infones_mapper.cpp

游戏模拟器InfoNes的原代码。有兴趣的可以将它移植到linux下

void Map5_Sram( WORD wAddr, BYTE byData )
{
  if ( Map5_Wram_Protect0 == 0x02 && Map5_Wram_Protect1 == 0x01 )
  {
    if ( Map5_Wram_Reg[ 3 ] != 0xff )
    {
      Map5_Wram[ 0x2000 * Map5_Wram_Reg[ 3 ] + ( wAddr - 0x6000) ] = byData;
    }
  }
}

/*-------------------------------------------------------------------*/
/*  Mapper 5 Write Function                                          */
/*-------------------------------------------------------------------*/
void Map5_Write( WORD wAddr, BYTE byData )
{
  if ( Map5_Wram_Protect0 == 0x02 && Map5_Wram_Protect1 == 0x01 )
  {
    switch ( wAddr & 0xe000 )
    {
      case 0x8000:      /* $8000-$9fff */
        if ( Map5_Wram_Reg[ 4 ] != 0xff )
        {
          Map5_Wram[ 0x2000 * Map5_Wram_Reg[ 4 ] + ( wAddr - 0x8000) ] = byData;
        }
        break;

      case 0xa000:      /* $a000-$bfff */
        if ( Map5_Wram_Reg[ 5 ] != 0xff )
        {
          Map5_Wram[ 0x2000 * Map5_Wram_Reg[ 5 ] + ( wAddr - 0xa000) ] = byData;
        }
        break;

      case 0xc000:      /* $c000-$dfff */
        if ( Map5_Wram_Reg[ 6 ] != 0xff )
        {
          Map5_Wram[ 0x2000 * Map5_Wram_Reg[ 6 ] + ( wAddr - 0xc000) ] = byData;
        }
        break;
    }
  }
}

/*-------------------------------------------------------------------*/
/*  Mapper 5 H-Sync Function                                         */
/*-------------------------------------------------------------------*/
void Map5_HSync()
{
  if ( PPU_Scanline <= 240 )
  {
    if ( PPU_Scanline == Map5_IRQ_Line )
    {
      Map5_IRQ_Status |= 0x80;

      if ( Map5_IRQ_Enable && Map5_IRQ_Line < 0xf0 )
      {
        IRQ_REQ;
      }
      if ( Map5_IRQ_Line >= 0x40 )
      {
        Map5_IRQ_Enable = 0;
      }
    }
  } else {
    Map5_IRQ_Status |= 0x40;
  }
}

/*-------------------------------------------------------------------*/
/*  Mapper 5 Rendering Screen Function                               */
/*-------------------------------------------------------------------*/
void Map5_RenderScreen( BYTE byMode )
{
  DWORD dwPage[ 8 ];

  switch ( Map5_Chr_Size )
  {
    case 0:
      dwPage[ 7 ] = ( (DWORD)Map5_Chr_Reg[7][byMode] << 3 ) % ( NesHeader.byVRomSize << 3 );

      PPUBANK[ 0 ] = VROMPAGE( dwPage[ 7 ] + 0 );
      PPUBANK[ 1 ] = VROMPAGE( dwPage[ 7 ] + 1 );
      PPUBANK[ 2 ] = VROMPAGE( dwPage[ 7 ] + 2 );
      PPUBANK[ 3 ] = VROMPAGE( dwPage[ 7 ] + 3 );
      PPUBANK[ 4 ] = VROMPAGE( dwPage[ 7 ] + 4 );
      PPUBANK[ 5 ] = VROMPAGE( dwPage[ 7 ] + 5 );
      PPUBANK[ 6 ] = VROMPAGE( dwPage[ 7 ] + 6 );
      PPUBANK[ 7 ] = VROMPAGE( dwPage[ 7 ] + 7 );
      InfoNES_SetupChr();
      break;

    case 1:
      dwPage[ 3 ] = ( (DWORD)Map5_Chr_Reg[3][byMode] << 2 ) % ( NesHeader.byVRomSize << 3 );
      dwPage[ 7 ] = ( (DWORD)Map5_Chr_Reg[7][byMode] << 2 ) % ( NesHeader.byVRomSize << 3 );

