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authoraliaspider2014-10-29 05:36:07 +0100
committeraliaspider2014-10-29 05:36:07 +0100
commita6dc7abc9b8cc3986eda5a84141da7dc9e4e8f1a (patch)
tree6f82417b0ab41f3887dd025ee3b85254e28143da /source/cpuexec.c
parent1d98e1c317fa19687ae6bc3cb8e550ef7531bf02 (diff)
downloadsnes9x2005-a6dc7abc9b8cc3986eda5a84141da7dc9e4e8f1a.tar.gz
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start moving everything to C
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diff --git a/source/cpuexec.c b/source/cpuexec.c
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+/*******************************************************************************
+ 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 2001 - 2004 John Weidman (jweidman@slip.net)
+
+ (c) Copyright 2002 - 2004 Brad Jorsch (anomie@users.sourceforge.net),
+ funkyass (funkyass@spam.shaw.ca),
+ Joel Yliluoma (http://iki.fi/bisqwit/)
+ Kris Bleakley (codeviolation@hotmail.com),
+ Matthew Kendora,
+ Nach (n-a-c-h@users.sourceforge.net),
+ Peter Bortas (peter@bortas.org) and
+ zones (kasumitokoduck@yahoo.com)
+
+ C4 x86 assembler and some C emulation code
+ (c) Copyright 2000 - 2003 zsKnight (zsknight@zsnes.com),
+ _Demo_ (_demo_@zsnes.com), and Nach
+
+ C4 C++ code
+ (c) Copyright 2003 Brad Jorsch
+
+ DSP-1 emulator code
+ (c) Copyright 1998 - 2004 Ivar (ivar@snes9x.com), _Demo_, Gary Henderson,
+ John Weidman, neviksti (neviksti@hotmail.com),
+ Kris Bleakley, Andreas Naive
+
+ DSP-2 emulator code
+ (c) Copyright 2003 Kris Bleakley, John Weidman, neviksti, Matthew Kendora, and
+ Lord Nightmare (lord_nightmare@users.sourceforge.net
+
+ OBC1 emulator code
+ (c) Copyright 2001 - 2004 zsKnight, pagefault (pagefault@zsnes.com) and
+ 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, and Dark Force
+
+ S-DD1 C emulator code
+ (c) Copyright 2003 Brad Jorsch with research by
+ Andreas Naive and John Weidman
+
+ S-RTC C emulator code
+ (c) Copyright 2001 John Weidman
+
+ ST010 C++ emulator code
+ (c) Copyright 2003 Feather, Kris Bleakley, John Weidman and Matthew Kendora
+
+ Super FX x86 assembler emulator code
+ (c) Copyright 1998 - 2003 zsKnight, _Demo_, and pagefault
+
+ Super FX C emulator code
+ (c) Copyright 1997 - 1999 Ivar, Gary Henderson and John Weidman
+
+
+ SH assembler code partly based on x86 assembler code
+ (c) Copyright 2002 - 2004 Marcus Comstedt (marcus@mc.pp.se)
+
+
+ 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 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.
+
+ Snes9x is freeware for PERSONAL USE only. Commercial users should
+ seek permission of the copyright holders first. Commercial use includes
+ charging money for Snes9x or software derived from Snes9x.
+
+ 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 "ds2_timer.h"
+//#include "ds2_cpu.h"
+//#include "ds2io.h"
+
+#include "snes9x.h"
+#include "memmap.h"
+#include "cpuops.h"
+#include "ppu.h"
+#include "cpuexec.h"
+#include "snapshot.h"
+#include "gfx.h"
+#include "missing.h"
+#include "apu.h"
+#include "dma.h"
+#include "fxemu.h"
+#include "sa1.h"
+#include "spc7110.h"
+
+#ifdef ACCUMULATE_JOYPAD
+#include "display.h"
+#endif
+
+extern void S9xProcessSound (unsigned int);
+
+void S9xMainLoop_SA1_SFX (void);
+void S9xMainLoop_SA1_NoSFX (void);
+void S9xMainLoop_NoSA1_SFX (void);
+void S9xMainLoop_NoSA1_NoSFX (void);
+
+/*
+ * This is a CATSFC modification inspired by a Snes9x-Euphoria modification.
