mapper191.cpp

著名的任天堂FC游戏机模拟器VirtuaNes 085版的源码!

//////////////////////////////////////////////////////////////////////////
// Mapper191 SACHEN Super Cartridge Xin1 (Ver.1-9)                      //
//           SACHEN Q-BOY Support                                       //
//////////////////////////////////////////////////////////////////////////

void	Mapper191::Reset()
{
	for( INT i = 0; i < 8; i++ ) {
		reg[i] = 0x00;
	}

	prg0 = 0;
//	prg1 = 1;
	SetBank_CPU();

	chr0 = 0;
	chr1 = 0;
	chr2 = 0;
	chr3 = 0;
	highbank = 0;
	SetBank_PPU();
}

void	Mapper191::WriteLow( WORD addr, BYTE data )
{
	switch( addr ) {
		case	0x4100:
			reg[0]=data;
			break;
		case	0x4101:
			reg[1]=data;
			switch( reg[0] ) {
				case	0:
					chr0=data&7;
					SetBank_PPU();
					break;
				case	1:
					chr1=data&7;
					SetBank_PPU();
					break;
				case	2:
					chr2=data&7;
					SetBank_PPU();
					break;
				case	3:
					chr3=data&7;
					SetBank_PPU();
					break;
				case	4:
					highbank=data&7;
					SetBank_PPU();
					break;
				case	5:
					prg0=data&7;
					SetBank_CPU();
					break;
				case	7:
					if( data & 0x02 ) SetVRAM_Mirror( VRAM_HMIRROR );
					else		  SetVRAM_Mirror( VRAM_VMIRROR );
					break;
			}
			break;
	}
}

void	Mapper191::SetBank_CPU()
{
	SetPROM_32K_Bank( prg0 );
}

void	Mapper191::SetBank_PPU()
{
	if( VROM_1K_SIZE ) {
		SetVROM_1K_Bank( 0, (((highbank<<3)+chr0)<<2)+0 );
		SetVROM_1K_Bank( 1, (((highbank<<3)+chr0)<<2)+1 );
		SetVROM_1K_Bank( 2, (((highbank<<3)+chr1)<<2)+2 );
		SetVROM_1K_Bank( 3, (((highbank<<3)+chr1)<<2)+3 );
		SetVROM_1K_Bank( 4, (((highbank<<3)+chr2)<<2)+0 );
		SetVROM_1K_Bank( 5, (((highbank<<3)+chr2)<<2)+1 );
		SetVROM_1K_Bank( 6, (((highbank<<3)+chr3)<<2)+2 );
		SetVROM_1K_Bank( 7, (((highbank<<3)+chr3)<<2)+3 );
	}
}

void	Mapper191::SaveState( LPBYTE p )
{
	p[0] = prg0;
	p[1] = chr0;
	p[2] = chr1;
 	p[3] = chr2;
	p[4] = chr3;
	p[5] = highbank;
}

void	Mapper191::LoadState( LPBYTE p )
{
	prg0     = p[0];
	chr0     = p[1];
	chr1     = p[2];
	chr2     = p[3];
	chr3     = p[4];
	highbank = p[5];
}