Thanks again, Dave!

Observations about the floppy interface in NT/2K/XP are accurate. The native floppy driver is hard-wired to expect Microsoft-format floppies, even to having the boot sector information being critical. (Try clobbering a boot sector and then reading an otherwise valid diskette--you'll get a general failure). Sydex has quietly made a tidy side business of licensing a kernel mode floppy driver for NT and 2K/XP (in addittion to Win9x VxDs) to firms needing CP/M (using a DLL interface) or other direct access (driver access) to "alien" diskette types. We're currently working on a Vista driver. Operations like "sync to the index hole and read a bunch of IDs nonstop" are atomic functions with the driver. While this will keep most of our customers happy for the short term, I expect that floppy-less Windows PCs will shortly become the rule. We're actively investigating the possibility of a USB add-on floppy drive that will be able to handle most formats. I also anticipate that FDC chips will become rare birds, so implementation of some sort of FDC through software of FPGA would seem to be the wise course. I've investigated downloading special firmware into floppy USB chips, such as that used on the Teac FD-05U, but Teac has not been forthcoming on the controller chip details being used in any particular model.