      PPUBANK[ 0 ] = VROMPAGE( dwPage[ 3 ] + 0 );
      PPUBANK[ 1 ] = VROMPAGE( dwPage[ 3 ] + 1 );
      PPUBANK[ 2 ] = VROMPAGE( dwPage[ 3 ] + 2 );
      PPUBANK[ 3 ] = VROMPAGE( dwPage[ 3 ] + 3 );
      PPUBANK[ 4 ] = VROMPAGE( dwPage[ 7 ] + 0 );
      PPUBANK[ 5 ] = VROMPAGE( dwPage[ 7 ] + 1 );
      PPUBANK[ 6 ] = VROMPAGE( dwPage[ 7 ] + 2 );
      PPUBANK[ 7 ] = VROMPAGE( dwPage[ 7 ] + 3 );
     InfoNES_SetupChr();
      break;

    case 2:
      dwPage[ 1 ] = ( (DWORD)Map5_Chr_Reg[1][byMode] << 1 ) % ( NesHeader.byVRomSize << 3 );
      dwPage[ 3 ] = ( (DWORD)Map5_Chr_Reg[3][byMode] << 1 ) % ( NesHeader.byVRomSize << 3 );
      dwPage[ 5 ] = ( (DWORD)Map5_Chr_Reg[5][byMode] << 1 ) % ( NesHeader.byVRomSize << 3 );
      dwPage[ 7 ] = ( (DWORD)Map5_Chr_Reg[7][byMode] << 1 ) % ( NesHeader.byVRomSize << 3 );

      PPUBANK[ 0 ] = VROMPAGE( dwPage[ 1 ] + 0 );
      PPUBANK[ 1 ] = VROMPAGE( dwPage[ 1 ] + 1 );
      PPUBANK[ 2 ] = VROMPAGE( dwPage[ 3 ] + 0 );
      PPUBANK[ 3 ] = VROMPAGE( dwPage[ 3 ] + 1 );
      PPUBANK[ 4 ] = VROMPAGE( dwPage[ 5 ] + 0 );
      PPUBANK[ 5 ] = VROMPAGE( dwPage[ 5 ] + 1 );
      PPUBANK[ 6 ] = VROMPAGE( dwPage[ 7 ] + 0 );
      PPUBANK[ 7 ] = VROMPAGE( dwPage[ 7 ] + 1 );
      InfoNES_SetupChr();
      break;

    default:
      dwPage[ 0 ] = (DWORD)Map5_Chr_Reg[0][byMode] % ( NesHeader.byVRomSize << 3 );
      dwPage[ 1 ] = (DWORD)Map5_Chr_Reg[1][byMode] % ( NesHeader.byVRomSize << 3 );
      dwPage[ 2 ] = (DWORD)Map5_Chr_Reg[2][byMode] % ( NesHeader.byVRomSize << 3 );
      dwPage[ 3 ] = (DWORD)Map5_Chr_Reg[3][byMode] % ( NesHeader.byVRomSize << 3 );
      dwPage[ 4 ] = (DWORD)Map5_Chr_Reg[4][byMode] % ( NesHeader.byVRomSize << 3 );
      dwPage[ 5 ] = (DWORD)Map5_Chr_Reg[5][byMode] % ( NesHeader.byVRomSize << 3 );
      dwPage[ 6 ] = (DWORD)Map5_Chr_Reg[6][byMode] % ( NesHeader.byVRomSize << 3 );
      dwPage[ 7 ] = (DWORD)Map5_Chr_Reg[7][byMode] % ( NesHeader.byVRomSize << 3 );

      PPUBANK[ 0 ] = VROMPAGE( dwPage[ 0 ] );
      PPUBANK[ 1 ] = VROMPAGE( dwPage[ 1 ] );
      PPUBANK[ 2 ] = VROMPAGE( dwPage[ 2 ] );
      PPUBANK[ 3 ] = VROMPAGE( dwPage[ 3 ] );
      PPUBANK[ 4 ] = VROMPAGE( dwPage[ 4 ] );
      PPUBANK[ 5 ] = VROMPAGE( dwPage[ 5 ] );
      PPUBANK[ 6 ] = VROMPAGE( dwPage[ 6 ] );
      PPUBANK[ 7 ] = VROMPAGE( dwPage[ 7 ] );
      InfoNES_SetupChr();
      break;
  }
}

