Christian,

I would ask; is this a G-job "one of a kind" or a product design? I'm guessing it's not a product so you have some alternatives.

Although Floppy Controllers are not in current production they are available and easy to use. Currently, National (and others) makes super i/o chips that include disk controllers and other PC i/o stuff.

Doing it natively with an 8051 requires serialization in(read) out(write), CRC validation and generation, and a few control lines buffered to be open collector which control direction, step, write gate, etc.

It is do-able (if the serialization is done in hardware) with a std 8051@11.059MHz but you would have to write tight code. Key would be having buffer space to "pre-assemble" each sector for write (including CRC) and to store for CRC checking on read.

You would probably take 3-5 rotations to read a full track unless you have enough buffer to read a full track. You also have to be careful about inter-sector "splices" which result from individual sector writes.

After doing all this you have FAT12 to deal with if you are trading disks with a PC. It's not hard at all but will take more buffer space.

If you are interested, look up Steve Wozniak's 5 IC 'APPLE II' disk controller not PC compatible but an example of what can be done.

regards,
p