mame/src/devices/machine/at29x.h

// license:BSD-3-Clause
// copyright-holders:Raphael Nabet, Michael Zapf
/*
    ATMEL AT29 family

    Michael Zapf
    August 2015
*/

#ifndef MAME_MACHINE_AT29X_H
#define MAME_MACHINE_AT29X_H

#pragma once


DECLARE_DEVICE_TYPE(AT29C020,  at29c020_device)
DECLARE_DEVICE_TYPE(AT29C040,  at29c040_device)
DECLARE_DEVICE_TYPE(AT29C040A, at29c040a_device)

class at29x_device : public device_t, public device_nvram_interface
{
public:
	DECLARE_READ8_MEMBER( read );
	DECLARE_WRITE8_MEMBER( write );

protected:
	at29x_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock, int memory_size, int device_id, int sector_size);

	virtual void device_start(void) override;
	virtual void device_reset(void) override;
	virtual void device_stop(void) override;
	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;

	void       nvram_default() override;
	void       nvram_read(emu_file &file) override;
	void       nvram_write(emu_file &file) override;

	int        get_sector_number(offs_t address) { return address / m_sector_size; }

	const int  m_memory_size;   // bytes
	int        m_word_width;
	const int  m_device_id;
	const int  m_sector_size;
	int        m_cycle_time;        // ms
	int        m_boot_block_size;
	int        m_version;
	int        m_address_mask;
	int        m_sector_mask;

private:
	enum s_cmd_t
	{
		CMD_0 = 0,
		CMD_1,
		CMD_2
	};

	enum s_pgm_t
	{
		PGM_0 = 0,
		PGM_1,
		PGM_2,
		PGM_3
	};

	void        sync_flags(void);

	std::unique_ptr<uint8_t[]>      m_eememory;

	bool        m_lower_bbl;              // set when lower boot block lockout is enabled
	bool        m_higher_bbl;             // set when upper boot block lockout is enabled
	bool        m_sdp;                    // set when in software data protect mode

	bool        m_id_mode;                // set when in chip id mode
	s_cmd_t     m_cmd;                    // command state
	bool        m_enabling_bbl;           // set when a boot block lockout command is expecting its parameter
	bool        m_long_sequence;          // set if 0x80 command has just been executed (some command require this prefix)
	s_pgm_t     m_pgm;                    // programming state
	bool        m_enabling_sdb;           // set when a sdp enable command is in progress
	bool        m_disabling_sdb;          // set when a sdp disable command is in progress
	bool        m_toggle_bit;             // indicates flashing in progress (toggles for each query)

	std::unique_ptr<uint8_t[]>      m_programming_buffer;
	int         m_programming_last_offset;
	emu_timer*  m_programming_timer;
};

/*
    Variants
*/
class at29c020_device : public at29x_device
{
public:
	at29c020_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock = 0);
};

class at29c040_device : public at29x_device
{
public:
	at29c040_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock = 0);
};

class at29c040a_device : public at29x_device
{
public:
	at29c040a_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock = 0);
};

#endif // MAME_MACHINE_AT29X_H