snes9x/sa1cpu.cpp

231 lines
5.8 KiB
C++

/*****************************************************************************\
Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
This file is licensed under the Snes9x License.
For further information, consult the LICENSE file in the root directory.
\*****************************************************************************/
#include "snes9x.h"
#include "memmap.h"
#define CPU SA1
#define ICPU SA1
#define Registers SA1Registers
#define OpenBus SA1OpenBus
#define S9xGetByte S9xSA1GetByte
#define S9xGetWord S9xSA1GetWord
#define S9xSetByte S9xSA1SetByte
#define S9xSetWord S9xSA1SetWord
#define S9xSetPCBase S9xSA1SetPCBase
#define S9xOpcodesM1X1 S9xSA1OpcodesM1X1
#define S9xOpcodesM1X0 S9xSA1OpcodesM1X0
#define S9xOpcodesM0X1 S9xSA1OpcodesM0X1
#define S9xOpcodesM0X0 S9xSA1OpcodesM0X0
#define S9xOpcodesE1 S9xSA1OpcodesE1
#define S9xOpcodesSlow S9xSA1OpcodesSlow
#define S9xOpcode_IRQ S9xSA1Opcode_IRQ
#define S9xOpcode_NMI S9xSA1Opcode_NMI
#define S9xUnpackStatus S9xSA1UnpackStatus
#define S9xPackStatus S9xSA1PackStatus
#define S9xFixCycles S9xSA1FixCycles
#define Immediate8 SA1Immediate8
#define Immediate16 SA1Immediate16
#define Relative SA1Relative
#define RelativeLong SA1RelativeLong
#define Absolute SA1Absolute
#define AbsoluteLong SA1AbsoluteLong
#define AbsoluteIndirect SA1AbsoluteIndirect
#define AbsoluteIndirectLong SA1AbsoluteIndirectLong
#define AbsoluteIndexedIndirect SA1AbsoluteIndexedIndirect
#define Direct SA1Direct
#define DirectIndirectIndexed SA1DirectIndirectIndexed
#define DirectIndirectIndexedLong SA1DirectIndirectIndexedLong
#define DirectIndexedIndirect SA1DirectIndexedIndirect
#define DirectIndexedX SA1DirectIndexedX
#define DirectIndexedY SA1DirectIndexedY
#define AbsoluteIndexedX SA1AbsoluteIndexedX
#define AbsoluteIndexedY SA1AbsoluteIndexedY
#define AbsoluteLongIndexedX SA1AbsoluteLongIndexedX
#define DirectIndirect SA1DirectIndirect
#define DirectIndirectLong SA1DirectIndirectLong
#define StackRelative SA1StackRelative
#define StackRelativeIndirectIndexed SA1StackRelativeIndirectIndexed
#define SA1_OPCODES
#include "cpuops.cpp"
static void S9xSA1UpdateTimer (void);
void S9xSA1MainLoop (void)
{
if (Memory.FillRAM[0x2200] & 0x60)
{
SA1.Cycles += 6; // FIXME
S9xSA1UpdateTimer();
return;
}
// SA-1 NMI
if ((Memory.FillRAM[0x2200] & 0x10) && !(Memory.FillRAM[0x220b] & 0x10))
{
Memory.FillRAM[0x2301] |= 0x10;
Memory.FillRAM[0x220b] |= 0x10;
if (SA1.WaitingForInterrupt)
{
SA1.WaitingForInterrupt = FALSE;
SA1Registers.PCw++;
}
S9xSA1Opcode_NMI();
}
else
if (!SA1CheckFlag(IRQ))
{
// SA-1 Timer IRQ
if ((Memory.FillRAM[0x220a] & 0x40) && !(Memory.FillRAM[0x220b] & 0x40))
{
Memory.FillRAM[0x2301] |= 0x40;
