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SPC: Switched to fast DSP core (better for development for now)

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This commit is contained in:
Sour 2019-02-17 14:58:48 -05:00
parent 93e8fd9d5e
commit d12a582dbc
2 changed files with 567 additions and 974 deletions
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1355
Core/SPC_DSP.cpp
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186
Core/SPC_DSP.h
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@ -1,4 +1,4 @@
// Highly accurate SNES SPC-700 DSP emulator
// Fast SNES SPC-700 DSP emulator (about 3x speed of accurate one)
// snes_spc 0.9.0
#ifndef SPC_DSP_H
@ -6,14 +6,12 @@
#include "blargg_common.h"
extern "C" { typedef void (*dsp_copy_func_t)( unsigned char** io, void* state, size_t ); }
class SPC_DSP {
public:
typedef BOOST::uint8_t uint8_t;
// Setup
// Initializes DSP and has it use the 64K RAM provided
void init( void* ram_64k );
@ -28,14 +26,14 @@ public:
int sample_count() const;
// Emulation
// Resets DSP to power-on state
void reset();
// Emulates pressing reset switch on SNES
void soft_reset();
// Reads/writes DSP registers. For accuracy, you must first call run()
// Reads/writes DSP registers. For accuracy, you must first call spc_run_dsp()
// to catch the DSP up to present.
int read ( int addr ) const;
void write( int addr, int data );
@ -43,28 +41,23 @@ public:
// Runs DSP for specified number of clocks (~1024000 per second). Every 32 clocks
// a pair of samples is be generated.
void run( int clock_count );
// Sound control
// Mutes voices corresponding to non-zero bits in mask (issues repeated KOFF events).
// Mutes voices corresponding to non-zero bits in mask (overrides VxVOL with 0).
// Reduces emulation accuracy.
enum { voice_count = 8 };
void mute_voices( int mask );
// If true, prevents channels and global volumes from being phase-negated
void disable_surround( bool disable = true );
// State
// Resets DSP and uses supplied values to initialize registers
enum { register_count = 128 };
void load( uint8_t const regs [register_count] );
// Saves/loads exact emulator state
enum { state_size = 640 }; // maximum space needed when saving
typedef dsp_copy_func_t copy_func_t;
void copy_state( unsigned char** io, copy_func_t );
// Returns non-zero if new key-on events occurred since last call
bool check_kon();
// DSP register addresses
// Global registers
@ -93,7 +86,6 @@ public:
enum { extra_size = 16 };
sample_t* extra() { return m.extra; }
sample_t const* out_pos() const { return m.out; }
void disable_surround( bool ) { } // not supported
public:
BLARGG_DISABLE_NOTHROW
@ -107,21 +99,18 @@ public:
struct voice_t
{
int buf [brr_buf_size*2];// decoded samples (twice the size to simplify wrap handling)
int buf_pos; // place in buffer where next samples will be decoded
int* buf_pos; // place in buffer where next samples will be decoded
int interp_pos; // relative fractional position in sample (0x1000 = 1.0)
int brr_addr; // address of current BRR block
int brr_offset; // current decoding offset in BRR block
uint8_t* regs; // pointer to voice's DSP registers
int vbit; // bitmask for voice: 0x01 for voice 0, 0x02 for voice 1, etc.
