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diff --git a/Core/FatFormatter.cpp b/Core/FatFormatter.cpp
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+++ b/Core/FatFormatter.cpp
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+/*
+ Legal Notice: Some portions of the source code contained in this file were
+ derived from the source code of Encryption for the Masses 2.02a, which is
+ Copyright (c) 1998-2000 Paul Le Roux and which is governed by the 'License
+ Agreement for Encryption for the Masses'. Modifications and additions to
+ the original source code (contained in this file) and all other portions
+ of this file are Copyright (c) 2003-2010 TrueCrypt Developers Association
+ and are governed by the TrueCrypt License 3.0 the full text of which is
+ contained in the file License.txt included in TrueCrypt binary and source
+ code distribution packages. */
+
+#include "Common/Tcdefs.h"
+#include "Platform/Platform.h"
+#include "Volume/VolumeHeader.h"
+#include "FatFormatter.h"
+#include "RandomNumberGenerator.h"
+
+namespace TrueCrypt
+{
+	struct fatparams
+	{
+		char volume_name[11];
+		uint32 num_sectors;	/* total number of sectors */
+		uint32 cluster_count;	/* number of clusters */
+		uint32 size_root_dir;	/* size of the root directory in bytes */
+		uint32 size_fat;		/* size of FAT */
+		uint32 fats;
+		uint32 media;
+		uint32 cluster_size;
+		uint32 fat_length;
+		uint16 dir_entries;
+		uint16 sector_size;
+		uint32 hidden;
+		uint16 reserved;
+		uint16 sectors;
+		uint32 total_sect;
+
+		uint16 heads;
+		uint16 secs_track;
+
+	};
+
+	static void GetFatParams (fatparams * ft)
+	{
+		uint64 volumeSize = (uint64) ft->num_sectors * ft->sector_size;
+		unsigned int fatsecs;
+
+		if(ft->cluster_size == 0)	// 'Default' cluster size
+		{
+			uint32 clusterSize;
+
+			// Determine optimal cluster size to minimize FAT size (mounting delay), maximize number of files, keep 4 KB alignment, etc.
+			if (volumeSize >= 2 * BYTES_PER_TB)
+				clusterSize = 256 * BYTES_PER_KB;
+			else if (volumeSize >= 512 * BYTES_PER_GB)
+				clusterSize = 128 * BYTES_PER_KB;
+			else if (volumeSize >= 128 * BYTES_PER_GB)
+				clusterSize = 64 * BYTES_PER_KB;
+			else if (volumeSize >= 64 * BYTES_PER_GB)
+				clusterSize = 32 * BYTES_PER_KB;
+			else if (volumeSize >= 32 * BYTES_PER_GB)
+				clusterSize = 16 * BYTES_PER_KB;
+			else if (volumeSize >= 16 * BYTES_PER_GB)
+				clusterSize = 8 * BYTES_PER_KB;
+			else if (volumeSize >= 512 * BYTES_PER_MB)
+				clusterSize = 4 * BYTES_PER_KB;
+			else if (volumeSize >= 256 * BYTES_PER_MB)
+				clusterSize = 2 * BYTES_PER_KB;
+			else if (volumeSize >= 1 * BYTES_PER_MB)
+				clusterSize = 1 * BYTES_PER_KB;
+			else
+				clusterSize = 512;
+
+			ft->cluster_size = clusterSize / ft->sector_size;
+
+			if (ft->cluster_size == 0)
+				ft->cluster_size = 1;