+ * The emulator selects a main loop based on the chips used in an entire
+ * frame. This avoids the constant SA1.Executing and Settings.SuperFX checks.
+ *
+ * The original version of S9xMainLoop is S9xMainLoop_SA1_SFX below. Remember
+ * to propagate modifications to the SA1_NoSFX, NoSA1_SFX and NoSA1_NoSFX
+ * versions.
+ */
+void S9xMainLoop (void)
+{
+ if (Settings.SA1)
+ {
+ if (Settings.SuperFX) S9xMainLoop_SA1_SFX ();
+ else /* if (!Settings.SuperFX) */ S9xMainLoop_SA1_NoSFX ();
+ }
+ else /* if (!Settings.SA1) */
+ {
+ if (Settings.SuperFX) S9xMainLoop_NoSA1_SFX ();
+ else /* if (!Settings.SuperFX) */ S9xMainLoop_NoSA1_NoSFX ();
+ }
+}
+
+void S9xMainLoop_SA1_SFX (void)
+{
+ for (;;)
+ {
+ APU_EXECUTE ();
+
+ if (CPU.Flags)
+ {
+ if (CPU.Flags & NMI_FLAG)
+ {
+ if (--CPU.NMICycleCount == 0) {
+ CPU.Flags &= ~NMI_FLAG;
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ S9xOpcode_NMI ();
+ }
+ }
+
+ CHECK_SOUND ();
+
+ if (CPU.Flags & IRQ_PENDING_FLAG)
+ {
+ if (CPU.IRQCycleCount == 0)
+ {
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ if (CPU.IRQActive && !Settings.DisableIRQ) {
+ if (!CheckFlag (IRQ))
+ S9xOpcode_IRQ ();
+ }
+ else
+ CPU.Flags &= ~IRQ_PENDING_FLAG;
+ }
+ else
+ {
+ if(--CPU.IRQCycleCount==0 && CheckFlag (IRQ))
+ CPU.IRQCycleCount=1;
+ }
+ }
+
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ break;
+ }
+
+#ifdef CPU_SHUTDOWN
+ CPU.PCAtOpcodeStart = CPU.PC;
+#endif
+ CPU.Cycles += CPU.MemSpeed;
+
+ (*ICPU.S9xOpcodes [*CPU.PC++].S9xOpcode) ();
+
+ if (SA1.Executing)
+ S9xSA1MainLoop ();
+ DO_HBLANK_CHECK_SFX();
+ }
+
+ ICPU.Registers.PC = CPU.PC - CPU.PCBase;
+ S9xPackStatus ();
+ IAPU.Registers.PC = IAPU.PC - IAPU.RAM;
+ S9xAPUPackStatus ();
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ {
+ S9xSyncSpeed ();
+ CPU.Flags &= ~SCAN_KEYS_FLAG;
+ }
+
+#ifdef DETECT_NASTY_FX_INTERLEAVE
+ if (CPU.BRKTriggered && Settings.SuperFX && !CPU.TriedInterleavedMode2)
+ {
+ CPU.TriedInterleavedMode2 = TRUE;
+ CPU.BRKTriggered = FALSE;
+ S9xDeinterleaveMode2 ();
+ }
+#endif
+}
+
+void S9xMainLoop_SA1_NoSFX (void)
+{
+ for (;;)
+ {
+ APU_EXECUTE ();
+
+ if (CPU.Flags)
+ {
+ if (CPU.Flags & NMI_FLAG)
+ {
+ if (--CPU.NMICycleCount == 0) {
+ CPU.Flags &= ~NMI_FLAG;
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ S9xOpcode_NMI ();
