Verilink PRISM 3301 (34-00239.5) Product Manual - Manual (Page 34)

26 C HAPTER 4: T ERMINAL I NTERFACE
Test Commands The TEST commands perform loop and system tests on the unit. The PRISM 3301
provides three loopback options to assist in diagnosing transmission difficulties.
These loopbacks can isolate a specific section of the transmission line allowing
accurate testing of line integrity and transmission devices. Each command is
followed by one or more keywords with each keyword separated by a space.
Only one loopback can be performed at a time.
TEST LOOP LOCAL DTE SET
This command performs a local DTE loopback test. The Local DTE Loopback can
be initiated and cleared from either user interface. The Local DTE Loopback loops
the incoming data from the local DTE back directly through the DTE connector
interface, after the digital receive circuit, as shown in Figure 4-3. During the
loopback, and AIS signal is sent to the network.
Figure 4-3 Local DTE Loopback
TEST LOOP LOCAL DTE CLEAR
This command clears the local DTE loopback test.
TEST LOOP LOCAL LINE SET
This command performs a local line loopback test. The Local Line Loopback can
be activated and cleared from either user interface. The Local Line Loopback loops
the DTE data back through the digital transmit and receive section of the PRISM
3301, as shown in Figure 4-4. When a local line loopback is active, an AIS signal
is sent to the network.
Figure 4-4 Local Line Loopback
TEST LOOP LOCAL LINE CLEAR
This command clears the local line loopback test.
TEST LOOP REMOTE SET
This command performs a remote loopback test.
✍
DTE DTE
Local 3301 Remote 3301
P
DTE
Local 3301 Remote 3301
DTE