GLOSSARY
DEFINITY Communications System
7400B Data Module
Page GL-2
User’s Guide
Data metering. A selectable feature of the 7400B Data Module that
allows the device and its associated terminal to operate at a higher speed
than the remote system to which it is connected.
Data mode. See on-line mode.
Data options. For asynchronous data communications, these
parameters include data transfer speed (expressed in bits/second or bps,
and sometimes called baud rate), parity, data word size (or data bits),
and stop bits. Generally, these parameters must be set to match at both
ends of the communication line. Except when the data metering option
is enabled, the 7400B data module attempts to adjust to match the speed
of the remote device. Also called communications parameters. See also
asynchronous data communications and data metering.
Data Terminal Equipment. (DTE) A device that sends and/or receives
data over a communication line via a DCE. Examples of DTE devices
are a display terminal, a PC running appropriate data communications
software, or a printer or plotter.
DCE. See Data Communications Equipment.
DCP. See Digital Communications Protocol.
Dial modifier. Any character that may be inserted in a command line
following the D (dial) command. See D command in Appendix A, "AT
Command Set," for a description of valid dial modifiers.
Digital Communications Protocol (DCP). A proprietary digital
protocol used by AT&T PBX equipment to communicate with AT&T
voice terminals and data modules. DCP supports simultaneous voice
and data services over the same line.
DTE. See Data Terminal Equipment.
D8W. A standard modular telephone cord used to connect DCP devices
to a PBX wall jack.
EIA-232-D. A US industry standard interface for digital data
communications equipment, established by EIA (the Electronics
Institute of America). The standard defines the cabling, connectors, and
lead signal assignments used in the interface. Formerly referred to as
the EIA Recommended Standard RS-232-C.
Hayes compatible. Of a DCE device, using the AT command set and
performing in close compliance with the configuration and operating
standards established by Hayes Microcomputer Products, Inc. See also
AT command set.
Idle mode. An operational mode in which the 7400B Data Module is
onhook waiting either for an incoming call or to originate a call.