List of floppy disk formats
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Template:Short description Script error: No such module "For". Template:Use mdy dates
This is a list of different floppy disk formats.
Physical formats
| Size | Density | Sides | Tracks | tpi | bpi | Sectoring | Coercivity | Unformatted capacity per side |
|---|---|---|---|---|---|---|---|---|
| 2 inch Video Floppy | 52 | 256 | >800 kB or 50 fields of analog video[1] | |||||
| 2 inch LT-1 | Double | 80 | 245 | |||||
| 2<templatestyles src="Fraction/styles.css" />1⁄2 inch | Single | 16[2][3] | 48[2] | 64 kB | ||||
| 3 inch QuickDisk | ||||||||
| 3.25 inch | Single | 1 | 80[4] | 140 | 4,625 | 250 kB | ||
| Double | 9,250 | 500 kB | ||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Single | 2 | 40[5] | 67.5 | 8,650 | Soft | 665 Oe | 250 kBScript error: No such module "Unsubst". |
| Double | 80 | 135 | 8,717 | 665 Oe[6] | 500 kBScript error: No such module "Unsubst". | |||
| High | 80 | 135 | 17,434 | 720-750 Oe | 1 MB | |||
| Extended | 80 | 135 | 34,868 | 900 Oe | 2 MB | |||
| Triple[7] | 240[8] | 406.5[8] | 36,700[8] | 6.5 MB | ||||
| 4 inch DemiDiskette | 1[9] | |||||||
| 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Single/Double | 2 | 40 | 48 | 5,876 | Soft or hard | 300 Oe | 250 kB |
| Quad | 77 | 100 | 300 Oe | 500 kB (Micropolis-compatible) | ||||
| Quad | 80 | 96 | 5,922 | 300 Oe | 500 kB | |||
| High | 80 | 96 | 9,646 | Soft | 600 Oe | 833 kB | ||
| EH[10] | 104 | 125 | 29,560 | 6.5 MB[11] | ||||
| 5<templatestyles src="Fraction/styles.css" />1⁄4 inch
Apple FileWare |
Double | 2 | 80 | 62.5 | Soft | 851 kiB[12] | ||
| 8 inch | Single | 77 | 48 | 3,268-3,408 | Soft or hard (inner edge) | 300 Oe | 1 MB | |
| Double | 6,816 | 1 MB | ||||||
| HD[13] | 154 | 96 | 20,560 | 600 Oe | 9.6 MB[14] | |||
| 8 inch Memorex FD | 650 | 1[15] | 50[15] | 2,400 | Hard (outer edge) | 1.5 Mb[15] | ||
| 651 | 64[16] | 3,100 | 2.5 Mb[16][17] | |||||
| 8 inch Burroughs | Double | 2 | 139 | 150 | 7,100 | 2[18] |
Logical formats
Throughout the 1970s and 1980s, many different logical disk formats were used, depending on the hardware platform.