+ }
+ }
+
+ CHECK_SOUND ();
+
+ if (CPU.Flags & IRQ_PENDING_FLAG)
+ {
+ if (CPU.IRQCycleCount == 0)
+ {
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ if (CPU.IRQActive && !Settings.DisableIRQ) {
+ if (!CheckFlag (IRQ))
+ S9xOpcode_IRQ ();
+ }
+ else
+ CPU.Flags &= ~IRQ_PENDING_FLAG;
+ }
+ else
+ {
+ if(--CPU.IRQCycleCount==0 && CheckFlag (IRQ))
+ CPU.IRQCycleCount=1;
+ }
+ }
+
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ break;
+ }
+
+#ifdef CPU_SHUTDOWN
+ CPU.PCAtOpcodeStart = CPU.PC;
+#endif
+ CPU.Cycles += CPU.MemSpeed;
+
+ (*ICPU.S9xOpcodes [*CPU.PC++].S9xOpcode) ();
+
+ if (SA1.Executing)
+ S9xSA1MainLoop ();
+ DO_HBLANK_CHECK_NoSFX();
+ }
+
+ ICPU.Registers.PC = CPU.PC - CPU.PCBase;
+ S9xPackStatus ();
+ IAPU.Registers.PC = IAPU.PC - IAPU.RAM;
+ S9xAPUPackStatus ();
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ {
+ S9xSyncSpeed ();
+ CPU.Flags &= ~SCAN_KEYS_FLAG;
+ }
+}
+
+void S9xMainLoop_NoSA1_SFX (void)
+{
+ for (;;)
+ {
+ APU_EXECUTE ();
+
+ if (CPU.Flags)
+ {
+ if (CPU.Flags & NMI_FLAG)
+ {
+ if (--CPU.NMICycleCount == 0) {
+ CPU.Flags &= ~NMI_FLAG;
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ S9xOpcode_NMI ();
+ }
+ }
+
+ CHECK_SOUND ();
+
+ if (CPU.Flags & IRQ_PENDING_FLAG)
+ {
+ if (CPU.IRQCycleCount == 0)
+ {
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ if (CPU.IRQActive && !Settings.DisableIRQ) {
+ if (!CheckFlag (IRQ))
+ S9xOpcode_IRQ ();
+ }
+ else
+ CPU.Flags &= ~IRQ_PENDING_FLAG;
+ }
+ else
+ {
+ if(--CPU.IRQCycleCount==0 && CheckFlag (IRQ))
+ CPU.IRQCycleCount=1;
+ }
+ }
+
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ break;
+ }
+
+#ifdef CPU_SHUTDOWN
+ CPU.PCAtOpcodeStart = CPU.PC;
+#endif
+ CPU.Cycles += CPU.MemSpeed;
+
+ (*ICPU.S9xOpcodes [*CPU.PC++].S9xOpcode) ();
+
+ DO_HBLANK_CHECK_SFX();
+ }
+
+ ICPU.Registers.PC = CPU.PC - CPU.PCBase;
+ S9xPackStatus ();
+ IAPU.Registers.PC = IAPU.PC - IAPU.RAM;
+ S9xAPUPackStatus ();
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ {
+ S9xSyncSpeed ();
+ CPU.Flags &= ~SCAN_KEYS_FLAG;
+ }
+
+#ifdef DETECT_NASTY_FX_INTERLEAVE
+ if (CPU.BRKTriggered && Settings.SuperFX && !CPU.TriedInterleavedMode2)
+ {
+ CPU.TriedInterleavedMode2 = TRUE;
+ CPU.BRKTriggered = FALSE;
+ S9xDeinterleaveMode2 ();
+ }
+#endif
+}
