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Diffstat (limited to 'gme/Sms_Apu.h')
-rw-r--r-- | gme/Sms_Apu.h | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/gme/Sms_Apu.h b/gme/Sms_Apu.h new file mode 100644 index 00000000..3c11a9c3 --- /dev/null +++ b/gme/Sms_Apu.h @@ -0,0 +1,75 @@ +// Sega Master System SN76489 PSG sound chip emulator + +// Sms_Snd_Emu 0.1.4 +#ifndef SMS_APU_H +#define SMS_APU_H + +#include "Sms_Oscs.h" + +class Sms_Apu { +public: + // Set overall volume of all oscillators, where 1.0 is full volume + void volume( double ); + + // Set treble equalization + void treble_eq( const blip_eq_t& ); + + // Outputs can be assigned to a single buffer for mono output, or to three + // buffers for stereo output (using Stereo_Buffer to do the mixing). + + // Assign all oscillator outputs to specified buffer(s). If buffer + // is NULL, silences all oscillators. + void output( Blip_Buffer* mono ); + void output( Blip_Buffer* center, Blip_Buffer* left, Blip_Buffer* right ); + + // Assign single oscillator output to buffer(s). Valid indicies are 0 to 3, + // which refer to Square 1, Square 2, Square 3, and Noise. If buffer is NULL, + // silences oscillator. + enum { osc_count = 4 }; + void osc_output( int index, Blip_Buffer* mono ); + void osc_output( int index, Blip_Buffer* center, Blip_Buffer* left, Blip_Buffer* right ); + + // Reset oscillators and internal state + void reset( unsigned noise_feedback = 0, int noise_width = 0 ); + + // Write GameGear left/right assignment byte + void write_ggstereo( blip_time_t, int ); + + // Write to data port + void write_data( blip_time_t, int ); + + // Run all oscillators up to specified time, end current frame, then + // start a new frame at time 0. + void end_frame( blip_time_t ); + +public: + Sms_Apu(); + ~Sms_Apu(); +private: + // noncopyable + Sms_Apu( const Sms_Apu& ); + Sms_Apu& operator = ( const Sms_Apu& ); + + Sms_Osc* oscs [osc_count]; + Sms_Square squares [3]; + Sms_Square::Synth square_synth; // used by squares + blip_time_t last_time; + int latch; + Sms_Noise noise; + unsigned noise_feedback; + unsigned looped_feedback; + + void run_until( blip_time_t ); +}; + +struct sms_apu_state_t +{ + unsigned char regs [8] [2]; + unsigned char latch; +}; + +inline void Sms_Apu::output( Blip_Buffer* b ) { output( b, b, b ); } + +inline void Sms_Apu::osc_output( int i, Blip_Buffer* b ) { osc_output( i, b, b, b ); } + +#endif |