AxibugEmuOnline/References/virtuanessrc097-master/NES/PadEX/EXPAD_TurboFile.cpp
2024-08-05 17:58:53 +08:00

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//////////////////////////////////////////////////////////////////////////
// TurboFile //
//////////////////////////////////////////////////////////////////////////
void EXPAD_TurboFile::Reset()
{
tf_address = 0;
tf_dataold = 0;
tf_databit = 0;
tf_data = 0;
}
BYTE EXPAD_TurboFile::Read4017()
{
return tf_data;
}
void EXPAD_TurboFile::Write4016( BYTE data )
{
INT bank = nes->GetTurboFileBank();
// Reset
if( !(data & 0x02) ) {
tf_address = 0;
tf_databit = 0x01;
}
// Write bit
if( data & 0x04 ) {
ERAM[bank*0x2000+tf_address] &= ~tf_databit;
ERAM[bank*0x2000+tf_address] |= (data&0x01)?tf_databit:0;
}
// Address inc/bit shift
if( (tf_dataold&(~data)) & 0x04 ) {
if( tf_databit == 0x80 ) {
tf_address = (tf_address+1) & 0x1FFF;
tf_databit = 0x01;
} else {
tf_databit <<= 1;
}
}
// Read bit
if( ERAM[bank*0x2000+tf_address] & tf_databit ) {
tf_data = 0x04;
} else {
tf_data = 0x00;
}
tf_dataold = data;
}