diff --git a/bsx.cpp b/bsx.cpp
index c317bd26..2b4454e3 100644
--- a/bsx.cpp
+++ b/bsx.cpp
@@ -199,7 +199,7 @@
 //#define BSX_DEBUG
 
 #define BIOS_SIZE	0x100000
-#define FLASH_SIZE	0x200000
+#define FLASH_SIZE	0x100000
 #define PSRAM_SIZE	0x80000
 
 #define Map			Memory.Map
@@ -231,7 +231,7 @@ static const uint8	flashcard[20] =
 {
 	0x4D, 0x00, 0x50, 0x00,	// vendor id
 	0x00, 0x00,				// ?
-	0x2B, 0x00,				// 2MB Flash (1MB = 0x2A)
+	0x1A, 0x00,				// 2MB Flash (1MB = 0x2A)
 	0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 	0x00, 0x00, 0x00, 0x00, 0x00, 0x00
 };
@@ -417,13 +417,22 @@ static void map_psram_mirror_sub (uint32 bank)
 	{
 		for (c = 0; c < 0x100; c += 16)
 		{
-			for (i = c; i < c + 8; i++)
-				Map[i + bank] = &PSRAM[(c << 11) % PSRAM_SIZE];
+			if ((bank & 0x7F) >= 0x40)
+			{
+				for (i = c; i < c + 8; i++)
+					Map[i + bank] = &PSRAM[(c << 11) % PSRAM_SIZE];
+
+				for (i = c; i < c + 8; i++)
+				{
+					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;
 
-			for (i = c; i < c + 16; i++)
+			for (i = c + 8; i < c + 16; i++)
 			{
 				BlockIsRAM[i + bank] = TRUE;
 				BlockIsROM[i + bank] = FALSE;
@@ -432,42 +441,126 @@ static void map_psram_mirror_sub (uint32 bank)
 	}
 }
 
-static void BSX_Map_PSRAM (void)
+static void BSX_Map_PSRAM(void)
 {
-	int	c;
+	int	c, i;
 
-	// Banks 70->77:0000-FFFF
-	// FIXME: could be toggled by $03
-	for (c = 0; c < 0x80; c++)
+	if (!BSX.MMC[0x02])
 	{
-		Map[c + 0x700] = &PSRAM[((c & 0x70) << 12) % PSRAM_SIZE];
-		BlockIsRAM[c + 0x700] = TRUE;
-		BlockIsROM[c + 0x700] = FALSE;
-	}
+		//LoROM Mode
+		if (!BSX.MMC[0x05] && !BSX.MMC[0x06])
+		{
+			//Map PSRAM to 00-0F/80-8F
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x00);
 
-	// Banks 20->3F:6000-7FFF mirrors 70->77:6000-7FFF
-	for (c = 0x200; c < 0x400; c += 16)
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0x80);
+		}
+		else if (BSX.MMC[0x05] && !BSX.MMC[0x06])
+		{
+			//Map PSRAM to 20-2F/A0-AF
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x20);
+
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0xA0);
+		}
+		else if (!BSX.MMC[0x05] && BSX.MMC[0x06])
+		{
+			//Map PSRAM to 40-4F/C0-CF
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x40);
+
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0xC0);
+		}
+		else
+		{
+			//Map PSRAM to 60-6F/E0-EF
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x60);
+
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0xE0);
+		}
+
+		//Map PSRAM to 70-7D/F0-FF
+		if (BSX.MMC[0x03])
+			map_psram_mirror_sub(0x70);
+
+		if (BSX.MMC[0x04])
+			map_psram_mirror_sub(0xF0);
+	}
+	else
 	{
-		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;
+		//HiROM Mode
+		if (!BSX.MMC[0x05] && !BSX.MMC[0x06])
+		{
+			//Map PSRAM to 40-47/C0-C7
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x40);
+
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0xC0);
+
+		}
+		else if (BSX.MMC[0x05] && !BSX.MMC[0x06])
+		{
+			//Map PSRAM to 50-57/D0-D7
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x50);
+
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0xD0);
+		}
+		else if (!BSX.MMC[0x05] && BSX.MMC[0x06])
+		{
+			//Map PSRAM to 60-67/E0-E7
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x60);
+
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0xE0);
+		}
+		else
+		{
+			//Map PSRAM to 70-77/F0-F7
+			if (BSX.MMC[0x03])
+				map_psram_mirror_sub(0x70);
+
+			if (BSX.MMC[0x04])
+				map_psram_mirror_sub(0xF0);
+		}
+
+		if (BSX.MMC[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.MMC[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;
+			}
+		}
 	}
-
-	if (!BSX.MMC[0x05])
-		// Banks 40->4F:0000-FFFF mirrors 70->77:0000-7FFF
-		map_psram_mirror_sub(0x40);
-
-	if (!BSX.MMC[0x06])
-		// Banks 50->5F:0000-FFFF mirrors 70->77:0000-7FFF
-		map_psram_mirror_sub(0x50);
-
-	// FIXME
-	if (!BSX.MMC[0x03])
-		// Banks 60->6F:0000-FFFF mirrors 70->77:0000-7FFF (?)
-		map_psram_mirror_sub(0x60);
 }
 
 static void BSX_Map_BIOS (void)
@@ -562,28 +655,8 @@ static void BSX_Map (void)
 
 	memcpy(BSX.prevMMC, BSX.MMC, sizeof(BSX.MMC));
 