| Platform | Size | Density | Sides | Tracks/ side | Sectors/ track | Bytes/ sector | Sectoring | Capacity | rpm | Encoding | Note |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Acorn | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Single | 1 | 40 | 10 | 256 | Soft | 100 kB | 300 | FM | |
| 80 | 200 kB | ||||||||||
| Double | 1 | 40 | 16 | 256 | 160 kB | MFM | |||||
| 80 | 320 kB | ||||||||||
| 2 | 640 kB | ||||||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 2 | 80 | 16 | 256 | 640 kB | 300 | MFM | Format L: MOS (Electron, Master Compact) | ||
| 5 | 1024 | 800 kB | Template:Ubl | ||||||||
| High | 10 | 1,600 kB | Format F: RISC OS 3 and later. Archimedes models before the A5000 require an upgraded floppy drive. | ||||||||
| Agat | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 2 | 80 | 21 | 256 | 840 kB | 300 | MFM | [NB 1] | |
| Amstrad CPC/PCW | 3 inch | Double | 1 | 40 | 9 | 512 | 180 kB | 300 | MFM | Single head drive, but double-sided floppy discs (total of 360 kB per floppy) | |
| Amstrad PCW8512/9512 | 3 inch | Double | 2 | 80 | 9 | 512 | 720 kB | 300 | MFM | 720 kB mode uses both sides - ensure disc inserted correct way up. | |
| Apple II | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 1 | 35 | 13 | 256 | Soft | 113.75 kB | 300 | GCR | [NB 2] |
| 1 | 16 | 140 kB | |||||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 1 | 80 | Variable (8-12) | 512 | 400 kB | 394 - 590 | GCR | [NB 3] | ||
| 2 | 800 kB | ||||||||||
| High | 2 | 80 | 18 | 512 | 1,440 kB | 300 | MFM | [NB 4] | |||
| Apple Lisa | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch FileWare | Double | 2 | 46 | Variable (15-22) | 512 | Soft | 851 kB | 218 - 320[19] | GCR | |
| Apple Lisa 2/Macintosh XL,
Macintosh |
3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 1 | 80 | Variable (8-12) | 512 | Soft | 400 kB | 394 - 590 | GCR | |
| Apple Macintosh | 2 | 800 kB | |||||||||
| High | 2 | 80 | 18 | 512 | 1,440 kB | 300 | MFM | ||||
| Atari 8-bit | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Single | 1 | 40 | 18 | 128 | Soft | 90 kB | 288 | FM | [NB 5] |
| Dual | 26 | 128 | 130 kB | MFM | |||||||
| Double | 18 | 256 | 180 kB | ||||||||
| Double | 2 | 18 | 256 | 360 kB | 300 | ||||||
| Atari ST/TT/Falcon | 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 1 | 80 | 9 | 512 | Soft | 360 kB | 300 | MFM | |
| 2 | 720 kB | ||||||||||
| High | 18 | 1,440 kB | |||||||||
| Coleco ADAM | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 1 | 40 | 8 | 512 | soft | 160 kB | 300 | MFM | |
| Commodore 64 (8-bit) | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 1 | 35 | Variable (17-21) ZCAV | 256 | Soft | 170 kB | 300 | GCR | [NB 6] |
| 2 | 340 kB | ||||||||||
| Quad | 1 | 77 | Variable (23-29) ZCAV | 521 kB | |||||||
| 2 | 1,042 kB | ||||||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 2 | 80 | 10 | 512 | 800 kB | MFM | ||||
| Commodore Amiga | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 2 | 40 | 11 | 512 | Soft | 440 kB[NB 7] | 300 | MFM | [NB 8] |
| Quad | 80 | 880 kB[NB 9] | |||||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 880 kB | |||||||||
| High | 19 | 1,520 kB | GCR | [NB 10] | |||||||
| 22 | 1,760 kB | 150 | MFM | [NB 8] | |||||||
