fat16mega128.h

移植到mega32上面的fat16代码实现了

//############################################################################
//
// File Name	: 'fat.c'
// Title		: FAT16 file system driver
// Author		: Zoltan Gradwohl
// Date			: 28/07/2005
// Revised		: 28/07/2005
// Version		: 1.0
// Target MCU	: ATmega128 (2K Byte Internal SRAM required)
// Editor Tabs	: 4
//
//
// NOTE: This code is currently below version 1.0, and therefore is considered
// to be lacking in some functionality or documentation, or may not be fully
// tested.  Nonetheless, you can expect most functions to work.
//
// This code is distributed under the GNU Public License
//		which can be found at http://www.gnu.org/licenses/gpl.txt
//
//############################################################################

#ifndef FAT_H
#define FAT_H

#include "global.h"


// Some useful cluster numbers
#define MSDOSFSROOT     0               // cluster 0 means the root dir
#define CLUST_FREE      0               // cluster 0 also means a free cluster
#define MSDOSFSFREE     CLUST_FREE
#define CLUST_FIRST     2               // first legal cluster number
#define CLUST_RSRVD     0xfffffff6      // reserved cluster range
#define CLUST_BAD       0xfffffff7      // a cluster with a defect
#define CLUST_EOFS      0xfffffff8      // start of eof cluster range
#define CLUST_EOFE      0xffffffff      // end of eof cluster range

#define FAT12_MASK      0x00000fff      // mask for 12 bit cluster numbers
#define FAT16_MASK      0x0000ffff      // mask for 16 bit cluster numbers
#define FAT32_MASK      0x0fffffff      // mask for FAT32 cluster numbers


// Partition Type used in the partition record
#define PART_TYPE_UNKNOWN		0x00
#define PART_TYPE_FAT12			0x01
#define PART_TYPE_XENIX			0x02
#define PART_TYPE_DOSFAT16		0x04
#define PART_TYPE_EXTDOS		0x05
#define PART_TYPE_FAT16			0x06
#define PART_TYPE_NTFS			0x07
#define PART_TYPE_FAT32			0x0B
#define PART_TYPE_FAT32LBA		0x0C
#define PART_TYPE_FAT16LBA		0x0E
#define PART_TYPE_EXTDOSLBA		0x0F
#define PART_TYPE_ONTRACK		0x33
#define PART_TYPE_NOVELL		0x40
#define PART_TYPE_PCIX			0x4B
#define PART_TYPE_PHOENIXSAVE	0xA0
#define PART_TYPE_CPM			0xDB
#define PART_TYPE_DBFS			0xE0
#define PART_TYPE_BBT			0xFF




// Maximum filename length in Win95
// Note: Must be < sizeof(dirent.d_name)
#define WIN_MAXLEN      255

// This is the format of the contents of the deTime field in the direntry
// structure.
// We don't use bitfields because we don't know how compilers for
// arbitrary machines will lay them out.
#define DT_2SECONDS_MASK        0x1F    // seconds divided by 2
#define DT_2SECONDS_SHIFT       0
#define DT_MINUTES_MASK         0x7E0   // minutes
#define DT_MINUTES_SHIFT        5
#define DT_HOURS_MASK           0xF800  // hours
#define DT_HOURS_SHIFT          11


// This is the format of the contents of the deDate field in the direntry
// structure.
#define DD_DAY_MASK             0x1F    // day of month
#define DD_DAY_SHIFT            0
#define DD_MONTH_MASK           0x1E0   // month
#define DD_MONTH_SHIFT          5
#define DD_YEAR_MASK            0xFE00  // year - 1980
#define DD_YEAR_SHIFT           9


