Hi, Thanks to Mike's email, I've decided to compile few facts about storage devices and file operations (at least what I know): 1. Flash memory and hard disks work differently. Although they are both called storage devices, hard disks use disc platters coated with magnetic materials for storing data, as opposed to stored electrons and circuitry that is used on flash chips. 2. When information is gone from hard disks, there are ways of recovering it; however, due to electronic nature of them, once something is gone from flash, it is gone permanently. 3. Flash is more shock resistant than hard disks and take less power than HDD's. 4. It is generally more costly to produce flash chips than hard disks due to manufacturing process involved. Hard disks require disc platters and magnetic material on top which is readily available; however, due to circuitry and production of microcontrollers and memory cells, flash is somewhat more expensive. 5. Before a file is saved to any storage medium, the temporary content is stored on RAM (Random Access Memory, or physical memory). This has both advantages and drawbacks: that it is faster than flash memory when accessing data yet it is volatile - losing its contents when power is off. When the "save as" command is invoked, a "file write" operation is called to write newer content from RAM to the desired file. Also, when the "open" command is used, a "file read" operation is called - reading the contents of the file into RAM. Thus, in actuality, we are dealing with two copies of a single file when wordprocessor or similar programs are run - the actual file on the storage medium and a "temporary content" that is stored on RAM for us to operate on. It is hard for me to describe all the details of this even in psudo code, so I'll leave it up to the "BSP experts" like Mike and James A. to explain it further. 6. YOU CANNOT USE A STORAGE MEDIUM FORMATTED IN NTFS!!! Windows CE itself (not just the BSP's Task manager/add-on interface) does not like it. There is a "NTFS-like" file system, called exFAT a.k.a. FAT64 that is optimized for storage devices, but no WinCE nk.exe prior to 6.0 does not support it natively (so does Windows prior to WinVista Service Pack 1 and similar). At this time, the only supported file systems are FAT (or FAT16) and FAT32. Hope this helps. Sorry for some words... Cheers, Joseph P.S. Alex H., can you help me explain file i/o in more simpler terms...
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