-	// Do a quick bank change
-	if (BSX.dirty2 && !BSX.dirty)
-	{
-		BSX_Map_Dirty();
-		BSX_Map_BIOS();
-
-		BSX.dirty2 = FALSE;
-
-		Memory.map_WriteProtectROM();
-		return;
-	}
-
-	if (BSX.MMC[0x01])
-	{
-		MapROM = PSRAM;
-		FlashSize = PSRAM_SIZE;
-	}
-	else
-	{
-		MapROM = FlashROM;
-		FlashSize = FLASH_SIZE;
-	}
+	MapROM = FlashROM;
+	FlashSize = FLASH_SIZE;
 
 	BSX_Map_SNES();
 
@@ -592,12 +665,12 @@ static void BSX_Map (void)
 	else
 		BSX_Map_LoROM();
 
+	BSX_Map_FlashIO();
 	BSX_Map_PSRAM();
 	BSX_Map_SRAM();
 	BSX_Map_RAM();
 
 	BSX_Map_BIOS();
-	BSX_Map_FlashIO();
 	BSX_Map_MMC();
 
 	// Monitor new register changes
@@ -607,30 +680,24 @@ static void BSX_Map (void)
 	Memory.map_WriteProtectROM();
 }
 
-static uint8 BSX_Get_Bypass_FlashIO (uint16 offset)
+static uint8 BSX_Get_Bypass_FlashIO (uint32 offset)
 {
+	MapROM = FlashROM = Memory.ROM + Multi.cartOffsetB;
+
 	if (BSX.MMC[0x02])
-		return (MapROM[offset]);
+		return (MapROM[offset & 0x0FFFFF]);
 	else
-	{
-		if (offset < 0x8000)
-			return (MapROM[offset]);
-		else
-			return (MapROM[offset - 0x8000]);
-	}
+		return (MapROM[(offset & 0x1F0000) >> 1 | (offset & 0x7FFF)]);
 }
 
-static void BSX_Set_Bypass_FlashIO (uint16 offset, uint8 byte)
+static void BSX_Set_Bypass_FlashIO (uint32 offset, uint8 byte)
 {
+	MapROM = FlashROM = Memory.ROM + Multi.cartOffsetB;
+
 	if (BSX.MMC[0x02])
-		MapROM[offset] = byte;
+		MapROM[offset & 0x0FFFFF] = MapROM[offset & 0x0FFFFF] & byte;
 	else
-	{
-		if (offset < 0x8000)
-			MapROM[offset] = byte;
-		else
-			MapROM[offset - 0x8000] = byte;
-	}
+		MapROM[(offset & 0x1F0000) >> 1 | (offset & 0x7FFF)] = MapROM[(offset & 0x1F0000) >> 1 | (offset & 0x7FFF)] & byte;
 }
 
 uint8 S9xGetBSX (uint32 address)
@@ -640,43 +707,57 @@ uint8 S9xGetBSX (uint32 address)
 	uint8	t = 0;
 
 	// MMC
-	if ((bank >= 0x01 && bank <= 0x0E) && (offset == 0x5000))
+	if ((bank >= 0x01 && bank <= 0x0E))
 		return (BSX.MMC[bank]);
 
 	// Flash IO
-	if (bank == 0xC0)
+	if (bank >= 0xC0)
 	{
 		// default: read-through mode
-		t = BSX_Get_Bypass_FlashIO(offset);
+		t = BSX_Get_Bypass_FlashIO(address);
 
 		// note: may be more registers, purposes unknown
 		switch (offset)
 		{
-			case 0x0002:
-				if (BSX.flash_enable)
-					t = 0x80; // status register?
-				break;
+		case 0x0002:
+		case 0x8002:
+			if (BSX.flash_bsr)
+				t = 0xC0; // Page Status Register
+			break;
 
-			case 0x5555:
-				if (BSX.flash_enable)
-					t = 0x80; // ???
-				break;
+		case 0x0004:
+		case 0x8004:
+			if (BSX.flash_gsr)
+				t = 0x82; // Global Status Register
+			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;
+		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);
@@ -688,115 +769,126 @@ void S9xSetBSX (uint8 byte, uint32 address)
 	uint16	offset = address & 0xFFFF;
 