#define CONTINUE 0
#define OVERWRITE 1



// Prototypes
uint8_t fatInit(void);

void FAT16_Search 		(  	char   		*Name2Find,				// In: 		File name to find
							int8_t  	select	);	  			// In: 		Select operation: overwrite or contiue data
void FAT16_Write_Data 	(  	uint32_t 	Data );	  				// In:
void FAT16_Finish_Data	(   void );							//


int8_t fatSearch_File 	(   char 	   	*Name2Find_,	  		// In: 		File name to find
							uint16_t  	*FAT_Entry_, 			// Return:  FAT entry where data starts
							uint32_t  	*FileSize_,    			// Return: 	Return filesize
							uint32_t  	*Sector_,				// Return: 	Sector which contains file size inforation
							uint8_t   	*SubSector_,   			// Return: 	Return which of the 16 32byte long SubSectors contains the file size
							uint32_t	*DataSector,  			// Return:  Return sector where data starts
							uint8_t   	*Attributes_,  			// Return: 	Return Attribute Dir, archive, hidden, system, volume ...
							uint8_t   	*Buffer_);				// In: 		Buffer to use
int8_t fatGetDirEntry 	(	char     	*Name2Find,				// In: 		String with name to find in sector
							uint16_t 	*FAT_Entry,				// In/Ret:  FAT entry where data starts
							uint32_t 	*FileSize,    			// Return: 	Return filesize
							uint32_t 	*Sector,				// Return: 	Sector which contains file size inforation
							uint8_t  	*SubSector,   			// Return: 	Return which of the 16 32byte long SubSectors contains the file size
							uint32_t	*DataSector,  			// Return:  Return sector where data starts
							uint8_t  	*Attributes,  			// Return: 	Return Attribute Dir, archive, hidden, system, volume ...
							uint8_t  	*Buffer);				// In:		Select buffer to use

void fatLoad			(	uint16_t 	*FATEntry, 				// Angabe Start cluster
							uint32_t 	*Adr_FirstSectorOfCluster,// Rückgabe Adresse des ersten Sectors des gew?hlten Clusters
																// Rückgabe des n?chsten FAT- Eintrags auf dem das aktuelle FAT-Eintrag zeigt
							uint8_t  	*Buffer);				// In:		Select buffer to use
void PrintDOSLine		(	char 		*DirNameAdress,
							uint16_t 	CreateDate,
							uint16_t 	CreateTime,
							uint32_t 	FileSize,
							uint8_t 	Dir_Or_Data);
void fatRead_File 		(	uint16_t 	*FATEntry, 				// In:  	Start clusters of file
							uint32_t 	*Sector_Adress,			// In:
							uint32_t 	*FileSize, 				// In:
							uint8_t  	*Buffer);				// In:		Select buffer to use

void fatWrite			(	uint16_t 	*FATEntry, 				// In/Ret: 	Angabe Start cluster , Rückgabe des n?chsten FAT- Eintrags auf dem das aktuelle FAT-Eintrag zeigt
							uint32_t 	*Adr_FirstSectorOfCluster,// Return: Rückgabe Adresse des ersten Sectors des gew?hlten Clusters
							uint8_t  	*Buffer );				// In:		Select buffer to use
void fatWrite_Data 		(	uint32_t	*data,					// In:
							uint16_t 	*FATEntry,				// In/Ret:
							uint32_t 	*DataSector,			// In/Ret:
							uint32_t 	*FileSize, 				// In/Ret:
							uint8_t  	*Buffer);				// In:
void fatWrite_Continue (	uint16_t  	*FATEntry,				// In/Ret:  FAT entry where data starts
							uint32_t 	*SectorAdress,			// Return:  Current data sector adress
							uint32_t 	*FileSize,    			// Return: 	Return filesize
							uint8_t  	*Buffer);				// In:		Select buffer to use

void fat_Delete 		(	uint16_t 	*FATEntry,				// In/Ret:  FAT entry where data starts
							uint32_t 	*FileSize,    			// Return: 	Return filesize
							uint32_t 	*Sector,				// In: 		Sector which contains file size inforation
							uint8_t  	*SubSector,				// In: 		Return which of the 16 32byte long SubSectors contains the file size
							uint32_t  	*DataSector,			// Return:	Sector where data starts
							uint8_t  	*Buffer);				// In:		Select buffer to use
void fat_Init_File 		(	uint16_t  	*FATEntry,				// In/Ret:  FAT entry where data starts
							uint32_t 	*FileSize,    			// In: 		Filesize
							uint32_t 	*Sector,				// In: 		Sector which contains file size inforation
							uint8_t  	*SubSector,				// In: 		Return which of the 16 32byte long SubSectors contains the file size
							uint32_t  	*DataSector,			// Return:	Sector where data starts
							uint8_t  	*Buffer);				// In:		Select buffer to use
void Fat_Test 			( 	void );

