Testing
7-8 7112-A2-GB20-20
March 1998
Data Terminal Loopback
Data Terminal Loopback (DTLB) loops the user data back to the DTE. This
loopback is located as closely as possible to the User Data Port (DTE) interface.
Procedure
To run a data terminal loopback:
1. Position the cursor at the Start command next to Data Terminal Loopback on
the Data Port Tests screen and press Enter.
The Start command is changed to Stop.
2. To manually stop the test, verify that the cursor is positioned at the Stop
command and press Enter.
97-15696

CSU DSU

Network
Interface
DTLB
DTE
Port 1
ALL 1s
Data Terminal Loopback cannot be started when any other loopback is already
active on the data port.