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// license:BSD-3-Clause
// copyright-holders:Mirko Buffoni,Aaron Giles
/***************************************************************************

    okim6295.h

    OKIM 6295 ADCPM sound chip.

***************************************************************************/

#ifndef MAME_SOUND_OKIM6295_H
#define MAME_SOUND_OKIM6295_H

#pragma once

#include "sound/okiadpcm.h"
#include "dirom.h"

//**************************************************************************
//  TYPE DEFINITIONS
//**************************************************************************


// ======================> okim6295_device

class okim6295_device : public device_t,
						public device_sound_interface,
						public device_rom_interface<18>
{
public:
	enum pin7_state
	{
		PIN7_LOW = 0,
		PIN7_HIGH = 1
	};

	// construction/destruction
	okim6295_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock, pin7_state pin7)
		: okim6295_device(mconfig, tag, owner, clock)
	{
		config_pin7(pin7);
	}
	okim6295_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock);

	// inline configuration helpers
	void config_pin7(pin7_state pin7) { assert(!started()); m_pin7_state = pin7; }

	// runtime configuration
	void set_pin7(int pin7);

	uint8_t read();
	void write(uint8_t command);

protected:
	// device-level overrides
	virtual void device_validity_check(validity_checker &valid) const override;
	virtual void device_start() override;
	virtual void device_reset() override;
	virtual void device_post_load() override;
	virtual void device_clock_changed() override;

	// device_sound_interface overrides
	virtual void sound_stream_update(sound_stream &stream, std::vector<read_stream_view> const &inputs, std::vector<write_stream_view> &outputs) override;

	// device_rom_interface overrides
	virtual void rom_bank_pre_change() override;

	// a single voice
	class okim_voice
	{
	public:
		okim_voice();
		void generate_adpcm(device_rom_interface &rom, write_stream_view &buffer);

		oki_adpcm_state m_adpcm;          // current ADPCM state
		bool            m_playing;
		offs_t          m_base_offset;    // pointer to the base memory location
		uint32_t        m_sample;         // current sample number
		uint32_t        m_count;          // total samples to play
		stream_buffer::sample_t m_volume; // output volume
	};

	// configuration state
	optional_memory_region  m_region;

	// internal state
	static constexpr int OKIM6295_VOICES = 4;

	okim_voice            m_voice[OKIM6295_VOICES];
	int32_t               m_command;
	sound_stream *        m_stream;
	uint8_t               m_pin7_state;

	static const stream_buffer::sample_t s_volume_table[16];
};


// device type definition
DECLARE_DEVICE_TYPE(OKIM6295, okim6295_device)


#endif // MAME_SOUND_OKIM6295_H