snes9x/bsx.cpp

/***********************************************************************************
  Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.

  (c) Copyright 1996 - 2002  Gary Henderson (gary.henderson@ntlworld.com),
                             Jerremy Koot (jkoot@snes9x.com)

  (c) Copyright 2002 - 2004  Matthew Kendora

  (c) Copyright 2002 - 2005  Peter Bortas (peter@bortas.org)

  (c) Copyright 2004 - 2005  Joel Yliluoma (http://iki.fi/bisqwit/)

  (c) Copyright 2001 - 2006  John Weidman (jweidman@slip.net)

  (c) Copyright 2002 - 2006  funkyass (funkyass@spam.shaw.ca),
                             Kris Bleakley (codeviolation@hotmail.com)

  (c) Copyright 2002 - 2010  Brad Jorsch (anomie@users.sourceforge.net),
                             Nach (n-a-c-h@users.sourceforge.net),

  (c) Copyright 2002 - 2011  zones (kasumitokoduck@yahoo.com)

  (c) Copyright 2006 - 2007  nitsuja

  (c) Copyright 2009 - 2017  BearOso,
                             OV2

  (c) Copyright 2017         qwertymodo

  (c) Copyright 2011 - 2017  Hans-Kristian Arntzen,
                             Daniel De Matteis
                             (Under no circumstances will commercial rights be given)


  BS-X C emulator code
  (c) Copyright 2005 - 2006  Dreamer Nom,
                             zones

  C4 x86 assembler and some C emulation code
  (c) Copyright 2000 - 2003  _Demo_ (_demo_@zsnes.com),
                             Nach,
                             zsKnight (zsknight@zsnes.com)

  C4 C++ code
  (c) Copyright 2003 - 2006  Brad Jorsch,
                             Nach

  DSP-1 emulator code
  (c) Copyright 1998 - 2006  _Demo_,
                             Andreas Naive (andreasnaive@gmail.com),
                             Gary Henderson,
                             Ivar (ivar@snes9x.com),
                             John Weidman,
                             Kris Bleakley,
                             Matthew Kendora,
                             Nach,
                             neviksti (neviksti@hotmail.com)

  DSP-2 emulator code
  (c) Copyright 2003         John Weidman,
                             Kris Bleakley,
                             Lord Nightmare (lord_nightmare@users.sourceforge.net),
                             Matthew Kendora,
                             neviksti

  DSP-3 emulator code
  (c) Copyright 2003 - 2006  John Weidman,
                             Kris Bleakley,
                             Lancer,
                             z80 gaiden

  DSP-4 emulator code
  (c) Copyright 2004 - 2006  Dreamer Nom,
                             John Weidman,
                             Kris Bleakley,
                             Nach,
                             z80 gaiden

  OBC1 emulator code
  (c) Copyright 2001 - 2004  zsKnight,
                             pagefault (pagefault@zsnes.com),
                             Kris Bleakley
                             Ported from x86 assembler to C by sanmaiwashi

  SPC7110 and RTC C++ emulator code used in 1.39-1.51
  (c) Copyright 2002         Matthew Kendora with research by
                             zsKnight,
                             John Weidman,
                             Dark Force

  SPC7110 and RTC C++ emulator code used in 1.52+
  (c) Copyright 2009         byuu,
                             neviksti

  S-DD1 C emulator code
  (c) Copyright 2003         Brad Jorsch with research by
                             Andreas Naive,
                             John Weidman

  S-RTC C emulator code
  (c) Copyright 2001 - 2006  byuu,
                             John Weidman

  ST010 C++ emulator code
  (c) Copyright 2003         Feather,
                             John Weidman,
                             Kris Bleakley,
                             Matthew Kendora

  Super FX x86 assembler emulator code
  (c) Copyright 1998 - 2003  _Demo_,
                             pagefault,
                             zsKnight

  Super FX C emulator code
  (c) Copyright 1997 - 1999  Ivar,
                             Gary Henderson,
                             John Weidman

  Sound emulator code used in 1.5-1.51
  (c) Copyright 1998 - 2003  Brad Martin
  (c) Copyright 1998 - 2006  Charles Bilyue'

  Sound emulator code used in 1.52+
  (c) Copyright 2004 - 2007  Shay Green (gblargg@gmail.com)

  S-SMP emulator code used in 1.54+
  (c) Copyright 2016         byuu

  SH assembler code partly based on x86 assembler code
  (c) Copyright 2002 - 2004  Marcus Comstedt (marcus@mc.pp.se)

  2xSaI filter
  (c) Copyright 1999 - 2001  Derek Liauw Kie Fa

  HQ2x, HQ3x, HQ4x filters
  (c) Copyright 2003         Maxim Stepin (maxim@hiend3d.com)

  NTSC filter
  (c) Copyright 2006 - 2007  Shay Green

  GTK+ GUI code
  (c) Copyright 2004 - 2017  BearOso

  Win32 GUI code
  (c) Copyright 2003 - 2006  blip,
                             funkyass,
                             Matthew Kendora,
                             Nach,
                             nitsuja
  (c) Copyright 2009 - 2017  OV2

  Mac OS GUI code
  (c) Copyright 1998 - 2001  John Stiles
  (c) Copyright 2001 - 2011  zones

  Libretro port
  (c) Copyright 2011 - 2017  Hans-Kristian Arntzen,
                             Daniel De Matteis
                             (Under no circumstances will commercial rights be given)


  Specific ports contains the works of other authors. See headers in
  individual files.


  Snes9x homepage: http://www.snes9x.com/

  Permission to use, copy, modify and/or distribute Snes9x in both binary
  and source form, for non-commercial purposes, is hereby granted without
  fee, providing that this license information and copyright notice appear
  with all copies and any derived work.

  This software is provided 'as-is', without any express or implied
  warranty. In no event shall the authors be held liable for any damages
  arising from the use of this software or it's derivatives.

  Snes9x is freeware for PERSONAL USE only. Commercial users should
  seek permission of the copyright holders first. Commercial use includes,
  but is not limited to, charging money for Snes9x or software derived from
  Snes9x, including Snes9x or derivatives in commercial game bundles, and/or
  using Snes9x as a promotion for your commercial product.

  The copyright holders request that bug fixes and improvements to the code
  should be forwarded to them so everyone can benefit from the modifications
  in future versions.

