private ushort ReadControlRegister(ushort operand, RegControl index)
{
switch (index)
{
case RegControl.FL:
return(FL);
case RegControl.PC:
return(PC);
case RegControl.PS:
if (PS_S)
{
return(m_PS);
}
Interrupt_UnPrivFault(operand);
return(0);
case RegControl.USP:
return(USP);
case RegControl.SSP:
if (PS_S)
{
return(SSP);
}
return(USP);
default:
Interrupt_UndefFault(operand);
return(0);
}
}
/// <summary>
/// Executes an ALU operation.
/// </summary>
/// <param name="operand">Input: machine code word</param>
/// <param name="value">Output: result value of operation</param>
/// <param name="destination">Output: index of general register result should be written to.</param>
private void BitPatternALU(ushort operand, out ushort value, out RegGeneral destination)
{
ushort address;
// Decode the operand word's constituent bits. FEDC BA98 7654 3210
// SAAA rrrE OOOO ORRR
int addressingMode = (operand & 0x7000) >> 12;
RegGeneral source = (RegGeneral)((operand & 0x0E00) >> 9);
bool eightBitMode = (operand & 0x0100) != 0;
destination = (RegGeneral)(operand & 0x0007); // R = destination register
SegmentIndex dataSeg = (operand & 0x8000) != 0 ? SegmentIndex.ES : SegmentIndex.DS;
switch (addressingMode) // will always be between 0x0 and 0x7
{
case 0: // Addressing mode: Immediate (r == 0), Absolute (r == 1), else Control Register.
if (source == 0) // Immediate
{
value = eightBitMode ? ReadMemInt8(PC, SegmentIndex.CS) : ReadMemInt16(PC, SegmentIndex.CS);
PC += 2; // advance PC two bytes because we're reading an immediate value.
}
else if ((int)source == 1) // Absolute
{
address = ReadMemInt16(PC, SegmentIndex.CS);
PC += 2; // advance PC two bytes because we're reading an immediate value.
value = eightBitMode ? ReadMemInt8(address, dataSeg) : ReadMemInt16(address, dataSeg);
}
else // Control Register
{
RegControl cr = (RegControl)((operand & 0x0700) >> 8);
value = ReadControlRegister(operand, cr);
}
break;
case 1: // Addressing mode: Register
value = R[(int)source];
break;
case 2: // Addressing mode: Indirect
value = eightBitMode ? ReadMemInt8(R[(int)source], dataSeg) : ReadMemInt16(R[(int)source], dataSeg);
break;
case 3: // Addressing mode: Absolute Offset AKA Indirect Offset
address = (ushort)(R[(int)source] + ReadMemInt16(PC, SegmentIndex.CS));
PC += 2; // advance PC two bytes because we're reading an immediate value.
value = eightBitMode ? ReadMemInt8(address, dataSeg) : ReadMemInt16(address, dataSeg);
break;
default: // addressing of 0x4 ~ 0x7 is an Indirect Indexed operation.
int indexRegister = addressingMode; // bit pattern is 1ii, where ii = r4 - r7.
address = (ushort)(R[(int)source] + R[indexRegister]);
value = eightBitMode ? ReadMemInt8(address, dataSeg) : ReadMemInt16(address, dataSeg);
break;
}
}
/// <summary>
/// Executes a STOre operation (same bit pattern as ALU, but writes a value from r0 to destination).
/// </summary>
/// <param name="operand">Input: machine code word</param>
/// <param name="destAddress">Output: memory address that is the destination of the operation</param>
/// <param name="source">Output: general register that is the source of the operation</param>
private void BitPatternSTO(ushort operand, out ushort destAddress, out RegGeneral source)
{
// Decode the operand word's constituent bits. FEDC BA98 7654 3210
// SAAA rrrE OOOO ORRR
int addressingMode = (operand & 0x7000) >> 12;
RegGeneral addrRegister = (RegGeneral)((operand & 0x0E00) >> 9);
source = (RegGeneral)(operand & 0x0007); // R = source register
switch (addressingMode) // will always be between 0x0 and 0x7
{
case 0: // Immediate (r == 0), Absolute (r == 1), else Control Register
if (addrRegister == 0)
{
// Immediate - no such addressing mode for STO.
source = RegGeneral.None;
destAddress = 0;
Interrupt_UndefFault(operand);
}
else if ((int)addrRegister == 1)
{
destAddress = ReadMemInt16(PC, SegmentIndex.CS);
PC += 2; // advance PC two bytes because we're reading an immediate value.
