snes9xgx/source/snes9x/cpuexec.cpp

518 lines
14 KiB
C++

/**********************************************************************************
Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
(c) Copyright 1996 - 2002 Gary Henderson (gary.henderson@ntlworld.com) and
Jerremy Koot (jkoot@snes9x.com)
(c) Copyright 2002 - 2004 Matthew Kendora
(c) Copyright 2002 - 2005 Peter Bortas (peter@bortas.org)
(c) Copyright 2004 - 2005 Joel Yliluoma (http://iki.fi/bisqwit/)
(c) Copyright 2001 - 2006 John Weidman (jweidman@slip.net)
(c) Copyright 2002 - 2006 Brad Jorsch (anomie@users.sourceforge.net),
funkyass (funkyass@spam.shaw.ca),
Kris Bleakley (codeviolation@hotmail.com),
Nach (n-a-c-h@users.sourceforge.net), and
zones (kasumitokoduck@yahoo.com)
BS-X C emulator code
(c) Copyright 2005 - 2006 Dreamer Nom,
zones
C4 x86 assembler and some C emulation code
(c) Copyright 2000 - 2003 _Demo_ (_demo_@zsnes.com),
Nach,
zsKnight (zsknight@zsnes.com)
C4 C++ code
(c) Copyright 2003 - 2006 Brad Jorsch,
Nach
DSP-1 emulator code
(c) Copyright 1998 - 2006 _Demo_,
Andreas Naive (andreasnaive@gmail.com)
Gary Henderson,
Ivar (ivar@snes9x.com),
John Weidman,
Kris Bleakley,
Matthew Kendora,
Nach,
neviksti (neviksti@hotmail.com)
DSP-2 emulator code
(c) Copyright 2003 John Weidman,
Kris Bleakley,
Lord Nightmare (lord_nightmare@users.sourceforge.net),
Matthew Kendora,
neviksti
DSP-3 emulator code
(c) Copyright 2003 - 2006 John Weidman,
Kris Bleakley,
Lancer,
z80 gaiden
DSP-4 emulator code
(c) Copyright 2004 - 2006 Dreamer Nom,
John Weidman,
Kris Bleakley,
Nach,
z80 gaiden
OBC1 emulator code
(c) Copyright 2001 - 2004 zsKnight,
pagefault (pagefault@zsnes.com),
Kris Bleakley,
Ported from x86 assembler to C by sanmaiwashi
SPC7110 and RTC C++ emulator code
(c) Copyright 2002 Matthew Kendora with research by
zsKnight,
John Weidman,
Dark Force
S-DD1 C emulator code
(c) Copyright 2003 Brad Jorsch with research by
Andreas Naive,
John Weidman
S-RTC C emulator code
(c) Copyright 2001-2006 byuu,
John Weidman
ST010 C++ emulator code
(c) Copyright 2003 Feather,
John Weidman,
Kris Bleakley,
Matthew Kendora
Super FX x86 assembler emulator code
(c) Copyright 1998 - 2003 _Demo_,
pagefault,
zsKnight,
Super FX C emulator code
(c) Copyright 1997 - 1999 Ivar,
Gary Henderson,
John Weidman
Sound DSP emulator code is derived from SNEeSe and OpenSPC:
(c) Copyright 1998 - 2003 Brad Martin
(c) Copyright 1998 - 2006 Charles Bilyue'
SH assembler code partly based on x86 assembler code
(c) Copyright 2002 - 2004 Marcus Comstedt (marcus@mc.pp.se)
2xSaI filter
(c) Copyright 1999 - 2001 Derek Liauw Kie Fa
HQ2x filter
(c) Copyright 2003 Maxim Stepin (maxim@hiend3d.com)
Specific ports contains the works of other authors. See headers in
individual files.
Snes9x homepage: http://www.snes9x.com
Permission to use, copy, modify and/or distribute Snes9x in both binary
and source form, for non-commercial purposes, is hereby granted without
fee, providing that this license information and copyright notice appear
with all copies and any derived work.
This software is provided 'as-is', without any express or implied
warranty. In no event shall the authors be held liable for any damages
arising from the use of this software or it's derivatives.
Snes9x is freeware for PERSONAL USE only. Commercial users should
seek permission of the copyright holders first. Commercial use includes,
but is not limited to, charging money for Snes9x or software derived from
Snes9x, including Snes9x or derivatives in commercial game bundles, and/or
using Snes9x as a promotion for your commercial product.