  Super NES and Super Nintendo Entertainment System are trademarks of
  Nintendo Co., Limited and its subsidiary companies.
 ***********************************************************************************/

// Dreamer Nom wrote:
// Large thanks to John Weidman for all his initial research
// Thanks to Seph3 for his modem notes


#include "snes9x.h"
#include "memmap.h"
#include "display.h"
#include <math.h>

//#define BSX_DEBUG

#define BIOS_SIZE	0x100000
#define FLASH_SIZE	0x100000
#define PSRAM_SIZE	0x80000

#define Map			Memory.Map
#define BlockIsRAM	Memory.BlockIsRAM
#define BlockIsROM	Memory.BlockIsROM
#define RAM			Memory.RAM
#define SRAM		Memory.SRAM
#define PSRAM		Memory.BSRAM
#define BIOSROM		Memory.BIOSROM
#define MAP_BSX		Memory.MAP_BSX
#define MAP_CPU		Memory.MAP_CPU
#define MAP_PPU		Memory.MAP_PPU
#define MAP_NONE	Memory.MAP_NONE

#define BSXPPUBASE	0x2180

struct SBSX_RTC
{
	int year;
	int month;
	int dayweek;
	int day;
	int	hours;
	int	minutes;
	int	seconds;
	int	ticks;
};

static struct SBSX_RTC	BSX_RTC;

// flash card vendor information
static const uint8	flashcard[20] =
{
	0x4D, 0x00, 0x50, 0x00,	// vendor id
	0x00, 0x00,				// ?
	0x1A, 0x00,				// 2MB Flash (1MB = 0x2A)
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

static const uint8	init2192[32] =	// FIXME
{
	00, 00, 00, 00, 00,		// unknown
	01, 01, 00, 00, 00,
	00,						// seconds (?)
	00,						// minutes
	00,						// hours
	10, 10, 10, 10, 10,		// unknown
	10, 10, 10, 10, 10,		// dummy
	00, 00, 00, 00, 00, 00, 00, 00, 00
};

static bool8	FlashMode;
static uint32	FlashSize;
static uint8	*MapROM, *FlashROM;

static void BSX_Map_SNES (void);
static void BSX_Map_LoROM (void);
static void BSX_Map_HiROM (void);
static void BSX_Map_MMC (void);
static void BSX_Map_FlashIO (void);
static void BSX_Map_SRAM (void);
static void BSX_Map_PSRAM (void);
static void BSX_Map_BIOS (void);
static void BSX_Map_RAM (void);
static void BSX_Map (void);
static bool8 BSX_LoadBIOS (void);
static void map_psram_mirror_sub (uint32);
static int is_bsx (unsigned char *);


static void BSX_Map_SNES (void)
{
	// These maps will be partially overwritten

	int	c;

	// Banks 00->3F and 80->BF
	for (c = 0; c < 0x400; c += 16)
	{
		Map[c + 0] = Map[c + 0x800] = RAM;
		Map[c + 1] = Map[c + 0x801] = RAM;
		BlockIsRAM[c + 0] = BlockIsRAM[c + 0x800] = TRUE;
		BlockIsRAM[c + 1] = BlockIsRAM[c + 0x801] = TRUE;

		Map[c + 2] = Map[c + 0x802] = (uint8 *) MAP_PPU;
		Map[c + 3] = Map[c + 0x803] = (uint8 *) MAP_PPU;
		Map[c + 4] = Map[c + 0x804] = (uint8 *) MAP_CPU;
		Map[c + 5] = Map[c + 0x805] = (uint8 *) MAP_CPU;
		Map[c + 6] = Map[c + 0x806] = (uint8 *) MAP_NONE;
		Map[c + 7] = Map[c + 0x807] = (uint8 *) MAP_NONE;
	}
}

static void BSX_Map_LoROM (void)
{
	// These maps will be partially overwritten

	int	i, c;

	// Banks 00->3F and 80->BF
	for (c = 0; c < 0x400; c += 16)
	{
		for (i = c + 8; i < c + 16; i++)
		{
			Map[i] = Map[i + 0x800] = &MapROM[(c << 11) % FlashSize] - 0x8000;
			BlockIsRAM[i] = BlockIsRAM[i + 0x800] = BSX.write_enable;
			BlockIsROM[i] = BlockIsROM[i + 0x800] = !BSX.write_enable;
		}
	}

	// Banks 40->7F and C0->FF
	for (c = 0; c < 0x400; c += 16)
	{
		for (i = c; i < c + 8; i++)
			Map[i + 0x400] = Map[i + 0xC00] = &MapROM[(c << 11) % FlashSize];

		for (i = c + 8; i < c + 16; i++)
			Map[i + 0x400] = Map[i + 0xC00] = &MapROM[(c << 11) % FlashSize] - 0x8000;

		for (i = c; i < c + 16; i++)
		{
			BlockIsRAM[i + 0x400] = BlockIsRAM[i + 0xC00] = BSX.write_enable;
			BlockIsROM[i + 0x400] = BlockIsROM[i + 0xC00] = !BSX.write_enable;
		}
	}
}

static void BSX_Map_HiROM (void)
{
	// These maps will be partially overwritten

	int	i, c;

	// Banks 00->3F and 80->BF
	for (c = 0; c < 0x400; c += 16)
	{
		for (i = c + 8; i < c + 16; i++)
		{
			Map[i] = Map[i + 0x800] = &MapROM[(c << 12) % FlashSize];
			BlockIsRAM[i] = BlockIsRAM[i + 0x800] = BSX.write_enable;
			BlockIsROM[i] = BlockIsROM[i + 0x800] = !BSX.write_enable;
		}
	}

	// Banks 40->7F and C0->FF
	for (c = 0; c < 0x400; c += 16)
	{
		for (i = c; i < c + 16; i++)
		{
			Map[i + 0x400] = Map[i + 0xC00] = &MapROM[(c << 12) % FlashSize];
			BlockIsRAM[i + 0x400] = BlockIsRAM[i + 0xC00] = BSX.write_enable;
			BlockIsROM[i + 0x400] = BlockIsROM[i + 0xC00] = !BSX.write_enable;
		}
	}
}

static void BSX_Map_MMC (void)
{
	int	c;

	// Banks 01->0E:5000-5FFF
	for (c = 0x010; c < 0x0F0; c += 16)
	{
		Map[c + 5] = (uint8 *) MAP_BSX;
		BlockIsRAM[c + 5] = BlockIsROM[c + 5] = FALSE;
	}
}

static void BSX_Map_FlashIO (void)
{
	int	i, c;

	if (BSX.prevMMC[0x0C])
	{
		// Banks 00->3F and 80->BF
		for (c = 0; c < 0x400; c += 16)
		{
			for (i = c + 8; i < c + 16; i++)
			{
				Map[i] = Map[i + 0x800] = (uint8 *)MAP_BSX;
				BlockIsRAM[i] = BlockIsRAM[i + 0x800] = TRUE;
				BlockIsROM[i] = BlockIsROM[i + 0x800] = FALSE;
			}
		}

