Micropolis (company)

Micropolis Corporation (styled as MICROPΩLIS) was a disk drive company located in Chatsworth, California and founded in 1976. Micropolis initially manufactured high capacity (for the time) hard-sectored 5.25-inch floppy drives and controllers, later manufacturing hard drives using SCSI and ESDI interfaces.

Micropolis's first advance was to take the existing 48 tpi (tracks per inch) standard created by Shugart Associates, and double both the track density and track recording density to get four times the total storage on a 5.25-inch floppy in the "MetaFloppy" series with quad density (Drives :1054, :1053, and :1043) around 1980. Micropolis pioneered 100 tpi density because of the attraction of an exact 100 tracks to the inch. "Micropolis-compatible" 5.25-inch 77-track diskette drives were also manufactured by Tandon (TM100-3M and TM100-4M). Such drives were used in a number of computers like in a Vector Graphic S-100 bus computer, the Durango F-85 and in a few Commodore disk drives (8050, 8250, 8250LP and SFD-1001).

Micropolis later switched to 96 tpi when Shugart went to the 96 tpi standard, based on exact doubling of the 48 tpi standard. This allowed for backwards compatibility for reading by double stepping to read 48 tpi disks.

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