| Commodore 900 | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | High | 2 | 80 | 13-16 | 512 | Soft | 1,200kB | ? | GCR | https://vintagecomputer.ca/files/Commodore/C900/C900%20Floppy%20Specification.pdf |
| IBM 33FD | 8 inch | Single | 1 | 77 | 26 | 128 | 240.5 kiB | 360 | FM | Diskette 1[20] | |
| 15 | 256 | 277.5 kiB | |||||||||
| 8 | 512 | 296 kiB | |||||||||
| IBM 43FD | 2 | 26 | 128 | 481 kiB | Diskette 2[20] | ||||||
| 15 | 256 | 555 kiB | |||||||||
| IBM 53FD | Double | 26 | 256 | 962 kiB | MFM | Diskette 2D[20] | |||||
| 15 | 512 | 1.08 MiB | |||||||||
| 8 | 1,024 | 1.16 MiB | |||||||||
| DEC RX01 | 8 inch | Single | 1 | 77 | 26 | 128 | 250 kB | 360 | FM | ||
| DEC RX02 | 8 inch | Double | 1 | 77 | 26 | 256 | 500 kB | 360 | FM/MFM | ||
| DEC RX50 | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Quad | 1 | 80 | 10 | 512 | 400 kB | 300 | MFM | ||
| IBM PC compatibles[21] | 8 inch | Single | 1 | 77 | 26 | 128 | Soft | 250.25 kB[NB 11][21][22][23] | 360 | FM | [NB 12] |
| 2 | 500.5 kB[NB 11][21][22][23] | ||||||||||
| Double | 1 | 8 | 1,024 | 616 kB[NB 11][22][23] | MFM | ||||||
| 2 | 1,232 kB[NB 11][21][22][23] | ||||||||||
| 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 1 | 40 | 8 | 512 | 160 kB[NB 11] | 300 | MFM | |||
| 2 | 320 kB[NB 11] | ||||||||||
| 1 | 9 | 180 kB[NB 11] | |||||||||
| 2 | 360 kB[NB 11] | ||||||||||
| Quad[NB 13] | 1 | 80 | 8 | 320 kB[NB 11] | 300 | ||||||
| 2 | 640 kB[NB 11] | ||||||||||
| High | 2 | 80 | 15 | 1,200 kB[NB 11] | 360 | ||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 1 | 80 | 8 | 512 | 320 kB[NB 11] | 300 | MFM | |||
| 9 | 360 kB[NB 11] | ||||||||||
| 2 | 8 | 640 kB[NB 11] | |||||||||
| 9 | 720 kB[NB 11] | ||||||||||
| High | 18 | 1,440 kB[NB 11] | |||||||||
| 21 | 1,680 kB[NB 11] | DMF[NB 14] | |||||||||
| 82 | 1,720 kB[NB 11] | ||||||||||
| Extended | 80 | 36 | 2,880 kB[NB 11] | ||||||||
| MGT SAM Coupé | 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 2 | 80 | 10 | 512 | 800 kB | 300 | MFM | ||
| NEC PC98 | 8 inch | Single | 1 | 77 | 26 | 128 | 250.25 kB[NB 11] | 360 | FM | ||
| Double | 2 | 77 | 8 | 1,024 | 1,232 kB[NB 11] | MFM | |||||
| 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 2 | 80 | 8 | 512 | 640 kB[NB 11] | 360 | MFM | |||
| 9 | 720 kB[NB 11] | ||||||||||
| High | 15 | 1,200 kB[NB 11] | |||||||||
| 77 (80)[NB 15] | 8 | 1,024 | 1,232 (1,280) kB[NB 11][NB 15] | [NB 15] | |||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 2 | 80 | 8 | 512 | 640 kB[NB 11] | 360 | MFM | |||
| 9 | 720 kB[NB 11] | ||||||||||
| High | 15 | 1,200 kB[NB 11] | 3-mode[NB 16][NB 15] | ||||||||
| 77 (80)[NB 15] | 8 | 1,024 | 1,232 (1,280) kB[NB 11][NB 15] | ||||||||
| 80 | 18 | 512 | 1.44 MB[NB 11] | 300 | |||||||
| Triple | 240 | 38 | 512 | 9,120 kB | 360 | NEC PC-88 VA3 2TD drive only[8][7] | |||||
| Osborne 1[24] | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Single | 1 | 40 | 10 | 256 | Soft | 100 kB | 300 | FM | |
| Double | 5 | 1,024 | 200 kB | MFM | |||||||
| Sega SF-7000 | 3 inch | Single | 2 | 40 | 16 | 256 | 160 kB | ? | ? | Expansion unit for SC-3000 home computer. Capacity is per side. | |
| SHARP X68000 | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | High | 2 | 77 | 8 | 1,024 | 1,232 kB[NB 11] | 360 | MFM | ||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | |||||||||||