#define READROOTDIR 0
// number of directory entries in one sector
#define DIRENTRIES_PER_SECTOR	0x10


//############################################################################
// Structure of a dos directory entry.
typedef struct
//############################################################################
{
		uint8_t		deName[8];      // filename, blank filled
#define SLOT_EMPTY      0x00            // slot has never been used
#define SLOT_E5         0x05            // the real value is 0xe5
#define SLOT_DELETED    0xe5            // file in this slot deleted
#define SLOT_DNt_Entry  0x2E            // 'Dot' entry;
		uint8_t		deExtension[3]; // extension, blank filled
		uint8_t		deAttributes;   // file attributes
#define ATTR_NORMAL     0x00            // normal file
#define ATTR_READONLY   0x01            // file is readonly
#define ATTR_HIDDEN     0x02            // file is hidden
#define ATTR_SYSTEM     0x04            // file is a system file
#define ATTR_VOLUME     0x08            // entry is a volume label
#define ATTR_LONG_FILENAME	0x0f		// this is a long filename entry
#define ATTR_DIRECTORY  0x10            // entry is a directory name
#define ATTR_ARCHIVE    0x20            // file is new or modified
		uint8_t        deLowerCase;    // NT VFAT lower case flags
#define LCASE_BASE      0x08            // filename base in lower case
#define LCASE_EXT       0x10            // filename extension in lower case
		uint8_t        deCHundredth;   // hundredth of seconds in CTime
		uint16_t       deCTime;     	// create time
		uint16_t       deCDate;     	// create date
		uint16_t       deADate;     	// access date
		uint16_t       deHighClust; 	// high uint8_ts of cluster number
		uint16_t       deMTime;     	// last update time
		uint16_t       deMDate;     	// last update date
		uint16_t       deStartCluster; // starting cluster of file
		uint32_t       deFileSize;  	// size of file
}DirEntry;

//############################################################################
// Structure of a Win95 long name directory entry
typedef struct
//############################################################################
{
		uint8_t		weCnt;
#define WIN_LAST        0x40
#define WIN_CNT         0x3f
		uint8_t		wePart1[10];
		uint8_t		weAttributes;
#define ATTR_WIN95      0x0f  // ATTR_LONG_FILENAME
		uint8_t		weReserved1;
		uint8_t		weChksum;
		uint8_t		wePart2[12];
		uint16_t       weReserved2;
		uint8_t		wePart3[4];
}LongDirEntry;

