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

    i8243.h

    Intel 8243 Port Expander

    Copyright Aaron Giles

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

#pragma once

#ifndef __I8243_H__
#define __I8243_H__

#include "emu.h"
#include "cpu/mcs48/mcs48.h"



/***************************************************************************
    DEVICE CONFIGURATION MACROS
***************************************************************************/

#define MCFG_I8243_ADD(_tag, _read, _write) \
	MCFG_DEVICE_ADD(_tag, I8243, 0) \
	MCFG_I8243_READHANDLER(_read) \
	MCFG_I8243_WRITEHANDLER(_write) \

#define MCFG_I8243_READHANDLER(_read) \
	i8243_device::static_set_read_handler(*device, _read); \

#define MCFG_I8243_WRITEHANDLER(_write) \
	i8243_device::static_set_write_handler(*device, _write); \

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


// ======================> i8243_device

class i8243_device :  public device_t
{
public:
    // construction/destruction
    i8243_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);

	// inline configuration helpers
	static void static_set_read_handler(device_t &device, read8_device_func callback);
	static void static_set_write_handler(device_t &device, write8_device_func callback);


	UINT8 i8243_p2_r(UINT32 offset);
	void i8243_p2_w(UINT32 offset, UINT8 data);

	void i8243_prog_w(UINT32 offset, UINT8 data);

protected:
    // device-level overrides
    virtual void device_start();
    virtual void device_reset();
    virtual void device_post_load() { }
    virtual void device_clock_changed() { }

private:

	UINT8		m_p[4];				/* 4 ports' worth of data */
	UINT8		m_p2out;			/* port 2 bits that will be returned */
	UINT8		m_p2;				/* most recent port 2 value */
	UINT8		m_opcode;			/* latched opcode */
	UINT8		m_prog;				/* previous PROG state */

	devcb_read8		m_readhandler_cb;
	devcb_write8	m_writehandler_cb;

	devcb_resolved_read8	m_readhandler;
	devcb_resolved_write8	m_writehandler;
};


// device type definition
extern const device_type I8243;



/***************************************************************************
    PROTOTYPES
***************************************************************************/

DECLARE_READ8_DEVICE_HANDLER( i8243_p2_r );
DECLARE_WRITE8_DEVICE_HANDLER( i8243_p2_w );

DECLARE_WRITE8_DEVICE_HANDLER( i8243_prog_w );


#endif  /* __I8243_H__ */