TM 11-5815-602-10
EE161-DM-OPI-010/E154UGC74
TO 31W4-2UGC74-1
BEL :
A character for use when there is a need to call for human attention. It may control alarm
or attention devices.
(Backspace): A format effecter which controls the movement of the printing position one
BS
printing space backward on the same printing line (applicable also to visual display devices).
(Line Feed): A format effecter which controls the movement of the printing position to the
LF
next printing line (applicable also to visual display devices). Where appropriate, this character
may have the meaning "New Line" (N L), a format effecter which controls the movement of the
printing point to the first printing position on the next printing line. Use of this convention re-
quires agreement between sender and receiver of data. (So long as the current operating pro-
cedure of ending (or beginning) a line with CR-CR-LF is observed, no operational problem arises
from interconnecting "NL" and "Non-NL" machines.)
(Vertical Tabulation): A format effecter which controls the movement of the printing position
VT
to the next in a series of predetermined printing lines (applicable also to visual display devices).
(Form Feed): A format effecter which controls the movement of the printing position to the
FF
first predetermined printing line on the next form or page (applicable also to visual display
devices).
CR (Carriage Return): A format effecter which controls the movement of the printing position to
the first printing position on the same printing line (applicable also to visual display devices).
SO (Shift Out): A control character indicating that the code combinations which follow shall be
interpreted as outside of the character set of the standard code table until a Shift In Character(s)
is (are) reached.
Sl (Shift In): A control character indicating that the code combinations which follow shall be in-
terpreted according to the standard code table.
(Data Link Escape): A communication control character which will change the meaning of
DLE
a limited number of succession following characters. It is used exclusively to provide supplemen-
tary controls in data communication networks. DLE is usually terminated by a Shift In
character(s).
D C1, D C2,
DC3, DC4 (Device controls): Characters for the control of ancillary devices
associated with data processing or telecommunication systems; more especially switching
devices "on" or "off". (If a single "stop" control is required to interrupt or turn off ancillary
devices, DC4 is the preferred assignment.)
NAK (Negative Acknowledge): A communication control character transmitted by a receiver as
a negative response to the sender.
SYN (Synchronous Idle): A communication control character used by a synchronous transmis-
sion system in the absence of any other character to provide a signal from which synchronism
may be achieved or retained.
ETB (End of Transmission Block): A communication control character used to indicate the end
of a block of data for communication purposes. ETB is used for blocking data where the block
structure is not necessarily related to the processing format.
E-8
Previous Page