+
+			if (ft->cluster_size * ft->sector_size > TC_MAX_FAT_CLUSTER_SIZE)
+				ft->cluster_size = TC_MAX_FAT_CLUSTER_SIZE / ft->sector_size;
+
+			if (ft->cluster_size > 128)
+				ft->cluster_size = 128;
+		}
+
+		if (volumeSize <= TC_MAX_FAT_CLUSTER_SIZE * 4)
+			ft->cluster_size = 1;
+
+		// Geometry always set to SECTORS/1/1
+		ft->secs_track = 1; 
+		ft->heads = 1; 
+
+		ft->dir_entries = 512;
+		ft->fats = 2;
+		ft->media = 0xf8;
+		ft->hidden = 0;
+
+		ft->size_root_dir = ft->dir_entries * 32;
+
+		// FAT12
+		ft->size_fat = 12;
+		ft->reserved = 2;
+		fatsecs = ft->num_sectors - (ft->size_root_dir + ft->sector_size - 1) / ft->sector_size - ft->reserved;
+		ft->cluster_count = (int) (((int64) fatsecs * ft->sector_size) / (ft->cluster_size * ft->sector_size));
+		ft->fat_length = (((ft->cluster_count * 3 + 1) >> 1) + ft->sector_size - 1) / ft->sector_size;
+
+		if (ft->cluster_count >= 4085) // FAT16
+		{
+			ft->size_fat = 16;
+			ft->reserved = 2;
+			fatsecs = ft->num_sectors - (ft->size_root_dir + ft->sector_size - 1) / ft->sector_size - ft->reserved;
+			ft->cluster_count = (int) (((int64) fatsecs * ft->sector_size) / (ft->cluster_size * ft->sector_size));
+			ft->fat_length = (ft->cluster_count * 2 + ft->sector_size - 1) / ft->sector_size;
+		}
+
+		if(ft->cluster_count >= 65525) // FAT32
+		{
+			ft->size_fat = 32;
+			ft->reserved = 32 - 1;
+
+			do
+			{
+				ft->reserved++;
+
+				fatsecs = ft->num_sectors - ft->reserved;
+				ft->size_root_dir = ft->cluster_size * ft->sector_size;
+				ft->cluster_count = (int) (((int64) fatsecs * ft->sector_size) / (ft->cluster_size * ft->sector_size));
+				ft->fat_length = (ft->cluster_count * 4 + ft->sector_size - 1) / ft->sector_size;
+
+				// Align data area on TC_MAX_VOLUME_SECTOR_SIZE
+
+			} while (ft->sector_size == TC_SECTOR_SIZE_LEGACY
+				&& (ft->reserved * ft->sector_size + ft->fat_length * ft->fats * ft->sector_size) % TC_MAX_VOLUME_SECTOR_SIZE != 0);
+		}
+
+		ft->cluster_count -= ft->fat_length * ft->fats / ft->cluster_size;
+
+		if (ft->num_sectors >= 65536 || ft->size_fat == 32)
+		{
+			ft->sectors = 0;
+			ft->total_sect = ft->num_sectors;
+		}
+		else
+		{
+			ft->sectors = (uint16) ft->num_sectors;
+			ft->total_sect = 0;
+		}
+	}
+
+	static void PutBoot (fatparams * ft, byte *boot, uint32 volumeId)
+	{
+		int cnt = 0;
+
+		boot[cnt++] = 0xeb;	/* boot jump */
+		boot[cnt++] = 0x3c;
+		boot[cnt++] = 0x90;
+		memcpy (boot + cnt, "MSDOS5.0", 8); /* system id */
+		cnt += 8;
+		*(int16 *)(boot + cnt) = Endian::Little (ft->sector_size);	/* bytes per sector */
+		cnt += 2;
+		boot[cnt++] = (int8) ft->cluster_size;			/* sectors per cluster */
+		*(int16 *)(boot + cnt) = Endian::Little (ft->reserved);		/* reserved sectors */
+		cnt += 2;
+		boot[cnt++] = (int8) ft->fats;					/* 2 fats */
+
+		if(ft->size_fat == 32)
+		{