//############################################################################
typedef struct   					// The 2-byte numbers are stored little endian (low order byte first).
//############################################################################
{
	// Code to jump to the bootstrap code
	uint8_t  		bsjmpBoot[3]; 		// 0-2   Jump to bootstrap (E.g. eb 3c 90; on i86: JMP 003E NOP. One finds either eb xx 90, or e9 xx xx. The position of the bootstrap varies.)
	// OS Name
	char    		bsOEMName[8]; 		// 3-10  OEM name/version (E.g. "IBM  3.3", "IBM 20.0", "MSDOS5.0", "MSWIN4.0".
	// BIOS Parameter Block
	uint16_t   	bsBytesPerSec;		// 11-12 Number of bytes per sector (512). Must be one of 512, 1024, 2048, 4096.
	uint8_t		bsSecPerClus;		// 13    Number of sectors per cluster (1). Must be one of 1, 2, 4, 8, 16, 32, 64, 128.
	uint16_t		bsRsvdSecCnt;   	// 14-15 Number of reserved sectors (1). FAT12 and FAT16 use 1. FAT32 uses 32.
	uint8_t		bsNumFATs;			// 16    Number of FAT copies (2)
	uint16_t		bsRootEntCnt; 		// 17-18 Number of root directory entries (224). 0 for FAT32. 512 is recommended for FAT16.
	uint16_t		bsTotSec16; 		// 19-20 Total number of sectors in the filesystem (2880). (in case the partition is not FAT32 and smaller than 32 MB)
	uint8_t		bsMedia;			// 21    Media descriptor type ->  For hard disks:  Value 0xF8  ,  DOS version 2.0
	uint16_t		bsNrSeProFAT;     	// 22-23 Number of sectors per FAT (9). 0 for FAT32.
	uint16_t		bsSecPerTrk;		// 24-25 Number of sectors per track (12)
	uint16_t		bsNumHeads; 		// 26-27 Number of heads (2, for a double-sided diskette)
	uint32_t		bsHiddSec;			// 28-31 Number of hidden sectors (0)
	uint32_t		bsTotSec32; 		// 32-35 Number of total sectors (in case the total was not given in bytes 19-20)
	// Ext. BIOS Parameter Block
	uint8_t		bsLogDrvNr;			// 36    Logical Drive Number (for use with INT 13, e.g. 0 or 0x80)
	uint8_t		bsReserved;			// 37    Reserved (Earlier: Current Head, the track containing the Boot Record) Used by Windows NT: bit 0: need disk check; bit 1: need surface scan
	uint8_t		bsExtSign;			// 38    Extended signature (0x29)  Indicates that the three following fields are present. Windows NT recognizes either 0x28 or 0x29.
	uint32_t		bsParSerNr; 		// 39-42 Serial number of partition
	uint8_t		bsVolLbl[11]; 		// 43-53 Volume label or "NO NAME    "
	uint8_t		bsFileSysType[8]; 	// 54-61 Filesystem type (E.g. "FAT12   ", "FAT16   ", "FAT     ", or all zero.)
	// Bootstrap Code
	uint8_t		bsBootstrap[448]; 	// Bootstrap
	// Signature
	uint16_t		bsSignature; 		// 510-511 Signature 55 aa
}BootSector;


//############################################################################
typedef struct // length 16 uint8_ts
//############################################################################
{
	uint8_t 		prIsActive;		// Current State of Partition x80 indicates active partition
	uint8_t 		prStartHead;	// Beginning of Partition - Head
	uint16_t 		prStartCylSect;	// Beginning of Partition - Cylinder/Sector (See Below)
	uint8_t 		prPartType;		// Type of Partition
	uint8_t 		prEndHead;		// End of Partition - Head
	uint16_t 		prEndCylSect;	// End of Partition - Cylinder/Sector
	uint32_t 		prStartLBA;		// Number of Sectors Between the MBR and the First Sector in the Partition
	uint32_t 		prSize;			// Number of Sectors in the Partition
}PartitionEntry;

//############################################################################
typedef struct   					// The 2-byte numbers are stored little endian (low order byte first).
//############################################################################
{
	uint8_t  		mbBootCode[446]; 			// Code to jump to the bootstrap code
	PartitionEntry  mbPartitionEntries[4];		// 1st..4th Partition Entry
	uint16_t		mbExecutableMarker; 		//Executable Marker (55h AAh)  	2 Bytes
#define BOOTSIG0        0xaa55
}MasterBootSector;




//############################################################################
union FAT16_Buffer
//############################################################################
{
    // data layer one 	- (unformated data)
	uint8_t FATBuffer[512];
	// data layer two   - (Master Boot Record)
	MasterBootSector MBS;
	// data layer three - (Volume Boot Record)
	BootSector BootSec;
	// data layer four  - (512byte partitioned in 20 SubSectors) Type: DirEntry
	DirEntry direntries[DIRENTRIES_PER_SECTOR];
	// data layer five  - (512byte partitioned in 20 SubSectors) Type: Long Name DirEntry
	LongDirEntry longdirentries[DIRENTRIES_PER_SECTOR];
	// data layer six   - (data to write on mmc [32bit]~>128 )
	uint32_t FATData[128];
};





#endif