+
+void S9xMainLoop_NoSA1_NoSFX (void)
+{
+ for (;;)
+ {
+ APU_EXECUTE ();
+
+ if (CPU.Flags)
+ {
+ if (CPU.Flags & NMI_FLAG)
+ {
+ if (--CPU.NMICycleCount == 0) {
+ CPU.Flags &= ~NMI_FLAG;
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ S9xOpcode_NMI ();
+ }
+ }
+
+ CHECK_SOUND ();
+
+ if (CPU.Flags & IRQ_PENDING_FLAG)
+ {
+ if (CPU.IRQCycleCount == 0)
+ {
+ if (CPU.WaitingForInterrupt) {
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+ if (CPU.IRQActive && !Settings.DisableIRQ) {
+ if (!CheckFlag (IRQ))
+ S9xOpcode_IRQ ();
+ }
+ else
+ CPU.Flags &= ~IRQ_PENDING_FLAG;
+ }
+ else
+ {
+ if(--CPU.IRQCycleCount==0 && CheckFlag (IRQ))
+ CPU.IRQCycleCount=1;
+ }
+ }
+
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ break;
+ }
+
+#ifdef CPU_SHUTDOWN
+ CPU.PCAtOpcodeStart = CPU.PC;
+#endif
+ CPU.Cycles += CPU.MemSpeed;
+
+ (*ICPU.S9xOpcodes [*CPU.PC++].S9xOpcode) ();
+
+ DO_HBLANK_CHECK_NoSFX();
+ }
+
+ ICPU.Registers.PC = CPU.PC - CPU.PCBase;
+ S9xPackStatus ();
+ IAPU.Registers.PC = IAPU.PC - IAPU.RAM;
+ S9xAPUPackStatus ();
+ if (CPU.Flags & SCAN_KEYS_FLAG)
+ {
+ S9xSyncSpeed ();
+ CPU.Flags &= ~SCAN_KEYS_FLAG;
+ }
+}
+
+void S9xSetIRQ (uint32 source)
+{
+ CPU.IRQActive |= source;
+ CPU.Flags |= IRQ_PENDING_FLAG;
+ CPU.IRQCycleCount = 3;
+ if (CPU.WaitingForInterrupt)
+ {
+ // Force IRQ to trigger immediately after WAI -
+ // Final Fantasy Mystic Quest crashes without this.
+ CPU.IRQCycleCount = 0;
+ CPU.WaitingForInterrupt = FALSE;
+ CPU.PC++;
+ }
+}
+
+void S9xClearIRQ (uint32 source)
+{
+ CLEAR_IRQ_SOURCE (source);
+}
+
+/*
+ * This is a CATSFC modification inspired by a Snes9x-Euphoria modification.
+ * The emulator selects an HBlank processor based on the chips used in an
+ * entire frame. This avoids the constant Settings.SuperFX checks.
+ *
+ * The original version of S9xDoHBlankProcessing is S9xDoHBlankProcessing_SFX
+ * below. Remember to propagate modifications to the NoSFX version.
+ */
+void S9xDoHBlankProcessing_SFX ()
+{
+#ifdef CPU_SHUTDOWN
+ CPU.WaitCounter++;
+#endif
+ switch (CPU.WhichEvent)
+ {
+ case HBLANK_START_EVENT:
+#ifdef ACCUMULATE_JOYPAD
+/*
+ * This call allows NDSSFC to synchronise the DS controller more often.
+ * If porting a later version of Snes9x into NDSSFC, it is essential to
+ * preserve it.