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x00;
+		}
+		else
+		{
+			*(int16 *)(boot + cnt) = Endian::Little (ft->dir_entries);	/* 512 root entries */
+			cnt += 2;
+		}
+
+		*(int16 *)(boot + cnt) = Endian::Little (ft->sectors);		/* # sectors */
+		cnt += 2;
+		boot[cnt++] = (int8) ft->media;					/* media byte */
+
+		if(ft->size_fat == 32)	
+		{
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x00;
+		}
+		else 
+		{ 
+			*(uint16 *)(boot + cnt) = Endian::Little ((uint16) ft->fat_length);	/* fat size */
+			cnt += 2;
+		}
+
+		*(int16 *)(boot + cnt) = Endian::Little (ft->secs_track);	/* # sectors per track */
+		cnt += 2;
+		*(int16 *)(boot + cnt) = Endian::Little (ft->heads);			/* # heads */
+		cnt += 2;
+		*(int32 *)(boot + cnt) = Endian::Little (ft->hidden);		/* # hidden sectors */
+		cnt += 4;
+		*(int32 *)(boot + cnt) = Endian::Little (ft->total_sect);	/* # huge sectors */
+		cnt += 4;
+
+		if(ft->size_fat == 32)
+		{
+			*(int32 *)(boot + cnt) = Endian::Little (ft->fat_length); cnt += 4;	/* fat size 32 */
+			boot[cnt++] = 0x00;	/* ExtFlags */
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x00;	/* FSVer */
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x02;	/* RootClus */
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x01;	/* FSInfo */
+			boot[cnt++] = 0x00;
+			boot[cnt++] = 0x06;	/* BkBootSec */
+			boot[cnt++] = 0x00;
+			memset(boot+cnt, 0, 12); cnt+=12;	/* Reserved */
+		}
+
+		boot[cnt++] = 0x00;	/* drive number */   // FIXED 80 > 00
+		boot[cnt++] = 0x00;	/* reserved */
+		boot[cnt++] = 0x29;	/* boot sig */
+
+		*(int32 *)(boot + cnt) = volumeId;
+		cnt += 4;
+
+		memcpy (boot + cnt, ft->volume_name, 11);	/* vol title */
+		cnt += 11;
+
+		switch(ft->size_fat) /* filesystem type */
+		{
+		case 12: memcpy (boot + cnt, "FAT12   ", 8); break;
+		case 16: memcpy (boot + cnt, "FAT16   ", 8); break;
+		case 32: memcpy (boot + cnt, "FAT32   ", 8); break;
+		}
+		cnt += 8;
+
+		memset (boot + cnt, 0, ft->size_fat==32 ? 420:448);	/* boot code */
+		cnt += ft->size_fat==32 ? 420:448;
+		boot[cnt++] = 0x55;
+		boot[cnt++] = 0xaa;	/* boot sig */
+	}
+
+
+	/* FAT32 FSInfo */
+	static void PutFSInfo (byte *sector, fatparams *ft)
+	{
+		memset (sector, 0, ft->sector_size);
+		sector[3] = 0x41; /* LeadSig */
+		sector[2] = 0x61; 
+		sector[1] = 0x52; 
+		sector[0] = 0x52; 
+		sector[484+3] = 0x61; /* StrucSig */
+		sector[484+2] = 0x41; 
+		sector[484+1] = 0x72; 
+		sector[484+0] = 0x72; 
+
+		// Free cluster count
+		*(uint32 *)(sector + 488) = Endian::Little (ft->cluster_count - ft->size_root_dir / ft->sector_size / ft->cluster_size);
+
+		// Next free cluster
+		*(uint32 *)(sector + 492) = Endian::Little ((uint32) 2);
+
+		sector[508+3] = 0xaa; /* TrailSig */
+		sector[508+2] = 0x55;
+		sector[508+1] = 0x00;
+		sector[508+0] = 0x00;
+	}
+
