Commodore 1581The Commodore 1581 is a 3.5 inch disk drive for the Commodore 64 and Commodore 128. The drive stores 800 kilobytes using an MFM format which is different from both MS-DOS 720 kb, and the Amiga 880 kb formats.
The 1581 supports a poor imitation of directories which are really just partitions and largely unused. It also supports burst loading like the Commodore 1571, but is actually faster as it is better designed. It has 3160 blocks free when formatted.
The 1581 is the highest density C64 serial bus drive made by Commodore. However Creative Micro Designs (CMD) makes the FD2000 (1.6MB) and (until recently) the FD4000 (3.2MB) 3.5" disk drives.
Based on material from FOLDOC, used with permission.