quickerNES/source/core/nes_data.h

156 lines
4.0 KiB
C

// NES data file block formats
// Nes_Emu 0.7.0
#ifndef NES_DATA_H
#define NES_DATA_H
#include "blargg_common.h"
#include "apu_state.h"
typedef long nes_tag_t;
#if 'ABCD' == '\101\102\103\104'
#define FOUR_CHAR( c ) (\
((c) / '\1\0\0\0' % 0x100 * 0x01000000L) +\
((c) / '\0\1\0\0' % 0x100 * 0x00010000L) +\
((c) / '\0\0\1\0' % 0x100 * 0x00000100L) +\
((c) / '\0\0\0\1' % 0x100 * 0x00000001L)\
)
#else
#if 'ABCD' == 0x41424344
#define FOUR_CHAR( c ) c
#else
#define FOUR_CHAR( c ) (\
((c) / 0x01000000 % 0x100 * 0x00000001) +\
((c) / 0x00010000 % 0x100 * 0x00000100) +\
((c) / 0x00000100 % 0x100 * 0x00010000) +\
((c) / 0x00000001 % 0x100 * 0x01000000)\
)
#endif
#endif
// Binary format of save state blocks. All multi-uint8_t values are stored in little-endian.
nes_tag_t const state_file_tag = FOUR_CHAR('NESS');
// Name of cartridge file in 8-bit characters (UTF-8 preferred) with ".nes" etc *removed*,
// no NUL termination. Yes: "Castlevania (U)". No: "Strider (U).nes".
nes_tag_t const cart_name_tag = FOUR_CHAR('romn');
// CRC-32 of cartridge's PRG and CHR data combined
nes_tag_t const cart_checksum_tag = FOUR_CHAR('csum');
struct nes_block_t
{
uint32_t tag; // ** stored in big-endian
uint32_t size;
void swap();
};
BOOST_STATIC_ASSERT( sizeof (nes_block_t) == 8 );
unsigned long const group_begin_size = 0xffffffff; // group block has this size
nes_tag_t const group_end_tag = FOUR_CHAR('gend'); // group end block has this tag
struct nes_state_t
{
uint16_t timestamp; // CPU clocks * 15 (for NTSC)
uint8_t pal;
uint8_t unused [1];
uint32_t frame_count; // number of frames emulated since power-up
enum { tag = FOUR_CHAR('TIME') };
void swap();
};
BOOST_STATIC_ASSERT( sizeof (nes_state_t) == 8 );
struct joypad_state_t
{
uint32_t joypad_latches [2]; // joypad 1 & 2 shift registers
uint8_t w4016; // strobe
uint8_t unused [3];
enum { tag = FOUR_CHAR('CTRL') };
void swap();
};
BOOST_STATIC_ASSERT( sizeof (joypad_state_t) == 12 );
// Increase this (and let me know) if your mapper requires more state. This only
// sets the size of the in-memory buffer; it doesn't affect the file format at all.
unsigned const max_mapper_state_size = 512; //was 256, needed more for VRC7 audio state
struct mapper_state_t
{
int size;
union {
double align;
uint8_t data [max_mapper_state_size];
};
void write( const void* p, unsigned long s );
int read( void* p, unsigned long s ) const;
};
struct cpu_state_t
{
uint16_t pc;
uint8_t s;
uint8_t p;
uint8_t a;
uint8_t x;
uint8_t y;
uint8_t unused [1];
enum { tag = FOUR_CHAR('CPUR') };
void swap();
};
BOOST_STATIC_ASSERT( sizeof (cpu_state_t) == 8 );
struct ppu_state_t
{
uint8_t w2000; // control
uint8_t w2001; // control
uint8_t r2002; // status
uint8_t w2003; // sprite ram addr
uint8_t r2007; // vram read buffer
uint8_t second_write; // next write to $2005/$2006 is second since last $2002 read
uint16_t vram_addr; // loopy_v
uint16_t vram_temp; // loopy_t
uint8_t pixel_x; // fine-scroll (0-7)
uint8_t unused;
uint8_t palette [0x20]; // entries $10, $14, $18, $1c should be ignored
uint16_t decay_low;
uint16_t decay_high;
uint8_t open_bus;
uint8_t unused2[3];
enum { tag = FOUR_CHAR('PPUR') };
void swap();
};
BOOST_STATIC_ASSERT( sizeof (ppu_state_t) == 20 + 0x20 );
struct mmc1_state_t
{
uint8_t regs [4]; // current registers (5 bits each)
uint8_t bit; // number of bits in buffer (0 to 4)
uint8_t buf; // currently buffered bits (new bits added to bottom)
};
BOOST_STATIC_ASSERT( sizeof (mmc1_state_t) == 6 );
struct mmc3_state_t
{
uint8_t banks [8]; // last writes to $8001 indexed by (mode & 7)
uint8_t mode; // $8000
uint8_t mirror; // $a000
uint8_t sram_mode; // $a001
uint8_t irq_ctr; // internal counter
uint8_t irq_latch; // $c000
uint8_t irq_enabled;// last write was to 0) $e000, 1) $e001
uint8_t irq_flag;
};
BOOST_STATIC_ASSERT( sizeof (mmc3_state_t) == 15 );
#endif