FAT File Systems - USB Mass Storage: Designing and Programming Devices and Embedded Hosts - page 187

Table 8-6: The data-cluster size varies with the file system and storage capacity.
(Source: Windows XP Professional Resource Kit)
Volume Size FAT16 Cluster Size FAT32 Cluster Size

16 MB-32 MB 512 bytes Not supported

33 MB-64 MB 1 KB 512 bytes

65 MB-128 MB 2 KB 1 KB

129 MB-256 MB 4 KB 2 KB

257 MB-512 MB 8 KB 4 KB

513 MB-1024 MB 16 KB 4 KB

1025 MB-2 GB 32 KB 4 KB

2 GB-4 GB

64 KB 1

4 KB

4 GB-8 GB Not supported 4 KB

8 GB-16 GB Not supported 8 KB

16 GB-32 GB Not supported 16 KB

1 Not supported by all FAT16 file systems.

cate with the chip using an asynchronous serial interface, SPI, or an I 2 C bus.
The chip also supports MultiMediaCard and SD-Card communications.
The chip responds to text commands. File commands enable opening, clos-
ing, reading, writing to, and deleting a file. Directory commands enable cre-
ating, changing, listing, and erasing a directory. Also supported are
commands for reading and writing directly to sectors in the storage media.
The chip requires +3.3V and +1.8V power supplies.
The uALFAT-SD development board includes a MultiMediaCard/SD-Card
connector and a regulator to convert 3.3V to 1.8V. A quick way to experi-
ment with the board is to insert a a MultiMediaCard or SD Card, connect
the board to a PC, and use a terminal program such as Windows' Hyperter-
minal to send commands and receive responses.
To connect to a PC, connect the board's asynchronous serial pins to the cor-
responding pins on a Maxim MAX3232 or similar RS-232 transceiver. If
your PC doesn't have an RS-232 port, connect the transceiver's RS-232 pins
to corresponding signals on an RS-232/USB converter. Or use an FTDI
Chip USB UART to interface the uAFLAT with a PC's USB port.