if (SA1.WaitingForInterrupt)
{
SA1.WaitingForInterrupt = FALSE;
SA1Registers.PCw++;
}
S9xSA1Opcode_IRQ();
}
else
// SA-1 DMA IRQ
if ((Memory.FillRAM[0x220a] & 0x20) && !(Memory.FillRAM[0x220b] & 0x20))
{
Memory.FillRAM[0x2301] |= 0x20;
if (SA1.WaitingForInterrupt)
{
SA1.WaitingForInterrupt = FALSE;
SA1Registers.PCw++;
}
S9xSA1Opcode_IRQ();
}
else
// SA-1 IRQ
if ((Memory.FillRAM[0x2200] & 0x80) && !(Memory.FillRAM[0x220b] & 0x80))
{
Memory.FillRAM[0x2301] |= 0x80;
if (SA1.WaitingForInterrupt)
{
SA1.WaitingForInterrupt = FALSE;
SA1Registers.PCw++;
}
S9xSA1Opcode_IRQ();
}
}
#undef CPU
int cycles = CPU.Cycles * 3;
#define CPU SA1
for (; SA1.Cycles < cycles && !(Memory.FillRAM[0x2200] & 0x60);)
{
#ifdef DEBUGGER
if (SA1.Flags & TRACE_FLAG)
S9xSA1Trace();
#endif
uint8 Op;
struct SOpcodes *Opcodes;
if (SA1.PCBase)
{
SA1OpenBus = Op = SA1.PCBase[Registers.PCw];
Opcodes = SA1.S9xOpcodes;
SA1.Cycles += SA1.MemSpeed;
}
else
{
Op = S9xSA1GetByte(Registers.PBPC);
Opcodes = S9xOpcodesSlow;
}
if ((SA1Registers.PCw & MEMMAP_MASK) + SA1.S9xOpLengths[Op] >= MEMMAP_BLOCK_SIZE)
{
uint32 oldPC = SA1Registers.PBPC;
S9xSA1SetPCBase(SA1Registers.PBPC);
SA1Registers.PBPC = oldPC;
Opcodes = S9xSA1OpcodesSlow;
}
Registers.PCw++;
(*Opcodes[Op].S9xOpcode)();
}
S9xSA1UpdateTimer();
}
static void S9xSA1UpdateTimer (void) // FIXME
{
SA1.PrevHCounter = SA1.HCounter;
if (Memory.FillRAM[0x2210] & 0x80)
{
SA1.HCounter += (SA1.Cycles - SA1.PrevCycles);
if (SA1.HCounter >= 0x800)
{
SA1.HCounter -= 0x800;
SA1.PrevHCounter -= 0x800;
if (++SA1.VCounter >= 0x200)
SA1.VCounter = 0;
}
}
else
{
SA1.HCounter += (SA1.Cycles - SA1.PrevCycles);
if (SA1.HCounter >= Timings.H_Max_Master)
{
SA1.HCounter -= Timings.H_Max_Master;
SA1.PrevHCounter -= Timings.H_Max_Master;
if (++SA1.VCounter >= Timings.V_Max_Master)
SA1.VCounter = 0;
}
}
SA1.PrevCycles = SA1.Cycles;
bool8 thisIRQ = Memory.FillRAM[0x2210] & 0x03;
if (Memory.FillRAM[0x2210] & 0x01)
{
if (SA1.PrevHCounter >= SA1.HTimerIRQPos * ONE_DOT_CYCLE || SA1.HCounter < SA1.HTimerIRQPos * ONE_DOT_CYCLE)
thisIRQ = FALSE;
}
if (Memory.FillRAM[0x2210] & 0x02)
{
if (SA1.VCounter != SA1.VTimerIRQPos * ONE_DOT_CYCLE)
thisIRQ = FALSE;
}
// SA-1 Timer IRQ control
if (!SA1.TimerIRQLastState && thisIRQ)
{
Memory.FillRAM[0x2301] |= 0x40;
if (Memory.FillRAM[0x220a] & 0x40)
{
Memory.FillRAM[0x220b] &= ~0x40;
#ifdef DEBUGGER
S9xTraceFormattedMessage("--- SA-1 Timer IRQ triggered prev HC:%04d curr HC:%04d HTimer:%d Pos:%04d VTimer:%d Pos:%03d",
SA1.PrevHCounter, SA1.HCounter,
(Memory.FillRAM[0x2210] & 0x01) ? 1 : 0, SA1.HTimerIRQPos * ONE_DOT_CYCLE,
(Memory.FillRAM[0x2210] & 0x02) ? 1 : 0, SA1.VTimerIRQPos);
#endif
}
}
SA1.TimerIRQLastState = thisIRQ;
}