From 2a5be0d42ca8b9e4f37ee591e2b70337c4a20b57 Mon Sep 17 00:00:00 2001
From: saxxonpike <saxxonpike@gmail.com>
Date: Mon, 12 Nov 2012 16:37:11 +0000
Subject: [PATCH] commodore64: rewrote cycle processing code, VIC should be
100% cycle accurate now. Also added preparation for PAL support
---
.../Computers/Commodore64/C64.PeekPoke.cs | 10 +-
.../Computers/Commodore64/C64.cs | 2 +-
.../Computers/Commodore64/MemBus.cs | 8 +-
.../Computers/Commodore64/VicII.cs | 531 ++++++++++++------
4 files changed, 379 insertions(+), 172 deletions(-)
diff --git a/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs b/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs
index ee90ce9fa1..0a46592896 100644
--- a/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/C64.PeekPoke.cs
@@ -9,12 +9,12 @@ namespace BizHawk.Emulation.Computers.Commodore64
{
public byte PeekCia0(int addr)
{
- return cia0.Peek(addr);
+ return cia0.regs[addr];
}
public byte PeekCia1(int addr)
{
- return cia1.Peek(addr);
+ return cia1.regs[addr];
}
public byte PeekColorRAM(int addr)
@@ -34,17 +34,17 @@ namespace BizHawk.Emulation.Computers.Commodore64
public byte PeekRAM(int addr)
{
- return mem.PeekRam(addr);
+ return mem.ram[addr];
}
public byte PeekSid(int addr)
{
- return sid.Peek(addr);
+ return sid.regs[addr];
}
public byte PeekVic(int addr)
{
- return vic.Peek(addr);
+ return vic.regs[addr];
}
public void PokeCia0(int addr, byte val)
diff --git a/BizHawk.Emulation/Computers/Commodore64/C64.cs b/BizHawk.Emulation/Computers/Commodore64/C64.cs
index 4f12476d51..b1c83681fa 100644
--- a/BizHawk.Emulation/Computers/Commodore64/C64.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/C64.cs
@@ -113,7 +113,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
private void SetupMemoryDomains()
{
var domains = new List<MemoryDomain>(1);
- domains.Add(new MemoryDomain("Memory", 0x10000, Endian.Little, new Func<int, byte>(PeekMemoryInt), new Action<int, byte>(PokeMemoryInt)));
+ domains.Add(new MemoryDomain("System Bus", 0x10000, Endian.Little, new Func<int, byte>(PeekMemoryInt), new Action<int, byte>(PokeMemoryInt)));
domains.Add(new MemoryDomain("RAM", 0x10000, Endian.Little, new Func<int, byte>(PeekRAM), new Action<int, byte>(PokeRAM)));
domains.Add(new MemoryDomain("CIA0", 0x10, Endian.Little, new Func<int, byte>(PeekCia0), new Action<int, byte>(PokeCia0)));
domains.Add(new MemoryDomain("CIA1", 0x10, Endian.Little, new Func<int, byte>(PeekCia1), new Action<int, byte>(PokeCia1)));
diff --git a/BizHawk.Emulation/Computers/Commodore64/MemBus.cs b/BizHawk.Emulation/Computers/Commodore64/MemBus.cs
index b58f79a774..7c129c5b1e 100644
--- a/BizHawk.Emulation/Computers/Commodore64/MemBus.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/MemBus.cs
@@ -219,19 +219,19 @@ namespace BizHawk.Emulation.Computers.Commodore64
result = charRom[addr & 0x0FFF];
break;
case MemoryDesignation.Vic:
- result = vic.regs[addr & 0x3F];
+ result = vic.Peek(addr & 0x3F);
break;
case MemoryDesignation.Sid:
- result = sid.regs[addr & 0x1F];
+ result = sid.Peek(addr & 0x1F);
break;
case MemoryDesignation.ColorRam:
result = (byte)(colorRam[addr & 0x03FF] | (busData & 0xF0));
break;
case MemoryDesignation.Cia0:
- result = cia0.regs[addr & 0x0F];
+ result = cia0.Peek(addr & 0x0F);
break;
case MemoryDesignation.Cia1:
- result = cia1.regs[addr & 0x0F];
+ result = cia1.Peek(addr & 0x0F);
break;
case MemoryDesignation.Expansion0:
result = 0;
diff --git a/BizHawk.Emulation/Computers/Commodore64/VicII.cs b/BizHawk.Emulation/Computers/Commodore64/VicII.cs
index f21a96bd12..9fad93ac9e 100644
--- a/BizHawk.Emulation/Computers/Commodore64/VicII.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/VicII.cs
@@ -518,6 +518,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
private Action FetchC;
private Action FetchG;
private Func<int> Plotter;
+ private Action PerformCycleFunction;
public VicII(ChipSignals newSignal, Region newRegion)
{
@@ -540,32 +541,13 @@ namespace BizHawk.Emulation.Computers.Commodore64
visibleWidth = 352;
visibleHeight = 232;
renderOffset = 0;
+ PerformCycleFunction = PerformCycleNTSC;
break;
case Region.PAL:
break;
default:
break;
}
-
- // initialize raster
- rasterWidth = totalCycles * 8;
- rasterOffsetX = rasterLineLeft;
- borderOnMain = true;
- borderOnVertical = true;
-
- // initialize buffer
- buffer = new int[visibleWidth * visibleHeight];
- bufferSize = buffer.Length;
-
- // initialize screen buffer
- characterMemory = new byte[40];
- colorMemory = new byte[40];
- pixelBuffer = new int[12];
- pixelBufferForeground = new bool[12];
- pixelBufferIndex = 0;
-
- // initialize registers
- spriteFetchIndex = 0;
HardReset();
}
@@ -642,15 +624,35 @@ namespace BizHawk.Emulation.Computers.Commodore64
public void HardReset()
{
+ // initialize raster
+ rasterWidth = totalCycles * 8;
+ rasterOffsetX = rasterLineLeft;
+ borderOnMain = true;
+ borderOnVertical = true;
+
+ // initialize buffer
+ buffer = new int[visibleWidth * visibleHeight];
+ bufferSize = buffer.Length;
+
+ // initialize screen buffer
+ characterMemory = new byte[40];
+ colorMemory = new byte[40];
+ pixelBuffer = new int[12];
+ pixelBufferForeground = new bool[12];
+ pixelBufferIndex = 0;
+
+ // initialize registers
+ spriteFetchIndex = 0;
idle = true;
refreshAddress = 0x3FFF;
regs = new VicIIRegs();
regs.RC = 7;
signal.VicAEC = true;
signal.VicIRQ = false;
+
+ // initialize screen
UpdateBorder();
UpdatePlotter();
- spriteFetchIndex = 17;
}
public byte Peek(int addr)
@@ -658,6 +660,14 @@ namespace BizHawk.Emulation.Computers.Commodore64
return regs[addr & 0x3F];
}
+ private void PerformBorderCheck()
+ {
+ if ((regs.RASTER == borderTop) && (regs.DEN))
+ borderOnVertical = false;
+ if (regs.RASTER == borderBottom)
+ borderOnVertical = true;
+ }
+
public void PerformCycle()
{
if (cycle >= totalCycles)
@@ -666,7 +676,8 @@ namespace BizHawk.Emulation.Computers.Commodore64
AdvanceRaster();
}
- ProcessDisplayRegisters();
+ PerformCycleCommon();
+ PerformCycleFunction();
RenderCycle();
// increment cycle
@@ -675,12 +686,8 @@ namespace BizHawk.Emulation.Computers.Commodore64
signal.VicIRQ = regs.IRQ;
}
- public void Poke(int addr, byte val)
- {
- regs[addr & 0x3F] = val;
- }
-
- private void ProcessDisplayRegisters()
+ // these operations are done every cycle
+ private void PerformCycleCommon()
{
// display enable check on line 030 (this must be run every cycle)
if (regs.RASTER == 0x030)
