snes9x/apu/SNES_SPC.h

296 lines
7.6 KiB
C++

// SNES SPC-700 APU emulator
// snes_spc 0.9.0
#ifndef SNES_SPC_H
#define SNES_SPC_H
#include "SPC_DSP.h"
#include "blargg_endian.h"
struct SNES_SPC {
public:
typedef BOOST::uint8_t uint8_t;
// Must be called once before using
blargg_err_t init();
// Sample pairs generated per second
enum { sample_rate = 32000 };
// Emulator use
// Sets IPL ROM data. Library does not include ROM data. Most SPC music files
// don't need ROM, but a full emulator must provide this.
enum { rom_size = 0x40 };
void init_rom( uint8_t const rom [rom_size] );
// Sets destination for output samples
typedef short sample_t;
void set_output( sample_t* out, int out_size );
// Number of samples written to output since last set
int sample_count() const;
// Resets SPC to power-on state. This resets your output buffer, so you must
// call set_output() after this.
void reset();
// Emulates pressing reset switch on SNES. This resets your output buffer, so
// you must call set_output() after this.
void soft_reset();
// 1024000 SPC clocks per second, sample pair every 32 clocks
typedef int time_t;
enum { clock_rate = 1024000 };
enum { clocks_per_sample = 32 };
// Emulated port read/write at specified time
enum { port_count = 4 };
int read_port ( time_t, int port );
void write_port( time_t, int port, int data );
// Runs SPC to end_time and starts a new time frame at 0
void end_frame( time_t end_time );
// Sound control
// Mutes voices corresponding to non-zero bits in mask (issues repeated KOFF events).
// Reduces emulation accuracy.
enum { voice_count = 8 };
void mute_voices( int mask );
// If true, prevents channels and global volumes from being phase-negated.
// Only supported by fast DSP.
void disable_surround( bool disable = true );
// Sets tempo, where tempo_unit = normal, tempo_unit / 2 = half speed, etc.
enum { tempo_unit = 0x100 };
void set_tempo( int );
// SPC music files
// Loads SPC data into emulator
enum { spc_min_file_size = 0x10180 };
enum { spc_file_size = 0x10200 };
blargg_err_t load_spc( void const* in, long size );
// Clears echo region. Useful after loading an SPC as many have garbage in echo.
void clear_echo();
// Plays for count samples and write samples to out. Discards samples if out
// is NULL. Count must be a multiple of 2 since output is stereo.
blargg_err_t play( int count, sample_t* out );
// Skips count samples. Several times faster than play() when using fast DSP.
blargg_err_t skip( int count );
// State save/load (only available with accurate DSP)
#if !SPC_NO_COPY_STATE_FUNCS
// Saves/loads state
enum { state_size = 68 * 1024L }; // maximum space needed when saving
typedef SPC_DSP::copy_func_t copy_func_t;
void copy_state( unsigned char** io, copy_func_t );
// Writes minimal header to spc_out
static void init_header( void* spc_out );
// Saves emulator state as SPC file data. Writes spc_file_size bytes to spc_out.
// Does not set up SPC header; use init_header() for that.
void save_spc( void* spc_out );
// Returns true if new key-on events occurred since last check. Useful for
// trimming silence while saving an SPC.
bool check_kon();
#endif
//// Snes9x Accessor
void spc_allow_time_overflow( bool );
void dsp_set_spc_snapshot_callback( void (*callback) (void) );
void dsp_dump_spc_snapshot( void );
void dsp_set_stereo_switch( int );
uint8_t dsp_reg_value( int, int );
int dsp_envx_value( int );
public:
BLARGG_DISABLE_NOTHROW
typedef BOOST::uint16_t uint16_t;
// Time relative to m_spc_time. Speeds up code a bit by eliminating need to
// constantly add m_spc_time to time from CPU. CPU uses time that ends at
// 0 to eliminate reloading end time every instruction. It pays off.