 	// MMC
-	if ((bank >= 0x01 && bank <= 0x0E) && (offset == 0x5000))
+	if ((bank >= 0x01 && bank <= 0x0E))
 	{
-		switch (bank)
-		{
-			case 0x01:
-			case 0x02:
-			case 0x03:
-			case 0x04:
-			case 0x05:
-			case 0x06:
-			case 0x09:
-			case 0x0A:
-			case 0x0B:
-			case 0x0C:
-			case 0x0D:
-				if (BSX.MMC[bank] != byte)
-				{
-					BSX.MMC[bank] = byte;
-					BSX.dirty = TRUE;
-				}
-				break;
-
-			case 0x07:
-			case 0x08:
-				if (BSX.MMC[bank] != byte)
-				{
-					BSX.MMC[bank] = byte;
-					BSX.dirty2 = TRUE;
-				}
-				break;
-
-			case 0x0E:
-				BSX.MMC[bank] = byte;
-				if (byte && (BSX.dirty || BSX.dirty2))
-					BSX_Map();
-				break;
-		}
+		BSX.MMC[bank] = byte;
+		if (bank == 0x0E)
+			BSX_Map();
 	}
 
 	// Flash IO
-	if (bank == 0xC0)
+	if (bank >= 0xC0)
 	{
-		BSX.old_write = BSX.new_write;
-		BSX.new_write = address;
-
-		// ???: double writes to the desired address will bypass
-		// flash registers
-		if (BSX.old_write == BSX.new_write && BSX.write_enable)
+		// Write to Flash
+		if (BSX.write_enable)
 		{
-			BSX_Set_Bypass_FlashIO(offset, byte);
+			BSX_Set_Bypass_FlashIO(address, byte);
+			//MapROM[address & 0x3FFFFF] = byte;
+			BSX.write_enable = false;
 			return;
 		}
 
-		// flash command handling
-		// note: incomplete
-		switch (offset)
-		{
-			case 0x0000:
-				BSX.flash_command <<= 8;
-				BSX.flash_command |= byte;
-				if ((BSX.flash_command & 0xFFFF) == 0x38D0)
-				{
-					// retrieve information about the flash card
-					BSX.flash_enable = TRUE;
-					BSX.read_enable  = TRUE;
-				}
-				break;
+		// Flash Command Handling
+		if (BSX.MMC[0xC]) {
+			//Memory Pack Type 1 & 3 & 4
+			BSX.flash_command <<= 8;
+			BSX.flash_command |= byte;
 
-			case 0x2AAA:
-				BSX.flash_command <<= 8;
-				BSX.flash_command |= byte;
-				break;
+			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 0x5555:
-				BSX.flash_command <<= 8;
-				BSX.flash_command |= byte;
+				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;
 
-				switch (BSX.flash_command & 0xFFFFFF)
-				{
-					case 0xAA55F0:
-						// turn off flash i/o
-						BSX.flash_enable = FALSE;
-						BSX.write_enable = FALSE;
-						BSX.read_enable  = FALSE;
-						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 0xAA55A0:
-						// enable writing to flash
-						BSX.old_write = 0;
-						BSX.new_write = 0;
-						BSX.flash_enable = TRUE;
-						BSX.write_enable = TRUE;
-						BSX_Map();
-						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 0xAA5570:
-						// turn on write-protection
-						BSX.write_enable = FALSE;
-						BSX_Map();
-						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 0xAA5580:
-					case 0xAA5510:
-						// ???
-						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])
+									MapROM[(address & 0x0F0000) + x] = 0xFF;
+								else
+									MapROM[((address & 0x1E0000) >> 1) + x] = 0xFF;
+							}
+							break;
 
-				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);
+									MapROM[x] = 0xFF;
+								}
+							}
+							break;
+
+						case 0x38D0: //Flashcart Reset
+							break;
+					}
+					break;
+			}
 		}
 	}
 }
@@ -1082,7 +1174,7 @@ void S9xInitBSX (void)
 			uint8	*header = r1 ? Memory.ROM + 0x7FC0 : Memory.ROM + 0xFFC0;
 
 			FlashMode = (header[0x18] & 0xEF) == 0x20 ? FALSE : TRUE;
-			FlashSize = (header[0x19] & 0x20) ? PSRAM_SIZE : FLASH_SIZE;
+			FlashSize = FLASH_SIZE;
 
 #ifdef BSX_DEBUG
 			for (int i = 0; i <= 0x1F; i++)
@@ -1145,32 +1237,11 @@ void S9xResetBSX (void)
 	memset(BSX.output, 0, sizeof(BSX.output));
 
 	// starting from the bios
-	if (BSX.bootup)
-		BSX.MMC[0x07] = BSX.MMC[0x08] = 0x80;
-	else
-	{
-		BSX.MMC[0x02] = FlashMode ? 0x80: 0;
+	BSX.MMC[0x02] = BSX.MMC[0x03] = BSX.MMC[0x05] = BSX.MMC[0x06] = 0x80;
+	BSX.MMC[0x09] = BSX.MMC[0x0B] = 0x80;
 
