mapper134.cpp

著名的任天堂FC游戏机模拟器VirtuaNes 085版的源码!

//////////////////////////////////////////////////////////////////////////
// Mapper133  SACHEN CHEN                                             //
//////////////////////////////////////////////////////////////////////////
void	Mapper134::Reset()
{
	SetPROM_32K_Bank( 0 );
//	SetPROM_16K_Bank( 6, 0 );
//	SetPROM_16K_Bank( 6, 1 );
	SetVROM_8K_Bank( 0 );
}

void	Mapper134::WriteLow( WORD addr, BYTE data )
{
	switch( addr & 0x4101 ) {
		case	0x4100:
			cmd = data & 0x07;
			break;
		case	0x4101:
			switch( cmd ) {
				case 0:	
					prg = 0;
					chr = 3;
					break;
				case 4:
					chr &= 0x3;
					chr |= (data & 0x07) << 2;
					break;
				case 5:
					prg = data & 0x07;
					break;
				case 6:
					chr &= 0x1C;
					chr |= data & 0x3;
					break;
				case 7:
					if( data & 0x01 ) SetVRAM_Mirror( VRAM_HMIRROR );
					else		  SetVRAM_Mirror( VRAM_VMIRROR );
					break;
			}
			break;
	}
	SetPROM_32K_Bank( prg );
//	SetPROM_16K_Bank( 4, (prg<<1)|0 );
//	SetPROM_16K_Bank( 6, (prg<<1)|1 ); 
	SetVROM_8K_Bank( chr );
	CPU_MEM_BANK[addr>>13][addr&0x1FFF] = data;
}

void	Mapper134::SaveState( LPBYTE p )
{
	p[ 0] = cmd;
	p[ 1] = prg;
	p[ 2] = chr;
}

void	Mapper134::LoadState( LPBYTE p )
{
	cmd = p[ 0];
	prg = p[ 1];
	chr = p[ 2];
}