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Merge branch 'master' of https://github.com/MoleskiCoder/EightBitNet

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This commit is contained in:
Adrian Conlon 2019-11-30 14:06:48 +00:00
commit e98f841e9f
1 changed files with 16 additions and 22 deletions
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38
LR35902/Bus.cs
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@ -38,6 +38,8 @@ namespace EightBit.GameBoy
private int romBank = 1; private int romBank = 1;
private int ramBank = 0; private int ramBank = 0;
private int allowed = 0;
protected Bus() protected Bus()
{ {
this.IO = new IoRegisters(this); this.IO = new IoRegisters(this);
@ -98,17 +100,17 @@ namespace EightBit.GameBoy
this.ValidateCartridgeType(); this.ValidateCartridgeType();
} }
public int RunRasterLines() public void RunRasterLines()
{ {
this.enabledLCD = (this.IO.Peek(IoRegisters.LCDC) & (byte)LcdcControl.LcdEnable) != 0; this.enabledLCD = (this.IO.Peek(IoRegisters.LCDC) & (byte)LcdcControl.LcdEnable) != 0;
this.IO.ResetLY(); this.IO.ResetLY();
return this.RunRasterLines(DisplayCharacteristics.RasterHeight); this.RunRasterLines(DisplayCharacteristics.RasterHeight);
} }
public int RunVerticalBlankLines() public void RunVerticalBlankLines()
{ {
var lines = TotalLineCount - DisplayCharacteristics.RasterHeight; var lines = TotalLineCount - DisplayCharacteristics.RasterHeight;
return this.RunVerticalBlankLines(lines); this.RunVerticalBlankLines(lines);
} }
public override MemoryMapping Mapping(ushort address) public override MemoryMapping Mapping(ushort address)
@ -322,21 +324,15 @@ namespace EightBit.GameBoy
} }
} }
private int RunRasterLines(int lines) private void RunRasterLines(int lines)
{ {
var count = 0;
var allowed = CyclesPerLine;
for (var line = 0; line < lines; ++line) for (var line = 0; line < lines; ++line)
{ {
var executed = this.RunRasterLine(allowed); this.RunRasterLine(CyclesPerLine);
count += executed;
allowed = CyclesPerLine - (executed - CyclesPerLine);
} }
return count;
} }
private int RunVerticalBlankLines(int lines) private void RunVerticalBlankLines(int lines)
{ {
/* /*
Vertical Blank interrupt is triggered when the LCD Vertical Blank interrupt is triggered when the LCD
@ -365,10 +361,10 @@ namespace EightBit.GameBoy
this.IO.TriggerInterrupt(Interrupts.VerticalBlank); this.IO.TriggerInterrupt(Interrupts.VerticalBlank);
} }
return this.RunRasterLines(lines); this.RunRasterLines(lines);
} }
private int RunRasterLine(int limit) private void RunRasterLine(int suggested)
{ {
/* /*
A scanline normally takes 456 clocks (912 clocks in double speed A scanline normally takes 456 clocks (912 clocks in double speed
@ -393,7 +389,7 @@ namespace EightBit.GameBoy
The rest of the clocks of line 153 are spent in line 0 in mode 1! The rest of the clocks of line 153 are spent in line 0 in mode 1!
*/ */
var count = 0; this.allowed += suggested;
if (this.enabledLCD) if (this.enabledLCD)
{ {
if (((this.IO.Peek(IoRegisters.STAT) & (byte)Bits.Bit6) != 0) && (this.IO.Peek(IoRegisters.LYC) == this.IO.Peek(IoRegisters.LY))) if (((this.IO.Peek(IoRegisters.STAT) & (byte)Bits.Bit6) != 0) && (this.IO.Peek(IoRegisters.LYC) == this.IO.Peek(IoRegisters.LY)))
@ -408,11 +404,11 @@ namespace EightBit.GameBoy
this.IO.TriggerInterrupt(Interrupts.DisplayControlStatus); this.IO.TriggerInterrupt(Interrupts.DisplayControlStatus);
} }
count += this.CPU.Run(80); // ~19us this.allowed -= this.CPU.Run(80); // ~19us
// Mode 3, OAM/VRAM unavailable // Mode 3, OAM/VRAM unavailable
this.IO.UpdateLcdStatusMode(LcdStatusMode.TransferringDataToLcd); this.IO.UpdateLcdStatusMode(LcdStatusMode.TransferringDataToLcd);
count += this.CPU.Run(170); // ~41us this.allowed -= this.CPU.Run(170); // ~41us
// Mode 0 // Mode 0
this.IO.UpdateLcdStatusMode(LcdStatusMode.HBlank); this.IO.UpdateLcdStatusMode(LcdStatusMode.HBlank);
@ -421,16 +417,14 @@ namespace EightBit.GameBoy
this.IO.TriggerInterrupt(Interrupts.DisplayControlStatus); this.IO.TriggerInterrupt(Interrupts.DisplayControlStatus);
} }
count += this.CPU.Run(limit - count); // ~48.6us this.allowed -= this.CPU.Run(this.allowed); // ~48.6us
this.IO.IncrementLY(); this.IO.IncrementLY();
} }
else else
{ {
count += this.CPU.Run(CyclesPerLine); this.allowed -= this.CPU.Run(this.allowed);
} }
return count;
} }
} }
} }