Owner`s manual

9
Chapter 1 - Introduction and Description
Front Panel Indicators
The MultiDSU64K has seven diagnostic LED indicators. They are:
DSU64K
CTSCD RD
SD
Send RCV Carrier Clear Request On LineTest
RTS
OL
TM
Multi-Rate DSU-CSU
®
Figure 1-3. LED Indicators
SD Transmit (Send) Data: This LED blinks when data is
being transmitted, on for a space, off for a mark.
RD Receive Data: This LED blinks when data is being
received, on for a space, off for a mark.
CD Carrier Detect: This LED is lit when a valid signal
from the remote DSU is detected. This indicator is off
if the DSU receives an idle code. If RTS is off at the
remote DSU, then the network sends an idle code to
the local DSU.
CTS Clear To Send: The CTS (Clear to Send) LED lights
when the MultiDSU64K generates a CTS in response
to either an RTS signal received at the DTE connector,
or RTS forced on by the corresponding DIP-Switch.
RTS Request To Send: The RTS LED lights when the RTS
signal is received from the DTE. The DIP-Switch for
RTS Forced On does not affect this indicator. Refer to
Chapter 2 for switch settings.
OL On Line: The OL (On Line) LED lights to indicate the
MultiDSU64K has detected a signal from the network.
TM Test Mode: The TM LED lights when either Local
Loopback (to DTE), Remote Digital Loopback, Digital
Loopback (to line) or Test Pattern DIP-Switches are
enabled. If the Test Pattern DIP-Switch is enabled,
then the TM LED blinks when errors are detected.
When the TM LED is lit, network transmit/receive
operation cannot occur. Refer to the “Diagnostic” Tests
section for more information.