text: // license:BSD-3-Clause
  // copyright-holders:R. Belmont, Olivier Galibert, hap
  #ifndef MAME_SOUND_YMF278B_H
  #define MAME_SOUND_YMF278B_H
  
  #pragma once
  
  
  #define YMF278B_STD_CLOCK (33868800)            /* standard clock for OPL4 */
  
  #define MCFG_YMF278B_IRQ_HANDLER(_devcb) \
  	devcb = &downcast<ymf278b_device &>(*device).set_irq_handler(DEVCB_##_devcb);
  
  class ymf278b_device : public device_t, public device_sound_interface, public device_rom_interface
  {
  public:
  	ymf278b_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
  
  	// configuration helpers
  	template <class Object> devcb_base &set_irq_handler(Object &&cb) { return m_irq_handler.set_callback(std::forward<Object>(cb)); }
  
  	DECLARE_READ8_MEMBER( read );
  	DECLARE_WRITE8_MEMBER( write );
  
  protected:
  	// device-level overrides
  	virtual void device_start() override;
  	virtual void device_reset() override;
  	virtual void device_stop() override;
  
  	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
  
  	// sound stream update overrides
  	virtual void sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples) override;
  
  	// device_rom_interface overrides
  	virtual void rom_bank_updated() override;
  
  private:
  	struct YMF278BSlot
  	{
  		int16_t wave;     /* wavetable number */
  		int16_t F_NUMBER; /* frequency */
  		int8_t octave;    /* octave */
  		int8_t preverb;   /* pseudo-reverb */
  		int8_t DAMP;      /* damping */
  		int8_t CH;        /* output channel */
  		int8_t LD;        /* level direct */
  		int8_t TL;        /* total level */
  		int8_t pan;       /* panpot */
  		int8_t LFO;       /* LFO */
  		int8_t VIB;       /* vibrato */
  		int8_t AM;        /* tremolo */
  
  		int8_t AR;        /* attack rate */
  		int8_t D1R;       /* decay 1 rate */
  		int8_t DL;        /* decay level */
  		int8_t D2R;       /* decay 2 rate */
  		int8_t RC;        /* rate correction */
  		int8_t RR;        /* release rate */
  
  		uint32_t step;    /* fixed-point frequency step */
  		uint64_t stepptr; /* fixed-point pointer into the sample */
  
  		int8_t active;    /* channel is playing */
  		int8_t KEY_ON;    /* slot keyed on */
  		int8_t bits;      /* width of the samples */
  		uint32_t startaddr;
  		uint32_t loopaddr;
  		uint32_t endaddr;
  
  		int env_step;
  		uint32_t env_vol;
  		uint32_t env_vol_step;
  		uint32_t env_vol_lim;
  		int8_t env_preverb;
  
  		int num;        /* slot number (for debug only) */
  	};
  
  	int compute_rate(YMF278BSlot *slot, int val);
  	uint32_t compute_decay_env_vol_step(YMF278BSlot *slot, int val);
  	void compute_freq_step(YMF278BSlot *slot);
  	void compute_envelope(YMF278BSlot *slot);
  	void irq_check();
  	void A_w(uint8_t reg, uint8_t data);
  	void B_w(uint8_t reg, uint8_t data);
  	void retrigger_note(YMF278BSlot *slot);
  	void C_w(uint8_t reg, uint8_t data);
  	void timer_busy_start(int is_pcm);
  	void precompute_rate_tables();
  	void register_save_state();
  
  	void update_request() { m_stream_ymf262->update(); }
  
  	static void static_irq_handler(device_t *param, int irq) { }
  	static void static_timer_handler(device_t *param, int c, const attotime &period) { }
  	static void static_update_request(device_t *param, int interval) { downcast<ymf278b_device *>(param)->update_request(); }
  
  	// internal state
  	uint8_t m_pcmregs[256];
  	YMF278BSlot m_slots[24];
  	int8_t m_wavetblhdr;
  	int8_t m_memmode;
  	int32_t m_memadr;
  
  	uint8_t m_status_busy, m_status_ld;
  	emu_timer *m_timer_busy;
  	emu_timer *m_timer_ld;
  	uint8_t m_exp;
  
  	int32_t m_fm_l, m_fm_r;
  	int32_t m_pcm_l, m_pcm_r;
  
  	attotime m_timer_base;
  	uint8_t m_timer_a_count, m_timer_b_count;
  	uint8_t m_enable, m_current_irq;
  	int m_irq_line;
  
  	uint8_t m_port_C, m_port_AB, m_lastport;
  
  	// precomputed tables
  	uint32_t m_lut_ar[64];              // attack rate
  	uint32_t m_lut_dr[64];              // decay rate
  	int32_t m_volume[256*4];            // precalculated attenuation values with some margin for envelope and pan levels
  	int m_pan_left[16],m_pan_right[16]; // pan volume offsets
  	int32_t m_mix_level[8];
  
  	emu_timer *m_timer_a, *m_timer_b;
  	int m_clock;
  
  	sound_stream * m_stream;
  	std::unique_ptr<int32_t[]> m_mix_buffer;
  	devcb_write_line m_irq_handler;
  	uint8_t m_last_fm_data;
  
  	// ymf262
  	void *m_ymf262;
  	sound_stream * m_stream_ymf262;
  };
  
  DECLARE_DEVICE_TYPE(YMF278B, ymf278b_device)
  
  #endif // MAME_SOUND_YMF278B_H
  