AxibugEmuOnline/References/virtuanessrc097-master/NES/Mapper/Mapper023.cpp

//////////////////////////////////////////////////////////////////////////
// Mapper023  Konami VRC2 type B                                        //
//////////////////////////////////////////////////////////////////////////
void	Mapper023::Reset()
{
	addrmask = 0xFFFF;

	for( INT i = 0; i < 8; i++ ) {
		reg[i] = i;
	}
	reg[8] = 0;

	irq_enable = 0;
	irq_counter = 0;
	irq_latch = 0;
	irq_clock = 0;

	reg[9] = 1;

	SetPROM_32K_Bank( 0, 1, PROM_8K_SIZE-2, PROM_8K_SIZE-1 );
	SetVROM_8K_Bank( 0 );

//	nes->SetRenderMethod( NES::POST_RENDER );

	DWORD	crc = nes->rom->GetPROM_CRC();

	if( crc == 0x93794634		// Akumajou Special Boku Dracula Kun(J)
	 || crc == 0xc7829dae		// Akumajou Special Boku Dracula Kun(T-Eng)
	 || crc == 0xf82dc02f ) {	// Akumajou Special Boku Dracula Kun(T-Eng v1.02)
		addrmask = 0xF00C;
		nes->SetRenderMethod( NES::PRE_ALL_RENDER );
	}
	if( crc == 0xdd53c4ae ) {	// Tiny Toon Adventures(J)
		nes->SetRenderMethod( NES::POST_ALL_RENDER );
	}
}

void	Mapper023::Write( WORD addr, BYTE data )
{
//DEBUGOUT( "MPRWR A=%04X D=%02X L=%3d CYC=%d\n", addr&0xFFFF, data&0xFF, nes->GetScanline(), nes->cpu->GetTotalCycles() );
	switch( addr & addrmask ) {
		case 0x8000:
		case 0x8004:
		case 0x8008:
		case 0x800C:
			if(reg[8]) {
				SetPROM_8K_Bank( 6, data );
			} else {
				SetPROM_8K_Bank( 4, data );
			}
			break;

		case 0x9000:
			if( data != 0xFF ) {
				data &= 0x03;
				if( data == 0 )	     SetVRAM_Mirror( VRAM_VMIRROR );
				else if( data == 1 ) SetVRAM_Mirror( VRAM_HMIRROR );
				else if( data == 2 ) SetVRAM_Mirror( VRAM_MIRROR4L );
				else		     SetVRAM_Mirror( VRAM_MIRROR4H );
			}
			break;

		case 0x9008:
			reg[8] = data & 0x02;
			break;

		case 0xA000:
		case 0xA004:
		case 0xA008:
		case 0xA00C:
			SetPROM_8K_Bank( 5, data );
			break;

		case 0xB000:
			reg[0] = (reg[0] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 0, reg[0] );
			break;
		case 0xB001:
		case 0xB004:
			reg[0] = (reg[0] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 0, reg[0] );
			break;

		case 0xB002:
		case 0xB008:
			reg[1] = (reg[1] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 1, reg[1] );
			break;

		case 0xB003:
		case 0xB00C:
			reg[1] = (reg[1] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 1, reg[1] );
			break;

		case 0xC000:
			reg[2] = (reg[2] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 2, reg[2] );
			break;

		case 0xC001:
		case 0xC004:
			reg[2] = (reg[2] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 2, reg[2] );
			break;

		case 0xC002:
		case 0xC008:
			reg[3] = (reg[3] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 3, reg[3] );
			break;

		case 0xC003:
		case 0xC00C:
			reg[3] = (reg[3] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 3, reg[3] );
			break;

		case 0xD000:
			reg[4] = (reg[4] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 4, reg[4] );
			break;

		case 0xD001:
		case 0xD004:
			reg[4] = (reg[4] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 4, reg[4] );
			break;

		case 0xD002:
		case 0xD008:
			reg[5] = (reg[5] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 5, reg[5] );
			break;

		case 0xD003:
		case 0xD00C:
			reg[5] = (reg[5] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 5, reg[5] );
			break;

		case 0xE000:
			reg[6] = (reg[6] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 6, reg[6] );
			break;

		case 0xE001:
		case 0xE004:
			reg[6] = (reg[6] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 6, reg[6] );
			break;

		case 0xE002:
		case 0xE008:
			reg[7] = (reg[7] & 0xF0) | (data & 0x0F);
			SetVROM_1K_Bank( 7, reg[7] );
			break;

		case 0xE003:
		case 0xE00C:
			reg[7] = (reg[7] & 0x0F) | ((data & 0x0F) << 4);
			SetVROM_1K_Bank( 7, reg[7] );
			break;

		case 0xF000:
			irq_latch = (irq_latch & 0xF0) | (data & 0x0F);
			nes->cpu->ClrIRQ( IRQ_MAPPER );
			break;
		case 0xF004:
			irq_latch = (irq_latch & 0x0F) | ((data & 0x0F) << 4);
			nes->cpu->ClrIRQ( IRQ_MAPPER );
			break;

		case 0xF008:
			irq_enable = data & 0x03;
			irq_counter = irq_latch;
			irq_clock = 0;
			nes->cpu->ClrIRQ( IRQ_MAPPER );
			break;

		case 0xF00C:
			irq_enable = (irq_enable & 0x01) * 3;
			nes->cpu->ClrIRQ( IRQ_MAPPER );
			break;
	}
}

void	Mapper023::Clock( INT cycles )
{
	if( irq_enable & 0x02 ) {
		irq_clock += cycles*3;
		while( irq_clock >= 341 ) {
			irq_clock -= 341;
			irq_counter++;
			if( irq_counter == 0 ) {
				irq_counter = irq_latch;
				nes->cpu->SetIRQ( IRQ_MAPPER );
			}
		}
	}
}

void	Mapper023::SaveState( LPBYTE p )
{
	for( INT i = 0; i < 9; i++ ) {
		p[i] = reg[i];
	}
	p[ 9] = irq_enable;
	p[10] = irq_counter;
	p[11] = irq_latch;
	*(INT*)&p[12] = irq_clock;
}

void	Mapper023::LoadState( LPBYTE p )
{
	for( INT i = 0; i < 9; i++ ) {
		reg[i] = p[i];
	}
	irq_enable  = p[ 9];
	irq_counter = p[10];
	irq_latch   = p[11];
	irq_clock   = *(INT*)&p[12];
}