public byte Execute(OpCodeDefinition opCodeDefinition, IAddressingMode addressingMode, CPUMemory memory, CPURegisters registers, byte operand1, byte operand2)
{
var operationValue = addressingMode.GetValue(memory, registers, operand1, operand2, out bool pageBoundaryCrossed);
registers.N_NegativeFlag = (byte)((operationValue & 0x80) >> 7);
registers.Z_ZeroFlag = (byte)(operationValue == 0 ? 1 : 0);
registers.X = operationValue;
return((byte)(opCodeDefinition.ExecutionCycles + (opCodeDefinition.AddExecutionCycleOnPageBoundaryCross && pageBoundaryCrossed ? 1 : 0)));
}
public string GetSyntax(OpCodeDefinition opCodeDefinition, IAddressingMode addressingMode, CPUMemory memory, CPURegisters registers, byte operand1, byte operand2)
{
if (opCodeDefinition.AddressingMode == AddressingMode.IMM)
{
return(string.Empty);
}
else
{
var operationValue = addressingMode.GetValue(memory, registers, operand1, operand2, out _);
return($"= {operationValue:X02}");
}
}
public byte Execute(OpCodeDefinition opCodeDefinition, IAddressingMode addressingMode, CPUMemory memory, CPURegisters registers, byte operand1, byte operand2)
{
var operationAddress = addressingMode.GetAddress(memory, registers, operand1, operand2, out _);
var operationValue = addressingMode.GetValue(memory, registers, operationAddress);
var result = operationValue + 1;
registers.N_NegativeFlag = (byte)((result & 0x80) >> 7);
registers.Z_ZeroFlag = (byte)((byte)result == 0 ? 1 : 0);
addressingMode.SetValue(memory, registers, operationAddress, (byte)result);
return(opCodeDefinition.ExecutionCycles);
}
public byte Execute(OpCodeDefinition opCodeDefinition, IAddressingMode addressingMode, CPUMemory memory, CPURegisters registers, byte operand1, byte operand2)
{
var operationAddress = addressingMode.GetAddress(memory, registers, operand1, operand2, out bool pageBoundaryCrossed);
var operationValue = addressingMode.GetValue(memory, registers, operationAddress);
var result = operationValue << 1 | registers.C_CarryFlag;
registers.N_NegativeFlag = (byte)((result & 0x80) >> 7);
registers.C_CarryFlag = (byte)((operationValue & 0x80) >> 7);
registers.Z_ZeroFlag = (byte)((byte)result == 0x00 ? 1 : 0);
addressingMode.SetValue(memory, registers, operationAddress, (byte)result);
return((byte)(opCodeDefinition.ExecutionCycles + (opCodeDefinition.AddExecutionCycleOnPageBoundaryCross && pageBoundaryCrossed ? 1 : 0)));
}
public byte Execute(OpCodeDefinition opCodeDefinition, IAddressingMode addressingMode, CPUMemory memory, CPURegisters registers, byte operand1, byte operand2)
{
var operationValue = addressingMode.GetValue(memory, registers, operand1, operand2, out bool pageBoundaryCrossed);
var result = registers.A - operationValue - (1 - registers.C_CarryFlag);
registers.N_NegativeFlag = (byte)((result & 0x80) >> 7);
registers.Z_ZeroFlag = (byte)((byte)result == 0 ? 1 : 0);
registers.C_CarryFlag = (byte)(result >= 0x00 ? 1 : 0);
registers.V_OverflowFlag =
(byte)((result < 0x80 && registers.A >= 0x80) ||
(result >= 0x80 && registers.A < 0x80) ? 1 : 0);
registers.A = (byte)result;
return((byte)(opCodeDefinition.ExecutionCycles + (opCodeDefinition.AddExecutionCycleOnPageBoundaryCross && pageBoundaryCrossed ? 1 : 0)));
}