		// Banks 40->7F and C0->FF
		for (c = 0; c < 0x400; c += 16)
		{
			for (i = c; i < c + 16; i++)
			{
				Map[i + 0x400] = Map[i + 0xC00] = (uint8 *)MAP_BSX;
				BlockIsRAM[i + 0x400] = BlockIsRAM[i + 0xC00] = TRUE;
				BlockIsROM[i + 0x400] = BlockIsROM[i + 0xC00] = FALSE;
			}
		}
	}	
}

static void BSX_Map_SRAM (void)
{
	int	c;

	// Banks 10->17:5000-5FFF
	for (c = 0x100; c < 0x180; c += 16)
	{
		Map[c + 5] = (uint8 *) SRAM + ((c & 0x70) << 8) - 0x5000;
		BlockIsRAM[c + 5] = TRUE;
		BlockIsROM[c + 5] = FALSE;
	}
}

static void map_psram_mirror_sub (uint32 bank)
{
	int	i, c;

	bank <<= 4;

	if (BSX.prevMMC[0x02])
	{
		//HiROM
		for (c = 0; c < 0x80; c += 16)
		{
			if ((bank & 0x7F0) >= 0x400)
			{
				for (i = c; i < c + 16; i++)
				{
					Map[i + bank] = &PSRAM[(c << 12) % PSRAM_SIZE];
					BlockIsRAM[i + bank] = TRUE;
					BlockIsROM[i + bank] = FALSE;
				}
			}
			else
			{
				for (i = c + 8; i < c + 16; i++)
				{
					Map[i + bank] = &PSRAM[(c << 12) % PSRAM_SIZE];
					BlockIsRAM[i + bank] = TRUE;
					BlockIsROM[i + bank] = FALSE;
				}
			}
		}
	}
	else
	{
		//LoROM
		for (c = 0; c < 0x100; c += 16)
		{
			if ((bank & 0x7F0) >= 0x400)
			{
				for (i = c; i < c + 8; i++)
				{
					Map[i + bank] = &PSRAM[(c << 11) % PSRAM_SIZE];
					BlockIsRAM[i + bank] = TRUE;
					BlockIsROM[i + bank] = FALSE;
				}
			}

			for (i = c + 8; i < c + 16; i++)
			{
				Map[i + bank] = &PSRAM[(c << 11) % PSRAM_SIZE] - 0x8000;
				BlockIsRAM[i + bank] = TRUE;
				BlockIsROM[i + bank] = FALSE;
			}
		}
	}
}

static void BSX_Map_PSRAM(void)
{
	int	c;

	if (!BSX.prevMMC[0x02])
	{
		//LoROM Mode
		if (!BSX.prevMMC[0x05] && !BSX.prevMMC[0x06])
		{
			//Map PSRAM to 00-0F/80-8F
			if (BSX.prevMMC[0x03])
				map_psram_mirror_sub(0x00);

			if (BSX.prevMMC[0x04])
				map_psram_mirror_sub(0x80);
		}
		else if (BSX.prevMMC[0x05] && !BSX.prevMMC[0x06])
		{
			//Map PSRAM to 20-2F/A0-AF
			if (BSX.prevMMC[0x03])
				map_psram_mirror_sub(0x20);

			if (BSX.prevMMC[0x04])
				map_psram_mirror_sub(0xA0);
		}
		else if (!BSX.prevMMC[0x05] && BSX.prevMMC[0x06])
		{
			//Map PSRAM to 40-4F/C0-CF
			if (BSX.prevMMC[0x03])
				map_psram_mirror_sub(0x40);

			if (BSX.prevMMC[0x04])
				map_psram_mirror_sub(0xC0);
		}
		else
		{
			//Map PSRAM to 60-6F/E0-EF
			if (BSX.prevMMC[0x03])
				map_psram_mirror_sub(0x60);

			if (BSX.prevMMC[0x04])
				map_psram_mirror_sub(0xE0);
		}

		//Map PSRAM to 70-7D/F0-FF
		if (BSX.prevMMC[0x03])
			map_psram_mirror_sub(0x70);

		if (BSX.prevMMC[0x04])
			map_psram_mirror_sub(0xF0);
	}
	else
	{
		//HiROM Mode
		if (!BSX.prevMMC[0x05] && !BSX.prevMMC[0x06])
		{
			//Map PSRAM to 00-07/40-47 / 80-87/C0-C7
			if (BSX.prevMMC[0x03])
			{
				map_psram_mirror_sub(0x00);
				map_psram_mirror_sub(0x40);
			}

			if (BSX.prevMMC[0x04])
			{
				map_psram_mirror_sub(0x80);
				map_psram_mirror_sub(0xC0);
			}
		}
		else if (BSX.prevMMC[0x05] && !BSX.prevMMC[0x06])
		{
			//Map PSRAM to 10-17/50-57 / 90-97-D0-D7
			if (BSX.prevMMC[0x03])
			{
				map_psram_mirror_sub(0x10);
				map_psram_mirror_sub(0x50);
			}

			if (BSX.prevMMC[0x04])
			{
				map_psram_mirror_sub(0x90);
				map_psram_mirror_sub(0xD0);
			}
		}
		else if (!BSX.prevMMC[0x05] && BSX.prevMMC[0x06])
		{
			//Map PSRAM to 20-27/60-67 / A0-A7/E0-E7
			if (BSX.prevMMC[0x03])
			{
				map_psram_mirror_sub(0x20);
				map_psram_mirror_sub(0x60);
			}

			if (BSX.prevMMC[0x04])
			{
				map_psram_mirror_sub(0xA0);
				map_psram_mirror_sub(0xE0);
			}
		}
		else
		{
			//Map PSRAM to 30-37/70-77 / B0-B7/F0-F7
			if (BSX.prevMMC[0x03])
			{
				map_psram_mirror_sub(0x30);
				map_psram_mirror_sub(0x70);
			}

			if (BSX.prevMMC[0x04])
			{
				map_psram_mirror_sub(0xB0);
				map_psram_mirror_sub(0xF0);
			}
		}

