File content as of revision 1:456047999cb0:

#include "mbed.h"
#include "SDFileSystem.h"
#define LEN 2048
SDFileSystem sd(PA_14, PA_13, PA_12, PA_11, "sd"); // the pinout on the mbed Cool Components workshop board  SDFileSystem sd(PB_03, PB_02, PB_01, PB_00, "sd");
//SDFileSystem sd(PB_03, PB_02, PB_01, PB_00, "sd");
Serial uart1(PA_13,PA_14);
FILE *fp;
char buf[LEN];
int main() {
    uart1.baud(9600);
    uart1.printf("SD Card FAT FileSystem Testing....\r\n");
 
    mkdir("/sd/mydir", 0777);
    
    if((fp = fopen("/sd/mydir/sdtest.txt", "w")) == NULL){
        error("Could not open file for write\r\n");
        return -1;
    }
    fprintf(fp, "DFRobot Test String ABCDEFG......\r\n");
    fclose(fp); 

    if((fp = fopen("/sd/mydir/sdtest.txt", "r")) == NULL){
        error("Could not open file for write\r\n");
        return -1;
    }
    memset(buf,0,LEN);
    fread(buf,LEN,1,fp);
    buf[LEN-1] = 0;
    fclose(fp);
    uart1.printf("------------read sdtest.txt-----------\r\n");
    uart1.printf("%s",buf);
    uart1.printf("------------end-----------\r\n");
}