TU81 Streaming Tape Unit
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Revision as of 23:45, 10 January 2022 by Jnc (talk | contribs) (Jnc moved page TU81 to TU81 magtape drive: Follow naming system)
TU81 | |
Manufacturer: | Digital Equipment Corporation |
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Media: | standard half-inch tape |
Tape density: | 1600 bpi (PE), 6250 bpi (GCR) |
Tape speed: | 75 inch/sec (high speed streaming mode) or 25 inch/sec (start/stop mode or low-speed streaming mode) |
Year Introduced: | 1984/1985 |
Big 9-track magnetic tape drive for heavy backup duties.
The TU81 servo/control module uses a Motorola 6802 processor, a variant of the 6800 with 128 bytes of internal RAM and an internal clock oscillator. There is also a 6821 Parallel Interface Adapter chip used for communication between the Servo/Control microprocessor and the Formatter Write microprocessor (on a different board).
Two 6840 Programmable Counter / Programmable Timer Module chips are used to count servo tachs.
The firmware is stored in two ROM chips.