		if (BSX.prevMMC[0x03])
		{
			//Map PSRAM to 20->3F:6000-7FFF
			for (c = 0x200; c < 0x400; c += 16)
			{
				Map[c + 6] = &PSRAM[((c & 0x70) << 12) % PSRAM_SIZE];
				Map[c + 7] = &PSRAM[((c & 0x70) << 12) % PSRAM_SIZE];
				BlockIsRAM[c + 6] = TRUE;
				BlockIsRAM[c + 7] = TRUE;
				BlockIsROM[c + 6] = FALSE;
				BlockIsROM[c + 7] = FALSE;
			}
		}

		if (BSX.prevMMC[0x04])
		{
			//Map PSRAM to A0->BF:6000-7FFF
			for (c = 0xA00; c < 0xC00; c += 16)
			{
				Map[c + 6] = &PSRAM[((c & 0x70) << 12) % PSRAM_SIZE];
				Map[c + 7] = &PSRAM[((c & 0x70) << 12) % PSRAM_SIZE];
				BlockIsRAM[c + 6] = TRUE;
				BlockIsRAM[c + 7] = TRUE;
				BlockIsROM[c + 6] = FALSE;
				BlockIsROM[c + 7] = FALSE;
			}
		}
	}
}

static void BSX_Map_BIOS (void)
{
	int	i,c;

	// Banks 00->1F:8000-FFFF
	if (BSX.prevMMC[0x07])
	{
		for (c = 0; c < 0x200; c += 16)
		{
			for (i = c + 8; i < c + 16; i++)
			{
				Map[i] = &BIOSROM[(c << 11) % BIOS_SIZE] - 0x8000;
				BlockIsRAM[i] = FALSE;
				BlockIsROM[i] = TRUE;
			}
		}
	}

	// Banks 80->9F:8000-FFFF
	if (BSX.prevMMC[0x08])
	{
		for (c = 0; c < 0x200; c += 16)
		{
			for (i = c + 8; i < c + 16; i++)
			{
				Map[i + 0x800] = &BIOSROM[(c << 11) % BIOS_SIZE] - 0x8000;
				BlockIsRAM[i + 0x800] = FALSE;
				BlockIsROM[i + 0x800] = TRUE;
			}
		}
	}
}

static void BSX_Map_RAM (void)
{
	int	c;

	// Banks 7E->7F
	for (c = 0; c < 16; c++)
	{
		Map[c + 0x7E0] = RAM;
		Map[c + 0x7F0] = RAM + 0x10000;
		BlockIsRAM[c + 0x7E0] = TRUE;
		BlockIsRAM[c + 0x7F0] = TRUE;
		BlockIsROM[c + 0x7E0] = FALSE;
		BlockIsROM[c + 0x7F0] = FALSE;
	}
}

static void BSX_Map (void)
{
#ifdef BSX_DEBUG
	printf("BS: Remapping\n");
	for (int i = 0; i < 32; i++)
		printf("BS: MMC %02X: %d\n", i, BSX.MMC[i]);
#endif

	memcpy(BSX.prevMMC, BSX.MMC, sizeof(BSX.MMC));

	MapROM = FlashROM;
	FlashSize = FLASH_SIZE;
	
	if (BSX.prevMMC[0x02])
		BSX_Map_HiROM();
	else
		BSX_Map_LoROM();
	
	BSX_Map_FlashIO();
	BSX_Map_PSRAM();

	BSX_Map_SNES();
	BSX_Map_SRAM();
	BSX_Map_RAM();

	BSX_Map_BIOS();
	BSX_Map_MMC();

	// Monitor new register changes
	BSX.dirty  = FALSE;
	BSX.dirty2 = FALSE;

	Memory.map_WriteProtectROM();
}

static uint8 BSX_Get_Bypass_FlashIO (uint32 offset)
{
	//For games other than BS-X
	FlashROM = Memory.ROM + Multi.cartOffsetB;

	if (BSX.prevMMC[0x02])
		return (FlashROM[offset & 0x0FFFFF]);
	else
		return (FlashROM[(offset & 0x1F0000) >> 1 | (offset & 0x7FFF)]);
}

static void BSX_Set_Bypass_FlashIO (uint32 offset, uint8 byte)
{
	//For games other than BS-X
	FlashROM = Memory.ROM + Multi.cartOffsetB;

	if (BSX.prevMMC[0x02])
		FlashROM[offset & 0x0FFFFF] = FlashROM[offset & 0x0FFFFF] & byte;
	else
		FlashROM[(offset & 0x1F0000) >> 1 | (offset & 0x7FFF)] = FlashROM[(offset & 0x1F0000) >> 1 | (offset & 0x7FFF)] & byte;
}

uint8 S9xGetBSX (uint32 address)
{
	uint8	bank = (address >> 16) & 0xFF;
	uint16	offset = address & 0xFFFF;
	uint8	t = 0;

	// MMC
	if ((bank >= 0x01 && bank <= 0x0E) && ((address & 0xF000) == 0x5000))
		return (BSX.MMC[bank]);

	// Flash Mapping

	// default: read-through mode
	t = BSX_Get_Bypass_FlashIO(address);

	// note: may be more registers, purposes unknown
	switch (offset)
	{
		case 0x0002:
		case 0x8002:
			if (BSX.flash_bsr)
				t = 0xC0; // Page Status Register
			break;

		case 0x0004:
		case 0x8004:
			if (BSX.flash_gsr)
				t = 0x82; // Global Status Register
			break;

		case 0x5555:
			if (BSX.flash_enable)
				t = 0x80; // ???
			break;

		case 0xFF00:
		case 0xFF02:
		case 0xFF04:
		case 0xFF06:
		case 0xFF08:
		case 0xFF0A:
		case 0xFF0C:
		case 0xFF0E:
		case 0xFF10:
		case 0xFF12:
			// return flash vendor information
			if (BSX.read_enable)
				t = flashcard[offset - 0xFF00];
			break;
	}

	if (BSX.flash_csr)
	{
		t = 0x80; // Compatible Status Register
		BSX.flash_csr = false;
	}

	return (t);
}

void S9xSetBSX (uint8 byte, uint32 address)
{
	uint8	bank = (address >> 16) & 0xFF;

	// MMC
	if ((bank >= 0x01 && bank <= 0x0E) && ((address & 0xF000) == 0x5000))
	{
		//Avoid updating the memory map when it is not needed
		if (bank == 0x0E && BSX.dirty)
		{
			BSX_Map();
			BSX.dirty = FALSE;
		}
		else if (bank != 0x0E && BSX.MMC[bank] != byte)
		{
			BSX.dirty = TRUE;
		}