-		// per bios: run from psram or flash card
-		if (FlashSize == PSRAM_SIZE)
-		{
-			memcpy(PSRAM, FlashROM, PSRAM_SIZE);
-
-			BSX.MMC[0x01] = 0x80;
-			BSX.MMC[0x03] = 0x80;
-			BSX.MMC[0x04] = 0x80;
-			BSX.MMC[0x0C] = 0x80;
-			BSX.MMC[0x0D] = 0x80;
-		}
-		else
-		{
-			BSX.MMC[0x03] = 0x80;
-			BSX.MMC[0x05] = 0x80;
-			BSX.MMC[0x06] = 0x80;
-		}
-
-		BSX.MMC[0x0E] = 0x80;
-	}
+	BSX.MMC[0x07] = BSX.MMC[0x08] = 0x80;
+	BSX.MMC[0x0E] = 0x80;
 
 	BSX_Map();
 }
diff --git a/bsx.h b/bsx.h
index 5d5ea03d..ac5a2906 100644
--- a/bsx.h
+++ b/bsx.h
@@ -208,6 +208,11 @@ struct SBSX
 	uint8	MMC[16];
 	uint8	prevMMC[16];
 	uint8	test2192[32];
+
+	bool	flash_csr;
+	bool	flash_gsr;
+	bool	flash_bsr;
+	bool	flash_cmd_done;
 };
 
 extern struct SBSX	BSX;
diff --git a/gtk/src/gtk_file.cpp b/gtk/src/gtk_file.cpp
index 9c0e0009..b6607f75 100644
--- a/gtk/src/gtk_file.cpp
+++ b/gtk/src/gtk_file.cpp
@@ -422,7 +422,7 @@ S9xOpenROMDialog (void)
     {
             "*.smc", "*.SMC", "*.fig", "*.FIG", "*.sfc", "*.SFC",
             "*.jma", "*.JMA", "*.zip", "*.ZIP", "*.gd3", "*.GD3",
-            "*.swc", "*.SWC", "*.gz" , "*.GZ",
+            "*.swc", "*.SWC", "*.gz" , "*.GZ", "*.bs", "*.BS",
             NULL
     };
 
diff --git a/libretro/libretro.cpp b/libretro/libretro.cpp
index 859d3f8b..38db20e4 100644
--- a/libretro/libretro.cpp
+++ b/libretro/libretro.cpp
@@ -178,7 +178,7 @@ void retro_get_system_info(struct retro_system_info *info)
 
     info->library_name = "Snes9x";
     info->library_version = VERSION;
-    info->valid_extensions = "smc|sfc|swc|fig";
+    info->valid_extensions = "smc|sfc|swc|fig|bs";
     info->need_fullpath = false;
     info->block_extract = false;
 }
diff --git a/memmap.cpp b/memmap.cpp
index fd8f5ac1..a152268e 100644
--- a/memmap.cpp
+++ b/memmap.cpp
@@ -957,9 +957,9 @@ static void S9xDeinterleaveGD24 (int, uint8 *);
 static bool8 allASCII (uint8 *, int);
 static bool8 is_SufamiTurbo_BIOS (const uint8 *, uint32);
 static bool8 is_SufamiTurbo_Cart (const uint8 *, uint32);
-static bool8 is_SameGame_BIOS (const uint8 *, uint32);
+static bool8 is_BSCart_BIOS (const uint8 *, uint32);
 static bool8 is_SameGame_Add_On (const uint8 *, uint32);
-static bool8 is_GNEXT_BIOS (const uint8 *, uint32);
+static bool8 is_BSCartSA1_BIOS(const uint8 *, uint32);
 static bool8 is_GNEXT_Add_On (const uint8 *, uint32);
 static uint32 caCRC32 (uint8 *, uint32, uint32 crc32 = 0xffffffff);
 static uint32 ReadUPSPointer (const uint8 *, unsigned &, unsigned);
@@ -1243,10 +1243,22 @@ static bool8 is_SufamiTurbo_Cart (const uint8 *data, uint32 size)
 		return (FALSE);
 }
 
-static bool8 is_SameGame_BIOS (const uint8 *data, uint32 size)
+static bool8 is_BSCart_BIOS(const uint8 *data, uint32 size)
 {
-	if (size == 0x100000 && strncmp((char *) (data + 0xffc0), "Same Game Tsume Game", 20) == 0)
+	if ((data[0x7FB2] == 0x5A) && (data[0x7FB5] != 0x20) && (data[0x7FDA] == 0x33))
+	{
+		Memory.LoROM = TRUE;
+		Memory.HiROM = FALSE;
+
 		return (TRUE);
+	}
+	else if ((data[0xFFB2] == 0x5A) && (data[0xFFB5] != 0x20) && (data[0xFFDA] == 0x33))
+	{
+		Memory.LoROM = FALSE;
+		Memory.HiROM = TRUE;
+
+		return (TRUE);
+	}
 	else
 		return (FALSE);
 }
@@ -1259,9 +1271,14 @@ static bool8 is_SameGame_Add_On (const uint8 *data, uint32 size)
 		return (FALSE);
 }
 