The copyright holders request that bug fixes and improvements to the code
should be forwarded to them so everyone can benefit from the modifications
in future versions.
Super NES and Super Nintendo Entertainment System are trademarks of
Nintendo Co., Limited and its subsidiary companies.
**********************************************************************************/
#include "snes9x.h"
#include "memmap.h"
#include "cpuops.h"
#include "ppu.h"
#include "cpuexec.h"
#include "debug.h"
#include "snapshot.h"
#include "gfx.h"
#include "missing.h"
#include "apu.h"
#include "dma.h"
#include "sa1.h"
#include "spc7110.h"
#ifndef ZSNES_FX
#include "fxemu.h"
extern struct FxInit_s SuperFX;
#endif
void S9xMainLoop (void)
{
for (;;)
{
APU_EXECUTE();
if (CPU.Flags)
{
if (CPU.Flags & NMI_FLAG)
{
if (Timings.NMITriggerPos <= CPU.Cycles)
{
CPU.Flags &= ~NMI_FLAG;
Timings.NMITriggerPos = 0xffff;
if (CPU.WaitingForInterrupt)
{
CPU.WaitingForInterrupt = FALSE;
Registers.PCw++;
}
S9xOpcode_NMI();
}
}
#ifdef DEBUGGER
if ((CPU.Flags & BREAK_FLAG) && !(CPU.Flags & SINGLE_STEP_FLAG))
{
for (int Break = 0; Break != 6; Break++)
{
if (S9xBreakpoint[Break].Enabled &&
S9xBreakpoint[Break].Bank == Registers.PB &&
S9xBreakpoint[Break].Address == Registers.PCw)
{
if (S9xBreakpoint[Break].Enabled == 2)
S9xBreakpoint[Break].Enabled = TRUE;
else
CPU.Flags |= DEBUG_MODE_FLAG;
}
}
}
#endif
CHECK_SOUND();
if (CPU.Flags & IRQ_PENDING_FLAG)
{
if (CPU.WaitingForInterrupt)
{
CPU.WaitingForInterrupt = FALSE;
Registers.PCw++;
}
if (CPU.IRQActive && !Settings.DisableIRQ)
{
if (!CheckFlag(IRQ))
S9xOpcode_IRQ();
}
else
CPU.Flags &= ~IRQ_PENDING_FLAG;
}
if (CPU.Flags & SCAN_KEYS_FLAG)
break;
#ifdef DEBUGGER
if (CPU.Flags & DEBUG_MODE_FLAG)
break;
if (CPU.Flags & TRACE_FLAG)
S9xTrace();
if (CPU.Flags & SINGLE_STEP_FLAG)
{
CPU.Flags &= ~SINGLE_STEP_FLAG;
CPU.Flags |= DEBUG_MODE_FLAG;
}
#endif
}
#ifdef CPU_SHUTDOWN
CPU.PBPCAtOpcodeStart = Registers.PBPC;
#endif
register uint8 Op;
register struct SOpcodes *Opcodes;
if (CPU.PCBase)
{
Op = CPU.PCBase[Registers.PCw];
CPU.Cycles += CPU.MemSpeed;
Opcodes = ICPU.S9xOpcodes;
}
else
{
Op = S9xGetByte(Registers.PBPC);
OpenBus = Op;
Opcodes = S9xOpcodesSlow;
}
if ((Registers.PCw&MEMMAP_MASK) + ICPU.S9xOpLengths[Op] >= MEMMAP_BLOCK_SIZE)
{
uint8 *oldPCBase = CPU.PCBase;
CPU.PCBase = GetBasePointer(ICPU.ShiftedPB + ((uint16) (Registers.PCw + 4)));
if (oldPCBase!=CPU.PCBase || (Registers.PCw&~MEMMAP_MASK) == (0xffff & ~MEMMAP_MASK))
Opcodes = S9xOpcodesSlow;
}
Registers.PCw++;
(*Opcodes[Op].S9xOpcode)();
S9xUpdateAPUTimer();
if (SA1.Executing)
S9xSA1MainLoop();
if (CPU.Cycles >= CPU.NextEvent)
S9xDoHEventProcessing();
}
S9xPackStatus();
APURegisters.PC = IAPU.PC - IAPU.RAM;
S9xAPUPackStatus();
if (CPU.Flags & SCAN_KEYS_FLAG)
{
#ifdef DEBUGGER
if (!(CPU.Flags & FRAME_ADVANCE_FLAG))
#endif
S9xSyncSpeed();
CPU.Flags &= ~SCAN_KEYS_FLAG;
}
}
void S9xSetIRQ (uint32 source)
{
CPU.IRQActive |= source;
CPU.Flags |= IRQ_PENDING_FLAG;
if (CPU.WaitingForInterrupt)
{
// Force IRQ to trigger immediately after WAI -
// Final Fantasy Mystic Quest crashes without this.
