Specifications
Installation and Operation Manual Chapter 5 Troubleshooting and Diagnostics
ASMi-52CQ Ver. 2.12 Testing ASMi-52CQ 5-11
Setting Loopback Tests
ASMi-52CQ supports the local analog loopback, remote digital loopbacks as per
ITU V.54.
V.54 loopback connections are set from the RADview SNMP management tool or
from an ASCII terminal (see
Section
5.2
) The TST LED on the front panel of the
local unit lights up and remains lit while the loopback is being run.
The loopback is activated separately for each modem on the ASMi-52CQ card;
therefore, you can run loopback for different modems on the card
simultaneously.
The loopback test runs until the timeout period has passed or the test is
cancelled (see
Table
5-5
). You cancel running a loopback from the RADview SNMP
management tool or from an ASCII terminal (see
Section
5.2
). Once a loopback is
cancelled, the TST indicators turn off. In case of the LLB, synchronization
between the modems is restored within a few minutes.
Running the Local Analog Loopback
The local analog loopback (LLB) checks the performance of the local ASMi-52CQ
modem, the local DTE and connection between them (see
Figure 5-5
).
The LLB can be performed separately on the local and remote modems.
LLB of the local unit is activated either from the terminal or from the SNMP
management tool. LLB is activated separately per port.
LLB of the remote unit is activated per port from the remote DTE, from the
terminal, or from the SNMP management tool.
ASMi-52CQ allows you to set the LLB timeout causing the loopback to deactivate
automatically after the desired period of time (see
Table
5-5
).
Data
Local ASMi-52CQ
Data
Clock
Clock
Line
Interface
Transmit
Receive
Local
DTE
Glue
Logic
Figure
5-5. Local Analog Loopback (LLB)
Running the Remote Digital Loopback
The remote digital loopback (RLB) checks the performance of both the local
ASMi-52CQ and remote ASMi-52 modems, and the lines connecting them
(see
Figure
5-6
).
RLB can be activated from the remote standalone ASMi-52 with software revision
1.12 or higher.