-static bool8 is_GNEXT_BIOS (const uint8 *data, uint32 size)
+static bool8 is_BSCartSA1_BIOS (const uint8 *data, uint32 size)
 {
-	if (size == 0x180000 && strncmp((char *) (data + 0x7fc0), "SFC SDGUNDAMGNEXT", 17) == 0)
+	//Same basic check as BSCart
+	if (!is_BSCart_BIOS(data, size))
+		return (FALSE);
+
+	//Checks if the game is Itoi's Bass Fishing No. 1 (ZBPJ) or SD Gundam G-NEXT (ZX3J)
+	if (strncmp((char *)(data + 0x7fb2), "ZBPJ", 4) == 0 || strncmp((char *)(data + 0x7fb2), "ZX3J", 4) == 0)
 		return (TRUE);
 	else
 		return (FALSE);
@@ -1872,11 +1889,11 @@ bool8 CMemory::LoadMultiCartInt ()
         if (is_SufamiTurbo_Cart(ROM + Multi.cartOffsetA, Multi.cartSizeA))
 			Multi.cartType = 4;
 		else
-		if (is_SameGame_BIOS(ROM + Multi.cartOffsetA, Multi.cartSizeA))
-			Multi.cartType = 3;
-		else
-		if (is_GNEXT_BIOS(ROM + Multi.cartOffsetA, Multi.cartSizeA))
+		if (is_BSCartSA1_BIOS(ROM + Multi.cartOffsetA, Multi.cartSizeA))
 			Multi.cartType = 5;
+		else
+		if (is_BSCart_BIOS(ROM + Multi.cartOffsetA, Multi.cartSizeA))
+			Multi.cartType = 3;		
 	}
 	else
 	if (Multi.cartSizeB)
@@ -1924,11 +1941,8 @@ bool8 CMemory::LoadMultiCartInt ()
 			break;
 
 		case 3:
-			r = LoadSameGame();
-			break;
-
 		case 5:
-			r = LoadGNEXT();
+			r = LoadBSCart();
 			break;
 
 		default:
@@ -1992,26 +2006,31 @@ bool8 CMemory::LoadSufamiTurbo ()
 	return (TRUE);
 }
 
-bool8 CMemory::LoadSameGame ()
+bool8 CMemory::LoadBSCart ()
 {
 	Multi.sramA = SRAM;
 	Multi.sramB = NULL;
 
-	Multi.sramSizeA = ROM[0xffd8];
+	if (LoROM)
+		Multi.sramSizeA = ROM[0x7fd8];
+	else
+		Multi.sramSizeA = ROM[0xffd8];
+
 	Multi.sramMaskA = Multi.sramSizeA ? ((1 << (Multi.sramSizeA + 3)) * 128 - 1) : 0;
 	Multi.sramSizeB = 0;
 	Multi.sramMaskB = 0;
 
-	if (Multi.cartSizeB)
-	{
-		if (!is_SameGame_Add_On(ROM + Multi.cartOffsetB, Multi.cartSizeB))
-			Multi.cartSizeB = 0;
-	}
-
-	LoROM = FALSE;
-	HiROM = TRUE;
 	CalculatedSize = Multi.cartSizeA;
 
+	if (Multi.cartSizeB == 0 && Multi.cartSizeA <= (MAX_ROM_SIZE - 0x100000 - Multi.cartOffsetA))
+	{
+		//Initialize 1MB Empty Memory Pack only if cart B is cleared
+		//It does not make a Memory Pack if game is loaded like a normal ROM
+		Multi.cartOffsetB = Multi.cartOffsetA + CalculatedSize;
+		Multi.cartSizeB = 0x100000;
+		memset(Memory.ROM + Multi.cartOffsetB, 0xFF, 0x100000);
+	}
+
 	return (TRUE);
 }
 
@@ -2220,6 +2239,32 @@ bool8 CMemory::SaveSRAM (const char *filename)
 	return (FALSE);
 }
 
+bool8 CMemory::SaveMPAK (const char *filename)
+{
+	if (Settings.BS || (Multi.cartSizeB && (Multi.cartType == 3)))
+	{
+		FILE	*file;
+		int		size;
+		char	mempakName[PATH_MAX + 1];
+
+		strcpy(mempakName, filename);
+		size = 0x100000;
+		if (size)
+		{
+			file = fopen(mempakName, "wb");
+			if (file)
+			{
+				size_t	ignore;
+				ignore = fwrite((char *)Memory.ROM + Multi.cartOffsetB, size, 1, file);
+				fclose(file);
+
+				return (TRUE);
+			}
+		}
+	}
+	return (FALSE);
+}
+
 // initialization
 