@@ -699,163 +706,363 @@ namespace BizHawk.Emulation.Computers.Commodore64
for (int i = 0; i < 8; i++)
if (!regs.MxYE[i])
regs.MYE[i] = true;
+ }
- // these actions are exclusive
- if ((regs.RASTER == 0x000 && cycle == 1) || (regs.RASTER > 0x000 && cycle == 0))
+ // operations timed to NTSC
+ private void PerformCycleNTSC()
+ {
+ switch (cycle)
{
- // IRQ is processed on cycle 1 of line 0 and cycle 0 on all other lines
- if (regs.RASTER == rasterInterruptLine)
- regs.IRST = true;
+ case 0:
+ // rasterline IRQ happens on cycle 1 on rasterline 0
+ if (regs.RASTER > 0 && regs.RASTER == rasterInterruptLine)
+ regs.IRST = true;
+ PerformSpritePointerFetch(3);
+ break;
+ case 1:
+ // rasterline IRQ happens on cycle 1 on rasterline 0
+ if (regs.RASTER == 0 && regs.RASTER == rasterInterruptLine)
+ regs.IRST = true;
+ PerformSpriteDataFetch(3);
+ break;
+ case 2:
+ PerformSpritePointerFetch(4);
+ break;
+ case 3:
+ PerformSpriteDataFetch(4);
+ break;
+ case 4:
+ PerformSpritePointerFetch(5);
+ break;
+ case 5:
+ PerformSpriteDataFetch(5);
+ break;
+ case 6:
+ PerformSpritePointerFetch(6);
+ break;
+ case 7:
+ PerformSpriteDataFetch(6);
+ break;
+ case 8:
+ PerformSpritePointerFetch(7);
+ break;
+ case 9:
+ PerformSpriteDataFetch(7);
+ break;
+ case 10:
+ PerformDRAMRefresh();
+ break;
+ case 11:
+ PerformDRAMRefresh();
+ break;
+ case 12:
+ PerformDRAMRefresh();
+ break;
+ case 13:
+ PerformVCReset();
+ PerformDRAMRefresh();
+ break;
+ case 14:
+ PerformDRAMRefresh();
+ break;
+ case 15:
+ PerformSpriteMCBASEAdvance();
+ PerformScreenCAccess();
+ break;
+ case 16:
+ PerformScreenCAccess();
+ break;
+ case 17:
+ PerformScreenCAccess();
+ break;
+ case 18:
+ PerformScreenCAccess();
+ break;
+ case 19:
+ PerformScreenCAccess();
+ break;
+ case 20:
+ PerformScreenCAccess();
+ break;
+ case 21:
+ PerformScreenCAccess();
+ break;
+ case 22:
+ PerformScreenCAccess();
+ break;
+ case 23:
+ PerformScreenCAccess();
+ break;
+ case 24:
+ PerformScreenCAccess();
+ break;
+ case 25:
+ PerformScreenCAccess();
+ break;
+ case 26:
+ PerformScreenCAccess();
+ break;
+ case 27:
+ PerformScreenCAccess();
+ break;
+ case 28:
+ PerformScreenCAccess();
+ break;
+ case 29:
+ PerformScreenCAccess();
+ break;
+ case 30:
+ PerformScreenCAccess();
+ break;
+ case 31:
+ PerformScreenCAccess();
+ break;
+ case 32:
+ PerformScreenCAccess();
+ break;
+ case 33:
+ PerformScreenCAccess();
+ break;
+ case 34:
+ PerformScreenCAccess();
+ break;
+ case 35:
+ PerformScreenCAccess();
+ break;
+ case 36:
+ PerformScreenCAccess();
+ break;
+ case 37:
+ PerformScreenCAccess();
+ break;
+ case 38:
+ PerformScreenCAccess();
+ break;
+ case 39:
+ PerformScreenCAccess();
+ break;
+ case 40:
+ PerformScreenCAccess();
+ break;
+ case 41:
+ PerformScreenCAccess();
+ break;
+ case 42:
+ PerformScreenCAccess();
+ break;
+ case 43:
+ PerformScreenCAccess();
+ break;
+ case 44:
+ PerformScreenCAccess();
+ break;
+ case 45:
+ PerformScreenCAccess();
+ break;
+ case 46:
+ PerformScreenCAccess();
+ break;
+ case 47:
+ PerformScreenCAccess();
+ break;
+ case 48:
+ PerformScreenCAccess();
+ break;
+ case 49:
+ PerformScreenCAccess();
+ break;
+ case 50:
+ PerformScreenCAccess();
+ break;
+ case 51:
+ PerformScreenCAccess();
+ break;