		BSX.MMC[bank] = byte;
	}

	// Flash IO
	
	// Write to Flash
	if (BSX.write_enable)
	{
		BSX_Set_Bypass_FlashIO(address, byte);
		BSX.write_enable = false;
		return;
	}

	// Flash Command Handling
	
	//Memory Pack Type 1 & 3 & 4
	BSX.flash_command <<= 8;
	BSX.flash_command |= byte;

	switch (BSX.flash_command & 0xFF)
	{
		case 0x00:
		case 0xFF:
			//Reset to normal
			BSX.flash_enable = false;
			BSX.flash_bsr = false;
			BSX.flash_csr = false;
			BSX.flash_gsr = false;
			BSX.read_enable = false;
			BSX.write_enable = false;
			BSX.flash_cmd_done = true;
			break;

		case 0x10:
		case 0x40:
			//Write Byte
			BSX.flash_enable = false;
			BSX.flash_bsr = false;
			BSX.flash_csr = true;
			BSX.flash_gsr = false;
			BSX.read_enable = false;
			BSX.write_enable = true;
			BSX.flash_cmd_done = true;
			break;

		case 0x50:
			//Clear Status Register
			BSX.flash_enable = false;
			BSX.flash_bsr = false;
			BSX.flash_csr = false;
			BSX.flash_gsr = false;
			BSX.flash_cmd_done = true;
			break;

		case 0x70:
			//Read CSR
			BSX.flash_enable = false;
			BSX.flash_bsr = false;
			BSX.flash_csr = true;
			BSX.flash_gsr = false;
			BSX.read_enable = false;
			BSX.write_enable = false;
			BSX.flash_cmd_done = true;
			break;

		case 0x71:
			//Read Extended Status Registers (Page and Global)
			BSX.flash_enable = false;
			BSX.flash_bsr = true;
			BSX.flash_csr = false;
			BSX.flash_gsr = true;
			BSX.read_enable = false;
			BSX.write_enable = false;
			BSX.flash_cmd_done = true;
			break;

		case 0x75:
			//Show Page Buffer / Vendor Info
			BSX.flash_csr = false;
			BSX.read_enable = true;
			BSX.flash_cmd_done = true;
			break;

		case 0xD0:
			//DO COMMAND
			switch (BSX.flash_command & 0xFFFF)
			{
				case 0x20D0: //Block Erase
					uint32 x;
					for (x = 0; x < 0x10000; x++) {
						//BSX_Set_Bypass_FlashIO(((address & 0xFF0000) + x), 0xFF);
						if (BSX.MMC[0x02])
							FlashROM[(address & 0x0F0000) + x] = 0xFF;
						else
							FlashROM[((address & 0x1E0000) >> 1) + x] = 0xFF;
					}
					break;

				case 0xA7D0: //Chip Erase (ONLY IN TYPE 1 AND 4)
					if ((flashcard[6] & 0xF0) == 0x10 || (flashcard[6] & 0xF0) == 0x40)
					{
						uint32 x;
						for (x = 0; x < FLASH_SIZE; x++) {
							//BSX_Set_Bypass_FlashIO(x, 0xFF);
							FlashROM[x] = 0xFF;
						}
					}
					break;

				case 0x38D0: //Flashcart Reset
					break;
			}
			break;
	}
}

void S9xBSXSetStream1 (uint8 count)
{
	if (BSX.sat_stream1.is_open())
		BSX.sat_stream1.close(); //If Stream already opened for one file: Close it.

	char path[PATH_MAX + 1], name[PATH_MAX + 1];

	strcpy(path, S9xGetDirectory(SAT_DIR));
	strcat(path, SLASH_STR);

	snprintf(name, PATH_MAX + 1, "BSX%04X-%d.bin", (BSX.PPU[0x2188 - BSXPPUBASE] | (BSX.PPU[0x2189 - BSXPPUBASE] * 256)), count); //BSXHHHH-DDD.bin
	strcat(path, name);

	BSX.sat_stream1.clear();
	BSX.sat_stream1.open(path, std::ios::in | std::ios::binary);
	if (BSX.sat_stream1.good())
	{
		BSX.sat_stream1.seekg(0, BSX.sat_stream1.end);
		long str1size = BSX.sat_stream1.tellg();
		BSX.sat_stream1.seekg(0, BSX.sat_stream1.beg);
		float QueueSize = str1size / 22.;
		BSX.sat_stream1_queue = (uint16)(ceil(QueueSize));
		BSX.PPU[0x218D - BSXPPUBASE] = 0;
		BSX.sat_stream1_first = TRUE;
		BSX.sat_stream1_loaded = TRUE;
	}
	else
	{
		BSX.sat_stream1_loaded = FALSE;
	}
}

void S9xBSXSetStream2 (uint8 count)
{
	if (BSX.sat_stream2.is_open())
		BSX.sat_stream2.close(); //If Stream already opened for one file: Close it.

	char path[PATH_MAX + 1], name[PATH_MAX + 1];

	strcpy(path, S9xGetDirectory(SAT_DIR));
	strcat(path, SLASH_STR);

	snprintf(name, PATH_MAX + 1, "BSX%04X-%d.bin", (BSX.PPU[0x218E - BSXPPUBASE] | (BSX.PPU[0x218F - BSXPPUBASE] * 256)), count); //BSXHHHH-DDD.bin
	strcat(path, name);

	BSX.sat_stream2.clear();
	BSX.sat_stream2.open(path, std::ios::in | std::ios::binary);
	if (BSX.sat_stream2.good())
	{
		BSX.sat_stream2.seekg(0, BSX.sat_stream2.end);
		long str2size = BSX.sat_stream2.tellg();
		BSX.sat_stream2.seekg(0, BSX.sat_stream2.beg);
		float QueueSize = str2size / 22.;
		BSX.sat_stream2_queue = (uint16)(ceil(QueueSize));
		BSX.PPU[0x2193 - BSXPPUBASE] = 0;
		BSX.sat_stream2_first = TRUE;
		BSX.sat_stream2_loaded = TRUE;
	}
	else
	{
		BSX.sat_stream2_loaded = FALSE;
	}
}

uint8 S9xBSXGetRTC (void)
{
	//Get Time
	time_t		t;
	struct tm	*tmr;

	time(&t);
	tmr = localtime(&t);

