USB RFI

RFI (Reliable File Interface) is provided as an alternative to USB mass storage under Windows.

Mass storage is a very clean solution when connecting a USB drive to a PC. However, when the embedded target is complex, this solution has certain limitations:

Windows writes directly to the target drive; there is no way to synchronize access between the PC and the embedded application. This means that either the PC or the embedded target, but not both, can access the drive at the same time.
Windows generally requires that you use their FAT file system; unfortunately, FAT is not adequately reliable for embedded designs.

RFI resolves these problems by providing a more NFS-like access to the embedded system, so that the embedded system always remains in control of the storage media. Access on the embedded side is through a standard API, so the PC over USB appears simply as another task accessing the file system on the target. In this way any combination of file system types can be used on the embedded target.

RFI is provided as a Windows file system driver. It communicates with the USB device using HCC's USB Embedded Pipe driver.

RFI’s look and feel are exactly like a standard flash driver in Windows Explorer; it is only the underlying technology that is changed in this solution. With RFI, the developer has more choices and more flexibility, and the products that use RFI are significantly more robust.