CSGNetwork.com Free Information

Floppy Disk Information

These tables are presented as information for the most widely used and popular various stages of floppy disk and diskette history, leading to the current generation of floppy drives in the IBM PC compatible computers. The information here is not intended to show all manufacturers, drives, computers, schemes or devices that were available to the technology sector in general. You may also wish to see our Removable Media Information.

Floppy Diskette Data Storage Standards For Compatible PCs
  360KB
DSDD
(1976)
720 KB
DSDD
(1980)
1.2 MB
DSHD
(1978)
1.44 MB
DSHD
(1984)
2.88 MB
DSED
(1988-IBM)
Bit density (max) BPI 5,876 8717 9869 17434 34868
Bytes per Cluster 1024 1024 512 512 1024
Bytes per Sector 512 512 512 512 512
Clusters 354 713 2371 2847 2863
Coating Coercivity (oersteds) 290 650 660 720 1200
Coating Thickness (micrometers) 2.5 1.9 1.3 0.9 0.9
Dimensions 5¼" 3½" 5¼" 3½" 3½"
Directory Entries 112 112 224 112 240
Directory Sectors 7 7 14 14 15
DOS Version Requirement v1.0-3.0 v3.2 v3.0 v3.3 v5.0
FAT Type 12-bit 12-bit 12-bit 12-bit 12-bit
File Allocation Tables 2 2 2 2 2
Formatted Bytes 368640 737280 1228800 1474560 2949120
Heads 2 2 2 2 2
Interface MFM MFM MFM MFM MFM
Magnetic Coating Type Ferrite Ferrite Cobalt Cobalt Barium
Media Density Low Low High High Extra-High
Media Descriptor Byte FDH F9H F9H F0H F0H
RPM 300 300 300 300/360 300/360
Sectors 720 1440 2400 2880 5760
Sectors per Cluster 2 2 1 1 2
Sectors per FAT 2 3 7 9 9
Sectors per Track 9 9 15 18 36
Tracks 40 80 80 80 80
Tracks per Inch 48 135 96 135 135

Standard 34-Pin
Floppy Drive Connector Cable
Drive A:
Connector
Drive B:
Connector:
Function   Drive A:
Connector
Drive B:
Connector:
Function
1 1 Ground 18 18 Direction (Stepper Motor)
2 2 Unused 19 19 Ground
3 3 Ground 20 20 Step Pulse
4 4 Unused 21 21 Ground
5 5 Ground 22 22 Write Data
6 6 Unused 23 23 Ground
7 7 Ground 24 24 Write Enable
8 8 Index 25 25 Ground
9 9 Ground 26 26 Track 0
16 10 Motor Enable A 27 27 Ground
15 11 Ground 28 28 Write Protect
14 12 Drive Select B 29 29 Ground
13 13 Ground 30 30 Read Data
12 14 Drive Select A 31 31 Ground
11 15 Ground 32 32 Select Head 1
10 16 Motor Enable B 33 33 Ground
17 17 Ground 34 34 Unused

Diskette Innovation Timeline
Year Capacity Size Sides Density
1971 1.0 KB 8" 1 Single
1973 256 KB 8" 1 Single
  160 KB 8" 1 Single
  320 KB 8" 1 Double
1978 512 KB 8" 1 Double
  720 KB 8" 2 Double
  1.2 MB 8" 2 Double
1976 160 KB 5¼" 1 Double
1976 180 KB 5¼" 1 Double
1978 320 KB 5¼" 2 Double
1978 360 KB 5¼" 2 Double
  720 KB 5¼" 2 Double
1978 1.2 MB 5¼" 2 High
1980 720 KB 3½" 2 Double
1984 1.44 MB 3½" 2 High
1988 2.88 MB 3½" 2 Quad
1996 120 MB 3½" 2 Ultra-High
Version 1.0.1


Leave us a question or comment on Facebook
Search or Browse Our Site
Free Information Calculators and Converters

International Copyright Violation
Registered® Trademark™ and Copyrightę 1973 - CSG, Computer Support Group, Inc. and CSGNetwork.Com All Rights Reserved

Home | Advertising | Calculators and Converters | Contact Us | Javascript | Sitemap | Glossary | Top Free Apps