/*-------------------------------------------------------------------*/
/*  Mapper 5 Sync Program Banks Function                             */
/*-------------------------------------------------------------------*/
void Map5_Sync_Prg_Banks( void )
{
  switch( Map5_Prg_Size )
  {
    case 0:
      Map5_Wram_Reg[ 4 ] = 0xff;
      Map5_Wram_Reg[ 5 ] = 0xff;
      Map5_Wram_Reg[ 6 ] = 0xff;

      ROMBANK0 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7c) + 0 ) % ( NesHeader.byRomSize << 1 ) );
      ROMBANK1 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7c) + 1 ) % ( NesHeader.byRomSize << 1 ) );
      ROMBANK2 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7c) + 2 ) % ( NesHeader.byRomSize << 1 ) );
      ROMBANK3 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7c) + 3 ) % ( NesHeader.byRomSize << 1 ) );
      break;

    case 1:
      if ( Map5_Prg_Reg[ 5 ] & 0x80 )
      {
        Map5_Wram_Reg[ 4 ] = 0xff;
        Map5_Wram_Reg[ 5 ] = 0xff;
        ROMBANK0 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7e) + 0 ) % ( NesHeader.byRomSize << 1 ) );
        ROMBANK1 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7e) + 1 ) % ( NesHeader.byRomSize << 1 ) );
      } else {
        Map5_Wram_Reg[ 4 ] = ( Map5_Prg_Reg[ 5 ] & 0x06 ) + 0;
        Map5_Wram_Reg[ 5 ] = ( Map5_Prg_Reg[ 5 ] & 0x06 ) + 1;
        ROMBANK0 = Map5_ROMPAGE( Map5_Wram_Reg[ 4 ] );
        ROMBANK1 = Map5_ROMPAGE( Map5_Wram_Reg[ 5 ] );
      }

      Map5_Wram_Reg[ 6 ] = 0xff;
      ROMBANK2 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7e) + 0 ) % ( NesHeader.byRomSize << 1 ) );
      ROMBANK3 = ROMPAGE( ( (Map5_Prg_Reg[7] & 0x7e) + 1 ) % ( NesHeader.byRomSize << 1 ) );
      break;

    case 2:
      if ( Map5_Prg_Reg[ 5 ] & 0x80 )
      {
        Map5_Wram_Reg[ 4 ] = 0xff;
        Map5_Wram_Reg[ 5 ] = 0xff;
        ROMBANK0 = ROMPAGE( ( (Map5_Prg_Reg[5] & 0x7e) + 0 ) % ( NesHeader.byRomSize << 1 ) );
        ROMBANK1 = ROMPAGE( ( (Map5_Prg_Reg[5] & 0x7e) + 1 ) % ( NesHeader.byRomSize << 1 ) );
      } else {
        Map5_Wram_Reg[ 4 ] = ( Map5_Prg_Reg[ 5 ] & 0x06 ) + 0;
        Map5_Wram_Reg[ 5 ] = ( Map5_Prg_Reg[ 5 ] & 0x06 ) + 1;
        ROMBANK0 = Map5_ROMPAGE( Map5_Wram_Reg[ 4 ] );
        ROMBANK1 = Map5_ROMPAGE( Map5_Wram_Reg[ 5 ] );
      }

      if ( Map5_Prg_Reg[ 6 ] & 0x80 )
      {
        Map5_Wram_Reg[ 6 ] = 0xff;
        ROMBANK2 = ROMPAGE( (Map5_Prg_Reg[6] & 0x7f) % ( NesHeader.byRomSize << 1 ) );
      } else {
        Map5_Wram_Reg[ 6 ] = Map5_Prg_Reg[ 6 ] & 0x07;
        ROMBANK2 = Map5_ROMPAGE( Map5_Wram_Reg[ 6 ] );
      }

