AxibugEmuOnline/virtuanessrc097-master/NES/Mapper/Mapper043.cpp

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//////////////////////////////////////////////////////////////////////////
// Mapper043 SMB2J //
//////////////////////////////////////////////////////////////////////////
void Mapper043::Reset()
{
irq_enable = 0xFF;
irq_counter = 0;
SetPROM_8K_Bank( 3, 2 );
SetPROM_32K_Bank( 1, 0, 4, 9 );
if( VROM_1K_SIZE ) {
SetVROM_8K_Bank( 0 );
}
}
BYTE Mapper043::ReadLow( WORD addr )
{
if( 0x5000 <= addr && addr < 0x6000 ) {
LPBYTE pPtr = nes->rom->GetPROM();
return pPtr[0x2000*8+0x1000+(addr-0x5000)];
}
return (BYTE)(addr>>8);
}
void Mapper043::ExWrite( WORD addr, BYTE data )
{
if( (addr&0xF0FF) == 0x4022 ) {
switch( data&0x07 ) {
case 0x00:
case 0x02:
case 0x03:
case 0x04:
SetPROM_8K_Bank( 6, 4 );
break;
case 0x01:
SetPROM_8K_Bank( 6, 3 );
break;
case 0x05:
SetPROM_8K_Bank( 6, 7 );
break;
case 0x06:
SetPROM_8K_Bank( 6, 5 );
break;
case 0x07:
SetPROM_8K_Bank( 6, 6 );
break;
}
}
}
void Mapper043::WriteLow( WORD addr, BYTE data )
{
if( (addr&0xF0FF) == 0x4022 ) {
ExWrite( addr, data );
}
}
void Mapper043::Write( WORD addr, BYTE data )
{
if( addr == 0x8122 ) {
if( data&0x03 ) {
irq_enable = 1;
} else {
irq_counter = 0;
irq_enable = 0;
}
nes->cpu->ClrIRQ( IRQ_MAPPER );
}
}
void Mapper043::HSync( INT scanline )
{
nes->cpu->ClrIRQ( IRQ_MAPPER );
if( irq_enable ) {
irq_counter += 341;
if( irq_counter >= 12288 ) {
irq_counter = 0;
// nes->cpu->IRQ();
nes->cpu->SetIRQ( IRQ_MAPPER );
}
}
}
void Mapper043::SaveState( LPBYTE p )
{
p[0] = irq_enable;
*(INT*)&p[1] = irq_counter;
}
void Mapper043::LoadState( LPBYTE p )
{
irq_enable = p[0];
irq_counter = *(INT*)&p[1];
}