AT&T DataPort PCX Modem User Manual page 75

Glossary
CD
Carrier Detect. A signal between the local and remote ends of a
network indicating that energy exists on the transmission circuit.
Associated with Pin 8 on an RS-232 interface.
chassis ground
Pin 1 of an RS-232 interface.
Class 1
A fax modem standard. Under Class 1 computer software
handles most of the protocol, compression, and conversion
tasks.
COM port
A computer's serial communications port used to transmit to and
receive data from a modem. The modem connects directly to
this port.
Command mode
One of two general operating modes; the other is Data mode.
When in Command mode, the modem accepts commands
instead of transmitting or receiving data.
communications software
Software installed on a computer that controls the modem.
configuration option
Modem software that sets specific operating parameters for the
modem. Sometimes referred to as straps.
CTS
Clear To Send. A signal, sent to the computer via Pin 5 of an
RS-232 interface, indicating that the modem is ready for the
computer to transmit data.
Issue 2 July 1995
GL-3