      ROMBANK3 = ROMPAGE( (Map5_Prg_Reg[7] & 0x7f) % ( NesHeader.byRomSize << 1 ) );
      break;

    default:
      if ( Map5_Prg_Reg[ 4 ] & 0x80 )
      {
        Map5_Wram_Reg[ 4 ] = 0xff;
        ROMBANK0 = ROMPAGE( (Map5_Prg_Reg[4] & 0x7f) % ( NesHeader.byRomSize << 1 ) );
      } else {
        Map5_Wram_Reg[ 4 ] = Map5_Prg_Reg[ 4 ] & 0x07;
        ROMBANK0 = Map5_ROMPAGE( Map5_Wram_Reg[ 4 ] );
      }

      if ( Map5_Prg_Reg[ 5 ] & 0x80 )
      {
        Map5_Wram_Reg[ 5 ] = 0xff;
        ROMBANK1 = ROMPAGE( (Map5_Prg_Reg[5] & 0x7f) % ( NesHeader.byRomSize << 1 ) );
      } else {
        Map5_Wram_Reg[ 5 ] = Map5_Prg_Reg[ 5 ] & 0x07;
        ROMBANK1 = Map5_ROMPAGE( Map5_Wram_Reg[ 5 ] );
      }

      if ( Map5_Prg_Reg[ 6 ] & 0x80 )
      {
        Map5_Wram_Reg[ 6 ] = 0xff;
        ROMBANK2 = ROMPAGE( (Map5_Prg_Reg[6] & 0x7f) % ( NesHeader.byRomSize << 1 ) );
      } else {
        Map5_Wram_Reg[ 6 ] = Map5_Prg_Reg[ 6 ] & 0x07;
        ROMBANK2 = Map5_ROMPAGE( Map5_Wram_Reg[ 6 ] );
      }

      ROMBANK3 = ROMPAGE( (Map5_Prg_Reg[7] & 0x7f) % ( NesHeader.byRomSize << 1 ) );
      break;
  }
}

/*===================================================================*/
/*                                                                   */
/*                       Mapper 6 (FFE)                              */
/*                                                                   */
/*===================================================================*/

BYTE Map6_IRQ_Enable;
DWORD Map6_IRQ_Cnt;
BYTE Map6_Chr_Ram[ 0x2000 * 4 ];

/*-------------------------------------------------------------------*/
/*  Initialize Mapper 6                                              */
/*-------------------------------------------------------------------*/
void Map6_Init()
{
  int nPage;

  /* Initialize Mapper */
  MapperInit = Map6_Init;

  /* Write to Mapper */
  MapperWrite = Map6_Write;

  /* Write to SRAM */
  MapperSram = Map0_Sram;

  /* Write to APU */
  MapperApu = Map6_Apu;

  /* Read from APU */
  MapperReadApu = Map0_ReadApu;

  /* Callback at VSync */
  MapperVSync = Map0_VSync;

  /* Callback at HSync */
  MapperHSync = Map6_HSync;

  /* Callback at PPU */
  MapperPPU = Map0_PPU;

  /* Callback at Rendering Screen ( 1:BG, 0:Sprite ) */
  MapperRenderScreen = Map0_RenderScreen;

  /* Set ROM Banks */
  ROMBANK0 = ROMPAGE( 0 );
  ROMBANK1 = ROMPAGE( 1 );
  ROMBANK2 = ROMPAGE( 14 );
  ROMBANK3 = ROMPAGE( 15 );

  /* Set PPU Banks */
  if ( NesHeader.byVRomSize > 0 )
  {
    for ( nPage = 0; nPage < 8; ++nPage )
    {
      PPUBANK[ nPage ] = VROMPAGE( nPage );
    }
    InfoNES_SetupChr();
  }
  else
  {
    for ( nPage = 0; nPage < 8; ++nPage )
    {
      PPUBANK[ nPage ] = Map6_VROMPAGE( nPage );
    }
    InfoNES_SetupChr();
  }

  /* Set up wiring of the interrupt pin */
  K6502_Set_Int_Wiring( 1, 1 ); 
}

/*-------------------------------------------------------------------*/
/*  Mapper 6 Write to APU Function                                   */
/*-------------------------------------------------------------------*/
void Map6_Apu( WORD wAddr, BYTE byData )
{
  switch ( wAddr )
  {
    /* Name Table Mirroring */
    case 0x42fe:
      if ( byData & 0x10 )
      {
        InfoNES_Mirroring( 2 );
      } else {
        InfoNES_Mirroring( 3 );
      }
      break;

    case 0x42ff:
      if ( byData & 0x10 )
      {
        InfoNES_Mirroring( 0 );
      } else {
        InfoNES_Mirroring( 1 );
      }
      break;

    case 0x4501:
      Map6_IRQ_Enable = 0;
      break;

    case 0x4502:
      Map6_IRQ_Cnt = ( Map6_IRQ_Cnt & 0xff00 ) | (DWORD)byData;
      break;

    case 0x4503:
      Map6_IRQ_Cnt = ( Map6_IRQ_Cnt & 0x00ff ) | ( (DWORD)byData << 8 );
      Map6_IRQ_Enable = 1;
      break;
  }
}