	BSX.test2192[0] = 0x00;
	BSX.test2192[1] = 0x00;
	BSX.test2192[2] = 0x00;
	BSX.test2192[3] = 0x00;
	BSX.test2192[4] = 0x10;
	BSX.test2192[5] = 0x01;
	BSX.test2192[6] = 0x01;
	BSX.test2192[7] = 0x00;
	BSX.test2192[8] = 0x00;
	BSX.test2192[9] = 0x00;
	BSX.test2192[10] = BSX_RTC.seconds = tmr->tm_sec;
	BSX.test2192[11] = BSX_RTC.minutes = tmr->tm_min;
	BSX.test2192[12] = BSX_RTC.hours = tmr->tm_hour;
	BSX.test2192[13] = BSX_RTC.dayweek = (tmr->tm_wday) + 1;
	BSX.test2192[14] = BSX_RTC.day = tmr->tm_mday;
	BSX.test2192[15] = BSX_RTC.month = (tmr->tm_mon) + 1;
	BSX_RTC.year = tmr->tm_year + 1900;
	BSX.test2192[16] = (BSX_RTC.year) & 0xFF;
	BSX.test2192[17] = (BSX_RTC.year) >> 8;

	t = BSX.test2192[BSX.out_index++];

	if (BSX.out_index > 22)
		BSX.out_index = 0;

	return t;
}

uint8 S9xGetBSXPPU (uint16 address)
{
	uint8	t;

	// known read registers
	switch (address)
	{
		//Stream 1
		// Logical Channel 1 + Data Structure (R/W)
		case 0x2188:
			t = BSX.PPU[0x2188 - BSXPPUBASE];
			break;

		// Logical Channel 2 (R/W) [6bit]
		case 0x2189:
			t = BSX.PPU[0x2189 - BSXPPUBASE];
			break;

		// Prefix Count (R)
		case 0x218A:
			if (!BSX.sat_pf_latch1_enable || !BSX.sat_dt_latch1_enable)
			{
				t = 0;
				break;
			}

			if (BSX.PPU[0x2188 - BSXPPUBASE] == 0 && BSX.PPU[0x2189 - BSXPPUBASE] == 0)
			{
				t = 1;
				break;
			}

			if (BSX.sat_stream1_queue <= 0)
			{
				BSX.sat_stream1_count++;
				S9xBSXSetStream1(BSX.sat_stream1_count - 1);
			}

			if (!BSX.sat_stream1_loaded && (BSX.sat_stream1_count - 1) > 0)
			{
				BSX.sat_stream1_count = 1;
				S9xBSXSetStream1(BSX.sat_stream1_count - 1);
			}

			if (BSX.sat_stream1_loaded)
			{
				//Lock at 0x7F for bigger packets
				if (BSX.sat_stream1_queue >= 128)
					BSX.PPU[0x218A - BSXPPUBASE] = 0x7F;
				else
					BSX.PPU[0x218A - BSXPPUBASE] = BSX.sat_stream1_queue;
				t = BSX.PPU[0x218A - BSXPPUBASE];
			}
			else
				t = 0;
			break;

		// Prefix Latch (R/W)
		case 0x218B:
			if (BSX.sat_pf_latch1_enable)
			{
				if (BSX.PPU[0x2188 - BSXPPUBASE] == 0 && BSX.PPU[0x2189 - BSXPPUBASE] == 0)
				{
					BSX.PPU[0x218B - BSXPPUBASE] = 0x90;
				}

				if (BSX.sat_stream1_loaded)
				{
					uint8 temp = 0;
					if (BSX.sat_stream1_first)
					{
						// First packet
						temp |= 0x10;
						BSX.sat_stream1_first = FALSE;
					}

					BSX.sat_stream1_queue--;

					if (BSX.sat_stream1_queue == 0)
					{
						//Last packet
						temp |= 0x80;
					}

					BSX.PPU[0x218B - BSXPPUBASE] = temp;
				}

				BSX.PPU[0x218D - BSXPPUBASE] |= BSX.PPU[0x218B - BSXPPUBASE];
				t = BSX.PPU[0x218B - BSXPPUBASE];
			}
			else
			{
				t = 0;
			}
			break;

		// Data Latch (R/W)
		case 0x218C:
			if (BSX.sat_dt_latch1_enable)
			{
				if (BSX.PPU[0x2188 - BSXPPUBASE] == 0 && BSX.PPU[0x2189 - BSXPPUBASE] == 0)
				{
					BSX.PPU[0x218C - BSXPPUBASE] = S9xBSXGetRTC();
				}
				else if (BSX.sat_stream1_loaded)
				{
					if (BSX.sat_stream1.eof())
						BSX.PPU[0x218C - BSXPPUBASE] = 0xFF;
					else
						BSX.PPU[0x218C - BSXPPUBASE] = BSX.sat_stream1.get();
				}
				t = BSX.PPU[0x218C - BSXPPUBASE];
			}
			else
			{
				t = 0;
			}
			break;

		// OR gate (R)
		case 0x218D:
			t = BSX.PPU[0x218D - BSXPPUBASE];
			BSX.PPU[0x218D - BSXPPUBASE] = 0;
			break;

		//Stream 2
		// Logical Channel 1 + Data Structure (R/W)
		case 0x218E:
			t = BSX.PPU[0x218E - BSXPPUBASE];
			break;

		// Logical Channel 2 (R/W) [6bit]
		case 0x218F:
			t = BSX.PPU[0x218F - BSXPPUBASE];
			break;

		// Prefix Count (R)
		case 0x2190:
			if (!BSX.sat_pf_latch2_enable || !BSX.sat_dt_latch2_enable)
			{
				t = 0;
				break;
			}

			if (BSX.PPU[0x218E - BSXPPUBASE] == 0 && BSX.PPU[0x218F - BSXPPUBASE] == 0)
			{
				t = 1;
				break;
			}

			if (BSX.sat_stream2_queue <= 0)
			{
				BSX.sat_stream2_count++;
				S9xBSXSetStream2(BSX.sat_stream2_count - 1);
			}

			if (!BSX.sat_stream2_loaded && (BSX.sat_stream2_count - 1) > 0)
			{
				BSX.sat_stream2_count = 1;
				S9xBSXSetStream2(BSX.sat_stream2_count - 1);
			}

			if (BSX.sat_stream2_loaded)
			{
				if (BSX.sat_stream2_queue >= 128)
					BSX.PPU[0x2190 - BSXPPUBASE] = 0x7F;
				else
					BSX.PPU[0x2190 - BSXPPUBASE] = BSX.sat_stream2_queue;
				t = BSX.PPU[0x2190 - BSXPPUBASE];
			}
			else
				t = 0;
			break;

