private void Mask(byte irq)
{
DebugStub.Assert(Processor.InterruptsDisabled());
ushort newMask = (ushort)(irqMask | (1 << irq));
if (newMask != irqMask)
{
#if DEBUG_DISPATCH_IO
DebugStub.WriteLine("-- Mask IRQs: old={0:x4} new={1:x4}",
__arglist(irqMask, newMask));
#endif
irqMask = newMask;
IoResult result;
result = pic1MaskPort.Write8NoThrow((byte)(irqMask >> 8));
DebugStub.Assert(IoResult.Success == result);
result = pic0MaskPort.Write8NoThrow((byte)(irqMask & 0xff));
DebugStub.Assert(IoResult.Success == result);
#if PIC_DEBUG
byte mask0;
pic0MaskPort.Read8NoThrow(out mask0);
byte mask1;
pic1MaskPort.Read8NoThrow(out mask1);
DebugStub.Print("PIC Mask: {0:x2}{1:x2}\n",
__arglist(mask1, mask0));
#endif
}
}
internal void PitWrite(int pt)
{
#if TIMER_NO_GO
return;
#endif // TIMER_NO_GO
IoResult result;
result = CWPort.Write8NoThrow(i8254_CW_MODE0 | i8254_CW_BOTH | i8254_CW_SEL0);
DebugStub.Assert(IoResult.Success == result);
result = C0Port.Write8NoThrow((byte)(pt & 0xff));
DebugStub.Assert(IoResult.Success == result);
result = C0Port.Write8NoThrow((byte)(pt >> 8));
DebugStub.Assert(IoResult.Success == result);
byte v;
do
{
result = CWPort.Write8NoThrow(i8254_RB_NOCOUNT | i8254_RB_SEL0);
DebugStub.Assert(IoResult.Success == result);
result = C0Port.Read8NoThrow(out v);
DebugStub.Assert(IoResult.Success == result);
} while ((v & i8254_RB_NULL) == i8254_RB_NULL);
}
public override void AckIrq(byte irq)
{
DebugStub.Assert(Processor.InterruptsDisabled());
#if PIC_DEBUG
DumpRegisters();
#endif
// Mark the IRQ as activated and mask it
#if DEBUG_INTERRUPTS
DebugStub.Print("Int{0:x2} Acked, Mask={1:x4}\n",
__arglist(irq + baseVector, irqMask));
#endif
// Quite the interrupt controller.
IoResult result;
if (irq >= 8)
{
result = pic1CtrlPort.Write8NoThrow(PIC_NS_EOI);
DebugStub.Assert(IoResult.Success == result);
}
result = pic0CtrlPort.Write8NoThrow(PIC_NS_EOI);
DebugStub.Assert(IoResult.Success == result);
#if PIC_DEBUG
DumpRegisters();
#endif
}
private void UpdateCursor(bool newVisibleState)
{
IoResult result;
if (newVisibleState != cursorVisible)
{
byte cgaStart = 32; // Cursor off
if (newVisibleState)
{
cgaStart = (byte)(64 + cursorStartLine); // Cursor on
}
result = indexRegister.Write8NoThrow(CGA_CURSOR_START);
DebugStub.Assert(IoResult.Success == result);
result = dataRegister.Write8NoThrow(cgaStart);
DebugStub.Assert(IoResult.Success == result);
cursorVisible = newVisibleState;
}
if (newVisibleState)
{
// Write cursor location
result = indexRegister.Write8NoThrow(CGA_CURSOR_MSB);
DebugStub.Assert(IoResult.Success == result);
result = dataRegister.Write8NoThrow((byte)(cursor >> 8));
DebugStub.Assert(IoResult.Success == result);
result = indexRegister.Write8NoThrow(CGA_CURSOR_LSB);
DebugStub.Assert(IoResult.Success == result);
result = dataRegister.Write8NoThrow((byte)(cursor & 0xff));
DebugStub.Assert(IoResult.Success == result);
}
}
private byte ReadRtc(byte addr)
{
IoResult result;
result = rtcadd.Write8NoThrow(addr);
DebugStub.Assert(IoResult.Success == result);
byte value;
result = rtcdat.Read8NoThrow(out value);
DebugStub.Assert(IoResult.Success == result);
return value;
}
private void WriteRtc(byte addr, byte val)
{
IoResult result;
result = rtcadd.Write8NoThrow(addr);
DebugStub.Assert(IoResult.Success == result);
result = rtcdat.Write8NoThrow(val);
DebugStub.Assert(IoResult.Success == result);
}
public void AckIrq(byte irq)
{
DumpRegisters();
#if DEBUG_INTERRUPTS
DebugStub.Print("Int{0:x2} Acked, Mask={1:x8}\n",
__arglist(irq + baseVector, irqMask));
#endif
// Quiet the interrupt controller.
IoResult result;
if (irq >= 8)
{
result = pic1CtrlPort.Write8NoThrow(0x20);
DebugStub.Assert(IoResult.Success == result);
}
result = pic0CtrlPort.Write8NoThrow(0x20);
DebugStub.Assert(IoResult.Success == result);
DumpRegisters();
}