2–8
DECbridge 500/600 Problem Solving
•
Check that the bridge’s configuration switches are set correctly (see Chapter
4). In particular, make sure that:
–
The Manufacturing Mode switch (switch 1) is in the OFF (up) position.
–
The Enable External Loopback switch (switch 7) is in the OFF (up) posi-
tion if you are not performing external loopback tests.
–
The AUI/ThinWire switch (switch 8) in a DECbridge 500 series unit is in
the ON (down) position if the AUI interface is used, or in the OFF (up)
position if the ThinWire interface is used.
•
Ensure that the interface cable connections are secure. The FDDI cable con-
nector(s) must be pushed securely into place in the bridge connector(s). The
AUI cable connector locks in place with a slide latch. Push the slide latch to
the left to make sure it snaps in the locking position. Make sure the BNC con-
nectors used by the ThinWire interface cable are twisted securely in place.
Also, make sure the proper termination is used.
•
For single-mode connections, ensure that the transmit and receive cables are
not reversed.
•
Ensure that the FDDI connections follow the rules specified in Appendix B.
•
Ensure that all the logic modules are seated firmly in their backplane connec-
tors and that the ejector levers for each module are pushed inward (locking
position).
•
Consider possible environmental problems such as power fluctuations or high
ambient temperature.
