:
address2 = null;
disassembledStep = string.Format("(${0}),Y", address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.Relative:
var valueToMove = (byte)address1.Value;
var movement = valueToMove > 127 ? (valueToMove - 255) : valueToMove;
var newProgramCounter = processor.RegisterPC + movement;
//This makes sure that we always land on the correct spot for a positive number
if (movement >= 0)
{
newProgramCounter++;
}
var stringAddress = processor.RegisterPC.ToString("X").PadLeft(4, '0');
// address1 = int.Parse(stringAddress.Substring(0, 2), NumberStyles.AllowHexSpecifier);
address2 = null; // int.Parse(stringAddress.Substring(2, 2), NumberStyles.AllowHexSpecifier);
disassembledStep = string.Format("${0}", newProgramCounter.ToString("X").PadLeft(4, '0'));
break;
case EAddressingMode.ZeroPage:
address2 = null;
disassembledStep = string.Format("${0}", address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.ZeroPageX:
address2 = null;
disassembledStep = string.Format("${0},X", address1.Value.ToString("X").PadLeft(2, '0'));
break;
case EAddressingMode.ZeroPageY:
address2 = null;
disassembledStep = string.Format("${0},Y", address1.Value.ToString("X").PadLeft(4, '0'));
break;
default:
throw new InvalidEnumArgumentException("Invalid Addressing Mode");
}
string opcodeAsString = processor.RegisterIR.ConvertOpCodeIntoString();
logger.Debug("{0} : {1} {2} {3} {4} {5} A: {6} X: {7} Y: {8} SP {9} N: {10} V: {11} B: {12} D: {13} I: {14} Z: {15} C: {16} $0D={17}",
processor.RegisterPC.ToString("X4"),
processor.RegisterIR.ToString("X2"),
address1.HasValue ? address1.Value.ToString("X").PadLeft(2, '0') : " ",
address2.HasValue ? address2.Value.ToString("X").PadLeft(2, '0') : " ",
opcodeAsString,
disassembledStep.PadRight(13 - opcodeAsString.Length, ' '),
processor.RegisterA.ToString("X").PadLeft(3, '0'),
processor.RegisterX.ToString("X").PadLeft(3, '0'),
processor.RegisterY.ToString("X").PadLeft(3, '0'),
processor.RegisterSP.ToString("X").PadLeft(3, '0'),
Convert.ToInt16(processor.FlagN),
Convert.ToInt16(processor.FlagV),
0,
Convert.ToInt16(processor.FlagD),
Convert.ToInt16(processor.FlagI),
Convert.ToInt16(processor.FlagZ),
Convert.ToInt16(processor.FlagC),
processor.ReadMemoryValueWithoutCycle(0x0D).ToString("X"));
}