Definition Of Terms - IBM 3164 ASCII Manual

This glossary defines terms and abbreviations that are
used in this manual. If you do not find the term you
are looking for, refer to the Index or to the IBM
Vocabulary for Data Processing, Telecommunications,
and Office Systems, GC20-1699.
Definitions from American National Standard Institute
(ANSI) are identified with an asterisk. An asterisk
between a term and the beginning of a definition
indicates that the entire definition is taken from
American National Dictionary for Information
Processing.
The symbol "(ISO)" at the beginning of a definition
indicates that it was developed by the International
Standard Organization, Technical Committee 97,
Subcommittee 1. Definitions from early working
papers of ISO are identified by the symbol "(SCI)."
ASCII.
American National Standard Code for
Information Interchange. The standard code, using a
coded character set consisting of 7/8-bit coded
characters, used for information interchange among
data processing systems, data communication
systems, and associated equipment. The ASCII set
consists of control characters and graphic characters.
attribute character. A code that defines the
display attributes of the display field that follows. An
attribute character is the first character in a display
field, but it is not a displayable character.
audible alarm. An alarm that is activated when
predetermined events occur that require operator
attention or intervention for system operation.
block.
(1) A string of records, a string of words, or
a character string formed for technical or logic reasons
to be treated as an entity. (2) A set of things, such
as words, characters, or digits, handled as a unit.
block transfer. The process, initiated by a single
action, of transferring one or more blocks of data.
buffer. An area of storage that is temporarily
reserved for use in performing an input/output
operation, into which data is read, or from which data
is written. Synonymous with I/O area.
Definition of terms
buffer address.
The address of a location in the
buffer at which one character can be stored.
buffer-print operation. An operation that prints
the contents of the buffer from the IBM 3164 to an
attached printer.
cathode ray tube (CRT). A vacuum tube display
in which a beam of electrons can be controlled to
form alphanumeric characters or symbols on a
luminescent screen, for example, by use of a dot
matrix.
character. (1) A member of a set of elements upon
which agreement has
be~n
reached and that is used
for the organization, control, or representation of data.
Characters may be letters, digits, punctuation marks,
or other symbols often represented in the form of a
spatial arrangement of adjacent or connected strokes,
or in the form of other physical conditions, in data
media. (2) A letter, digit, or other symbol that is- used
as part of the organ ization, control, or representation
of data.
character mode. An operating mode of the IBM
3164 in which data is transferred character by
character in either half-duplex or duplex.
character position. Synonym for display position.
communication controller. A type of
communication control unit whose operations are
controlled by one or more programs stored and
executed in the unit; for example, the IBM 3704/3705
and the 3725/3726 Communication Controllers.
control character. A character whose occurrence
in a particular context initiates, modifies, or stops a
control operation. A control character may be
recorded for use in a subsequent action, and it may
have a graphic representation in some circumstances.
controlled-request-to send (CRTS). A line
control used on a half-duplex or duplex facility for an
alternate one-way data transmission. When a terminal
begins the data transmission to a host system, it turns
on the request-to-send (RTS) signal which stays on
until the terminal transmits a turnaround character.
cursor. In computer graphics, a movable marker that
is used to indicate a position on a display space.
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