Write and Read of SD Card

Types of data logger
1) just store the data on the card
2) Acquire the analogical signals and store it on the card (preferable)

Points
1)Format the card from windows with a known FAT, when you format Windows always prompt you the kind of FAT that you want use (FAT, FAT16, FAT32).
2)Filling the card with a binary file that contains the number FF or 00.
3)Know the exact location of the file start , communicate it to the PIC and start to write.