+ case 52:
+ PerformScreenCAccess();
+ break;
+ case 53:
+ PerformScreenCAccess();
+ break;
+ case 54:
+ PerformScreenCAccess();
+ PerformSpriteYExpansionFlip();
+ PerformSpriteComparison();
+ break;
+ case 55:
+ PerformSpriteComparison();
+ break;
+ case 56:
+ break;
+ case 57:
+ PerformSpriteDMAEnable();
+ PerformRCReset();
+ break;
+ case 58:
+ break;
+ case 59:
+ PerformSpritePointerFetch(0);
+ break;
+ case 60:
+ PerformSpriteDataFetch(0);
+ break;
+ case 61:
+ PerformSpritePointerFetch(1);
+ break;
+ case 62:
+ PerformSpriteDataFetch(1);
+ break;
+ case 63:
+ PerformSpritePointerFetch(2);
+ PerformBorderCheck();
+ break;
+ case 64:
+ PerformSpriteDataFetch(2);
+ break;
}
- else if (cycle >= 10 && cycle < 15)
- {
- // dram refresh
- mem.VicRead((ushort)refreshAddress);
- refreshAddress = (refreshAddress - 1) & 0xFF;
- refreshAddress |= 0x3F00;
+ }
- // VC reset
- if (cycle == 13)
+ // operations timed to PAL
+ private void PerformCyclePAL()
+ {
+ }
+
+ private void PerformDRAMRefresh()
+ {
+ // dram refresh
+ mem.VicRead((ushort)refreshAddress);
+ refreshAddress = (refreshAddress - 1) & 0xFF;
+ refreshAddress |= 0x3F00;
+ }
+
+ private void PerformRCReset()
+ {
+ // row counter processing
+ if (regs.RC == 7)
+ {
+ idle = true;
+ regs.VCBASE = regs.VC;
+ }
+ if (!idle)
+ regs.RC = (regs.RC + 1) & 0x07;
+ }
+
+ private void PerformScreenCAccess()
+ {
+ // screen memory c-access
+ if (badLine)
+ {
+ FetchC();
+ colorMemory[regs.VMLI] = colorDataBus;
+ characterMemory[regs.VMLI] = characterDataBus;
+ }
+ signal.VicAEC = !badLine;
+ }
+
+ private void PerformSpriteComparison()
+ {
+ // reenable cpu if disabled
+ signal.VicAEC = true;
+
+ // sprite comparison
+ for (int i = 0; i < 8; i++)
+ {
+ if (regs.MYE[i] && regs.MCBASE[i] == 63)
{
- regs.VC = regs.VCBASE;
- regs.VMLI = 0;
- characterColumn = 0;
- if (badLine)
- {
- regs.RC = 0;
- }
- bitmapData = 0;
- colorData = 0;
- characterData = 0;
+ regs.MD[i] = false;
+ regs.MDMA[i] = false;
}
- }
- else if (cycle >= 15 && cycle < 55)
- {
- // screen memory c-access
- if (badLine)
- {
- FetchC();
- colorMemory[regs.VMLI] = colorDataBus;
- characterMemory[regs.VMLI] = characterDataBus;
- }
- signal.VicAEC = !badLine;
- }
- else if (cycle == 55)
- {
- // reenable cpu if disabled
- signal.VicAEC = true;
- // sprite comparison
- for (int i = 0; i < 8; i++)
+ if (regs.MxE[i] == true && regs.MxY[i] == (regs.RASTER & 0xFF) && regs.MDMA[i] == false)
{
- if (regs.MYE[i] && regs.MCBASE[i] == 63)
- {
- regs.MD[i] = false;
- regs.MDMA[i] = false;
- }
-
+ regs.MDMA[i] = true;
+ regs.MCBASE[i] = 0;
if (regs.MxYE[i])
- regs.MYE[i] = !regs.MYE[i];
+ regs.MYE[i] = false;
+ }
+ }
+ }
- if (regs.MxE[i] == true && regs.MxY[i] == (regs.RASTER & 0xFF) && regs.MDMA[i] == false)
+ private void PerformSpriteDataFetch(int spriteIndex)
+ {
+ // second half of the fetch cycle
+ signal.VicAEC = !regs.MDMA[spriteIndex];
+ if (regs.MDMA[spriteIndex])
+ {
+ for (int i = 0; i < 2; i++)
+ {
+ regs.MSR[spriteIndex] <<= 8;
+ regs.MSR[spriteIndex] |= mem.VicRead((ushort)((regs.MPTR[spriteIndex] << 6) | (regs.MC[spriteIndex])));
+ regs.MC[spriteIndex]++;
+ }
+ }
+ }
+
+ private void PerformSpriteDMAEnable()
+ {
+ // sprite MC processing