| SHARP CE-1600F, CE-140F | 2<templatestyles src="Fraction/styles.css" />1⁄2 inch[2][3] | Single | drive: 1, diskette: 2 (flippable) | 16 | 8 | 512 | 2× 64 kB | 270 | GCR (4/5) | Internally based on FDU-250 Micro Floppy Disk Drive Unit[2] | |
| Thomson | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Single | 1 | 40 | 16 | 128 | 80 kB | 300 | FM | Thomson UD90.070 | |
| Double | 2 | 256 | 320 kB | MFM | Thomson DD90-320[NB 17] | ||||||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 1 | 80 | 16 | 256 | 320 kB | 300 | MFM | Thomson TO9, Thomson DD09-350 | ||
| Double | 2 | 640 kB | Thomson TO8D, TO9+, Thomson DD90-352[NB 18] | ||||||||
| Victor 9000 / ACT Sirius 1[26] | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Single | 1 | 80 | 11-19 (variable) | 512 | 612 kB[27] | 252-417 (variable) | GCR | Disks varied sectors/track and disk speed to keep consistent bit density across tracks[26] | |
| Double | 2 | 512 | 1,196 kB[27] | ||||||||
| Tandy TRS-80 | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Single | 1 | 35 | 10 | 256 | Soft | 88 kB | 300 | FM | Model 1/3/4 |
| 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 1 | 40 | 18 | 256 | 180 kB | MFM | Model 1/3/4P | |||
| 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 2 | 40 | 18 | 256 | 360 kB | MFM | Model 4D | |||
| 8 inch | Double | 1 | 77 | 26 | 256 | 500 kB | MFM | Model 2 | |||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Single | 1 | 40 | 2 | 1,280 | 100 kB[28] | FM | Tandy Portable Disk Drive (aka Brother FB-100, knitking FD-19) | |||
| 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Single | 1 | 80 | 2 | 1,280 | 200 kB[29] | FM | Used only in Tandy Portable Disk Drive 2 | |||
| 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 1 | 35 | 18 | 256 | 157 kB[30] | MFM | Color Computer | |||
| HP 9114A | 3<templatestyles src="Fraction/styles.css" />1⁄2 inch | Double | 2 | 80 | 16 | 256 | 128-710kB[31] | 600 | MFM | Used with HP 110 and Portable Series 40 & 70 | |
| HP 9895A | 8 inch | Double | 2 | 77 | 29 | 256 | 1.18 MB[32] | 360 | MFM | ||
| HP 9130K | 5<templatestyles src="Fraction/styles.css" />1⁄4 inch | Double | 2 | 35 | 16 | 256 | 286 kB[33] | 300 | MFM | ||
| Burroughs MD122 | 8 inch | Double | 2 | 139 | 44 | 256 | Soft | 6.26 MB[18] | 524 | MFM | |
| Memorex 650 | 8 inch | Single | 1 | 50 | 8 | 3,500 b | Hard | 1.4 Mb[15] | 375 | FM | |
| Memorex 651 | Single | 64 | 32 | 1.056 b | 2.2 Mb[17] |
| Platform | Size | Density | Side | Track | Sector | Byte | Sectoring | Capacity | RPM | Encoding | Note |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Commodore 128 (CP/M) | 5 1/4 | Double | 2 | 40 | 26 | 128 | Soft | 260K | 300 | MFM | Commodore 1571 |
| 16 | 256 | 320K | |||||||||
| 9 | 512 | 360K | |||||||||
| 5 | 1,024 | 400K |
https://www.c64-wiki.com/wiki/Commodore_1571
https://vintagecomputer.ca/files/Commodore/C900/C900%20Floppy%20Specification.pdf
See also
- Zip drive (floppy-like, but incompatible medium using different technology)
- PocketZip (floppy-like, but incompatible medium using different technology)
- SuperDisk (floppy-like with drives also compatible with 3.5" floppy disks)
- Magneto-optical drive (floppy-like, but incompatible medium using different technology)
Notes
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- ↑ Custom controller with unique track layout.[1]
- ↑ 16 sector filesystems require a compatible disk controller (PROM update) and Apple DOS 3.3 or later.