		// Prefix Latch (R/W)
		case 0x2191:
			if (BSX.sat_pf_latch2_enable)
			{
				if (BSX.PPU[0x218E - BSXPPUBASE] == 0 && BSX.PPU[0x218F - BSXPPUBASE] == 0)
				{
					BSX.PPU[0x2191 - BSXPPUBASE] = 0x90;
				}

				if (BSX.sat_stream2_loaded)
				{
					uint8 temp = 0;
					if (BSX.sat_stream2_first)
					{
						// First packet
						temp |= 0x10;
						BSX.sat_stream2_first = FALSE;
					}

					BSX.sat_stream2_queue--;

					if (BSX.sat_stream2_queue == 0)
					{
						//Last packet
						temp |= 0x80;
					}

					BSX.PPU[0x2191 - BSXPPUBASE] = temp;
				}

				BSX.PPU[0x2193 - BSXPPUBASE] |= BSX.PPU[0x2191 - BSXPPUBASE];
				t = BSX.PPU[0x2191 - BSXPPUBASE];
			}
			else
			{
				t = 0;
			}
			break;

		// Data Latch (R/W)
		case 0x2192:
			if (BSX.sat_dt_latch2_enable)
			{
				if (BSX.PPU[0x218E - BSXPPUBASE] == 0 && BSX.PPU[0x218F - BSXPPUBASE] == 0)
				{
					BSX.PPU[0x2192 - BSXPPUBASE] = S9xBSXGetRTC();
				}
				else if (BSX.sat_stream2_loaded)
				{
					if (BSX.sat_stream2.eof())
						BSX.PPU[0x2192 - BSXPPUBASE] = 0xFF;
					else
						BSX.PPU[0x2192 - BSXPPUBASE] = BSX.sat_stream2.get();
				}
				t = BSX.PPU[0x2192 - BSXPPUBASE];
			}
			else
			{
				t = 0;
			}
			break;

		// OR gate (R)
		case 0x2193:
			t = BSX.PPU[0x2193 - BSXPPUBASE];
			BSX.PPU[0x2193 - BSXPPUBASE] = 0;
			break;

		//Other
		// Satellaview LED / Stream Enable (R/W) [4bit]
		case 0x2194:
			t = BSX.PPU[0x2194 - BSXPPUBASE];
			break;

		// Unknown
		case 0x2195:
			t = BSX.PPU[0x2195 - BSXPPUBASE];
			break;

		// Satellaview Status (R)
		case 0x2196:
			t = BSX.PPU[0x2196 - BSXPPUBASE];
			break;

		// Soundlink Settings (R/W)
		case 0x2197:
			t = BSX.PPU[0x2197 - BSXPPUBASE];
			break;

		// Serial I/O - Serial Number (R/W)
		case 0x2198:
			t = BSX.PPU[0x2198 - BSXPPUBASE];
			break;

		// Serial I/O - Unknown (R/W)
		case 0x2199:
			t = BSX.PPU[0x2199 - BSXPPUBASE];
			break;

		default:
			t = OpenBus;
			break;
	}

	return (t);
}

void S9xSetBSXPPU (uint8 byte, uint16 address)
{
	// known write registers
	switch (address)
	{
		//Stream 1
		// Logical Channel 1 + Data Structure (R/W)
		case 0x2188:
			if (BSX.PPU[0x2188 - BSXPPUBASE] == byte)
			{
				BSX.sat_stream1_count = 0;
			}
			BSX.PPU[0x2188 - BSXPPUBASE] = byte;
			break;

		// Logical Channel 2 (R/W) [6bit]
		case 0x2189:
			if (BSX.PPU[0x2188 - BSXPPUBASE] == (byte & 0x3F))
			{
				BSX.sat_stream1_count = 0;
			}
			BSX.PPU[0x2189 - BSXPPUBASE] = byte & 0x3F;
			break;

		// Prefix Latch (R/W)
		case 0x218B:
			BSX.sat_pf_latch1_enable = (byte != 0);
			break;

		// Data Latch (R/W)
		case 0x218C:
			if (BSX.PPU[0x2188 - BSXPPUBASE] == 0 && BSX.PPU[0x2189 - BSXPPUBASE] == 0)
			{
				BSX.out_index = 0;
			}
			BSX.sat_dt_latch1_enable = (byte != 0);
			break;

		//Stream 2
		// Logical Channel 1 + Data Structure (R/W)
		case 0x218E:
			if (BSX.PPU[0x218E - BSXPPUBASE] == byte)
			{
				BSX.sat_stream2_count = 0;
			}
			BSX.PPU[0x218E - BSXPPUBASE] = byte;
			break;

		// Logical Channel 2 (R/W) [6bit]
		case 0x218F:
			if (BSX.PPU[0x218F - BSXPPUBASE] == (byte & 0x3F))
			{
				BSX.sat_stream2_count = 0;
			}
			BSX.PPU[0x218F - BSXPPUBASE] = byte & 0x3F;
			break;

		// Prefix Latch (R/W)
		case 0x2191:
			BSX.sat_pf_latch2_enable = (byte != 0);
			break;

		// Data Latch (R/W)
		case 0x2192:
			if (BSX.PPU[0x218E - BSXPPUBASE] == 0 && BSX.PPU[0x218F - BSXPPUBASE] == 0)
			{
				BSX.out_index = 0;
			}
			BSX.sat_dt_latch2_enable = (byte != 0);
			break;

		//Other
		// Satellaview LED / Stream Enable (R/W) [4bit]
		case 0x2194:
			BSX.PPU[0x2194 - BSXPPUBASE] = byte & 0x0F;
			break;

		// Soundlink Settings (R/W)
		case 0x2197:
			BSX.PPU[0x2197 - BSXPPUBASE] = byte;
			break;
	}
}

uint8 * S9xGetBasePointerBSX (uint32 address)
{
	return (MapROM);
}

static bool8 BSX_LoadBIOS (void)
{
	FILE	*fp;
	char	path[PATH_MAX + 1], name[PATH_MAX + 1];
	bool8	r = FALSE;

	strcpy(path, S9xGetDirectory(BIOS_DIR));
	strcat(path, SLASH_STR);
	strcpy(name, path);
	strcat(name, "BS-X.bin");

	fp = fopen(name, "rb");
	if (!fp)
	{
		strcpy(name, path);
		strcat(name, "BS-X.bios");
		fp = fopen(name, "rb");
	}

	if (fp)
	{
		size_t	size;

		size = fread((void *) BIOSROM, 1, BIOS_SIZE, fp);
		fclose(fp);
		if (size == BIOS_SIZE)
			r = TRUE;
	}

