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Implemented temporary "fake" display controller which renders Alto DCBs to the screen, bypassing the display microcode. Alto is booting! Rough keyboard implementation.

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This commit is contained in:
Josh Dersch
2015-11-11 16:34:44 -08:00
parent ca638f1d6e
commit 47a2ee4b2b
15 changed files with 690 additions and 199 deletions
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81
Contralto/Display/DisplayController.cs
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@@ -84,6 +84,28 @@ namespace Contralto.Display
_clocks++;
_totalClocks++;
//
// "If the DWT has not executed a BLOCK, if DHT is not blocked, and if the
// buffer is not full, DWT wakeups are generated."
//
if (_dataBuffer.Count < 16 &&
!_system.CPU.IsBlocked(TaskType.DisplayHorizontal) &&
!_dwtBlocked)
{
//Console.WriteLine("DWT wakeup, {0}", _dataBuffer.Count);
_system.CPU.WakeupTask(TaskType.DisplayWord);
}
else
{
// We can't take any words right now, remove Wakeup from
// the DWT.
if (_dataBuffer.Count >= 16)
{
//Log.Write(LogComponent.Display, "buffer full, blocking DWT.");
}
_system.CPU.BlockTask(TaskType.DisplayWord);
}
switch (_state)
{
case DisplayState.VerticalBlank:
@@ -98,44 +120,17 @@ namespace Contralto.Display
// Wake up DVT, DHT
_dwtBlocked = false;
_dhtBlocked = false;
_system.CPU.WakeupTask(TaskType.DisplayVertical);
_dhtBlocked = false;
_system.CPU.WakeupTask(TaskType.DisplayHorizontal);
_system.CPU.BlockTask(TaskType.DisplayWord);
// Run MRT
_system.CPU.WakeupTask(TaskType.MemoryRefresh);
// TODO: clear DWT, DHT block flip-flop
_state = DisplayState.VisibleScanline;
_system.CPU.BlockTask(TaskType.DisplayWord);
_state = DisplayState.HorizontalBlank;
//Console.WriteLine("Frame");
}
break;
case DisplayState.VisibleScanline:
//
// "If the DWT has not executed a BLOCK, if DHT is not blocked, and if the
// buffer is not full, DWT wakeups are generated."
//
if (_dataBuffer.Count < 16 &&
!_system.CPU.IsBlocked(TaskType.DisplayHorizontal) &&
!_dwtBlocked)
{
//Console.WriteLine("DWT wakeup, {0}", _dataBuffer.Count);
_system.CPU.WakeupTask(TaskType.DisplayWord);
}
else
{
// We can't take any words right now, remove Wakeup from
// the DWT.
if (_dataBuffer.Count >= 16)
{
//Log.Write(LogComponent.Display, "buffer full, blocking DWT.");
}
_system.CPU.BlockTask(TaskType.DisplayWord);
}
case DisplayState.VisibleScanline:
//
// A scanline is 38 words wide; we clock in each word
// from the buffer (if present).
@@ -151,7 +146,7 @@ namespace Contralto.Display
displayWord = _dataBuffer.Dequeue();
}
_display.DrawDisplayWord(_scanline, _word, displayWord);
//_display.DrawDisplayWord(_scanline, _word, displayWord);
_word++;
if (_word > 37)
@@ -165,7 +160,7 @@ namespace Contralto.Display
break;
case DisplayState.HorizontalBlank:
// Kill time until end of HBlank
// Kill time until end of HBlank
if (_clocks > _horizontalBlankClocks)
{
_clocks -= _horizontalBlankClocks;
@@ -180,11 +175,14 @@ namespace Contralto.Display
_state = DisplayState.VerticalBlank;
_evenField = !_evenField;
_system.CPU.BlockTask(TaskType.DisplayVertical);
// Wakeup DVT
_system.CPU.WakeupTask(TaskType.DisplayVertical);
// Block DHT
_system.CPU.BlockTask(TaskType.DisplayHorizontal);
_system.CPU.BlockTask(TaskType.DisplayWord);
_display.RefreshAltoDisplay();
//_display.RefreshAltoDisplay();
_frames++;
//Log.Write(LogComponent.Display, "Display field completed. {0} total clocks elapsed.", _totalClocks);
@@ -192,7 +190,10 @@ namespace Contralto.Display
}
else
{
_state = DisplayState.VisibleScanline;
_state = DisplayState.VisibleScanline;
// Run MRT
_system.CPU.WakeupTask(TaskType.MemoryRefresh);
}
}
break;
@@ -248,9 +249,9 @@ namespace Contralto.Display
// Timing constants
// 38uS per scanline; 4uS for hblank.
// ~35 scanlines for vblank (1330uS)
private const double _wordClocks = (34.0 / 38.0) / 0.17; // uSec to clocks
private const double _horizontalBlankClocks = 4.0 / 0.17;
private const double _verticalBlankClocks = 1333.0 / 0.17;
private const double _wordClocks = (34.0 / 38.0) / 0.017; // uSec to clocks
private const double _horizontalBlankClocks = 4.0 / 0.017;
private const double _verticalBlankClocks = 1333.0 / 0.017;
}