rlm@0: // SNES SPC-700 APU emulator
rlm@0: 
rlm@0: // snes_spc 0.9.0
rlm@0: #ifndef SNES_SPC_H
rlm@0: #define SNES_SPC_H
rlm@0: 
rlm@0: #include "SPC_DSP.h"
rlm@0: #include "blargg_endian.h"
rlm@0: 
rlm@0: struct SNES_SPC {
rlm@0: public:
rlm@0: 	typedef BOOST::uint8_t uint8_t;
rlm@0: 	
rlm@0: 	// Must be called once before using
rlm@0: 	blargg_err_t init();
rlm@0: 	
rlm@0: 	// Sample pairs generated per second
rlm@0: 	enum { sample_rate = 32000 };
rlm@0: 	
rlm@0: // Emulator use
rlm@0: 	
rlm@0: 	// Sets IPL ROM data. Library does not include ROM data. Most SPC music files
rlm@0: 	// don't need ROM, but a full emulator must provide this.
rlm@0: 	enum { rom_size = 0x40 };
rlm@0: 	void init_rom( uint8_t const rom [rom_size] );
rlm@0: 
rlm@0: 	// Sets destination for output samples
rlm@0: 	typedef short sample_t;
rlm@0: 	void set_output( sample_t* out, int out_size );
rlm@0: 
rlm@0: 	// Number of samples written to output since last set
rlm@0: 	int sample_count() const;
rlm@0: 
rlm@0: 	// Resets SPC to power-on state. This resets your output buffer, so you must
rlm@0: 	// call set_output() after this.
rlm@0: 	void reset();
rlm@0: 
rlm@0: 	// Emulates pressing reset switch on SNES. This resets your output buffer, so
rlm@0: 	// you must call set_output() after this.
rlm@0: 	void soft_reset();
rlm@0: 
rlm@0: 	// 1024000 SPC clocks per second, sample pair every 32 clocks
rlm@0: 	typedef int time_t;
rlm@0: 	enum { clock_rate = 1024000 };
rlm@0: 	enum { clocks_per_sample = 32 };
rlm@0: 	
rlm@0: 	// Emulated port read/write at specified time
rlm@0: 	enum { port_count = 4 };
rlm@0: 	int  read_port ( time_t, int port );
rlm@0: 	void write_port( time_t, int port, int data );
rlm@0: 
rlm@0: 	// Runs SPC to end_time and starts a new time frame at 0
rlm@0: 	void end_frame( time_t end_time );
rlm@0: 	
rlm@0: // Sound control
rlm@0: 	
rlm@0: 	// Mutes voices corresponding to non-zero bits in mask (issues repeated KOFF events).
rlm@0: 	// Reduces emulation accuracy.
rlm@0: 	enum { voice_count = 8 };
rlm@0: 	void mute_voices( int mask );
rlm@0: 	
rlm@0: 	// If true, prevents channels and global volumes from being phase-negated.
rlm@0: 	// Only supported by fast DSP.
rlm@0: 	void disable_surround( bool disable = true );
rlm@0: 	
rlm@0: 	// Sets tempo, where tempo_unit = normal, tempo_unit / 2 = half speed, etc.
rlm@0: 	enum { tempo_unit = 0x100 };
rlm@0: 	void set_tempo( int );
rlm@0: 
rlm@0: // SPC music files
rlm@0: 
rlm@0: 	// Loads SPC data into emulator
rlm@0: 	enum { spc_min_file_size = 0x10180 };
rlm@0: 	enum { spc_file_size     = 0x10200 };
rlm@0: 	blargg_err_t load_spc( void const* in, long size );
rlm@0: 	
rlm@0: 	// Clears echo region. Useful after loading an SPC as many have garbage in echo.
rlm@0: 	void clear_echo();
rlm@0: 
rlm@0: 	// Plays for count samples and write samples to out. Discards samples if out
rlm@0: 	// is NULL. Count must be a multiple of 2 since output is stereo.
rlm@0: 	blargg_err_t play( int count, sample_t* out );
rlm@0: 	
rlm@0: 	// Skips count samples. Several times faster than play() when using fast DSP.
