MMC/SD card FAT16 interfacing!

sd card fat16

Hi all members!

Have a nice day!

Now, this's my free time. I'm studying MMC/SD card reader (micro). The read_sector() & write_sector() of MMC/SD card --->>> Correct!!!

My problem:
- fat_search_file() function not work correct !

code:
unsigned char fat_search_file (unsigned char *File_Name, unsigned int *Cluster, unsigned long *Size, unsigned char *Dir_Attrib, unsigned char *Buffer)
{
unsigned char a;
unsigned int Dir_Cluster_Store=0;

Dir_Cluster_Store = *Cluster;

for(a = 0;a < 100;a++)
{
*Cluster = fat_read_dir_ent(Dir_Cluster_Store,a,Size,Dir_Attrib,Buffer);
if (*Cluster == 0xffff)
{
return(0); //File not Found
}
if(strcmp((char*)File_Name, (char*)Buffer) == 0)
{
return(1); //File Found
}
}
return(2); //Error
}

please help me check it!

"myfat.h":


/*#######################################################################################
Connect ARM to MMC/SD

Copyright (C) 2004 Ulrich Radig
#######################################################################################*/

#ifndef _FAT_H_
#define _FAT_H_

//Prototypes
extern unsigned int fat_root_dir_addr (unsigned char *);
extern unsigned int fat_read_dir_ent (unsigned int,unsigned char,unsigned long*,unsigned char *,unsigned char *);
extern void fat_load (unsigned int,unsigned long *,unsigned char *);
extern void fat_read_file (unsigned int,unsigned char *,unsigned long);
extern void fat_write_file (unsigned int,unsigned char *,unsigned long);
extern void fat_init (void);
extern unsigned char fat_search_file (unsigned char *,unsigned int *,unsigned long *,unsigned char *,unsigned char *);

//Block Size in Bytes
//#define BlockSize 512

//Master Boot Record
#define MASTER_BOOT_RECORD 0

//Volume Boot Record location in Master Boot Record
#define VBR_ADDR 0x1C6

//define ASCII
#define SPACE 0x20
#define DIR_ENTRY_IS_FREE 0xE5
#define FIRST_LONG_ENTRY 0x01
#define SECOND_LONG_ENTRY 0x42

//define DIR_Attr
#define ATTR_LONG_NAME 0x0F
#define ATTR_READ_ONLY 0x01
#define ATTR_HIDDEN 0x02
#define ATTR_SYSTEM 0x04
#define ATTR_VOLUME_ID 0x08
#define ATTR_DIRECTORY 0x10
#define ATTR_ARCHIVE 0x20

// 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

// 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

struct BootSec
{
unsigned char BS_jmpBoot[3];
unsigned char BS_OEMName[8];
unsigned int BPB_BytesPerSec; //2 bytes, At record 11:12
unsigned char BPB_SecPerClus; // At record 13
unsigned int BPB_RsvdSecCnt; //2 bytes, At record 14:15
unsigned char BPB_NumFATs; // At record 16
unsigned int BPB_RootEntCnt; //2 bytes
unsigned int BPB_TotSec16; //2 bytes
unsigned char BPB_Media; //
unsigned int BPB_FATSz16; //2 bytes
unsigned int BPB_SecPerTrk; //2 bytes
unsigned int BPB_NumHeads; //2 bytes
unsigned long BPB_HiddSec; //4 bytes
unsigned long BPB_HugeSectors; //
unsigned long BPB_RootClust; // start cluster for root directory
unsigned long BPB_TotSec32; //4 bytes
};

struct partrecord // length 16 bytes
{
BYTE prIsActive; // 0x80 indicates active partition
BYTE prStartHead; // starting head for partition
WORD prStartCylSect; // starting cylinder and sector
BYTE prPartType; // partition type (see above)
BYTE prEndHead; // ending head for this partition
WORD prEndCylSect; // ending cylinder and sector
DWORD prStartLBA; // first LBA sector for this partition
DWORD prSize; // size of this partition (bytes or sectors ?)
};

struct partsector
{
char psPartCode[512-64-2]; // pad so struct is 512b
BYTE psPart[64]; // four partition records (64 bytes)
BYTE psBootSectSig0; // two signature bytes (2 bytes)
BYTE psBootSectSig1;
};

//FAT12 and FAT16 Structure Starting at Offset 36
#define BS_DRVNUM 36
#define BS_RESERVED1 37
#define BS_BOOTSIG 38
#define BS_VOLID 39
#define BS_VOLLAB 43
#define BS_FILSYSTYPE 54

//FAT32 Structure Starting at Offset 36
#define BPB_FATSZ32 36
#define BPB_EXTFLAGS 40
#define BPB_FSVER 42
#define BPB_ROOTCLUS 44
#define BPB_FSINFO 48
#define BPB_BKBOOTSEC 50
#define BPB_RESERVED 52

#define FAT32_BS_DRVNUM 64
#define FAT32_BS_RESERVED1 65
#define FAT32_BS_BOOTSIG 66
#define FAT32_BS_VOLID 67
#define FAT32_BS_VOLLAB 71
#define FAT32_BS_FILSYSTYPE 82
//End of Boot Sctor and BPB Structure

struct DirEntry {
unsigned char DIR_Name[11]; //8 chars filename
unsigned char DIR_Attr; //file attributes RSHA, Longname, Drive Label, Directory
unsigned char DIR_NTRes; //set to zero
unsigned char DIR_CrtTimeTenth; //creation time part in milliseconds
unsigned int DIR_CrtTime; //creation time
unsigned int DIR_CrtDate; //creation date
unsigned int DIR_LastAccDate; //last access date
unsigned int DIR_FstClusHI; //first cluster high word
unsigned int DIR_WrtTime; //last write time
unsigned int DIR_WrtDate; //last write date
unsigned int DIR_FstClusLO; //first cluster low word
unsigned long DIR_FileSize;
};

#endif //_FAT_H_

fat16 structure

Nobody help me!!!!

sd card fat 16

why nobody help me??? :?:

mmc dir_filesize

I can help you provided you provide whole code.
I am not getting anything with these snippets.