Commodore 1581

High Quality Content by WIKIPEDIA articles! The Commodore 1581 is a 31/2 inch double sided double density floppy disk drive made by Commodore Business Machines (CBM) primarily for its C64 and C128 home/personal computers. The drive stores 800 kilobytes using an MFM encoding but format different from both MS-DOS (720 kB), and the Amiga (880 kB) formats. With special software it's possible to read C1581 disks on a x86 PC system. And read MS-DOS disks in the C1581 (Big blue reader) provided the PC floppy handles the 720 kB size format. It was released in the summer of 1987 and quickly became popular with bulletin board system (BBS) operators and other users.