The Commodore 1541 (also known as the CBM 1541 and VIC-1541) is a floppy disk drive (FDD) which was made by Commodore International for the Commodore 64 (C64), Commodore's most popular home computer. The best-known FDD for the C64, the 1541 was a single-sided 170 kilobyte drive for 5ΒΌ" disks. The 1541 followed the previous Commodore 1540 (meant for the VIC-20).
The disk drive used Group Code Recording (GCR) and contained a MOS Technology 6502 microprocessor, doubling as a disk controller and on-board disk operating system processor. The number of sectors per track varied from 17 to 21 (an early implementation of Zone Bit Recording). The drive's built-in disk operating system was CBM DOS 2.6.
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