cog/Frameworks/GME/gme/Nes_Namco_Apu.h

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// Namco 106 sound chip emulator
// Nes_Snd_Emu $vers
#ifndef NES_NAMCO_APU_H
#define NES_NAMCO_APU_H
#include "blargg_common.h"
#include "Blip_Buffer.h"
struct namco_state_t;
class Nes_Namco_Apu {
public:
// See Nes_Apu.h for reference.
void volume( double );
void treble_eq( const blip_eq_t& );
void set_output( Blip_Buffer* );
enum { osc_count = 8 };
void set_output( int index, Blip_Buffer* );
void reset();
void end_frame( blip_time_t );
// Read/write data register is at 0x4800
enum { data_reg_addr = 0x4800 };
void write_data( blip_time_t, int );
int read_data();
// Write-only address register is at 0xF800
enum { addr_reg_addr = 0xF800 };
void write_addr( int );
// to do: implement save/restore
void save_state( namco_state_t* out ) const;
void load_state( namco_state_t const& );
public:
Nes_Namco_Apu();
BLARGG_DISABLE_NOTHROW
private:
// noncopyable
Nes_Namco_Apu( const Nes_Namco_Apu& );
Nes_Namco_Apu& operator = ( const Nes_Namco_Apu& );
struct Namco_Osc {
int delay;
Blip_Buffer* output;
short last_amp;
};
Namco_Osc oscs [osc_count];
blip_time_t last_time;
int addr_reg;
enum { reg_count = 0x80 };
BOOST::uint8_t reg [reg_count];
Blip_Synth_Norm synth;
BOOST::uint8_t& access();
void run_until( blip_time_t );
};
/*
struct namco_state_t
{
BOOST::uint8_t regs [0x80];
BOOST::uint8_t addr;
BOOST::uint8_t unused;
BOOST::uint8_t positions [8];
BOOST::uint32_t delays [8];
};
*/
inline BOOST::uint8_t& Nes_Namco_Apu::access()
{
int addr = addr_reg & 0x7F;
if ( addr_reg & 0x80 )
addr_reg = (addr + 1) | 0x80;
return reg [addr];
}
inline void Nes_Namco_Apu::volume( double v ) { synth.volume( 0.10 / osc_count / 15 * v ); }
inline void Nes_Namco_Apu::treble_eq( const blip_eq_t& eq ) { synth.treble_eq( eq ); }
inline void Nes_Namco_Apu::write_addr( int v ) { addr_reg = v; }
inline int Nes_Namco_Apu::read_data() { return access(); }
inline void Nes_Namco_Apu::set_output( int i, Blip_Buffer* buf )
{
assert( (unsigned) i < osc_count );
oscs [i].output = buf;
}
inline void Nes_Namco_Apu::write_data( blip_time_t time, int data )
{
run_until( time );
access() = data;
}
#endif