 Commodore 1571 floppy drive | |
| Manufacturer | Commodore Business Machines, Inc. |
|---|---|
| Type | Floppy drive |
| Release date | 1985 |
| Introductory price | US$300 (1985) equivalent to $800 in 2023 |
| Discontinued | 1993 |
| Media | 5¼" floppy disk DS DD using GCR or MFM[1] |
| Operating system | CBM DOS 3.0[1] (128D uses v3.1) |
| CPU | MOS 6502[2] @ 2 MHz, WD1770[3] |
| Memory | 2 kB RAM 32 kB ROM[2] |
| Storage | 350-410 kB (GCR and MFM)[2] |
| Connectivity | Commodore proprietary serial IEEE-488 5200 bytes/s[2] |
| Backward compatibility | Commodore 64, Commodore 128 |
| Predecessor | Commodore 1570 |
| Successor | Commodore 1581 |
The Commodore 1571 is Commodore's high-end 5¼" floppy disk drive, announced in the summer of 1985. With its double-sided drive mechanism, it has the ability to use double-sided, double-density (DS/DD) floppy disks, storing a total of 360 kB per floppy. It also implemented a "burst mode" that improved transfer speeds, helping address the very slow performance of previous Commodore drives.
Earlier Commodore drives used a custom group coded recording format that stored 170 kB per side of a disk. This made it fairly competitive in terms of storage, but limited it to only reading and writing disks from other Commodore machines. The 1571 was designed to partner with the new Commodore 128 (C128), which introduced support for CP/M. Adding double-density MFM encoding allowed the drive to read and write contemporary CP/M disks (and many others).
In contrast to its single-sided predecessors, the 1541 and the briefly-available 1570, the 1571 can use both sides of the disk at the same time. Previously, users could only use the second side by manually flipping them over. Because flipping the disk also reverses the direction of rotation, the two methods are not interchangeable; disks which had their back side created in a 1541 by flipping them over would have to be flipped in the 1571 too, and the back side of disks written in a 1571 using the native support for two-sided operation could not be read in a 1541.
- ^ a b Zimmerman, Bo (20 March 2015). "Commodore 1570/1571". zimmers.net. Archived from the original on 9 September 2023. Retrieved 11 September 2023.
- ^ a b c d "Commodore 1571 disk drive user's guide". Commodore Business Machines, Inc. August 1985. Retrieved 1 February 2024.
- ^ "Memory map". Commodore Business Machines, Inc. October 1986. Retrieved 27 April 2016.