avrfat16.h

butterfly MP3源代码

/**
	@file	avrfat16.h
	@brief	Fat16 Functions
	@author	Nick Lott 
	@date	September 2004

	Copyright (C) 2004 Nick Lott <[e-mail]>

	This is a simple implementation of the FAT16 file system. It is designed
	to be small for use with MP3 players and MMC cards. Currently it is 
	readonly.NOTE: The code acknowledges only the first partition on the drive.
	
	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 2
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software Foundation, 
	Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
	
	
	Target(s)...: ATmega169

	Compiler....: AVR-GCC 3.3.1; avr-libc 1.0
**/


#include "types.h"
#include "uart.h"

#define PARTITION_START		446	///< Start address of partition 1 in MBR

//-----------------------------------------------------------------------------
// FAT32 File Attributes and Types
//-----------------------------------------------------------------------------
#define FILE_ATTR_READ_ONLY   	0x01
#define FILE_ATTR_HIDDEN 		0x02
#define FILE_ATTR_SYSTEM 		0x04
#define FILE_ATTR_SYSHID		0x06
#define FILE_ATTR_VOLUME_ID 	0x08
#define FILE_ATTR_DIRECTORY		0x10
#define FILE_ATTR_ARCHIVE  		0x20
#define FILE_ATTR_LFN_TEXT		0x0F
#define FILE_ATTR_LFN_MASK		0x3F
#define FILE_HEADER_BLANK		0x00
#define FILE_HEADER_DELETED		0xE5
#define FILE_TYPE_DIR			0x10
#define FILE_TYPE_FILE			0x20
#define FILE_TYPE_MP3			0x55
#define FAT16_LDIR_Ord			0
#define FAT16_LDIR_Name1		1
#define FAT16_LDIR_Attr			11
#define FAT16_LDIR_Type			12
#define FAT16_LDIR_Chksum		13
#define FAT16_LDIR_Name2		14
#define FAT16_LDIR_FstClusLO	26
#define FAT16_LDIR_Name3		28

// For ID3 tags
#define LFN_TYPE_INDEX        208
#define LFN_TYPE_FILENAME     0x00        // No bits set
#define LFN_TYPE_ID3_TITLE    0x01        // Bit 0
#define LFN_TYPE_ID3_ARTIST   0x02        // Bit 1
#define LFN_BUFFER_LENGTH     208
#define LFN_TITLE_INDEX       0
#define LFN_TITLE_LENGTH      100      // Title length including '\0'
#define LFN_ARTIST_INDEX      100
#define LFN_ARTIST_LENGTH     100      // Artist length including '\0'
#define LFN_FREE_INDEX        200
#define LFN_FREE_LEN          8        // Currently 8 free bytes in buffer if
                                       // using ID3 tags not filenames

uint32 	FAT16_fat_begin_lba;
uint32 	FAT16_cluster_begin_lba;
uint8	FAT16_sectors_per_cluster;
uint32	FAT16_dir_first_cluster;
uint32	FAT16_root_dir_first_cluster;
uint32	FAT16_parent_dir_first_cluster;

uint8	FAT16_filetype;
uint8 	FAT16_longfilename[LFN_BUFFER_LENGTH+1]; // buffer for long filenames / ID3 tags
uint8	FAT16_LFNTitleLen;
uint8	FAT16_LFNArtistLen;
uint16 	FAT16_entryMAX; 	// Maximum entry number in FAT table. (aka file number)
uint16 	FAT16_entryMIN; 	// Minimum entry number in FAT table. (aka file number)

uint8 *FAT_buffer; // 512 byte buffer for sector reads/writes
uint8 *FAT_scratch; // 32 byte buffer for filenames and data
uint8 (*FAT_read)(uint32 lba); // pointer to read block function 
uint8 (*FAT_write)(uint32 lba);// pointer to write block function 

uint8 FAT_initFat16(void); // read MBR and bootsector and set fat variables
uint8 FAT_readCluster(uint32 cluster, uint8 sector_offset); // read a sector from a cluster
uint8 FAT_get_label(uint8 label[]); 
uint32 FAT_NextCluster(uint32 cluster); //
//uint8 FAT_NextnCluster(uint16 cluster, uint16 fatBuf[], uint8 buffer_size);
//uint8 FAT_getLongFilename(uint32 filenumber);
uint32 FAT_getNextSong(uint32 filenumber,uint32 directory);
uint32 FAT_getPrevSong(uint32 filenumber,uint32 directory);
uint8 FAT_ChkSum(uint8 *pFcbName); //8Bit checksum of 11 Byte array

/**
*   FAT_readRoot
*	@param		filenumber 32bit uInt pointing to file of interst.
*	@return		error code
*
*	Read the root directory of the disk and obtain details 
*	about FAT entry number <filenumber>
**/
uint8	FAT_readRoot(uint32 filenumber);

/**
*   FAT_read
 *	@param		filenumber 32bit uInt pointing to file of interst.
 *	@param		dir_first_entry 32bit uInt pointing to first cluster of directory
 *	@return		error code
 *
 *	Read any directory of the disk and obtain details 
 *	about FAT entry number <filenumber>
 **/
uint8	FAT_readFile(uint32 filenumber, uint32 dir_first_cluster);

/**
 *	FAT_scanDir
 *	@param	uint32 pointing to director start cluster
 *	@return	error code, 0 for okay
 *
 *	scan a directory for songs, set max, min and currentdir variables
 **/
uint8 FAT_scanDir(uint32 directory);