B-18 Compact T1 - Release 6.1
Diagnostices & Troubleshooting
Loopbacks Overview
V.35/V.54 Loop

V.35/V.54 Service Card Description

The V.35 Card with V.54 Loop Test provides the capability for the V.35 card to
detect network loop back initiation signals and provide a network loop back for
loop testing. Each channel of the V.35 will continuously monitor the incomi ng data
bit stream for a particular loop pattern. On detection of the patt ern the chann el will
acknowledge the loop test request and put the channel into loop back. The channel
will then continuously monitor for the loop test end pattern. On detection of the
loop end pattern the channel will remove loop back and resume normal operation.
Front panel LED’s will indicate Loop test. Each channel can also initiate the loop
test pattern causing another V.54 compatible device to loop back. The channel will
then transmit a test pattern and calculate bi t error rate (BER).
View V.35/V.54 Card Configuration
Where a V.35/V.54 card is in slot 6.
> show 6:1
SLOT 6:
Settings for V35 Port 1:
CTS: Always High
Timing: Source
Rx Clock Inversion: Normal
Tx Clock Inversion: Normal
Data Inversion: Normal
Data Speed: 64K
Data Rate: 768 K
V.54 Rx LB: disabled
V.54 Rx Addr: 255
V.54 Test Addr: 255
V.54 Tx Prep count: 15
V.54 Rx Prep count: 15
V.54 Test Pattern: QRSS
V.54 Ignore ACK: OFF
Loopback: None