 static uint32 caCRC32 (uint8 *array, uint32 size, uint32 crc32)
@@ -2566,7 +2611,7 @@ void CMemory::InitROM (void)
 			Map_ExtendedHiROMMap();
 		else
 		if (Multi.cartType == 3)
-			Map_SameGameHiROMMap();
+			Map_BSCartHiROMMap();
 		else
 			Map_HiROMMap();
     }
@@ -2584,7 +2629,7 @@ void CMemory::InitROM (void)
 		if (Settings.SA1)
 		{
 			if (Multi.cartType == 5)
-				Map_GNEXTSA1LoROMMap();
+				Map_BSSA1LoROMMap();
 			else
 				Map_SA1LoROMMap();
 		}
@@ -2598,6 +2643,13 @@ void CMemory::InitROM (void)
 		if (strncmp(ROMName, "WANDERERS FROM YS", 17) == 0)
 			Map_NoMAD1LoROMMap();
 		else
+		if (Multi.cartType == 3)
+			if (strncmp(ROMName, "SOUND NOVEL-TCOOL", 17) == 0 ||
+				strncmp(ROMName, "DERBY STALLION 96", 17) == 0)
+				Map_BSCartLoROMMap(1);
+			else
+				Map_BSCartLoROMMap(0);
+		else
 		if (strncmp(ROMName, "SOUND NOVEL-TCOOL", 17) == 0 ||
 			strncmp(ROMName, "DERBY STALLION 96", 17) == 0)
 			Map_ROM24MBSLoROMMap();
@@ -3269,9 +3321,9 @@ void CMemory::Map_SA1LoROMMap (void)
 	BWRAM = SRAM;
 }
 
-void CMemory::Map_GNEXTSA1LoROMMap (void)
+void CMemory::Map_BSSA1LoROMMap(void)
 {
-	printf("Map_GNEXTSA1LoROMMap\n");
+	printf("Map_BSSA1LoROMMap\n");
 	map_System();
 
 	map_lorom_offset(0x00, 0x3f, 0x8000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
@@ -3287,9 +3339,6 @@ void CMemory::Map_GNEXTSA1LoROMMap (void)
 	for (int c = 0x40; c < 0x80; c++)
 		map_space(c, c, 0x0000, 0xffff, SRAM + (c & 1) * 0x10000);
 
-	// FIXME: untested!
-	map_hirom_offset(0x70, 0x7f, 0x0000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
-
 	map_WRAM();
 
 	map_WriteProtectROM();
@@ -3349,26 +3398,6 @@ void CMemory::Map_ExtendedHiROMMap (void)
 	map_WriteProtectROM();
 }
 
-void CMemory::Map_SameGameHiROMMap (void)
-{
-	printf("Map_SameGameHiROMMap\n");
-	map_System();
-
-	map_hirom_offset(0x00, 0x1f, 0x8000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
-	map_hirom_offset(0x20, 0x3f, 0x8000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
-	map_hirom_offset(0x40, 0x5f, 0x0000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
-	map_hirom_offset(0x60, 0x7f, 0x0000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
-	map_hirom_offset(0x80, 0x9f, 0x8000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
-	map_hirom_offset(0xa0, 0xbf, 0x8000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
-	map_hirom_offset(0xc0, 0xdf, 0x0000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
-	map_hirom_offset(0xe0, 0xff, 0x0000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
-
-	map_HiROMSRAM();
-	map_WRAM();
-
-	map_WriteProtectROM();
-}
-
 void CMemory::Map_SPC7110HiROMMap (void)
 {
 	printf("Map_SPC7110HiROMMap\n");
@@ -3387,6 +3416,71 @@ void CMemory::Map_SPC7110HiROMMap (void)
 	map_WriteProtectROM();
 }
 
