1. A method for transferring data between a host device and an external device having a FAT32 (File Allocation Table) file system, the method comprising: accepting parameters for an incoming data file from the host device; allocating memory blocks for the incoming data file on the external device based on the parameters, wherein the allocated memory blocks are not initialized; creating a file footprint by indexing the allocated memory blocks in a memory index table; reading the memory index table to identify the file footprint; and receiving the incoming data file from the host device into the file footprint using a direct memory access (DMA) data transfer techniques, wherein the file footprint specifies the sector/cluster mappings for storing the data file on the external device.