Fat16 Functions. More...

#include <avr/io.h>
#include <avr/pgmspace.h>
#include <avr/interrupt.h>
#include "types.h"
#include "avrfat16.h"
#include "utils.h"

Include dependency graph for avrfat16.c:

Go to the source code of this file.

Defines
#define	FLG_ROOTDIR 0
Functions
uint8	FAT_initFat16 (void)
	FAT_initFat16.
uint8	FAT_readCluster (uint32 cluster, uint8 sector_offset)
	FAT_get_label.
uint32	FAT_NextCluster (uint32 cluster)
	FAT_NextCluster.
uint8	FAT_readFile (uint32 filenumber, uint32 dir_first_sector)
	FAT_read.
uint32	FAT_getNextSong (uint32 filenumber, uint32 dir_lba)
	FAT_readRoot.
uint32	FAT_getPrevSong (uint32 filenumber, uint32 dir_lba)
	GetPrevSong.
uint32	FAT_getNumberedSong (char songNumber, uint32 dir_lba)
	GetNumberedSong.
uint8	FAT_ChkSum (uint8 *pFcbName)
	FAT_ChkSum()
uint32	FAT_cluster2lba (uint32 cluster)
	FAT_cluster2lba.
uint32	FAT_lba2cluster (uint32 lba_addr)
	FAT_lba2cluster.
uint8	FAT_scanDir_lba (uint32 lba_addr)
	FAT_scanDir_lba.
uint32	FAT_getParentDir (uint32 lba_addr)
	FAT_getParentDir.
void	FAT_Scratch2Cluster ()
	FAT_Scratch2Cluster.
Variables
uint32	gCluster
	current sector (cluster) in song main.h

Detailed Description

Fat16 Functions.

Author:: Nick Lott

Date:: September 2004

Id:: avrfat16.c,v 1.30 2009/01/19 23:36:09 brokentoaster Exp

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

Definition in file avrfat16.c.

Define Documentation

#define FLG_ROOTDIR 0

Referenced by FAT_readFile().

Function Documentation

uint8 FAT_ChkSum ( uint8 * pFcbName )

FAT_ChkSum()

Returns an unsigned byte check sum computed on an unsignedbyte array. The array must be 11 bytes long and is assumed to contain a name stored in the format of a MS-DOS directory entry.

Parameters:

pFcbName Pointer to an unsigned byte array assumed to be 11 bytes long. An 8-bit unsigned checksum of the array pointed to by pFcbName.

Definition at line 748 of file avrfat16.c.

Referenced by FAT_readFile().

uint32 FAT_cluster2lba ( uint32 cluster )

FAT_cluster2lba.

Calculate the sector address of a cluster.

Parameters:

uint32 pointing to cluster

Returns:: lba of first sector in cluster

Definition at line 786 of file avrfat16.c.

References FAT16_cluster_begin_lba, and FAT16_sectors_per_cluster.

Referenced by FAT_getParentDir(), FAT_readFile(), and handle_interface().

uint32 FAT_getNextSong	(	uint32	filenumber,
		uint32	dir_lba
	)

FAT_readRoot.

Read the root directory of the disk and obtain details about FAT entry number <filenumber>

Parameters:

filenumber 32bit uInt pointing to file of interst.

Returns:: error code GetNextSong

Parameters:

filenumber	uint32 index of current file in directory
dir_lba	uint32 lba of directory to search

Returns:: new filenumber or 0=err

Definition at line 627 of file avrfat16.c.

References FAT16_entryMAX, and FAT_readFile().

Referenced by FAT_scanDir_lba(), handle_interface(), restore_player(), and streaming().

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uint32 FAT_getNumberedSong	(	char	songNumber,
		uint32	dir_lba
	)

GetNumberedSong.

Get the file number of a song given a 2 digit BCD of the first two digits of the filename. eg given CHAR2BCD(8) as an argument the function will find the first file in the current directory whos name begins with "08" and ends with ".mp3". Can be removed from code by setting FAT_NumberedSong_EN to 0.

Parameters: