nestopia/source/core/board/NstBoardMmc3.cpp
2012-09-02 13:13:55 -04:00

320 lines
7.2 KiB
C++

////////////////////////////////////////////////////////////////////////////////////////
//
// Nestopia - NES/Famicom emulator written in C++
//
// Copyright (C) 2003-2008 Martin Freij
//
// This file is part of Nestopia.
//
// Nestopia is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// Nestopia is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Nestopia; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
////////////////////////////////////////////////////////////////////////////////////////
#include "../NstLog.hpp"
#include "NstBoard.hpp"
#include "NstBoardMmc3.hpp"
namespace Nes
{
namespace Core
{
namespace Boards
{
#ifdef NST_MSVC_OPTIMIZE
#pragma optimize("s", on)
#endif
Mmc3::Mmc3(const Context& c,Revision revision)
:
Board (c),
irq (*c.cpu,*c.ppu,revision != REV_A)
{
switch (revision)
{
case Mmc3::REV_A: Log::Flush( "Board: MMC rev. A" NST_LINEBREAK ); break;
case Mmc3::REV_B: Log::Flush( "Board: MMC rev. B" NST_LINEBREAK ); break;
case Mmc3::REV_C: Log::Flush( "Board: MMC rev. C" NST_LINEBREAK ); break;
}
}
void Mmc3::BaseIrq::Reset(const bool hard)
{
if (hard)
{
count = 0;
latch = 0;
reload = false;
enabled = false;
}
}
void Mmc3::SubReset(const bool hard)
{
if (hard)
{
regs.ctrl0 = 0;
regs.ctrl1 = 0;
banks.prg[0] = 0x00;
banks.prg[1] = 0x01;
banks.prg[2] = 0x3E;
banks.prg[3] = 0x3F;
for (uint i=0; i < 8; ++i)
banks.chr[i] = i;
wrk.Source().SetSecurity( false, false );
}
irq.Reset( hard );
for (uint i=0x0000; i < 0x2000; i += 0x2)
{
Map( 0x8000 + i, &Mmc3::Poke_8000 );
Map( 0x8001 + i, &Mmc3::Poke_8001 );
Map( 0xA001 + i, &Mmc3::Poke_A001 );
Map( 0xC000 + i, &Mmc3::Poke_C000 );
Map( 0xC001 + i, &Mmc3::Poke_C001 );
Map( 0xE000 + i, &Mmc3::Poke_E000 );
Map( 0xE001 + i, &Mmc3::Poke_E001 );
}
if (board.GetNmt() != Type::NMT_FOURSCREEN)
{
for (uint i=0x0000; i < 0x2000; i += 0x2)
Map( 0xA000 + i, NMT_SWAP_HV );
}
UpdatePrg();
UpdateChr();
}
void Mmc3::BaseIrq::LoadState(State::Loader& state)
{
State::Loader::Data<3> data( state );
enabled = data[0] & 0x1;
reload = data[0] & 0x2;
count = data[1];
latch = data[2];
}
void Mmc3::BaseIrq::SaveState(State::Saver& state,const dword chunk) const
{
const byte data[3] =
{
(enabled ? 0x1U : 0x0U) | (reload ? 0x2U : 0x0U),
count,
latch
};
state.Begin( chunk ).Write( data ).End();
}
void Mmc3::SubLoad(State::Loader& state,const dword baseChunk)
{
NST_VERIFY( baseChunk == (AsciiId<'M','M','3'>::V) );
if (baseChunk == AsciiId<'M','M','3'>::V)
{
while (const dword chunk = state.Begin())
{
switch (chunk)
{
case AsciiId<'R','E','G'>::V:
{
State::Loader::Data<12> data( state );
regs.ctrl0 = data[0];
regs.ctrl1 = data[1];
banks.prg[0] = data[2] & 0x3FU;
