Dte Control Leads And Status - ADTRAN DSU IV ESP User Manual

Going To DBU - This message is displayed briefly while switching
from the dedicated service to dial backup mode.
In Dial Backup - The DSU is in dial backup mode.
LL Test From Telco - An LL test has been initiated from the telco.
Loop is Normal - The DSU is connected to the dedicated line.
OOS/OOF - The telco is transmitting an out-of-service code.
Open Loop - The DDS physical connection has been broken.
Waiting for Call - The DBU module is waiting for a call.

DTE Control Leads and Status

Four additional DTE interface leads are displayed with their
current status (on or off) displayed below. The leads are identified
as follows:
TR - Data terminal ready
SR - Data set ready
LLB - Local loopback
RLB - Remote loopback.
61204011L1-1 DSU IV ESP User Manual
Chapter 14. Viewing Status Information
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