typedef int rel_time_t;
struct Timer
{
rel_time_t next_time; // time of next event
int prescaler;
int period;
int divider;
int enabled;
int counter;
};
enum { reg_count = 0x10 };
enum { timer_count = 3 };
enum { extra_size = SPC_DSP::extra_size };
enum { signature_size = 35 };
private:
SPC_DSP dsp;
#if SPC_LESS_ACCURATE
static signed char const reg_times_ [256];
signed char reg_times [256];
#endif
struct state_t
{
Timer timers [timer_count];
uint8_t smp_regs [2] [reg_count];
struct
{
int pc;
int a;
int x;
int y;
int psw;
int sp;
} cpu_regs;
rel_time_t dsp_time;
time_t spc_time;
bool echo_accessed;
int tempo;
int skipped_kon;
int skipped_koff;
const char* cpu_error;
int extra_clocks;
sample_t* buf_begin;
sample_t const* buf_end;
sample_t* extra_pos;
sample_t extra_buf [extra_size];
int rom_enabled;
uint8_t rom [rom_size];
uint8_t hi_ram [rom_size];
unsigned char cycle_table [256];
struct
{
// padding to neutralize address overflow
union {
uint8_t padding1 [0x100];
uint16_t align; // makes compiler align data for 16-bit access
} padding1 [1];
uint8_t ram [0x10000];
uint8_t padding2 [0x100];
} ram;
};
state_t m;
enum { rom_addr = 0xFFC0 };
enum { skipping_time = 127 };
// Value that padding should be filled with
enum { cpu_pad_fill = 0xFF };
enum {
r_test = 0x0, r_control = 0x1,
r_dspaddr = 0x2, r_dspdata = 0x3,
r_cpuio0 = 0x4, r_cpuio1 = 0x5,
r_cpuio2 = 0x6, r_cpuio3 = 0x7,
r_f8 = 0x8, r_f9 = 0x9,
r_t0target = 0xA, r_t1target = 0xB, r_t2target = 0xC,
r_t0out = 0xD, r_t1out = 0xE, r_t2out = 0xF
};
void timers_loaded();
void enable_rom( int enable );
void reset_buf();
void save_extra();
void load_regs( uint8_t const in [reg_count] );
void ram_loaded();
void regs_loaded();
void reset_time_regs();
void reset_common( int timer_counter_init );
Timer* run_timer_ ( Timer* t, rel_time_t );
Timer* run_timer ( Timer* t, rel_time_t );
int dsp_read ( rel_time_t );
void dsp_write ( int data, rel_time_t );
void cpu_write_smp_reg_( int data, rel_time_t, int addr );
void cpu_write_smp_reg ( int data, rel_time_t, int addr );
void cpu_write_high ( int data, int i, rel_time_t );
void cpu_write ( int data, int addr, rel_time_t );
int cpu_read_smp_reg ( int i, rel_time_t );
int cpu_read ( int addr, rel_time_t );
unsigned CPU_mem_bit ( uint8_t const* pc, rel_time_t );
bool check_echo_access ( int addr );
uint8_t* run_until_( time_t end_time );
struct spc_file_t
{
char signature [signature_size];
uint8_t has_id666;
uint8_t version;
uint8_t pcl, pch;
uint8_t a;
uint8_t x;
uint8_t y;
uint8_t psw;
uint8_t sp;
char text [212];
uint8_t ram [0x10000];
uint8_t dsp [128];
uint8_t unused [0x40];
uint8_t ipl_rom [0x40];
};
static char const signature [signature_size + 1];
void save_regs( uint8_t out [reg_count] );
// Snes9x timing hack
bool allow_time_overflow;
};
#include <assert.h>
inline int SNES_SPC::sample_count() const { return (m.extra_clocks >> 5) * 2; }
inline int SNES_SPC::read_port( time_t t, int port )
{
assert( (unsigned) port < port_count );
return run_until_( t ) [port];
}
inline void SNES_SPC::write_port( time_t t, int port, int data )
{
assert( (unsigned) port < port_count );
run_until_( t ) [0x10 + port] = data;
m.ram.ram [0xF4 + port] = data;
}
inline void SNES_SPC::mute_voices( int mask ) { dsp.mute_voices( mask ); }
inline void SNES_SPC::disable_surround( bool disable ) { dsp.disable_surround( disable ); }
#if !SPC_NO_COPY_STATE_FUNCS
inline bool SNES_SPC::check_kon() { return dsp.check_kon(); }
#endif
inline void SNES_SPC::spc_allow_time_overflow( bool allow ) { allow_time_overflow = allow; }
#endif