banks.prg[1] = data[3] & 0x3FU;
banks.chr[0] = (data[6] & 0x7FU) << 1;
banks.chr[1] = banks.chr[0] | 0x01U;
banks.chr[2] = (data[7] & 0x7FU) << 1;
banks.chr[3] = banks.chr[2] | 0x01U;
banks.chr[4] = data[8];
banks.chr[5] = data[9];
banks.chr[6] = data[10];
banks.chr[7] = data[11];
break;
}
case AsciiId<'I','R','Q'>::V:
irq.unit.LoadState( state );
break;
}
state.End();
}
}
}
void Mmc3::SubSave(State::Saver& state) const
{
state.Begin( AsciiId<'M','M','3'>::V );
const byte data[12] =
{
regs.ctrl0,
regs.ctrl1,
banks.prg[0],
banks.prg[1],
0x3E,
0x3F,
banks.chr[0] >> 1,
banks.chr[2] >> 1,
banks.chr[4],
banks.chr[5],
banks.chr[6],
banks.chr[7]
};
state.Begin( AsciiId<'R','E','G'>::V ).Write( data ).End();
irq.unit.SaveState( state, AsciiId<'I','R','Q'>::V );
state.End();
}
#ifdef NST_MSVC_OPTIMIZE
#pragma optimize("", on)
#endif
NES_POKE_D(Mmc3,8000)
{
const uint diff = regs.ctrl0 ^ data;
regs.ctrl0 = data;
if (diff & 0x40)
{
const uint v[2] =
{
banks.prg[(data >> 5 & 0x2) ^ 0],
banks.prg[(data >> 5 & 0x2) ^ 2]
};
UpdatePrg( 0x0000, v[0] );
UpdatePrg( 0x4000, v[1] );
}
if (diff & 0x80)
UpdateChr();
}
NES_POKE_D(Mmc3,8001)
{
uint address = regs.ctrl0 & 0x7;
if (address < 6)
{
ppu.Update();
uint base = regs.ctrl0 << 5 & 0x1000;
if (address < 2)
{
address <<= 1;
base |= address << 10;
UpdateChr( base | 0x0000, (banks.chr[address+0] = data & 0xFE) );
UpdateChr( base | 0x0400, (banks.chr[address+1] = data | 0x01) );
}
else
{
UpdateChr( (base ^ 0x1000) | (address-2) << 10, (banks.chr[address+2] = data) );
}
}
else
{
UpdatePrg( (address == 6) ? (regs.ctrl0 << 8 & 0x4000) : 0x2000, (banks.prg[address-6] = data & 0x3F) );
}
}
NES_POKE_D(Mmc3,A001)
{
regs.ctrl1 = data;
wrk.Source().SetSecurity
(
(data & CTRL1_WRAM_ENABLED),
(data & CTRL1_WRAM) == CTRL1_WRAM_ENABLED && board.GetWram()
);
}
NES_POKE_D(Mmc3,C000)
{
irq.Update();
irq.unit.SetLatch( data );
}
NES_POKE(Mmc3,C001)
{
irq.Update();
irq.unit.Reload();
}
NES_POKE(Mmc3,E000)
{
irq.Update();
irq.unit.Disable( cpu );
}
NES_POKE(Mmc3,E001)
{
irq.Update();
irq.unit.Enable();
}
void NST_FASTCALL Mmc3::UpdatePrg(uint address,uint bank)
{
prg.SwapBank<SIZE_8K>( address, bank );
}
void NST_FASTCALL Mmc3::UpdateChr(uint address,uint bank) const
{
chr.SwapBank<SIZE_1K>( address, bank );
}
void Mmc3::UpdatePrg()
{
const uint x = regs.ctrl0 >> 5 & 0x2;
UpdatePrg( 0x0000, banks.prg[0^x] );
UpdatePrg( 0x2000, banks.prg[1^0] );
UpdatePrg( 0x4000, banks.prg[2^x] );
UpdatePrg( 0x6000, banks.prg[3^0] );
}
void Mmc3::UpdateChr() const
{
ppu.Update();
const uint x = regs.ctrl0 >> 5 & 0x4;
for (uint i=0; i < 8; ++i)
UpdateChr( i * SIZE_1K, banks.chr[i^x] );
}
void Mmc3::Sync(Event event,Input::Controllers* controllers)
{
if (event == EVENT_END_FRAME)
irq.VSync();
Board::Sync( event, controllers );
}
}
}
}