+void CMemory::Map_BSCartLoROMMap(uint8 mapping)
+{
+	printf("Map_BSCartLoROMMap\n");
+
+	BSX.MMC[0x02] = 0x00;
+	BSX.MMC[0x0C] = 0x80;
+
+	map_System();
+
+	if (mapping)
+	{
+		map_lorom_offset(0x00, 0x1f, 0x8000, 0xffff, 0x100000, 0);
+		map_lorom_offset(0x20, 0x3f, 0x8000, 0xffff, 0x100000, 0x100000);
+		map_lorom_offset(0x80, 0x9f, 0x8000, 0xffff, 0x100000, 0x200000);
+		map_lorom_offset(0xa0, 0xbf, 0x8000, 0xffff, 0x100000, 0x100000);
+	}
+	else
+	{
+		map_lorom(0x00, 0x3f, 0x8000, 0xffff, CalculatedSize);
+		map_lorom(0x40, 0x7f, 0x0000, 0x7fff, CalculatedSize);
+		map_lorom(0x80, 0xbf, 0x8000, 0xffff, CalculatedSize);
+		map_lorom(0xc0, 0xff, 0x0000, 0x7fff, CalculatedSize);
+	}
+
+	map_LoROMSRAM();
+	map_index(0xc0, 0xef, 0x0000, 0xffff, MAP_BSX, MAP_TYPE_RAM);
+	map_WRAM();
+
+	map_WriteProtectROM();
+}
+
+void CMemory::Map_BSCartHiROMMap(void)
+{
+	printf("Map_BSCartHiROMMap\n");
+
+	BSX.MMC[0x02] = 0x80;
+	BSX.MMC[0x0C] = 0x80;
+
+	map_System();
+	map_hirom_offset(0x00, 0x1f, 0x8000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
+	map_hirom_offset(0x20, 0x3f, 0x8000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
+	map_hirom_offset(0x40, 0x5f, 0x0000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
+	map_hirom_offset(0x60, 0x7f, 0x0000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
+	map_hirom_offset(0x80, 0x9f, 0x8000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
+	map_hirom_offset(0xa0, 0xbf, 0x8000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
+	map_hirom_offset(0xc0, 0xdf, 0x0000, 0xffff, Multi.cartSizeA, Multi.cartOffsetA);
+
+	if ((ROM[Multi.cartOffsetB + 0xFF00] == 0x4D)
+		&& (ROM[Multi.cartOffsetB + 0xFF02] == 0x50)
+		&& ((ROM[Multi.cartOffsetB + 0xFF06] & 0xF0) == 0x70))
+	{
+		//Type 7 Memory Pack detection - if detected, emulate it as Mask ROM
+		map_hirom_offset(0xe0, 0xff, 0x0000, 0xffff, Multi.cartSizeB, Multi.cartOffsetB);
+	}
+	else
+	{
+		map_index(0xe0, 0xff, 0x0000, 0xffff, MAP_BSX, MAP_TYPE_RAM);
+	}
+
+	map_HiROMSRAM();
+	map_WRAM();
+
+	map_WriteProtectROM();
+}
+
 // checksum
 
 uint16 CMemory::checksum_calc_sum (uint8 *data, uint32 length)
diff --git a/memmap.h b/memmap.h
index 6db01a7f..53826a98 100644
--- a/memmap.h
+++ b/memmap.h
@@ -293,13 +293,14 @@ struct CMemory
 	bool8	LoadMultiCart (const char *, const char *);
     bool8	LoadMultiCartInt ();
 	bool8	LoadSufamiTurbo ();
-	bool8	LoadSameGame ();
+	bool8	LoadBSCart ();
 	bool8	LoadGNEXT ();
 	bool8	LoadSRAM (const char *);
 	bool8	SaveSRAM (const char *);
 	void	ClearSRAM (bool8 onlyNonSavedSRAM = 0);
 	bool8	LoadSRTC (void);
 	bool8	SaveSRTC (void);
+	bool8	SaveMPAK (const char *);
 
 	char *	Safe (const char *);
 	char *	SafeANK (const char *);
@@ -335,11 +336,12 @@ struct CMemory
 	void	Map_SetaDSPLoROMMap (void);
 	void	Map_SDD1LoROMMap (void);
 	void	Map_SA1LoROMMap (void);
-	void	Map_GNEXTSA1LoROMMap (void);
+	void	Map_BSSA1LoROMMap (void);
 	void	Map_HiROMMap (void);
 	void	Map_ExtendedHiROMMap (void);
-	void	Map_SameGameHiROMMap (void);
 	void	Map_SPC7110HiROMMap (void);
+	void	Map_BSCartLoROMMap(uint8);
+	void	Map_BSCartHiROMMap(void);
 
 	uint16	checksum_calc_sum (uint8 *, uint32);
 	uint16	checksum_mirror_sum (uint8 *, uint32 &, uint32 mask = 0x800000);
diff --git a/sa1.cpp b/sa1.cpp
index 16f63490..20d45946 100644
--- a/sa1.cpp
+++ b/sa1.cpp
@@ -313,7 +313,16 @@ static void S9xSetSA1MemMap (uint32 which1, uint8 map)
 
