5. Testing
5-8
February 2001
8700-A2-GB25-10
Data Terminal Loopback
A 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 SYNC Data Port Tests screen.
2. Press Enter.
The Start command is changed to Stop.
3. To manually stop the test, verify that the cursor is positioned at the Stop
command.
4. Press Enter.
The Data Terminal Loopback cannot be started when a Repeater Loopback,
DCLB, or Remote DCLB is already active on the data port.
98-15933
NTU/LTU
Network
Interface
Port
Interface
Framer
EIA-530
Port
CAP
All 1s