cog/Frameworks/GME/gme/Ymz280b_Emu.cpp

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2013-09-28 03:24:46 +00:00
// Game_Music_Emu $vers. http://www.slack.net/~ant/
#include "Ymz280b_Emu.h"
#include "ymz280b.h"
Ymz280b_Emu::Ymz280b_Emu() { chip = 0; }
Ymz280b_Emu::~Ymz280b_Emu()
{
if ( chip ) device_stop_ymz280b( chip );
}
int Ymz280b_Emu::set_rate( int clock_rate )
{
if ( chip )
{
device_stop_ymz280b( chip );
chip = 0;
}
chip = device_start_ymz280b( clock_rate );
if ( !chip )
return 0;
reset();
return clock_rate * 2 / 384;
}
void Ymz280b_Emu::reset()
{
device_reset_ymz280b( chip );
ymz280b_set_mute_mask( chip, 0 );
}
void Ymz280b_Emu::write( int addr, int data )
{
ymz280b_w( chip, 0, addr );
ymz280b_w( chip, 1, data );
}
void Ymz280b_Emu::write_rom( int size, int start, int length, void * data )
{
ymz280b_write_rom( chip, size, start, length, (const UINT8 *) data );
}
void Ymz280b_Emu::mute_voices( int mask )
{
ymz280b_set_mute_mask( chip, mask );
}
void Ymz280b_Emu::run( int pair_count, sample_t* out )
{
stream_sample_t bufL[ 1024 ];
stream_sample_t bufR[ 1024 ];
stream_sample_t * buffers[2] = { bufL, bufR };
while (pair_count > 0)
{
int todo = pair_count;
if (todo > 1024) todo = 1024;
ymz280b_update( chip, buffers, todo );
for (int i = 0; i < todo; i++)
{
int output_l = bufL [i];
int output_r = bufR [i];
output_l += out [0];
output_r += out [1];
if ( (short)output_l != output_l ) output_l = 0x7FFF ^ ( output_l >> 31 );
if ( (short)output_r != output_r ) output_r = 0x7FFF ^ ( output_r >> 31 );
out [0] = output_l;
out [1] = output_r;
out += 2;
}
pair_count -= todo;
}
}