z80.h

/*
 * Copyright (c) 2019 Nicolas Allemand.
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following condition:  The
 * above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#ifndef Z80_Z80_H_
#define Z80_Z80_H_

#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>

typedef struct z80 z80;
struct z80 {
  uint8_t (*read_byte)(void*, uint16_t);
  void (*write_byte)(void*, uint16_t, uint8_t);
  uint8_t (*port_in)(z80*, uint8_t);
  void (*port_out)(z80*, uint8_t, uint8_t);
  void* userdata;

  unsigned long cyc; /* cycle count (t-states) */

  uint16_t pc, sp, ix, iy; /* special purpose registers */
  uint16_t mem_ptr; /* "wz" register */
  uint8_t a, b, c, d, e, h, l; /* main registers */
  uint8_t a_, b_, c_, d_, e_, h_, l_, f_; /* alternate registers */
  uint8_t i, r; /* interrupt vector, memory refresh */

  /* flags: sign, zero, yf, half-carry, xf, parity/overflow, negative, carry */
  bool sf : 1, zf : 1, yf : 1, hf : 1, xf : 1, pf : 1, nf : 1, cf : 1;

  uint8_t iff_delay;
  uint8_t interrupt_mode;
  uint8_t int_data;
  bool iff1 : 1, iff2 : 1;
  bool halted : 1;
  bool int_pending : 1, nmi_pending : 1;
};

void z80_init(z80* const z);
void z80_step(z80* const z);
void z80_debug_output(z80* const z);
void z80_gen_nmi(z80* const z);
void z80_gen_int(z80* const z, uint8_t state, uint8_t data);

#endif /* Z80_Z80_H_ */