suppose i have some data stored in a pendrive in known format,now i want to read that data, how can i do this? in which format data is read from pendrive? please give me a detail description about the data read mechanism of pendrive.
There are different protocol layers involved, not sure which you're referring to.
application layer (any)
file system layer (mostly FAT16/FAT32)
media structure layer (MBR + partitions)
USB mass storage device class
general USB protocol framework
USB physical layer (full speed/high speed)
at the application layer you can read and write the files as you wish... the common way is using fopen() fread() and fwrite() [also use fclose() ] depending the system and developing language....