+ */
+ if ((CPU.V_Counter & 0xF) == 0)
+ NDSSFCAccumulateJoypad ();
+#endif
+ if (IPPU.HDMA && CPU.V_Counter <= PPU.ScreenHeight)
+ IPPU.HDMA = S9xDoHDMA (IPPU.HDMA);
+
+ break;
+
+ case HBLANK_END_EVENT:
+ S9xSuperFXExec ();
+
+#ifndef STORM
+ if (Settings.SoundSync)
+ S9xGenerateSound ();
+#endif
+
+ CPU.Cycles -= Settings.H_Max;
+ if (IAPU.APUExecuting)
+ {
+ APU.Cycles -= Settings.H_Max;
+#ifdef MK_APU
+ S9xCatchupCount();
+#endif
+ }
+ else
+ APU.Cycles = 0;
+
+ CPU.NextEvent = -1;
+ ICPU.Scanline++;
+
+ if (++CPU.V_Counter >= (Settings.PAL ? SNES_MAX_PAL_VCOUNTER : SNES_MAX_NTSC_VCOUNTER))
+ {
+ CPU.V_Counter = 0;
+ Memory.FillRAM[0x213F]^=0x80;
+ PPU.RangeTimeOver = 0;
+ CPU.NMIActive = FALSE;
+ ICPU.Frame++;
+ PPU.HVBeamCounterLatched = 0;
+ CPU.Flags |= SCAN_KEYS_FLAG;
+ S9xStartHDMA ();
+ }
+
+ S9xProcessSound (0);
+
+ if (PPU.VTimerEnabled && !PPU.HTimerEnabled && CPU.V_Counter == PPU.IRQVBeamPos)
+ {
+ S9xSetIRQ (PPU_V_BEAM_IRQ_SOURCE);
+ }
+
+ if (CPU.V_Counter == PPU.ScreenHeight + FIRST_VISIBLE_LINE)
+ {
+ // Start of V-blank
+ S9xEndScreenRefresh ();
+ IPPU.HDMA = 0;
+ // Bits 7 and 6 of $4212 are computed when read in S9xGetPPU.
+ missing.dma_this_frame = 0;
+ 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;
+ }
+
+ Memory.FillRAM[0x4210] = 0x80 |Model->_5A22;
+ if (Memory.FillRAM[0x4200] & 0x80)
+ {
+ CPU.NMIActive = TRUE;
+ CPU.Flags |= NMI_FLAG;
+ CPU.NMICycleCount = CPU.NMITriggerPoint;
+ }
+
+#ifdef OLD_SNAPSHOT_CODE
+ if (CPU.Flags & SAVE_SNAPSHOT_FLAG)
+ {
+ CPU.Flags &= ~SAVE_SNAPSHOT_FLAG;
+ Registers.PC = CPU.PC - CPU.PCBase;
+ S9xPackStatus ();
+ S9xAPUPackStatus ();
+ Snapshot (NULL);
+ }
+#endif
+ }
+
+ if (CPU.V_Counter == PPU.ScreenHeight + 3)
+ S9xUpdateJoypads ();
+
+ if (CPU.V_Counter == FIRST_VISIBLE_LINE)
+ {
+ Memory.FillRAM[0x4210] = Model->_5A22;
+ CPU.Flags &= ~NMI_FLAG;
+ S9xStartScreenRefresh ();
+ }
+ if (CPU.V_Counter >= FIRST_VISIBLE_LINE &&
+ CPU.V_Counter < PPU.ScreenHeight + FIRST_VISIBLE_LINE)
+ {
+ RenderLine (CPU.V_Counter - FIRST_VISIBLE_LINE);
+ }
+ // Use TimerErrorCounter to skip update of SPC700 timers once
+ // every 128 updates. Needed because this section of code is called
+ // once every emulated 63.5 microseconds, which coresponds to
+ // 15.750KHz, but the SPC700 timers need to be updated at multiples
+ // of 8KHz, hence the error correction.