int kon_delay; // KON delay/current setup phase
env_mode_t env_mode;
int env; // current envelope level
int hidden_env; // used by GAIN mode 7, very obscure quirk
uint8_t t_envx_out;
int volume [2]; // copy of volume from DSP registers, with surround disabled
int enabled; // -1 if enabled, 0 if muted
};
private:
enum { brr_block_size = 9 };
struct state_t
{
uint8_t regs [register_count];
@ -133,53 +122,22 @@ private:
int every_other_sample; // toggles every sample
int kon; // KON value when last checked
int noise;
int counter;
int echo_offset; // offset from ESA in echo buffer
int echo_length; // number of bytes that echo_offset will stop at
int phase; // next clock cycle to run (0-31)
bool kon_check; // set when a new KON occurs
unsigned counters [4];
// Hidden registers also written to when main register is written to
int new_kon;
uint8_t endx_buf;
uint8_t envx_buf;
uint8_t outx_buf;
// Temporary state between clocks
// read once per sample
int t_pmon;
int t_non;
int t_eon;
int t_dir;
int t_koff;
// read a few clocks ahead then used
int t_brr_next_addr;
int t_adsr0;
int t_brr_header;
int t_brr_byte;
int t_srcn;
int t_esa;
int t_echo_enabled;
// internal state that is recalculated every sample
int t_dir_addr;
int t_pitch;
int t_output;
int t_looped;
int t_echo_ptr;
// left/right sums
int t_main_out [2];
int t_echo_out [2];
int t_echo_in [2];
voice_t voices [voice_count];
unsigned* counter_select [32];
// non-emulation state
uint8_t* ram; // 64K shared RAM between DSP and SMP
int mute_mask;
int surround_threshold;
sample_t* out;
sample_t* out_end;
sample_t* out_begin;
@ -188,49 +146,10 @@ private:
state_t m;
void init_counter();
void run_counters();
unsigned read_counter( int rate );
int interpolate( voice_t const* v );
void run_envelope( voice_t* const v );
void decode_brr( voice_t* v );
void misc_27();
void misc_28();
void misc_29();
void misc_30();
void voice_output( voice_t const* v, int ch );
void voice_V1( voice_t* const );
void voice_V2( voice_t* const );
void voice_V3( voice_t* const );
void voice_V3a( voice_t* const );
void voice_V3b( voice_t* const );
void voice_V3c( voice_t* const );
void voice_V4( voice_t* const );
void voice_V5( voice_t* const );
void voice_V6( voice_t* const );
void voice_V7( voice_t* const );
void voice_V8( voice_t* const );
void voice_V9( voice_t* const );
void voice_V7_V4_V1( voice_t* const );
void voice_V8_V5_V2( voice_t* const );
void voice_V9_V6_V3( voice_t* const );
void echo_read( int ch );
int echo_output( int ch );
void echo_write( int ch );
void echo_22();
void echo_23();
void echo_24();
void echo_25();
void echo_26();
void echo_27();
void echo_28();
void echo_29();
void echo_30();
void run_counter( int );
void soft_reset_common();
void write_outline( int addr, int data );
void update_voice_vol( int addr );
};
#include <assert.h>
@ -243,62 +162,51 @@ inline int SPC_DSP::read( int addr ) const
return m.regs [addr];
}
inline void SPC_DSP::update_voice_vol( int addr )
{
int l = (int8_t) m.regs [addr + v_voll];
int r = (int8_t) m.regs [addr + v_volr];
if ( l * r < m.surround_threshold )
{
// signs differ, so negate those that are negative
l ^= l >> 7;
r ^= r >> 7;
}
voice_t& v = m.voices [addr >> 4];
int enabled = v.enabled;
v.volume [0] = l & enabled;
v.volume [1] = r & enabled;
}
inline void SPC_DSP::write( int addr, int data )
{
assert( (unsigned) addr < register_count );
m.regs [addr] = (uint8_t) data;
switch ( addr & 0x0F )
int low = addr & 0x0F;
if ( low < 0x2 ) // voice volumes
{
update_voice_vol( low ^ addr );
}
else if ( low == 0xC )
{
case v_envx:
m.envx_buf = (uint8_t) data;
break;
case v_outx:
m.outx_buf = (uint8_t) data;
break;
case 0x0C:
if ( addr == r_kon )
m.new_kon = (uint8_t) data;
if ( addr == r_endx ) // always cleared, regardless of data written
{
m.endx_buf = 0;
m.regs [r_endx] = 0;
}
break;
}
}
inline void SPC_DSP::mute_voices( int mask ) { m.mute_mask = mask; }
inline bool SPC_DSP::check_kon()
inline void SPC_DSP::disable_surround( bool disable )
{
bool old = m.kon_check;
m.kon_check = 0;
return old;
m.surround_threshold = disable ? 0 : -0x4000;
}
#if !SPC_NO_COPY_STATE_FUNCS
#define SPC_NO_COPY_STATE_FUNCS 1
class SPC_State_Copier {
SPC_DSP::copy_func_t func;
unsigned char** buf;
public:
SPC_State_Copier( unsigned char** p, SPC_DSP::copy_func_t f ) { func = f; buf = p; }
void copy( void* state, size_t size );
int copy_int( int state, int size );
void skip( int count );
void extra();
};
#define SPC_COPY( type, state )\
{\
state = (BOOST::type) copier.copy_int( state, sizeof (BOOST::type) );\
assert( (BOOST::type) state == state );\
}
#endif
#define SPC_LESS_ACCURATE 1
#endif