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path: root/apps/plugins/infones/mapper/InfoNES_Mapper_226.c
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/*===================================================================*/
/*                                                                   */
/*                   Mapper 226 : 76-in-1                            */
/*                                                                   */
/*===================================================================*/

BYTE	Map226_Reg[2];

/*-------------------------------------------------------------------*/
/*  Initialize Mapper 226                                            */
/*-------------------------------------------------------------------*/
void Map226_Init()
{
  /* Initialize Mapper */
  MapperInit = Map226_Init;

  /* Write to Mapper */
  MapperWrite = Map226_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 );

  /* Initialize Registers */
  Map226_Reg[0] = 0;
  Map226_Reg[1] = 0;
  
  /* Set up wiring of the interrupt pin */
  K6502_Set_Int_Wiring( 1, 1 ); 
}

/*-------------------------------------------------------------------*/
/*  Mapper 226 Write Function                                        */
/*-------------------------------------------------------------------*/
void Map226_Write( WORD wAddr, BYTE byData )
{
  if( wAddr & 0x0001 ) {
    Map226_Reg[1] = byData;
  } else {
    Map226_Reg[0] = byData;
  }
  
  if( Map226_Reg[0] & 0x40 ) {
    InfoNES_Mirroring( 1 );
  } else {
    InfoNES_Mirroring( 0 );
  }
  
  BYTE	byBank = ((Map226_Reg[0]&0x1E)>>1)|((Map226_Reg[0]&0x80)>>3)|((Map226_Reg[1]&0x01)<<5);
  
  if( Map226_Reg[0] & 0x20 ) {
    if( Map226_Reg[0] & 0x01 ) {
      ROMBANK0 = ROMPAGE(((byBank<<2)+2) % (NesHeader.byRomSize<<1));
      ROMBANK1 = ROMPAGE(((byBank<<2)+3) % (NesHeader.byRomSize<<1));
      ROMBANK2 = ROMPAGE(((byBank<<2)+2) % (NesHeader.byRomSize<<1));
      ROMBANK3 = ROMPAGE(((byBank<<2)+3) % (NesHeader.byRomSize<<1));
    } else {
      ROMBANK0 = ROMPAGE(((byBank<<2)+0) % (NesHeader.byRomSize<<1));
      ROMBANK1 = ROMPAGE(((byBank<<2)+1) % (NesHeader.byRomSize<<1));
      ROMBANK2 = ROMPAGE(((byBank<<2)+0) % (NesHeader.byRomSize<<1));
      ROMBANK3 = ROMPAGE(((byBank<<2)+1) % (NesHeader.byRomSize<<1));
    }
  } else {
    ROMBANK0 = ROMPAGE(((byBank<<2)+0) % (NesHeader.byRomSize<<1));
    ROMBANK1 = ROMPAGE(((byBank<<2)+1) % (NesHeader.byRomSize<<1));
    ROMBANK2 = ROMPAGE(((byBank<<2)+2) % (NesHeader.byRomSize<<1));
    ROMBANK3 = ROMPAGE(((byBank<<2)+3) % (NesHeader.byRomSize<<1));
  }
}