rockbox/lib/rbcodec/codecs/libgme/hes_apu.h
Sean Bartell f40bfc9267 Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
2012-04-25 22:13:20 +02:00

66 lines
1.6 KiB
C

// Turbo Grafx 16 (PC Engine) PSG sound chip emulator
// Game_Music_Emu 0.5.2
#ifndef HES_APU_H
#define HES_APU_H
#include "blargg_common.h"
#include "blargg_source.h"
#include "blip_buffer.h"
enum { amp_range = 0x8000 };
enum { osc_count = 6 }; // 0 <= chan < osc_count
// Registers are at io_addr to io_addr+io_size-1
enum { apu_io_addr = 0x0800 };
enum { apu_io_size = 10 };
struct Hes_Osc
{
byte wave [32];
int delay;
int period;
int phase;
int noise_delay;
byte noise;
unsigned lfsr;
byte control;
byte balance;
byte dac;
short volume [2];
int last_amp [2];
blip_time_t last_time;
struct Blip_Buffer* output [2];
struct Blip_Buffer* outputs [3];
};
void Osc_run_until( struct Hes_Osc* this, struct Blip_Synth* synth, blip_time_t );
struct Hes_Apu {
int latch;
int balance;
struct Blip_Synth synth;
struct Hes_Osc oscs [osc_count];
};
// Init HES apu sound chip
void Apu_init( struct Hes_Apu* this );
// Reset HES apu couns chip
void Apu_reset( struct Hes_Apu* this );
void Apu_osc_output( struct Hes_Apu* this, int index, struct Blip_Buffer* center, struct Blip_Buffer* left, struct Blip_Buffer* right );
// Emulates to time t, then writes data to addr
void Apu_write_data( struct Hes_Apu* this, blip_time_t, int addr, int data );
// Emulates to time t, then subtracts t from the current time.
// OK if previous write call had time slightly after t.
void Apu_end_frame( struct Hes_Apu* this, blip_time_t );
static inline void Apu_volume( struct Hes_Apu* this, int v ) { Synth_volume( &this->synth, (v*9)/5 / osc_count / amp_range ); }
#endif