Issue 2 November 1996 GL-1

GL

A

Asynchronous data communications
A method of communicating data in which each character (a 7- or 8-bit data word) is
sent or received separately at a selectable data transfer rate, and is framed by extra bits
preceding and following the character. Various error-checking methods use the total
bit-count to determine whether the character received at one end of the data path is the
same as the one sent at the other end. Also called asynchronous mode, this method, as
opposed to synchronous mode, does not use a clock signal to meter data. (Since the
8400B Plus Data Module operates only in asynchronous mode, s ynchrono us mode i s not
defined in this glossary.) See also data options.
AT command set
A de facto industry-standard set of commands used for configuration and operation of
DCE devices or modems. The AT (Attention) command set originated with Hayes
Microcomputer Products, Inc. The Lucent Te chnologies 8400B Plus Data Module uses a
subset of the full AT command set.

C

Command files
Files created for or by data communications s oftware running on a PC that can be used
to execute a sequence of commands to complete a task, such as performing an
automatic login to a specific remote device. Also called script files.
Command line
A string of one or more valid and compatible AT commands typed on one line with any
applicable arguments. Most command lines begin with the AT prefix and end with a
carriage return (issued by pressing ).
Command mode
An operating mode in which the 8400B Plus Data Module looks at all characters coming
from its associated terminal device and attempts to interpret them as commands. See
also on-line mode.
ENTER
Glossary