rlm@0: 	blargg_err_t skip( int count );
rlm@0: 	
rlm@0: // State save/load (only available with accurate DSP)
rlm@0: 
rlm@0: #if !SPC_NO_COPY_STATE_FUNCS
rlm@0: 	// Saves/loads state
rlm@0: 	enum { state_size = 67 * 1024L }; // maximum space needed when saving
rlm@0: 	typedef SPC_DSP::copy_func_t copy_func_t;
rlm@0: 	void copy_state( unsigned char** io, copy_func_t );
rlm@0: 	
rlm@0: 	// Writes minimal header to spc_out
rlm@0: 	static void init_header( void* spc_out );
rlm@0: 
rlm@0: 	// Saves emulator state as SPC file data. Writes spc_file_size bytes to spc_out.
rlm@0: 	// Does not set up SPC header; use init_header() for that.
rlm@0: 	void save_spc( void* spc_out );
rlm@0: 
rlm@0: 	// Returns true if new key-on events occurred since last check. Useful for
rlm@0: 	// trimming silence while saving an SPC.
rlm@0: 	bool check_kon();
rlm@0: #endif
rlm@0: 
rlm@0: public:
rlm@0: 	BLARGG_DISABLE_NOTHROW
rlm@0: 	
rlm@0: 	typedef BOOST::uint16_t uint16_t;
rlm@0: 	
rlm@0: 	// Time relative to m_spc_time. Speeds up code a bit by eliminating need to
rlm@0: 	// constantly add m_spc_time to time from CPU. CPU uses time that ends at
rlm@0: 	// 0 to eliminate reloading end time every instruction. It pays off.
rlm@0: 	typedef int rel_time_t;
rlm@0: 	
rlm@0: 	struct Timer
rlm@0: 	{
rlm@0: 		rel_time_t next_time; // time of next event
rlm@0: 		int prescaler;
rlm@0: 		int period;
rlm@0: 		int divider;
rlm@0: 		int enabled;
rlm@0: 		int counter;
rlm@0: 	};
rlm@0: 	enum { reg_count = 0x10 };
rlm@0: 	enum { timer_count = 3 };
rlm@0: 	enum { extra_size = SPC_DSP::extra_size };
rlm@0: 	
rlm@0: 	enum { signature_size = 35 };
rlm@0: 	
rlm@0: private:
rlm@0: 	SPC_DSP dsp;
rlm@0: 	
rlm@0: 	#if SPC_LESS_ACCURATE
rlm@0: 		static signed char const reg_times_ [256];
rlm@0: 		signed char reg_times [256];
rlm@0: 	#endif
rlm@0: 	
rlm@0: 	struct state_t
rlm@0: 	{
rlm@0: 		Timer timers [timer_count];
rlm@0: 		
rlm@0: 		uint8_t smp_regs [2] [reg_count];
rlm@0: 		
rlm@0: 		struct
rlm@0: 		{
rlm@0: 			int pc;
rlm@0: 			int a;
rlm@0: 			int x;
rlm@0: 			int y;
rlm@0: 			int psw;
rlm@0: 			int sp;
rlm@0: 		} cpu_regs;
rlm@0: 		
rlm@0: 		rel_time_t  dsp_time;
rlm@0: 		time_t      spc_time;
rlm@0: 		bool        echo_accessed;
rlm@0: 		
rlm@0: 		int         tempo;
rlm@0: 		int         skipped_kon;
rlm@0: 		int         skipped_koff;
rlm@0: 		const char* cpu_error;
rlm@0: 		
rlm@0: 		int         extra_clocks;
rlm@0: 		sample_t*   buf_begin;
rlm@0: 		sample_t const* buf_end;
rlm@0: 		sample_t*   extra_pos;
rlm@0: 		sample_t    extra_buf [extra_size];
rlm@0: 		
rlm@0: 		int         rom_enabled;
rlm@0: 		uint8_t     rom    [rom_size];
rlm@0: 		uint8_t     hi_ram [rom_size];
rlm@0: 		
rlm@0: 		unsigned char cycle_table [256];
rlm@0: 		
rlm@0: 		struct
rlm@0: 		{
rlm@0: 			// padding to neutralize address overflow
rlm@0: 			union {
rlm@0: 				uint8_t padding1 [0x100];
rlm@0: 				uint16_t align; // makes compiler align data for 16-bit access
rlm@0: 			} padding1 [1];
rlm@0: 			uint8_t ram      [0x10000];
rlm@0: 			uint8_t padding2 [0x100];
rlm@0: 		} ram;
rlm@0: 	};
rlm@0: 	state_t m;
rlm@0: 	