#ifdef BSX_DEBUG
	if (r)
		printf("BS: BIOS found.\n");
	else
		printf("BS: BIOS not found!\n");
#endif

	return (r);
}

static bool8 is_BSX_BIOS (const uint8 *data, uint32 size)
{
	if (size == BIOS_SIZE && strncmp((char *) (data + 0x7FC0), "Satellaview BS-X     ", 21) == 0)
		return (TRUE);
	else
		return (FALSE);
}

void S9xInitBSX (void)
{
	Settings.BS = FALSE;

    if (is_BSX_BIOS(Memory.ROM,Memory.CalculatedSize))
	{
		// BS-X itself

		Settings.BS = TRUE;
		Settings.BSXItself = TRUE;

		Memory.LoROM = TRUE;
		Memory.HiROM = FALSE;

		memmove(BIOSROM, Memory.ROM, BIOS_SIZE);

		FlashMode = FALSE;
		FlashSize = FLASH_SIZE;

		BSX.bootup = TRUE;
	}
	else
	{
		Settings.BSXItself = FALSE;

		int	r1, r2;

		r1 = (is_bsx(Memory.ROM + 0x7FC0) == 1);
		r2 = (is_bsx(Memory.ROM + 0xFFC0) == 1);
		Settings.BS = (r1 | r2) ? TRUE : FALSE;

		if (Settings.BS)
		{
			// BS games

			Memory.LoROM = r1 ? TRUE : FALSE;
			Memory.HiROM = r2 ? TRUE : FALSE;

			uint8	*header = r1 ? Memory.ROM + 0x7FC0 : Memory.ROM + 0xFFC0;

			FlashMode = (header[0x18] & 0xEF) == 0x20 ? FALSE : TRUE;
			FlashSize = FLASH_SIZE;

#ifdef BSX_DEBUG
			for (int i = 0; i <= 0x1F; i++)
				printf("BS: ROM Header %02X: %02X\n", i, header[i]);
			printf("BS: FlashMode: %d, FlashSize: %x\n", FlashMode, FlashSize);
#endif

			BSX.bootup = Settings.BSXBootup;

			if (!BSX_LoadBIOS() && !is_BSX_BIOS(BIOSROM,BIOS_SIZE))
			{
				BSX.bootup = FALSE;
				memset(BIOSROM, 0, BIOS_SIZE);
			}
		}
	}

	if (Settings.BS)
	{
		MapROM = NULL;
		FlashROM = Memory.ROM;
		/*
		time_t		t;
		struct tm	*tmr;

		time(&t);
		tmr = localtime(&t);

		BSX_RTC.ticks = 0;
		memcpy(BSX.test2192, init2192, sizeof(init2192));
		BSX.test2192[10] = BSX_RTC.seconds = tmr->tm_sec;
		BSX.test2192[11] = BSX_RTC.minutes = tmr->tm_min;
		BSX.test2192[12] = BSX_RTC.hours   = tmr->tm_hour;
#ifdef BSX_DEBUG
		printf("BS: Current Time: %02d:%02d:%02d\n",  BSX_RTC.hours, BSX_RTC.minutes, BSX_RTC.seconds);
#endif
		*/
		SNESGameFixes.SRAMInitialValue = 0x00;
	}
}

void S9xResetBSX (void)
{
	if (Settings.BSXItself)
		memset(Memory.ROM, 0, FLASH_SIZE);

	memset(BSX.PPU, 0, sizeof(BSX.PPU));
	memset(BSX.MMC, 0, sizeof(BSX.MMC));
	memset(BSX.prevMMC, 0, sizeof(BSX.prevMMC));

	BSX.dirty         = FALSE;
	BSX.dirty2        = FALSE;
	BSX.flash_enable  = FALSE;
	BSX.write_enable  = FALSE;
	BSX.read_enable   = FALSE;
	BSX.flash_command = 0;
	BSX.old_write     = 0;
	BSX.new_write     = 0;

	BSX.out_index = 0;
	memset(BSX.output, 0, sizeof(BSX.output));

	// starting from the bios
	BSX.MMC[0x02] = BSX.MMC[0x03] = BSX.MMC[0x05] = BSX.MMC[0x06] = 0x80;
	BSX.MMC[0x09] = BSX.MMC[0x0B] = 0x80;

	BSX.MMC[0x07] = BSX.MMC[0x08] = 0x80;
	BSX.MMC[0x0E] = 0x80;

	// default register values
	BSX.PPU[0x2196 - BSXPPUBASE] = 0x10;
	BSX.PPU[0x2197 - BSXPPUBASE] = 0x80;

	// stream reset
	BSX.sat_pf_latch1_enable = BSX.sat_dt_latch1_enable = FALSE;
	BSX.sat_pf_latch2_enable = BSX.sat_dt_latch2_enable = FALSE;

	BSX.sat_stream1_loaded = BSX.sat_stream2_loaded = FALSE;
	BSX.sat_stream1_first = BSX.sat_stream2_first = FALSE;
	BSX.sat_stream1_count = BSX.sat_stream2_count = 0;

    if (BSX.sat_stream1.is_open())
        BSX.sat_stream1.close();

    if (BSX.sat_stream2.is_open())
        BSX.sat_stream2.close();

    if (Settings.BS)
	    BSX_Map();
}

void S9xBSXPostLoadState (void)
{
	uint8	temp[16];
	bool8	pd1, pd2;

	pd1 = BSX.dirty;
	pd2 = BSX.dirty2;
	memcpy(temp, BSX.MMC, sizeof(BSX.MMC));

	memcpy(BSX.MMC, BSX.prevMMC, sizeof(BSX.MMC));
	BSX_Map();

	memcpy(BSX.MMC, temp, sizeof(BSX.MMC));
	BSX.dirty  = pd1;
	BSX.dirty2 = pd2;
}

static bool valid_normal_bank (unsigned char bankbyte)
{
	switch (bankbyte)
	{
		case 32: case 33: case 48: case 49:
			return (true);
			break;
	}

	return (false);
}

static int is_bsx (unsigned char *p)
{
	if ((p[26] == 0x33 || p[26] == 0xFF) && (!p[21] || (p[21] & 131) == 128) && valid_normal_bank(p[24]))
	{
		unsigned char	m = p[22];

		if (!m && !p[23])
			return (2);

		if ((m == 0xFF && p[23] == 0xFF) || (!(m & 0xF) && ((m >> 4) - 1 < 12)))
			return (1);
	}

	return (0);
}