+// IAPU.TimerErrorCounter++;
+// if (IAPU.TimerErrorCounter >= )
+// IAPU.TimerErrorCounter = 0;
+// else
+ {
+ if (APU.TimerEnabled [2])
+ {
+ APU.Timer [2] += 4;
+ while (APU.Timer [2] >= APU.TimerTarget [2])
+ {
+ IAPU.RAM [0xff] = (IAPU.RAM [0xff] + 1) & 0xf;
+ APU.Timer [2] -= APU.TimerTarget [2];
+#ifdef SPC700_SHUTDOWN
+ IAPU.WaitCounter++;
+ IAPU.APUExecuting = TRUE;
+#endif
+ }
+ }
+ if (CPU.V_Counter & 1)
+ {
+ if (APU.TimerEnabled [0])
+ {
+ APU.Timer [0]++;
+ if (APU.Timer [0] >= APU.TimerTarget [0])
+ {
+ IAPU.RAM [0xfd] = (IAPU.RAM [0xfd] + 1) & 0xf;
+ APU.Timer [0] = 0;
+#ifdef SPC700_SHUTDOWN
+ IAPU.WaitCounter++;
+ IAPU.APUExecuting = TRUE;
+#endif
+ }
+ }
+ if (APU.TimerEnabled [1])
+ {
+ APU.Timer [1]++;
+ if (APU.Timer [1] >= APU.TimerTarget [1])
+ {
+ IAPU.RAM [0xfe] = (IAPU.RAM [0xfe] + 1) & 0xf;
+ APU.Timer [1] = 0;
+#ifdef SPC700_SHUTDOWN
+ IAPU.WaitCounter++;
+ IAPU.APUExecuting = TRUE;
+#endif
+ }
+ }
+ }
+ }
+ break;
+
+ case HTIMER_BEFORE_EVENT:
+ case HTIMER_AFTER_EVENT:
+ if (PPU.HTimerEnabled && (!PPU.VTimerEnabled || CPU.V_Counter == PPU.IRQVBeamPos))
+ {
+ S9xSetIRQ (PPU_H_BEAM_IRQ_SOURCE);
+ }
+ break;
+ }
+
+ S9xReschedule ();
+}
+void S9xDoHBlankProcessing_NoSFX ()
+{
+#ifdef CPU_SHUTDOWN
+ CPU.WaitCounter++;
+#endif
+ switch (CPU.WhichEvent)
+ {
+ case HBLANK_START_EVENT:
+#ifdef ACCUMULATE_JOYPAD
+/*
+ * This call allows NDSSFC to synchronise the DS controller more often.
+ * If porting a later version of Snes9x into NDSSFC, it is essential to
+ * preserve it.
+ */
+ NDSSFCAccumulateJoypad ();
+#endif
+ if (IPPU.HDMA && CPU.V_Counter <= PPU.ScreenHeight)
+ IPPU.HDMA = S9xDoHDMA (IPPU.HDMA);
+
+ break;
+
+ case HBLANK_END_EVENT:
+
+#ifndef STORM
+ if (Settings.SoundSync)
+ S9xGenerateSound ();
+#endif
+
+ CPU.Cycles -= Settings.H_Max;
+ if (IAPU.APUExecuting)
+ {
+ APU.Cycles -= Settings.H_Max;
+#ifdef MK_APU
+ S9xCatchupCount();
+#endif
+ }
+ else
+ APU.Cycles = 0;
+
+ CPU.NextEvent = -1;
+ ICPU.Scanline++;
+
+ if (++CPU.V_Counter >= (Settings.PAL ? SNES_MAX_PAL_VCOUNTER : SNES_MAX_NTSC_VCOUNTER))
+ {
+ CPU.V_Counter = 0;
+ Memory.FillRAM[0x213F]^=0x80;
+ PPU.RangeTimeOver = 0;
+ CPU.NMIActive = FALSE;
+ ICPU.Frame++;
+ PPU.HVBeamCounterLatched = 0;
+ CPU.Flags |= SCAN_KEYS_FLAG;
+ S9xStartHDMA ();
+ }
+
+ S9xProcessSound (0);
+
+ if (PPU.VTimerEnabled && !PPU.HTimerEnabled && CPU.V_Counter == PPU.IRQVBeamPos)
+ {
+ S9xSetIRQ (PPU_V_BEAM_IRQ_SOURCE);
+ }
+
+ if (CPU.V_Counter == PPU.ScreenHeight + FIRST_VISIBLE_LINE)
+ {
+ // Start of V-blank
+ S9xEndScreenRefresh ();
+ IPPU.HDMA = 0;
+ // Bits 7 and 6 of $4212 are computed when read in S9xGetPPU.