}
else
{
RegControl cr = (RegControl)((operand & 0x0700) >> 8);
WriteControlRegister(operand, cr, R[(int)source]);
// set source = none so calling function doesn't attempt to interpret this as well.
source = RegGeneral.None;
destAddress = 0;
}
break;
case 1: // Register - no such addressing mode for STO.
source = RegGeneral.None;
destAddress = 0;
Interrupt_UndefFault(operand);
break;
case 2: // Indirect
destAddress = R[(int)addrRegister];
break;
case 3: // Absolute Offset AKA Indirect Offset
destAddress = (ushort)(R[(int)addrRegister] + ReadMemInt16(PC, SegmentIndex.CS));
PC += 2; // advance PC two bytes because we're reading an immediate value.
break;
default: // $8-$F are Indirect Indexed operations.
int indexRegister = addressingMode; // bit pattern is 01ii, indicating r4 - r7.
destAddress = (ushort)(R[(int)source] + R[indexRegister]);
break;
}
}
private void LoadControls(string regsettings)
{
var properties = test.GetProperties(new MemberInfo());
string groupname = "";
Panel grpPanel = null;
XDocument doc = XDocument.Load(regsettings);
XElement root = doc.Root;
foreach (XElement elem in root.Elements().OrderBy(e => e.Attribute("Group").Value))
{
if (elem.Attribute("Group").Value != groupname)
{
if (grpPanel != null && grpPanel.Controls.Count > 0)
{
mControls.Controls.Add(grpPanel);
}
groupname = elem.Attribute("Group").Value;
grpPanel = new Panel {
ID = "pnl" + groupname, GroupingText = test.SplitCamelCase(groupname)
};
}
var prop = properties.SingleOrDefault(p => p.Name == elem.Name.LocalName);
Registration pr = (Registration)prop.GetCustomAttributes(false)[0];
var isVisible = Convert.ToBoolean(elem.Attribute("Show").Value);
var isRequired = Convert.ToBoolean(elem.Attribute("Require").Value);
if (isVisible)
{
RegControl ctl = new RegControl()
{
LabelText = test.SplitCamelCase(elem.Name.LocalName),
ControlID = elem.Name.LocalName,
ControlType = pr.Control,
InvalidMessage = isRequired ? elem.Name.LocalName + " Is required" : "",
Show = true,
Required = isRequired,
ClientScript = "false",
CssClass = isRequired ? "label_mandatory" : "label_not_mandatory"
};
if (grpPanel != null)
{
grpPanel.Controls.Add(ctl);
}
}
}
if (grpPanel != null && grpPanel.Controls.Count > 0)
{
mControls.Controls.Add(grpPanel);
}
}
private void WriteControlRegister(ushort operand, RegControl index, ushort value)
{
switch (index)
{
case RegControl.FL:
FL = value;
break;
case RegControl.PC:
PC = value;
break;
case RegControl.PS:
if (PS_S)
{
PS = value;
}
else
{
Interrupt_UnPrivFault(operand);
}
break;
case RegControl.USP:
USP = value;
break;
case RegControl.SSP:
if (PS_S)
{
SSP = value;
}
else
{
USP = value;
}
break;
default:
Interrupt_UndefFault(operand);
break;
}
}
private string NameOfRegSP(RegControl register)
{
switch (register)
{
case RegControl.FL:
return("FL");
case RegControl.PC:
return("PC");
case RegControl.PS:
return("PS");
case RegControl.USP:
return("USP");
case RegControl.SSP:
return("SP");
default:
return("??");
}
}
private Panel LoadGroupControls(string groupname)
{
var properties = RegHelper.GetProperties(new MemberInfo());
Panel grpPanel = null;
_memberFields = XDocument.Load(_regsettings);
XElement root = _memberFields.Root;
//get all the controls to be shown and order by groupname so we can arrange on the wizard
grpPanel = new Panel { ID = "pnl" + groupname, GroupingText = RegHelper.SplitCamelCase(groupname) };
foreach (XElement elem in root.Elements().Where(a => a.Attribute("Show").Value == "true" && a.Attribute("Group").Value == groupname))
{
//get the custom attributes for the current property so we can get the control to use
var prop = properties.SingleOrDefault(p => p.Name == elem.Name.LocalName);
Registration attr = (Registration)prop.GetCustomAttributes(false)[0];
//var isVisible = Convert.ToBoolean(elem.Attribute("Show").Value);
var isRequired = Convert.ToBoolean(elem.Attribute("Require").Value);