rlm@0: 	enum { rom_addr = 0xFFC0 };
rlm@0: 	
rlm@0: 	enum { skipping_time = 127 };
rlm@0: 	
rlm@0: 	// Value that padding should be filled with
rlm@0: 	enum { cpu_pad_fill = 0xFF };
rlm@0: 	
rlm@0: 	enum {
rlm@0:         r_test     = 0x0, r_control  = 0x1,
rlm@0:         r_dspaddr  = 0x2, r_dspdata  = 0x3,
rlm@0:         r_cpuio0   = 0x4, r_cpuio1   = 0x5,
rlm@0:         r_cpuio2   = 0x6, r_cpuio3   = 0x7,
rlm@0:         r_f8       = 0x8, r_f9       = 0x9,
rlm@0:         r_t0target = 0xA, r_t1target = 0xB, r_t2target = 0xC,
rlm@0:         r_t0out    = 0xD, r_t1out    = 0xE, r_t2out    = 0xF
rlm@0: 	};
rlm@0: 	
rlm@0: 	void timers_loaded();
rlm@0: 	void enable_rom( int enable );
rlm@0: 	void reset_buf();
rlm@0: 	void save_extra();
rlm@0: 	void load_regs( uint8_t const in [reg_count] );
rlm@0: 	void ram_loaded();
rlm@0: 	void regs_loaded();
rlm@0: 	void reset_time_regs();
rlm@0: 	void reset_common( int timer_counter_init );
rlm@0: 	
rlm@0: 	Timer* run_timer_      ( Timer* t, rel_time_t );
rlm@0: 	Timer* run_timer       ( Timer* t, rel_time_t );
rlm@0: 	int dsp_read           ( rel_time_t );
rlm@0: 	void dsp_write         ( int data, rel_time_t );
rlm@0: 	void cpu_write_smp_reg_( int data, rel_time_t, int addr );
rlm@0: 	void cpu_write_smp_reg ( int data, rel_time_t, int addr );
rlm@0: 	void cpu_write_high    ( int data, int i, rel_time_t );
rlm@0: 	void cpu_write         ( int data, int addr, rel_time_t );
rlm@0: 	int cpu_read_smp_reg   ( int i, rel_time_t );
rlm@0: 	int cpu_read           ( int addr, rel_time_t );
rlm@0: 	unsigned CPU_mem_bit   ( uint8_t const* pc, rel_time_t );
rlm@0: 	
rlm@0: 	bool check_echo_access ( int addr );
rlm@0: 	uint8_t* run_until_( time_t end_time );
rlm@0: 	
rlm@0: 	struct spc_file_t
rlm@0: 	{
rlm@0: 		char    signature [signature_size];
rlm@0: 		uint8_t has_id666;
rlm@0: 		uint8_t version;
rlm@0: 		uint8_t pcl, pch;
rlm@0: 		uint8_t a;
rlm@0: 		uint8_t x;
rlm@0: 		uint8_t y;
rlm@0: 		uint8_t psw;
rlm@0: 		uint8_t sp;
rlm@0: 		char    text [212];
rlm@0: 		uint8_t ram [0x10000];
rlm@0: 		uint8_t dsp [128];
rlm@0: 		uint8_t unused [0x40];
rlm@0: 		uint8_t ipl_rom [0x40];
rlm@0: 	};
rlm@0: 
rlm@0: 	static char const signature [signature_size + 1];
rlm@0: 	
rlm@0: 	void save_regs( uint8_t out [reg_count] );
rlm@0: };
rlm@0: 
rlm@0: #include <assert.h>
rlm@0: 
rlm@0: inline int SNES_SPC::sample_count() const { return (m.extra_clocks >> 5) * 2; }
rlm@0: 
rlm@0: inline int SNES_SPC::read_port( time_t t, int port )
rlm@0: {
rlm@0: 	assert( (unsigned) port < port_count );
rlm@0: 	return run_until_( t ) [port];
rlm@0: }
rlm@0: 
rlm@0: inline void SNES_SPC::write_port( time_t t, int port, int data )
rlm@0: {
rlm@0: 	assert( (unsigned) port < port_count );
rlm@0: 	run_until_( t ) [0x10 + port] = data;
rlm@0: }
rlm@0: 
rlm@0: inline void SNES_SPC::mute_voices( int mask ) { dsp.mute_voices( mask ); }
rlm@0: 	
rlm@0: inline void SNES_SPC::disable_surround( bool disable ) { dsp.disable_surround( disable ); }
rlm@0: 
rlm@0: #if !SPC_NO_COPY_STATE_FUNCS
rlm@0: inline bool SNES_SPC::check_kon() { return dsp.check_kon(); }
rlm@0: #endif
rlm@0: 
rlm@0: #endif