/*-------------------------------------------------------------------*/
/*  Mapper 6 Write Function                                          */
/*-------------------------------------------------------------------*/
void Map6_Write( WORD wAddr, BYTE byData )
{
  BYTE byPrgBank = ( byData & 0x3c ) >> 2;
  BYTE byChrBank = byData & 0x03;

  /* Set ROM Banks */
  byPrgBank <<= 1;
  byPrgBank %= ( NesHeader.byRomSize << 1 );

  ROMBANK0 = ROMPAGE( byPrgBank );
  ROMBANK1 = ROMPAGE( byPrgBank + 1 );

  /* Set PPU Banks */
  PPUBANK[ 0 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 0 * 0x400 ];
  PPUBANK[ 1 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 1 * 0x400 ];
  PPUBANK[ 2 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 2 * 0x400 ];
  PPUBANK[ 3 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 3 * 0x400 ];
  PPUBANK[ 4 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 4 * 0x400 ];
  PPUBANK[ 5 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 5 * 0x400 ];
  PPUBANK[ 6 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 6 * 0x400 ];
  PPUBANK[ 7 ] = &Map6_Chr_Ram[ byChrBank * 0x2000 + 7 * 0x400 ];
  InfoNES_SetupChr();
}

/*-------------------------------------------------------------------*/
/*  Mapper 6 H-Sync Function                                         */
/*-------------------------------------------------------------------*/
void Map6_HSync()
{
  if ( Map6_IRQ_Enable )
  {
    Map6_IRQ_Cnt += 133;
    if ( Map6_IRQ_Cnt >= 0xffff )
    {
      IRQ_REQ;
      Map6_IRQ_Cnt = 0;
    }
  }
}

/*===================================================================*/
/*                                                                   */
/*                        Mapper 7 (AOROM)                           */
/*                                                                   */
/*===================================================================*/

/*-------------------------------------------------------------------*/
/*  Initialize Mapper 7                                              */
/*-------------------------------------------------------------------*/
void Map7_Init()
{
  /* Initialize Mapper */
  MapperInit = Map7_Init;

  /* Write to Mapper */
  MapperWrite = Map7_Write;

  /* Write to SRAM */
  MapperSram = Map0_Sram;

  /* Write to APU */
  MapperApu = Map0_Apu;

  /* Read from APU */
  MapperReadApu = Map0_ReadApu;

  /* Callback at VSync */
  MapperVSync = Map0_VSync;

  /* Callback at HSync */
  MapperHSync = Map0_HSync;

  /* Callback at PPU */
  MapperPPU = Map0_PPU;

  /* Callback at Rendering Screen ( 1:BG, 0:Sprite ) */
  MapperRenderScreen = Map0_RenderScreen;

  /* Set SRAM Banks */
  SRAMBANK = SRAM;

  /* Set ROM Banks */
  ROMBANK0 = ROMPAGE( 0 );
  ROMBANK1 = ROMPAGE( 1 );
  ROMBANK2 = ROMPAGE( 2 );
  ROMBANK3 = ROMPAGE( 3 );

  /* Set up wiring of the interrupt pin */
  K6502_Set_Int_Wiring( 1, 1 ); 
}

/*-------------------------------------------------------------------*/
/*  Mapper 7 Write Function                                          */
/*-------------------------------------------------------------------*/
void Map7_Write( WORD wAddr, BYTE byData )
{
  BYTE byBank;

  /* Set ROM Banks */
  byBank = ( byData & 0x07 ) << 2;
  byBank %= ( NesHeader.byRomSize << 1 );

  ROMBANK0 = ROMPAGE( byBank );
  ROMBANK1 = ROMPAGE( byBank + 1 );
  ROMBANK2 = ROMPAGE( byBank + 2 );
  ROMBANK3 = ROMPAGE( byBank + 3 );