- ↑ Apple II double-density 3<templatestyles src="Fraction/styles.css" />1⁄2-inch (90 mm) drives use variable sectors sizes (tracks 00-15: 12 sectors, tracks 16-31: 11 sectors, tracks 32-47: 10 sectors, tracks 48-63: 9 sectors, tracks 64-79: 8 sectors), 394 rpm to 590 rpm. [2]
- ↑ Apple II high-density 3<templatestyles src="Fraction/styles.css" />1⁄2-inch (90 mm) drives require a compatible disk controller and ProDOS 8.
- ↑ Third party drives offer up to 1440 KB.
- ↑ Commodore floppy drives used a fixed rotation speed with variable sector density (see: Zone bit recording).
- ↑ This format was used by the Amiga 1020 external floppy drive and some third-party drives connected to the normal Amiga floppy drive bus.
- ↑ a b Though the Amiga used MFM, the format places sectors too close together for a standard IBM PC compatible floppy disk controller to read (appearing as one 5632-byte physical sector per track).
- ↑ Format used by rare third-party drives with quad density disks; such drives were usually switchable between 80-track and 40-track (A1520/PC-compatible) operation.
- ↑ Format used by third-party gcrdisk.device driver in order to use PC-standard HD floppy drives (which rotated at a fixed 300 rpm) via the Amiga floppy drive bus. The Amiga's floppy controller could not keep up with the data rate needed for MFM recording on HD floppies without reducing rotational speed, so the third party driver used an alternate GCR mode.
- ↑ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae The calculated formatted capacity is based on FAT12 format.
- ↑ While IBM didn't include an 8-inch floppy drive option on any of their PCs and PC DOS, MS-DOS 1.25 supported 8-inch disks and added support for higher capacities in version 2.0. MS-DOS' predecessor 86-DOS used 8-inch diskettes as well.
- ↑ Rare format appearing on some early PC/XT clones using quad-density disks.
- ↑ These variations are known as DMF diskettes, used for a time to pack more data on to each disk for software distribution.
- ↑ a b c d e f Inner 3 tracks of 8 sectors/track format are unused.
- ↑ The PC98 3<templatestyles src="Fraction/styles.css" />1⁄2-inch (90 mm) formats are also known as "3 Mode" floppy disks, usable on IBM PC compatibles with a 3-mode floppy drive.
- ↑ The two sides are managed as two independent 160 KB disks
- ↑ The two sides are managed as two independent 320 KB disks
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References
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- ↑ <templatestyles src="Citation/styles.css"/>Template:Citation/make link, Kutaragi, Ken, "Magnetic disc reproducing apparatus", issued Script error: No such module "auto date formatter"., assigned to Sony CorporationScript error: No such module "Check for unknown parameters".
- ↑ a b c d Script error: No such module "citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
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- ↑ Script error: No such module "citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ a b c d Script error: No such module "citation/CS1".
- ↑ <templatestyles src="Citation/styles.css"/>Template:Citation/make link, Beck, John L.; Bornhorst, Randy J. & Smith, Donald J. et al., "Magnetic recording disk cartridge", issued Script error: No such module "auto date formatter".Script error: No such module "Check for unknown parameters".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ a b c d Script error: No such module "citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ a b c Script error: No such module "citation/CS1".
- ↑ a b c d Script error: No such module "citation/CS1".
- ↑ a b c d Script error: No such module "citation/CS1". (xix+1570 pages; 26 cm) (NB. This edition was published in 1988 after extensive rework of the withdrawn 1986 first edition by a different team of authors. [3])
- ↑ a b c d Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
Script error: No such module "Check for unknown parameters".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
External links
- Template:Sister-inline
- Floppy Disk Formats at the Museum of Obsolete Media