Reusing old floppy *drives*

Ordinary "PC" 3.5" drives don't change speed, but Amiga high-density drives do - they spin at 150 RPM when high-density media are inserted, maintaining the double-density data rate. This is because it was judged more economical to make a custom drive than to design a new Paula chip (for those that don't know, unlike in a PC, with the Amiga, there is no single "floppy controller" per se - the necessary functions are performed by a combination of CIA I/O pins, a massive shift register in the Paula chip and logical miniterms applied by Agnes to decode/encode the data to/from MFM). One advantage of changing the drive vs changing the chip is that any Amiga can take an HD drive, not just new models (the HD drive came in around the same time as the A3000, IIRC). The official drive may be the Chinon FZ-357A, but I am not in the room with an Amiga to verify that. It's unlikely to run across one of these drives outside of an Amiga context, but they did exist (and I do have a couple of them - they even work under emulators like A-Max and Shapeshifter to read high-density (FDHD) Mac disks).