IBM 9 Track
From Wikipedia, the free encyclopedia
IBM's System/360, released in 1964, introduced what is now generally known as 9 track tape. The magnetic tape is 1/2 inch wide and there are 8 data tracks and one parity track for a total of 9 parallel tracks. Data is stored as 8-bit characters, spanning the full width of the tape (including the parity bit).
Contents |
[edit] Generations
| IBM Model | 2400 Series | 3400 Series |
|---|---|---|
| Model numbers | 2401, 2415, 2420, 2440 | 3410, 3420, 3422, 3440 |
| Density (bytes/in) | 800, 1600 | |
| Tape speed (in/s) | 18.75 - 200 | |
| Transfer rate (B/s) | 15,000 - 320,000 | |
| Interblock gap (in) | 0.6 | |
| Rewind speed (in/s, avg.) | ||
| Start time (ms) | ||
| Stop time (ms) | ||
| Length of reel (ft) | 2400 | |
| Base composition | Plastic |
[edit] 2400 Series
The 2400 Series Magnetic Tape Units were introduced with the System/360. Some models had a 7 track read/write head and the 7 track compatibility option which made these 9 track units compatible with the older 7 track units.
[edit] 3400 Series
The 3400 Series Magnetic Tape Units were introduced with the System/370.
[edit] Notes
The standard size of a byte was effectively set at 8 bits with the S/360 and 9 track tape. This convention has continued through to 2006.
[edit] External link
| Magnetic tape data storage formats | ||
|---|---|---|
| Linear | Helical-Scan | |
| Three Quarter Inch (~19 mm) |
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| Half Inch (12.65 mm) |
UNISERVO (1951) - IBM 7 Track (1952) - IBM 9 Track (1964) - IBM 3480 (1984) - DLT (1984) - IBM 3590 (1995) - T9840 (1998) - T9940 (2000) - LTO Ultrium (2000) - T10000 (2006) |
Redwood SD-3 (1995) - DTF (19xx) - SAIT (2003) |
| Eight Millimeter (8 mm) |
Travan (1995) - IBM 3570 MP (1997) |
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| Quarter Inch (6.35 mm) |
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| Four Millimeter (3.8 mm) |
DDS/DAT (1989) |
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| One Eighth Inch (3.18 mm) |
KC Standard, Compact Cassette (1975) - Datassette (1977) |
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| Stringy (1.58 - 1.9 mm) |
Exatron Stringy Floppy (1979) - ZX Microdrive (1983) - Rotronics Wafadrive (1984) |
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