Known Disk Logical Formats
Throughout the 1970s and 1980s, many different logical disk formats were used, depending on the hardware platform.
Platform | Size | Density | Bytes/ sector | Sectors/ track | Tracks/ side | Sides | Capacity | RPM | Encoding | Note |
---|---|---|---|---|---|---|---|---|---|---|
IBM (3740 format) | 8 in | single | 128 | 26 | 74 | 1 | 250.25 KB | 360 | FM | |
Acorn | 5¼ in | single | 256 | 10 | 40 | 1 | 100 KB | 300 | FM | |
80 | 200 KB | |||||||||
double | 256 | 16 | 40 | 1 | 160 KB | MFM | ||||
80 | 320 KB | |||||||||
2 | 640 KB | |||||||||
3½ in (90 mm) | double | 256 | 16 | 80 | 2 | 640 KB | 300 | MFM | ||
1024 | 5 | 800 KB | ||||||||
high | 10 | 1600 KB | ||||||||
Apple II | 5¼ in | double | 256 | 13 | 35 | 1 | 113.75 KB | 300 | GCR | |
2 | 227.50 KB | |||||||||
16 | 1 | 140 KB | ||||||||
2 | 280 KB | |||||||||
3½ in (90 mm) | double | 512 | Variable (8-12) | 80 | 1 | 400 KB | CLV | GCR | ||
2 | 800 KB | |||||||||
high | 512 | 18 | 80 | 2 | 1440 KB | 300 | MFM | |||
Apple Macintosh | 3½ in (90 mm) | double | 512 | Variable (8-12) | 80 | 1 | 400 KB | CLV | GCR | |
2 | 800 KB | |||||||||
high | 512 | 18 | 80 | 2 | 1440 KB | 300 | MFM | |||
Atari 8-bit | 5¼ in | single | 128 | 18 | 40 | 1 | 90 KB | 288 | FM | |
enhanced | 128 | 26 | 127 KB | MFM | ||||||
double | 256 | 18 | 180 KB | |||||||
Commodore (8-bit) | 5¼ in | double | 256 | Variable (17-21) ZCAV | 35 | 1 | 170 KB | 300 | GCR | |
2 | 340 KB | |||||||||
quad | Variable (23-29) ZCAV | 77 | 1 | 521 KB | ||||||
2 | 1042 KB | |||||||||
3½ in (90 mm) | double | 512 | 10 | 80 | 2 | 800 KB | MFM | |||
Commodore Amiga | 3½ in (90 mm) | double | 512 | 11 | 80 | 2 | 880 KB | 300 | MFM | |
high | 22 | 1760 KB | 150 | |||||||
IBM PC compatibles | 8 in | single | 128 | 26 | 77 | 1 | 250.25 KB | 360 | MFM | |
2 | 500.5 KB | |||||||||
double | 1024 | 8 | 1 | 616 KB | ||||||
2 | 1232 KB | |||||||||
5¼ in | double | 512 | 8 | 40 | 1 | 160 KB | 300 | MFM | ||
2 | 320 KB | |||||||||
9 | 1 | 180 KB | ||||||||
2 | 360 KB | |||||||||
unknown | 8 | 80 | 1 | 320 KB | unknown | |||||
2 | 640 KB | |||||||||
high | 15 | 80 | 2 | 1200 KB | 360 | |||||
3½ in (90 mm) | double | 512 | 8 | 80 | 1 | 320 KB | 300 | MFM | ||
2 | 640 KB | |||||||||
9 | 720 KB | |||||||||
high | 18 | 80 | 1440 KB | |||||||
21 | 80 | 1680 KB | DMF | |||||||
82 | 1720 KB | |||||||||
extended | 36 | 80 | 2880 KB | |||||||
NEC PC98 | 8 in | single | 128 | 26 | 77 | 1 | 250.25 KB | 360 | FM | |
double | 1024 | 8 | 77 | 2 | 1232 KB | MFM | ||||
5¼ in | double | 512 | 8 | 80 | 2 | 640 KB | 360 | MFM | ||
9 | 720 KB | |||||||||
high | 15 | 1200 KiB | ||||||||
1024 | 8 | 77 (80) | 1232 (1280) KB | |||||||
3½ in (90 mm) | double | 512 | 8 | 80 | 2 | 640 KB | 360 | MFM | ||
9 | 720 KB | |||||||||
high | 15 | 1200 KB | 3mode | |||||||
1024 | 8 | 77 (80) | 1232 (1280) KB | |||||||
512 | 18 | 80 | 1440 KB | 300 | ||||||
SHARP X68000 | 5¼ in | high | 1024 | 8 | 77 | 2 | 1232 KB | 360 | MFM | |
3½ in (90 mm) |
Read more about this topic: List Of Floppy Disk Formats
Famous quotes containing the words disk and/or logical:
“Unloved, that beech will gather brown,
This maple burn itself away;
Unloved, the sun-flower, shining fair,
Ray round with flames her disk of seed,
And many a rose-carnation feed
With summer spice the humming air;”
—Alfred Tennyson (18091892)
“Opera, next to Gothic architecture, is one of the strangest inventions of Western man. It could not have been foreseen by any logical process.”
—Kenneth MacKenzie Clark, Baron of Saltwood (19031983)