Chapter 6 Troubleshooting
Loopback Tests
6-4
TC8518 Rev 2.2 User Manual
Figure 6-6 Loopback Unit Diagram
6.6.1
T1/E1 Local Loopback Test
Local loopback is used to test wiring and the T1/E1 transceiver functionality. It can
be enabled and disabled by sending a CSU Loop-up (10000) or Loop-down (100)
pattern from the T1/E1 electrical side.
6.6.2
Optical Local Loopback Test
Optical local loopback tests if the optical transceivers on the local TC8518 are
operating properly.
6.6.3
Ethernet Local Loopback Test
Ethernet local loopback tests if the Ethernet capabilities on the local TC8518 are
operating properly.
6.6.4
T1/E1 Remote Loopback Test
T1/E1 Remote Loopback tests both the remote TC8518's optical transceivers and its
T1/E1 capabilities. Please refer to Figure 6-8,
.
6.6.5
Ethernet Remote Loopback Test
Ethernet Remote Loopback tests the remote TC8518's optical transceivers and
Ethernet capabilities.