/* z80.h: z80 emulation core
   Copyright (c) 1999-2003 Philip Kendall

   $Id: z80.h 4640 2012-01-21 13:26:35Z pak21 $

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with this program; if not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

   Author contact information:

   E-mail: philip-fuse@shadowmagic.org.uk

*/

#ifndef FUSE_Z80_H
#define FUSE_Z80_H

#include "defs.h"

/* Union allowing a register pair to be accessed as bytes or as a word */
typedef union {
#ifdef MSB_FIRST
	struct
	{
		uint8 h, l;
	} b;
#else
	struct
	{
		uint8 l, h;
	} b;
#endif
	uint16 w;
} regpair;

/* What's stored in the main processor */
typedef struct
{
	regpair af, bc, de, hl;
	regpair af_, bc_, de_, hl_;
	regpair ix, iy;
	uint8 i;
	uint16 r; /* The low seven bits of the R register. 16 bits long
			   so it can also act as an RZX instruction counter */
	uint8 r7; /* The high bit of the R register */
	regpair sp, pc;
	uint8 iff1, iff2, im;
	int halted;

	/* Interrupts were enabled at this time; do not accept any interrupts
     until z80_tstates > this value */
	uint64 interrupts_enabled_at;

} processor;

void z80_init(void);
void z80_reset(void);

int z80_interrupt(void);
void z80_nmi(void);

int z80_do_opcode(void);

void z80_enable_interrupts(void);

extern processor z80;
inline uint16 z80_getpc(void) { return z80.pc.w; }
extern const uint8 halfcarry_add_table[];
extern const uint8 halfcarry_sub_table[];
extern const uint8 overflow_add_table[];
extern const uint8 overflow_sub_table[];
extern uint8 sz53_table[];
extern uint8 sz53p_table[];
extern uint8 parity_table[];

extern uint64 z80_tstates, last_z80_tstates;

extern void (*z80_writebyte)(uint16, uint8);
extern uint8 (*z80_readbyte)(uint16);
extern void (*z80_writeport)(uint16, uint8);
extern uint8 (*z80_readport)(uint16);

// Ok, I lied, not a macro!

//Write mem
static INLINE void Z80_WB_MACRO(uint16 A, uint8 V)
{
	z80_tstates += 3;
	z80_writebyte(A, V);
}

// Write port
static INLINE void Z80_WP_MACRO(uint16 A, uint8 V)
{
	z80_tstates += 4;
	z80_writeport(A, V);
}

// Read mem
static INLINE uint8 Z80_RB_MACRO(uint16 A)
{
	z80_tstates += 3;
	return (z80_readbyte(A));
}

// Read port
static INLINE uint8 Z80_RP_MACRO(uint16 A)
{
	z80_tstates += 4;
	return (z80_readport(A));
}

void z80_set_interrupt(int set);

#endif /* #ifndef FUSE_Z80_H */