+ missing.dma_this_frame = 0;
+ 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;
+ }
+
+ Memory.FillRAM[0x4210] = 0x80 |Model->_5A22;
+ if (Memory.FillRAM[0x4200] & 0x80)
+ {
+ CPU.NMIActive = TRUE;
+ CPU.Flags |= NMI_FLAG;
+ CPU.NMICycleCount = CPU.NMITriggerPoint;
+ }
+
+#ifdef OLD_SNAPSHOT_CODE
+ if (CPU.Flags & SAVE_SNAPSHOT_FLAG)
+ {
+ CPU.Flags &= ~SAVE_SNAPSHOT_FLAG;
+ Registers.PC = CPU.PC - CPU.PCBase;
+ S9xPackStatus ();
+ S9xAPUPackStatus ();
+ Snapshot (NULL);
+ }
+#endif
+ }
+
+ if (CPU.V_Counter == PPU.ScreenHeight + 3)
+ S9xUpdateJoypads ();
+
+ if (CPU.V_Counter == FIRST_VISIBLE_LINE)
+ {
+ Memory.FillRAM[0x4210] = Model->_5A22;
+ CPU.Flags &= ~NMI_FLAG;
+ S9xStartScreenRefresh ();
+ }
+ if (CPU.V_Counter >= FIRST_VISIBLE_LINE &&
+ CPU.V_Counter < PPU.ScreenHeight + FIRST_VISIBLE_LINE)
+ {
+ RenderLine (CPU.V_Counter - FIRST_VISIBLE_LINE);
+ }
+ // Use TimerErrorCounter to skip update of SPC700 timers once
+ // every 128 updates. Needed because this section of code is called
+ // once every emulated 63.5 microseconds, which coresponds to
+ // 15.750KHz, but the SPC700 timers need to be updated at multiples
+ // of 8KHz, hence the error correction.
+// IAPU.TimerErrorCounter++;
+// if (IAPU.TimerErrorCounter >= )
+// IAPU.TimerErrorCounter = 0;
+// else
+ {
+ if (APU.TimerEnabled [2])
+ {
+ APU.Timer [2] += 4;
+ while (APU.Timer [2] >= APU.TimerTarget [2])
+ {
+ IAPU.RAM [0xff] = (IAPU.RAM [0xff] + 1) & 0xf;
+ APU.Timer [2] -= APU.TimerTarget [2];
+#ifdef SPC700_SHUTDOWN
+ IAPU.WaitCounter++;
+ IAPU.APUExecuting = TRUE;
+#endif
+ }
+ }
+ if (CPU.V_Counter & 1)
+ {
+ if (APU.TimerEnabled [0])
+ {
+ APU.Timer [0]++;
+ if (APU.Timer [0] >= APU.TimerTarget [0])
+ {
+ IAPU.RAM [0xfd] = (IAPU.RAM [0xfd] + 1) & 0xf;
+ APU.Timer [0] = 0;
+#ifdef SPC700_SHUTDOWN
+ IAPU.WaitCounter++;
+ IAPU.APUExecuting = TRUE;
+#endif
+ }
+ }
+ if (APU.TimerEnabled [1])
+ {
+ APU.Timer [1]++;
+ if (APU.Timer [1] >= APU.TimerTarget [1])
+ {
+ IAPU.RAM [0xfe] = (IAPU.RAM [0xfe] + 1) & 0xf;
+ APU.Timer [1] = 0;
+#ifdef SPC700_SHUTDOWN
+ IAPU.WaitCounter++;
+ IAPU.APUExecuting = TRUE;
+#endif
+ }
+ }
+ }
+ }
+ break;
+
+ case HTIMER_BEFORE_EVENT:
+ case HTIMER_AFTER_EVENT:
+ if (PPU.HTimerEnabled && (!PPU.VTimerEnabled || CPU.V_Counter == PPU.IRQVBeamPos))
+ {
+ S9xSetIRQ (PPU_H_BEAM_IRQ_SOURCE);
+ }
+ break;
+ }
+
+ S9xReschedule ();
+}
+