CPU.WaitingForInterrupt = FALSE;
Registers.PCw++;
}
}
void S9xClearIRQ (uint32 source)
{
CLEAR_IRQ_SOURCE(source);
}
void S9xDoHEventProcessing (void)
{
#ifdef CPU_SHUTDOWN
CPU.WaitCounter++;
#endif
switch (CPU.WhichEvent)
{
case HC_HBLANK_START_EVENT:
S9xCheckMissingHTimerPosition(Timings.HBlankStart);
break;
case HC_HDMA_START_EVENT:
if (IPPU.HDMA && CPU.V_Counter <= PPU.ScreenHeight)
IPPU.HDMA = S9xDoHDMA(IPPU.HDMA);
S9xCheckMissingHTimerPosition(Timings.HDMAStart);
break;
case HC_HCOUNTER_MAX_EVENT:
#ifndef ZSNES_FX
if (Settings.SuperFX)
{
if (!SuperFX.oneLineDone)
S9xSuperFXExec();
SuperFX.oneLineDone = FALSE;
}
#else
S9xSuperFXExec();
#endif
#ifndef STORM
if (Settings.SoundSync)
S9xGenerateSound();
#endif
CPU.Cycles -= Timings.H_Max;
IAPU.NextAPUTimerPos -= (Timings.H_Max << SNES_APUTIMER_ACCURACY);
if (IAPU.APUExecuting)
APU.Cycles -= Timings.H_Max;
else
APU.Cycles = 0;
if ((Timings.NMITriggerPos != 0xffff) && (Timings.NMITriggerPos >= Timings.H_Max))
Timings.NMITriggerPos -= Timings.H_Max;
ICPU.Scanline++;
CPU.V_Counter++;
if (CPU.V_Counter >= Timings.V_Max) // V ranges from 0 to Timings.V_Max - 1
{
CPU.V_Counter = 0;
Timings.InterlaceField ^= 1;
// From byuu:
// [NTSC]
// interlace mode has 525 scanlines: 263 on the even frame, and 262 on the odd.
// non-interlace mode has 524 scanlines: 262 scanlines on both even and odd frames.
// [PAL] <PAL info is unverified on hardware>
// interlace mode has 625 scanlines: 313 on the even frame, and 312 on the odd.
// non-interlace mode has 624 scanlines: 312 scanlines on both even and odd frames.
if (IPPU.Interlace && !Timings.InterlaceField)
Timings.V_Max = Timings.V_Max_Master + 1; // 263 (NTSC), 313?(PAL)
else
Timings.V_Max = Timings.V_Max_Master; // 262 (NTSC), 312?(PAL)
Memory.FillRAM[0x213F] ^= 0x80;
PPU.RangeTimeOver = 0;
// FIXME: reading $4210 will wait 2 cycles, then perform reading, then wait 4 more cycles.
Memory.FillRAM[0x4210] = Model->_5A22;
CPU.Flags &= ~NMI_FLAG;
Timings.NMITriggerPos = 0xffff;
ICPU.Frame++;
PPU.HVBeamCounterLatched = 0;
CPU.Flags |= SCAN_KEYS_FLAG;
}
// From byuu:
// In non-interlace mode, there are 341 dots per scanline, and 262 scanlines per frame.
// On odd frames, scanline 240 is one dot short.
// In interlace mode, there are always 341 dots per scanline. Even frames have 263 scanlines,
// and odd frames have 262 scanlines.
