IBM AT 5170 Technical Reference page 482

symbol. (1) A conventional representation of a concept.
(2)
A representation of something by reason of relationship,
association, or convention.
synchronization. The process of adjusting the corresponding
significant instants of two signals to obtain the desired phase
relationship between these instants.
Synchronous Data Link Control (SDLC). A protocol for
management of data transfer over a data link.
synchronous transmission.
(1)
Data transmission in which the
time of occurrence of each signal representing a bit is related to a
fixed time frame.
(2)
Data transmission in which the sending and
receiving devices are operating continuously at substantially the
same frequency and are maintained, by means of correction, in a
desired phase relationship.
syntax.
(1)
The relationship among characters or groups of
characters, independent of their meanings or the manner of their
interpretation and use.
(2)
The structure of expressions in a
~
language.
(3)
The rules governing the structure of a language.
(4)
The relationships among symbols.
text. In ASCII and data communication, a sequence of
characters treated as an entity if preceded and terminated by one
STX and one ETX transmission control character, respectively.
time-out.
(1)
A parameter related to an enforced event designed
to occur at the conclusion of a predetermined elapsed time.
A time-out condition can be cancelled by the receipt of an
appropriate time-out cancellation signal.
(2)
A time interval
allotted for certain operations to occur; for example, response to
polling or addressing before system operation is interrupted and
must be restarted.
track.
(1)
The path or one of the set of paths, parallel to the
reference edge on a data medium, associated with a single reading
or writing component as the data medium moves past the
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