Automated Tape Library (ATL) Definition/Meaning:
A peripheral device in which a large number of
cartridges or reels of magnetic tape are stored in cells in a storage matrix.
Any chosen
cartridge can be transferred mechanically to a tape transport (directly or by
way of a further mechanism called a shuttle) where it can be accessed by the
host system, and then retuned to the same or another cell. The device also
contains one or more drawers that can also be reached by the transfer mechanism:
these are accessible to an operator so that cartridges can be introduced to or
removed from the library. An ATL is functionally equivalent to a conventional
tape library but without the need for a human operator except to add or remove
cartridges. In one brand of ATL, standard reels of 1/2" tape are used, but more
often the cartridge is specially designed for the purpose and generally contains
a single reel with a relatively short length of tape several inches wide. The
virtues of the ATL are the rapidity with which any cartridge can be selected and
mounted on the transport, typically a few seconds, and the elimination of human
operators. Its disadvantages are cost and mechanical and functional complexity.
At the time of writing (1983) ATLs are not widely used.
An equivalent
arrangement for storing and accessing optical disks is likely to come into use
in the 1980s; prototypes already exist.
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