nesemu/include/system.h

//
// Created by william on 12/23/23.
//

#include "types.h"
#include "mapper.h"
#include "ppu.h"

#ifndef NESEMULATOR_SYSTEM_H
#define NESEMULATOR_SYSTEM_H

#define FRAME_RATE 60
#define MASTER_CLOCK 21477272   // NTSC NES Master Clock (~21.47 MHz)
#define MASTER_CYCLE_PER_FRAME (MASTER_CLOCK / FRAME_RATE)
#define CPU_CLOCK_DIVISOR 12
#define CPU_CYCLE_PER_FRAME (MASTER_CYCLE_PER_FRAME / CPU_CLOCK_DIVISOR)
#define PPU_CLOCK_DIVISOR 4
#define PPU_CYCLE_PER_CPU_CYCLE (CPU_CLOCK_DIVISOR / PPU_CLOCK_DIVISOR)

#define PPU_REGISTERS_BASE_ADDR 0x2000
#define PPU_REGISTER_OAM_DMA_ADDR 0x4014
#define APU_REGISTERS_COUNT 24

typedef struct system {
    void *rom_header;
    Mapper mapper;
    byte apu_registers[APU_REGISTERS_COUNT];
    unsigned long cycle_count;
} System;

/**
 * Initialize all components of a system.
 */
void system_init();

void system_start();

void system_next_frame();

/**
 * Starts the main loop of a system.
 */
void system_loop();

/**
 * De-initialize the components of a system.
 */
void system_uninit();

unsigned int system_get_cycles();

void system_add_cycles(unsigned int cycles);

Mapper *system_get_mapper();

#endif //NESEMULATOR_SYSTEM_H