 	for (int c = 0; c < 0x100; c += 16)
 	{
-		uint8	*block = &Memory.ROM[(map & 7) * 0x100000 + (c << 12)];
+		uint8 *block;
+		if (Multi.cartType != 5)
+			block = &Memory.ROM[(map & 7) * 0x100000 + (c << 12)];
+		else
+		{
+			if ((map & 7) < 4)
+				block = Memory.ROM + Multi.cartOffsetA + ((map & 7) * 0x100000 + (c << 12));
+			else
+				block = Memory.ROM + Multi.cartOffsetB + (((map & 7) - 4) * 0x100000 + (c << 12));
+		}
 		for (int i = c; i < c + 16; i++)
 			Memory.Map[start  + i] = SA1.Map[start  + i] = block;
 	}
@@ -321,8 +330,26 @@ static void S9xSetSA1MemMap (uint32 which1, uint8 map)
 	for (int c = 0; c < 0x200; c += 16)
 	{
         // conversion to int is needed here - map is promoted but which1 is not
-        int32 offset = (((map & 0x80) ? map : which1) & 7) * 0x100000 + (c << 11) - 0x8000;
-		uint8	*block = &Memory.ROM[offset];
+		int32 offset;
+		uint8 *block;
+		if (Multi.cartType != 5)
+		{
+			offset = (((map & 0x80) ? map : which1) & 7) * 0x100000 + (c << 11) - 0x8000;
+			block = &Memory.ROM[offset];
+		}
+		else
+		{
+			if ((map & 7) < 4)
+			{
+				offset = (((map & 0x80) ? map : which1) & 7) * 0x100000 + (c << 11) - 0x8000;
+				block = Memory.ROM + Multi.cartOffsetA + offset;
+			}
+			else
+			{
+				offset = (((map & 0x80) ? (map - 4) : which1) & 7) * 0x100000 + (c << 11) - 0x8000;
+				block = Memory.ROM + Multi.cartOffsetB + offset;
+			}			
+		}
 		for (int i = c + 8; i < c + 16; i++)
 			Memory.Map[start2 + i] = SA1.Map[start2 + i] = block;
 	}
diff --git a/win32/rsrc/resource.h b/win32/rsrc/resource.h
index 0f6bf528..07ec2620 100644
--- a/win32/rsrc/resource.h
+++ b/win32/rsrc/resource.h
@@ -496,13 +496,14 @@
 #define ID_WINDOW_SIZE_4X               40172
 #define ID_DEBUG_APU_TRACE              40173
 #define ID_EMULATION_BACKGROUNDINPUT    40174
+#define ID_SAVEMEMPACK                  40175
 
 // Next default values for new objects
 // 
 #ifdef APSTUDIO_INVOKED
 #ifndef APSTUDIO_READONLY_SYMBOLS
 #define _APS_NEXT_RESOURCE_VALUE        151
-#define _APS_NEXT_COMMAND_VALUE         40175
+#define _APS_NEXT_COMMAND_VALUE         40176
 #define _APS_NEXT_CONTROL_VALUE         3018
 #define _APS_NEXT_SYMED_VALUE           101
 #endif
diff --git a/win32/rsrc/snes9x.rc b/win32/rsrc/snes9x.rc
index a866a87d..0629f188 100644
--- a/win32/rsrc/snes9x.rc
+++ b/win32/rsrc/snes9x.rc
@@ -823,6 +823,7 @@ BEGIN
             MENUITEM "S&ave SPC Data",              ID_FILE_SAVE_SPC_DATA
             MENUITEM "Save Screenshot",             ID_SAVESCREENSHOT
             MENUITEM "Sa&ve S-RAM Data",            ID_FILE_SAVE_SRAM_DATA
+	        MENUITEM "Save Memory Pack",            ID_SAVEMEMPACK
         END
         MENUITEM "ROM Information...",          IDM_ROM_INFO
         MENUITEM SEPARATOR
diff --git a/win32/wlanguage.h b/win32/wlanguage.h
index 2c68bede..50735f57 100644
--- a/win32/wlanguage.h
+++ b/win32/wlanguage.h
@@ -597,6 +597,8 @@ Nintendo is a trade mark.")
 
 #define INFO_SAVE_SPC "Saving SPC Data."
 
+#define MPAK_SAVE_FAILED "Failed to save Memory Pack."
+
 #define CHEATS_INFO_ENABLED "Cheats enabled."
 #define CHEATS_INFO_DISABLED "Cheats disabled."
 #define CHEATS_INFO_ENABLED_NONE "Cheats enabled. (None are active.)"
diff --git a/win32/wsnes9x.cpp b/win32/wsnes9x.cpp
index 8a303486..39420e65 100644
--- a/win32/wsnes9x.cpp
+++ b/win32/wsnes9x.cpp
@@ -2248,6 +2248,17 @@ LRESULT CALLBACK WinProc(
 			if(!success)
 				S9xMessage(S9X_ERROR, S9X_FREEZE_FILE_INFO, SRM_SAVE_FAILED);
 		}	break;
+		case ID_SAVEMEMPACK: {
+			const char *filename = S9xGetFilenameInc(".bs", SRAM_DIR);
+			bool8 success = Memory.SaveMPAK(filename);
+			if (!success)
+				S9xMessage(S9X_ERROR, 0, MPAK_SAVE_FAILED);
+			else
+			{
+				sprintf(String, "Saved Memory Pack %s", filename);
+				S9xMessage(S9X_INFO, 0, String);
+			}
+		}	break;
 		case ID_FILE_RESET:
 #ifdef NETPLAY_SUPPORT
 			if (Settings.NetPlayServer)
@@ -7006,6 +7017,7 @@ void MakeExtFile(void)
 
 	out<<"smcN"<<endl<<"zipY"<<endl<<"gzY" <<endl<<"swcN"<<endl<<"figN"<<endl;
 	out<<"sfcN"<<endl;
+	out<<"bsN"<<endl;
 	out<<"jmaY";
 	out.close();
 	SetFileAttributes(TEXT("Valid.Ext"), FILE_ATTRIBUTE_ARCHIVE|FILE_ATTRIBUTE_READONLY);