// Interlace mode scanline 240 on odd frames is not missing a dot.
if (CPU.V_Counter == 240 && !IPPU.Interlace && Timings.InterlaceField) // V=240
Timings.H_Max = Timings.H_Max_Master - ONE_DOT_CYCLE; // HC=1360
else
Timings.H_Max = Timings.H_Max_Master; // HC=1364
if (Model->_5A22 == 2)
{
if (CPU.V_Counter != 240 || IPPU.Interlace || !Timings.InterlaceField) // V=240
{
if (Timings.WRAMRefreshPos == SNES_WRAM_REFRESH_HC_v2 - ONE_DOT_CYCLE) // HC=534
Timings.WRAMRefreshPos = SNES_WRAM_REFRESH_HC_v2; // HC=538
else
Timings.WRAMRefreshPos = SNES_WRAM_REFRESH_HC_v2 - ONE_DOT_CYCLE; // HC=534
}
}
else
Timings.WRAMRefreshPos = SNES_WRAM_REFRESH_HC_v1;
S9xCheckMissingHTimerPosition(0);
if (CPU.V_Counter == PPU.ScreenHeight + FIRST_VISIBLE_LINE) // VBlank starts from V=225(240).
{
S9xEndScreenRefresh();
IPPU.HDMA = 0;
// Bits 7 and 6 of $4212 are computed when read in S9xGetPPU.
#ifdef DEBUGGER
missing.dma_this_frame = 0;
#endif
IPPU.MaxBrightness = PPU.Brightness;
PPU.ForcedBlanking = (Memory.FillRAM [0x2100] >> 7) & 1;
if (!PPU.ForcedBlanking)
{
PPU.OAMAddr = PPU.SavedOAMAddr;
uint8 tmp = 0;
if (PPU.OAMPriorityRotation)
tmp = (PPU.OAMAddr & 0xFE) >> 1;
if ((PPU.OAMFlip & 1) || PPU.FirstSprite!=tmp)
{
PPU.FirstSprite = tmp;
IPPU.OBJChanged = TRUE;
}
PPU.OAMFlip = 0;
}
// FIXME: writing to $4210 will wait 6 cycles.
Memory.FillRAM[0x4210] = 0x80 | Model->_5A22;
if (Memory.FillRAM[0x4200] & 0x80)
{
// FIXME: triggered at HC=6, checked just before the final CPU cycle,
// then, when to call S9xOpcode_NMI()?
CPU.Flags |= NMI_FLAG;
Timings.NMITriggerPos = 6 + 6;
}
}
if (CPU.V_Counter == PPU.ScreenHeight + 3) // FIXME: not true
S9xDoAutoJoypad();
if (CPU.V_Counter == FIRST_VISIBLE_LINE) // V=1
S9xStartScreenRefresh();
CPU.NextEvent = -1;
break;
case HC_HDMA_INIT_EVENT:
if (CPU.V_Counter == 0)
S9xStartHDMA();
S9xCheckMissingHTimerPosition(Timings.HDMAInit);
break;
case HC_RENDER_EVENT:
if (CPU.V_Counter >= FIRST_VISIBLE_LINE && CPU.V_Counter <= PPU.ScreenHeight)
RenderLine(CPU.V_Counter - FIRST_VISIBLE_LINE);
S9xCheckMissingHTimerPosition(Timings.RenderPos);
break;
case HC_WRAM_REFRESH_EVENT:
if (!CPU.InDMA)
{
S9xCheckMissingHTimerPositionRange(Timings.WRAMRefreshPos, SNES_WRAM_REFRESH_CYCLES);
CPU.Cycles += SNES_WRAM_REFRESH_CYCLES;
S9xUpdateAPUTimer();
APU_EXECUTE();
}
else
S9xCheckMissingHTimerPosition(Timings.WRAMRefreshPos);
break;
case HC_IRQ_1_3_EVENT:
case HC_IRQ_3_5_EVENT:
case HC_IRQ_5_7_EVENT:
case HC_IRQ_7_9_EVENT:
case HC_IRQ_9_A_EVENT:
case HC_IRQ_A_1_EVENT:
if (PPU.HTimerEnabled && (!PPU.VTimerEnabled || (CPU.V_Counter == PPU.VTimerPosition)))
S9xSetIRQ(PPU_H_BEAM_IRQ_SOURCE);
else
if (PPU.VTimerEnabled && (CPU.V_Counter == PPU.VTimerPosition))
S9xSetIRQ(PPU_V_BEAM_IRQ_SOURCE);
break;
}
S9xReschedule();
}