/// <summary>
/// Reads a byte of data from a specified port address
/// </summary>
public override byte ReadPort(ushort port)
{
BitArray portBits = new BitArray(BitConverter.GetBytes(port));
byte portUpper = (byte)(port >> 8);
byte portLower = (byte)(port & 0xff);
int result = 0xff;
if (DecodeINPort(port) == PortDevice.GateArray)
{
GateArray.ReadPort(port, ref result);
}
else if (DecodeINPort(port) == PortDevice.CRCT)
{
CRCT.ReadPort(port, ref result);
}
else if (DecodeINPort(port) == PortDevice.ROMSelect)
{
}
else if (DecodeINPort(port) == PortDevice.Printer)
{
}
else if (DecodeINPort(port) == PortDevice.PPI)
{
PPI.ReadPort(port, ref result);
}
else if (DecodeINPort(port) == PortDevice.Expansion)
{
}
return((byte)result);
}
public void SyncState(Serializer ser)
{
ser.BeginSection("CPCMachine");
ser.Sync("FrameCompleted", ref FrameCompleted);
ser.Sync("OverFlow", ref OverFlow);
ser.Sync("FrameCount", ref FrameCount);
ser.Sync("_frameCycles", ref _frameCycles);
ser.Sync("inputRead", ref inputRead);
ser.Sync("LastFrameStartCPUTick", ref LastFrameStartCPUTick);
ser.Sync("ROMLower", ref ROMLower, false);
ser.Sync("ROM0", ref ROM0, false);
ser.Sync("ROM7", ref ROM7, false);
ser.Sync("RAM0", ref RAM0, false);
ser.Sync("RAM1", ref RAM1, false);
ser.Sync("RAM2", ref RAM2, false);
ser.Sync("RAM3", ref RAM3, false);
ser.Sync("RAM4", ref RAM4, false);
ser.Sync("RAM5", ref RAM5, false);
ser.Sync("RAM6", ref RAM6, false);
ser.Sync("RAM7", ref RAM7, false);
ser.Sync("UpperROMPosition", ref UpperROMPosition);
ser.Sync("UpperROMPaged", ref UpperROMPaged);
ser.Sync("LowerROMPaged", ref LowerROMPaged);
ser.Sync("RAMConfig", ref RAMConfig);
ser.Sync("RAM64KBank", ref RAM64KBank);
CRCT.SyncState(ser);
//CRT.SyncState(ser);
GateArray.SyncState(ser);
KeyboardDevice.SyncState(ser);
TapeBuzzer.SyncState(ser);
AYDevice.SyncState(ser);
ser.Sync("tapeMediaIndex", ref tapeMediaIndex);
if (ser.IsReader)
{
TapeMediaIndex = tapeMediaIndex;
}
TapeDevice.SyncState(ser);
ser.Sync("diskMediaIndex", ref diskMediaIndex);
if (ser.IsReader)
{
DiskMediaIndex = diskMediaIndex;
}
if (UPDDiskDevice != null)
{
UPDDiskDevice.SyncState(ser);
}
ser.EndSection();
}
public void SyncState(Serializer ser)
{
ser.BeginSection("CPCMachine");
ser.Sync(nameof(FrameCompleted), ref FrameCompleted);
ser.Sync(nameof(OverFlow), ref OverFlow);
ser.Sync(nameof(FrameCount), ref FrameCount);
ser.Sync(nameof(_frameCycles), ref _frameCycles);
ser.Sync(nameof(inputRead), ref inputRead);
ser.Sync(nameof(LastFrameStartCPUTick), ref LastFrameStartCPUTick);
ser.Sync(nameof(ROMLower), ref ROMLower, false);
ser.Sync(nameof(ROM0), ref ROM0, false);
ser.Sync(nameof(ROM7), ref ROM7, false);
ser.Sync(nameof(RAM0), ref RAM0, false);
ser.Sync(nameof(RAM1), ref RAM1, false);
ser.Sync(nameof(RAM2), ref RAM2, false);
ser.Sync(nameof(RAM3), ref RAM3, false);
ser.Sync(nameof(RAM4), ref RAM4, false);
ser.Sync(nameof(RAM5), ref RAM5, false);
ser.Sync(nameof(RAM6), ref RAM6, false);
ser.Sync(nameof(RAM7), ref RAM7, false);
ser.Sync(nameof(UpperROMPosition), ref UpperROMPosition);
ser.Sync(nameof(UpperROMPaged), ref UpperROMPaged);
ser.Sync(nameof(LowerROMPaged), ref LowerROMPaged);
ser.Sync(nameof(RAMConfig), ref RAMConfig);
ser.Sync(nameof(RAM64KBank), ref RAM64KBank);
CRCT.SyncState(ser);
//CRT.SyncState(ser);
GateArray.SyncState(ser);
KeyboardDevice.SyncState(ser);
TapeBuzzer.SyncState(ser);
AYDevice.SyncState(ser);
ser.Sync(nameof(tapeMediaIndex), ref tapeMediaIndex);
if (ser.IsReader)
{
TapeMediaIndex = tapeMediaIndex;
}
TapeDevice.SyncState(ser);
ser.Sync(nameof(diskMediaIndex), ref diskMediaIndex);
if (ser.IsReader)
{
DiskMediaIndex = diskMediaIndex;
}
if (UPDDiskDevice != null)
{
UPDDiskDevice.SyncState(ser);
}
ser.EndSection();
}
/// <summary>
/// Called every CPU cycle
/// In reality the GA is clocked at 16Mhz (4 times the frequency of the CPU)
/// Therefore this method has to take care of:
/// 4 GA cycles
/// 1 CRCT cycle every 4 calls