+	void FatFormatter::Format (WriteSectorCallback &writeSector, uint64 deviceSize, uint32 clusterSize, uint32 sectorSize)
+	{
+		fatparams fatParams;
+
+#if TC_MAX_VOLUME_SECTOR_SIZE > 0xFFFF
+#error TC_MAX_VOLUME_SECTOR_SIZE > 0xFFFF
+#endif
+		fatParams.sector_size = (uint16) sectorSize;
+
+		if (deviceSize / fatParams.sector_size > 0xffffFFFF)
+			throw ParameterIncorrect (SRC_POS);
+
+		fatParams.num_sectors = (uint32) (deviceSize / fatParams.sector_size);
+		fatParams.cluster_size = clusterSize / fatParams.sector_size;
+		memcpy (fatParams.volume_name, "NO NAME    ", 11);
+		GetFatParams (&fatParams); 
+		fatparams *ft = &fatParams;
+
+		SecureBuffer sector (ft->sector_size);
+		uint32 sectorNumber = 0;
+
+		/* Write the data area */
+
+		sector.Zero();
+
+		uint32 volumeId;
+		RandomNumberGenerator::GetDataFast (BufferPtr ((byte *) &volumeId, sizeof (volumeId)));
+
+		PutBoot (ft, (byte *) sector, volumeId);
+		writeSector (sector); ++sectorNumber;
+
+		/* fat32 boot area */
+		if (ft->size_fat == 32)				
+		{
+			/* fsinfo */
+			PutFSInfo((byte *) sector, ft);
+			writeSector (sector); ++sectorNumber;
+
+			/* reserved */
+			while (sectorNumber < 6)
+			{
+				sector.Zero();
+				sector[508+3] = 0xaa; /* TrailSig */
+				sector[508+2] = 0x55;
+				writeSector (sector); ++sectorNumber;
+			}
+
+			/* bootsector backup */
+			sector.Zero();
+			PutBoot (ft, (byte *) sector, volumeId);
+			writeSector (sector); ++sectorNumber;
+
+			PutFSInfo((byte *) sector, ft);
+			writeSector (sector); ++sectorNumber;
+		}
+
+		/* reserved */
+		while (sectorNumber < (uint32)ft->reserved)
+		{
+			sector.Zero();
+			writeSector (sector); ++sectorNumber;
+		}
+
+		/* write fat */
+		for (uint32 x = 1; x <= ft->fats; x++)
+		{
+			for (uint32 n = 0; n < ft->fat_length; n++)
+			{
+				sector.Zero();
+
+				if (n == 0)
+				{
+					byte fat_sig[12];
+					if (ft->size_fat == 32)
+					{
+						fat_sig[0] = (byte) ft->media;
+						fat_sig[1] = fat_sig[2] = 0xff;
+						fat_sig[3] = 0x0f;
+						fat_sig[4] = fat_sig[5] = fat_sig[6] = 0xff;
+						fat_sig[7] = 0x0f;
+						fat_sig[8] = fat_sig[9] = fat_sig[10] = 0xff;
+						fat_sig[11] = 0x0f;
+						memcpy (sector, fat_sig, 12);
+					}				
+					else if (ft->size_fat == 16)
+					{
+						fat_sig[0] = (byte) ft->media;
+						fat_sig[1] = 0xff;
+						fat_sig[2] = 0xff;
+						fat_sig[3] = 0xff;
+						memcpy (sector, fat_sig, 4);
+					}
+					else if (ft->size_fat == 12)
+					{
+						fat_sig[0] = (byte) ft->media;
+						fat_sig[1] = 0xff;
+						fat_sig[2] = 0xff;
+						fat_sig[3] = 0x00;
+						memcpy (sector, fat_sig, 4);
+					}
+				}
+
+				if (!writeSector (sector))
+					return;
+			}
+		}
+
+		/* write rootdir */
+		for (uint32 x = 0; x < ft->size_root_dir / ft->sector_size; x++)
+		{
+			sector.Zero();
+			if (!writeSector (sector))
+				return;
+		}
+	}
+}