>While we're on the topic what are valid alternatives? Particularly
>ones suited to impelementing the mass storage USB device class.

Someone already given you a link to Cypress, but I don't know what their
mass storage line is like. However I have recently seen adverts for TI
series USB devices that include one for ATA devices. This particular device
is still an advance announcement with no data sheet.

Another alternative might be to roll your own by looking at the VHDL cores
at opencores.org where they have both USB 1.1 and 2 cores available for
using in FPGA's.

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