/// 1 PSG cycle every 4 calls
/// 1 CPU cycle (uncontended)
/// </summary>
public void ClockCycle()
{
// gatearray uses 4-phase clock to supply clocks to other devices
switch (ClockCounter)
{
case 0:
CRCT.ClockCycle();
WaitLine = false;
break;
case 1:
WaitLine = true;
// detect new scanline and upcoming new frame on next render cycle
//FrameDetector();
break;
case 2:
// video fetch
WaitLine = true;
//FetchByte(1);
break;
case 3:
// video fetch and render
WaitLine = true;
//FetchByte(2);
GACharacterCycle();
//PixelGenerator();
break;
}
if (!HSYNC && CRCT.HSYNC)
{
HSYNC = true;
}
// run the interrupt generator routine
InterruptGenerator();
if (!CRCT.HSYNC)
{
HSYNC = false;
}
// conditional CPU cycle
DoConditionalCPUCycle();
AdvanceClock();
}
/// <summary>
/// Reads a byte of data from a specified port address
/// </summary>
/// <param name="port"></param>
/// <returns></returns>
public override byte ReadPort(ushort port)
{
BitArray portBits = new BitArray(BitConverter.GetBytes(port));
byte portUpper = (byte)(port >> 8);
byte portLower = (byte)(port & 0xff);
int result = 0xff;
if (DecodeINPort(port) == PortDevice.GateArray)
{
GateArray.ReadPort(port, ref result);
}
else if (DecodeINPort(port) == PortDevice.CRCT)
{
CRCT.ReadPort(port, ref result);
}
else if (DecodeINPort(port) == PortDevice.ROMSelect)
{
}
else if (DecodeINPort(port) == PortDevice.Printer)
{
}
else if (DecodeINPort(port) == PortDevice.PPI)
{
PPI.ReadPort(port, ref result);
}
else if (DecodeINPort(port) == PortDevice.Expansion)
{
if (!port.Bit(7))
{
// FDC
if (port.Bit(8) && !port.Bit(0))
{
// FDC status register
UPDDiskDevice.ReadStatus(ref result);
}
if (port.Bit(8) && port.Bit(0))
{
// FDC data register
UPDDiskDevice.ReadData(ref result);
}
}
}
return((byte)result);
}
/// <summary>
/// Writes a byte of data to a specified port address
/// Because of the port decoding, multiple devices can be written to
/// </summary>
public override void WritePort(ushort port, byte value)
{
BitArray portBits = new BitArray(BitConverter.GetBytes(port));
BitArray dataBits = new BitArray(BitConverter.GetBytes(value));
byte portUpper = (byte)(port >> 8);
byte portLower = (byte)(port & 0xff);
var devs = DecodeOUTPort(port);
foreach (var d in devs)
{
if (d == PortDevice.GateArray)
{
GateArray.WritePort(port, value);
}
else if (d == PortDevice.RAMManagement)
{
// not present in the unexpanded CPC464
}
else if (d == PortDevice.CRCT)
{
CRCT.WritePort(port, value);
}
else if (d == PortDevice.ROMSelect)
{
}
else if (d == PortDevice.Printer)
{
}
else if (d == PortDevice.PPI)
{
PPI.WritePort(port, value);
}
else if (d == PortDevice.Expansion)
{
}
}
return;
}
/// <summary>
/// Writes a byte of data to a specified port address
/// Because of the port decoding, multiple devices can be written to
/// </summary>
/// <param name="port"></param>
/// <param name="value"></param>
public override void WritePort(ushort port, byte value)
{
BitArray portBits = new BitArray(BitConverter.GetBytes(port));
BitArray dataBits = new BitArray(BitConverter.GetBytes(value));
byte portUpper = (byte)(port >> 8);
byte portLower = (byte)(port & 0xff);
var devs = DecodeOUTPort(port);
foreach (var d in devs)
{
if (d == PortDevice.GateArray)
{
GateArray.WritePort(port, value);
}
else if (d == PortDevice.RAMManagement)
{
if (value.Bit(7) && value.Bit(6))
{
RAMConfig = value & 0x07;
// additional 64K bank index
var b64 = value & 0x38;
}
}
else if (d == PortDevice.CRCT)
{
CRCT.WritePort(port, value);
}
else if (d == PortDevice.ROMSelect)
{
UpperROMPosition = value;
}
else if (d == PortDevice.Printer)
{
}
else if (d == PortDevice.PPI)
{
PPI.WritePort(port, value);
}
else if (d == PortDevice.Expansion)
{
if (!port.Bit(7))
{
// FDC
if (port.Bit(8) && !port.Bit(0) || port.Bit(8) && port.Bit(0))
{
// FDC data register
UPDDiskDevice.WriteData(value);
}
if ((!port.Bit(8) && !port.Bit(0)) || (!port.Bit(8) && port.Bit(0)))
{
// FDC motor
UPDDiskDevice.Motor(value);
}
}
}
}
return;
}