Compact Flash
Memory Card Recovery - Compact Flash
CompactFlash (CF) is a popular mass storage device format used in portable electronic devices such as digital cameras. The format was first specified and produced by SanDisk in 1994. CompactFlash was originally built around Intel’s NOR-based flash memory, but later it was switched over to NAND.
CompactFlash uses flash memory in a standardized enclosure. Flash memory can take only a limited number of erase/write cycles to a particular “block”. To prevent premature wear out of a sector, the controller in a CompactFlash device chooses the location for a piece of data at write time so as to spread out the writing over the device. This process is called wear leveling.
When used as a hard drive replacement in ATA mode, wear leveling becomes more important. The advanced CompactFlash controllers spread the wear leveling across the entire drive, thus allowing all blocks to participate in the write process. There are more advanced CompactFlash controllers that will also move the data that is rarely changed so that all blocks are worn evenly.
Types of CF Cards
There are two types of CF cards: Type I and Type II. Type I cards are 3.3 mm thick whereas type II cards are 5 mm thick. The cards are also categorized based on their speeds. Accordingly there are original CF, CF High Speed (using CF+/CF2.0), a faster CF 3.0 standard and a yet faster CF 4.0 standard.
