Chapter 3 - Operation; About The Led Indicators - Multitech MT5656ZDX-Series User Manual

Your Multi-Tech modem operates under the control of a communications program. For information on how to
use the modem with your communications program, please refer to the documentation provided with the data
communications program.
An experienced modem user can configure the program's software to change the way the software interacts with
a modem and configure the modem to change the way it operates.

About the LED Indicators

The modem has ten LED indicators on the front panel that indicate status and activity:
TD Transmit Data
Flashes when the modem is transmitting data to another modem.
RD Receive Data
Flashes when the modem is receiving data from another modem.
CD Carrier Detect
Lights when the modem detects a valid carrier signal from another modem. It is on when the
modem is communicating with the other modem, and off when the link is broken.
OH Off-Hook
Lights when the modem is off-hook, which occurs when the modem is dialing, online, or
answering a call. The LED flashes when the modem pulse-dials.
TR Terminal Ready
Lights when a communication program is using the modem. It means the modem is ready for an
outgoing or incoming call. It goes off when the communication program disconnects the serial
port. When it goes off, a connected modem will disconnect.
Note: When you turn on the modem, the PWR indicator lights; and if a terminal program is running, the TR
indicator also lights.
Multi-Tech Systems, Inc. MT5656ZDX User Guide

Chapter 3 - Operation

Front Panel
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