hard-sector 5 1/4 disk

I can't name a machine that did, but I know some CP/M boxes used them. So that excludes Kaypro, ATR8000, ATR8500, SuperBrain, Morrow MDx, Osborne, Xerox 820-II, Commodore 128, and IBM PC. All run CP/M and none use hard sectored disks. I do know that lots of drive controllers use the index hole of soft-sectored disks to time the disk's rotation in order to determine which type drive is running on it. 92/180/320/720k disks rotate at 300rpm and 'high-density' drives like 77track 8' hd and your standard 1.44mb floppy drives rotate at 360rpm. Some drives by other makers run at odd speeds. Atari 8-bit drives generally run at 288rpm and this makes a difference esp when reading copy-protected disks. Regards, Jeff In <01102921415400.02413@ws1>, on 10/29/01 at 09:41 PM, Jim Donoghue &lt;jdonogh1(a)prodigy.net&gt; said: -- ----------------------------------------------------------- Jeffrey S. Worley Asheville, NC USA 828-6984887 UberTechnoid(a)Home.com -----------------------------------------------------------