+ for (int i = 0; i < 8; i++)
+ {
+ regs.MC[i] = regs.MCBASE[i];
+ if (regs.MDMA[i] && regs.MxY[i] == (regs.RASTER & 0xFF))
+ regs.MD[i] = true;
+ }
+ }
+
+ private void PerformSpriteMCBASEAdvance()
+ {
+ for (int i = 0; i < 8; i++)
+ {
+ if (regs.MYE[i])
+ {
+ if (regs.MD[i])
{
- regs.MDMA[i] = true;
- regs.MCBASE[i] = 0;
- if (regs.MxYE[i])
- regs.MYE[i] = false;
+ regs.MCBASE[i] += 3;
}
}
}
- else if (cycle == 57)
- {
- // row counter processing
- if (regs.RC == 7)
- {
- idle = true;
- regs.VCBASE = regs.VC;
- }
- if (!idle)
- regs.RC = (regs.RC + 1) & 0x07;
+ }
- // sprite MC processing
- for (int i = 0; i < 8; i++)
- {
- regs.MC[i] = regs.MCBASE[i];
- if (regs.MDMA[i] && regs.MxY[i] == (regs.RASTER & 0xFF))
- regs.MD[i] = true;
- }
- }
+ private void PerformSpritePointerFetch(int spriteIndex)
+ {
+ // first half of the fetch cycle, always fetch pointer
+ ushort pointerOffset = (ushort)((regs.VM << 10) | 0x3F8 | spriteIndex);
+ regs.MPTR[spriteIndex] = mem.VicRead(pointerOffset);
- // MCBASE reset if applicable
- if (cycle == 15)
+ // also fetch upper 8 bits if enabled
+ signal.VicAEC = !regs.MDMA[spriteIndex];
+ if (regs.MDMA[spriteIndex])
{
- for (int i = 0; i < 8; i++)
- {
- if (regs.MYE[i])
- {
- if (regs.MD[i])
- {
- regs.MCBASE[i] += 3;
- }
- }
- }
+ regs.MSRC[spriteIndex] = 24;
+ regs.MSR[spriteIndex] = mem.VicRead((ushort)((regs.MPTR[spriteIndex] << 6) | (regs.MC[spriteIndex])));
+ regs.MC[spriteIndex]++;
}
+ }
- // sprite fetch
- if (cycle == spriteFetchStartCycle)
- {
- spriteFetchIndex = 0;
- }
- if (spriteFetchIndex < 16)
- {
- int spriteIndex = spriteFetchIndex >> 1;
+ private void PerformSpriteYExpansionFlip()
+ {
+ for (int i = 0; i < 8; i++)
+ if (regs.MxYE[i])
+ regs.MYE[i] = !regs.MYE[i];
+ }
- if ((spriteFetchIndex & 1) == 0)
- {
- // first half of the fetch cycle, always fetch pointer
- ushort pointerOffset = (ushort)((regs.VM << 10) | 0x3F8 | spriteIndex);
- regs.MPTR[spriteIndex] = mem.VicRead(pointerOffset);
-
- // also fetch upper 8 bits if enabled
- signal.VicAEC = !regs.MDMA[spriteIndex];
- if (regs.MDMA[spriteIndex])
- {
- regs.MSRC[spriteIndex] = 24;
- regs.MSR[spriteIndex] = mem.VicRead((ushort)((regs.MPTR[spriteIndex] << 6) | (regs.MC[spriteIndex])));
- regs.MC[spriteIndex]++;
- }
- }
- else
- {
- // second half of the fetch cycle
- signal.VicAEC = !regs.MDMA[spriteIndex];
- if (regs.MDMA[spriteIndex])
- {
- for (int i = 0; i < 2; i++)
- {
- regs.MSR[spriteIndex] <<= 8;
- regs.MSR[spriteIndex] |= mem.VicRead((ushort)((regs.MPTR[spriteIndex] << 6) | (regs.MC[spriteIndex])));
- regs.MC[spriteIndex]++;
- }
- }
- }
- spriteFetchIndex++;
- }
- else if (spriteFetchIndex == 16)
+ private void PerformVCReset()
+ {
+ // VC reset
+ regs.VC = regs.VCBASE;
+ regs.VMLI = 0;
+ characterColumn = 0;
+ if (badLine)
{
- // set AEC after sprite fetches
- signal.VicAEC = true;
- spriteFetchIndex++;
+ regs.RC = 0;
}
+ bitmapData = 0;
+ colorData = 0;
+ characterData = 0;
+ }
- // border check
- if (cycle == 63)
- {
- if ((regs.RASTER == borderTop) && (regs.DEN))
- borderOnVertical = false;
- if (regs.RASTER == borderBottom)
- borderOnVertical = true;
- }
+ public void Poke(int addr, byte val)
+ {
+ regs[addr & 0x3F] = val;
}
// standard text mode