mp.rar_dsPIC33FJ256GP710

#include "p33FJ256GP710.h" #include "glcd.h" #include "uart.h" #include "timer1.h" #include "sdcard.h" #include "fileio.h" #include "stdlib.h" #include "ctype.h" #include "string.h" #include "stddef.h" // globals char FError; // error mail box DISK* D; // mounting information for default storage device DISK * mount( void) { LBA psize; // number of sectors in partition LBA firsts; // LBA of first sector inside the first partition int i; unsigned char *buffer; // 0. init the I/Os initSD(); // 1. check if the card is in the slot // 2. initialize the card if ( initMedia()) { Lcd_printf57(0,1,"ERROR INITMEDIA"); return NULL; } // 3. allocate space for a DISK structure D = (DISK *) malloc(sizeof( DISK)); if ( D == NULL) // report an error { Lcd_printf57(0,1,"NOT ALLOCATE DISK"); return NULL; } // 4. allocate space for a temp sector buffer buffer = (unsigned char*) malloc(1024); if ( buffer == NULL) // report an error { Lcd_printf57(0,1,"NOT ALLOCATE BUFF"); free( D); return NULL; } // 5. get the Master Boot Record if ( !readSECTOR( FO_MBR, buffer)) { Lcd_printf57(0,1,"ERROR READ SECTOR"); free( D); free( buffer); return NULL; } // 6. check if the MBR sector is valid // verify the signature word if (( buffer[ FO_SIGN] != 0x55) || ( buffer[ FO_SIGN +1] != 0xAA)) { Lcd_printf57(0,1,"ERROR MBR"); free( D); free( buffer); return NULL; } // Valid Master Boot Record Loaded // 7. read the number of sectors in partition psize = ReadL( buffer, FO_FIRST_SIZE); // 8. check if the partition type is acceptable i = buffer[ FO_FIRST_TYPE]; switch ( i) { case 0x04: case 0x06: case 0x0E: // valid FAT16 options break; default: Lcd_printf57(0,1,"ERROR PARTI TYPE"); free( D); free( buffer); return NULL; } // switch // 9. get the first partition first sector -> Boot Record // get the 32 bit offset to the first partition firsts = ReadL( buffer, FO_FIRST_SECT); // assuming FO_MBR == 0 // 10. get the sector loaded (boot record) if ( !readSECTOR( firsts, buffer)) { Lcd_printf57(0,1,"ERROR BOOT SECTOR"); free( D); free( buffer); return NULL; } // 11. check if the boot record is valid // verify the signature word if (( buffer[ FO_SIGN] != 0x55) || ( buffer[ FO_SIGN +1] != 0xAA)) { free( D); free( buffer); return NULL; } // Valid Partition Boot Record Loaded // get the full partition/drive layout // 12. determine the size of a cluster D->sxc = buffer[ BR_SXC]; // this will also act as flag that the disk is mounted // 13. determine fat, root and data LBAs // FAT = first sector in partition (boot record) + reserved records D->fat = firsts + ReadW( buffer, BR_RES); D->fatsize = ReadW( buffer, BR_FAT_SIZE); D->fatcopy = buffer[ BR_FAT_CPY]; // 14. ROOT = FAT + (sectors per FAT * copies of FAT) D->root = D->fat + ( D->fatsize * D->fatcopy); // 15. MAX ROOT is the maximum number of entries in the root directory D->maxroot = ReadOddW( buffer, BR_MAX_ROOT) ; // 16. DATA = ROOT + (MAXIMUM ROOT *32 / 512) D->data = D->root + ( D->maxroot >> 4); // assuming maxroot % 16 == 0!!! // 17. max clusters in this partition = (tot sectors - sys sectors )/sxc D->maxcls = (psize - (D->data - firsts)) / D->sxc; // 18. free up the temporary buffer free( buffer); return D; } // mount //---------------------------------------------------------------------- // unmount initializes a DISK structure for FILEIO access // void unmount( void) { free( D); } // unmount //---------------------------------------------------------------------- // int readDIR( FILE *fp, unsigned e) // loads current entry sector in file buffer // returns FAIL/TRUE { LBA l; int r; // fp->buffer = t; // Lcd_printf(0,3,"THOAT2"); if(fp->buffer == NULL) Uart2_send_string("BUFF ERROR"); // load the root sector containing the DIR entry "e" l = fp->dsk->root + (e >> 4); // Write_int(0,3,l); r = readSECTOR( l, fp->buffer); return (r ); } // readDIR //---------------------------------------------------------------------- // unsigned writeDIR( FILE *fp, unsigned entry) // write current entry sector // returns FAIL/TRUE { int r; LBA l = fp->dsk->root + (entry >> 4); // fp->buffer = t; // write the root sector r = writeSECTOR( l, fp->buffer); return (r) ; } // writeDIR //---------------------------------------------------------------------- // Find a File entry in current directory // unsigned findDIR( FILE *fp) // fp file structure // return found/not_found/fail { unsigned eCount; // current entry counter unsigned e; // current entry offset in buffer int i, a; DISK *dsk = fp->dsk; // 1. start from the first entry eCount = 0; // load the first sector of root if ( !readDIR( fp, eCount)) { return FAIL; Uart2_send_string("N READ DIR"); } // Lcd_printf(0,2,"ERROR READ DIR"); // 2. loop until you reach the end or find the file while ( 1) { // 2.0 determine the offset in current buffer e = (eCount&0xf) * DIR_ESIZE; // 2.1 read the first char of the file name a = fp->buffer[ e + DIR_NAME]; // 2.2 terminate if it is empty (end of the list) if ( a == DIR_EMPTY) { return NOT_FOUND; } // empty entry // 2.3 skip erased entries if looking for a match if ( a != DIR_DEL) { // 2.3.1 if not VOLume or DIR compare the names a = fp->buffer[ e + DIR_ATTRIB]; if ( !((a & ATT_DIR) || ( a & ATT_VOL)) ) { // compare file name and extension for (i=DIR_NAME; i<DIR_ATTRIB; i++) { if ( ( fp->buffer[ e + i]) != ( fp->name[i])) break; // difference found } if ( i == DIR_ATTRIB) { // entry found, fill the file structure fp->entry = eCount; // store entry index fp->time = ReadW( fp->buffer, e + DIR_TIME); //Lcd_printf(0,7,"QUAA"); fp->date = ReadW( fp->buffer, e + DIR_DATE); fp->size = ReadL( fp->buffer, e + DIR_SIZE); fp->cluster = ReadL( fp->buffer, e + DIR_CLST); return FOUND; } // Lcd_printf(0,7,"READDIR F"); } // not dir nor vol } // not deleted // 2.4 get the next entry eCount++; if ( (eCount & 0xf) == 0) { // load a new sector from the Dir if ( !readDIR( fp, eCount)) { return FAIL; Uart2_send_string("READDIR FAIL"); } } // 2.5. exit the loop if reached the end or error if ( eCount >= dsk->maxroot) { return NOT_FOUND; // last entry reached Uart2_send_string("NOT FOUND DIR"); } }// while } // findDIR //-------------------------------------------------------------