RegControl ctl = new RegControl()
{
ValidationGroup = CreateUserWizard1.ID,
LabelText = RegHelper.SplitCamelCase(elem.Name.LocalName),
ControlID = elem.Name.LocalName,
ControlType = attr.Control,
InvalidMessage = isRequired ? elem.Name.LocalName + " Is required" : "",
Show = true,
Required = isRequired,
ClientScript = "true",
CssClass = isRequired ? "label_mandatory" : "label_not_mandatory"
};
//add the new control to the panel
grpPanel.Controls.Add(ctl);
}
return grpPanel;
}
private void WriteControlRegister(ushort operand, RegControl index, ushort value)
{
switch (index) {
case RegControl.FL:
FL = value;
break;
case RegControl.PC:
PC = value;
break;
case RegControl.PS:
if (PS_S)
PS = value;
else
Interrupt_UnPrivFault(operand);
break;
case RegControl.USP:
USP = value;
break;
case RegControl.SSP:
if (PS_S)
SSP = value;
else
USP = value;
break;
default:
Interrupt_UndefFault(operand);
break;
}
}
private ushort ReadControlRegister(ushort operand, RegControl index)
{
switch (index) {
case RegControl.FL:
return FL;
case RegControl.PC:
return PC;
case RegControl.PS:
if (PS_S)
return m_PS;
Interrupt_UnPrivFault(operand);
return 0;
case RegControl.USP:
return USP;
case RegControl.SSP:
if (PS_S)
return SSP;
return USP;
default:
Interrupt_UndefFault(operand);
return 0;
}
}
private string NameOfRegSP(RegControl register)
{
switch (register) {
case RegControl.FL:
return "FL";
case RegControl.PC:
return "PC";
case RegControl.PS:
return "PS";
case RegControl.USP:
return "USP";
case RegControl.SSP:
return "SP";
default:
return "??";
}
}
private string DisassembleALU(string name, ushort operand, ushort nextword, ushort address, bool showMemoryContents, out ushort instructionSize)
{
int addressingmode = (operand & 0x7000) >> 12;
RegGeneral regDest = (RegGeneral)(operand & 0x0007);
RegGeneral regSrc = (RegGeneral)((operand & 0x0E00) >> 9);
bool isEightBit = (operand & 0x0100) != 0;
SegmentIndex segData = (operand & 0x8000) != 0 ? SegmentIndex.ES : SegmentIndex.DS;
switch (addressingmode)
{
case 0:
if (regSrc == 0) // immediate
{
if (name == "STO")
{
instructionSize = 2;
return("???");
}
instructionSize = 4;
string disasm =
$"{name + (isEightBit ? ".8" : string.Empty),-8}{NameOfRegGP(regDest)}, ${nextword:X4}";
if (showMemoryContents)
{
disasm = AppendMemoryContents(disasm, nextword);
}
return(disasm);
}
if ((int)regSrc == 1) // absolute
{
instructionSize = 4;
string disasm =
$"{name + (isEightBit ? ".8" : string.Empty),-8}{NameOfRegGP(regDest)}, [${nextword:X4}]";
if (showMemoryContents)
{
disasm = AppendMemoryContents(disasm, DebugReadMemory(nextword, segData));
}
return(disasm);
}
else // control register
{
instructionSize = 2;
RegControl cr = (RegControl)((operand & 0x0700) >> 8);
string disasm = $"{name,-8}{NameOfRegGP(regDest)}, {NameOfRegSP(cr)}";
if (showMemoryContents)
{
disasm = AppendMemoryContents(disasm, nextword);
}
return(disasm);
}
case 1: // Register
instructionSize = 2;
return
($"{name + (isEightBit ? ".8" : string.Empty),-8}{NameOfRegGP(regDest)}, {NameOfRegGP(regSrc),-12}(${R[(int)regSrc]:X4})");
case 2: // Indirect
instructionSize = 2;
return
($"{name + (isEightBit ? ".8" : string.Empty),-8}{NameOfRegGP(regDest)}, [{NameOfRegGP(regSrc)}] (${DebugReadMemory(R[(int)regSrc], segData):X4})");
case 3: // Indirect Offset (also Absolute Offset)
instructionSize = 4;
return
($"{name + (isEightBit ? ".8" : string.Empty),-8}{NameOfRegGP(regDest)}, [{NameOfRegGP(regSrc)},${nextword:X4}] (${DebugReadMemory((ushort)(R[(int)regSrc] + nextword), segData):X4})");
default: // $4 - $7 are Indirect Indexed
instructionSize = 2;
RegGeneral regIndex = (RegGeneral)((operand & 0x7000) >> 12);
return
($"{name + (isEightBit ? ".8" : string.Empty),-8}{NameOfRegGP(regDest)}, [{NameOfRegGP(regSrc)},{NameOfRegGP(regIndex)}] (${DebugReadMemory((ushort)(R[(int)regSrc] + R[(int)regIndex]), segData):X4})");
}
}
