Troubleshooting

 

Diagnostic Tests

 

Testing a Transceiver on an Ethernet/802.3 Port

 

 

N o t e :

This test verifies that data written out is identical to data received and

 

that no collisions are detected. This test can be done with transceivers

 

(sometimes termed MAUs) such as the HP 28685B EtherTwist

 

Transceiver, the HP 28641B ThinLAN Transceiver, and the HP 28683A

 

Fiber-Optic Transceiver. (Some transceivers have a loopback test

 

switch that must be set to correspond to these requirements.)

 

1. Set the XCVR Signal Polling parameter to the default ‘‘Active’’ for the

 

circuit on the LAN port to be tested. To access this parameter, use

 

the Configuration Editor from the console, select item 4 (‘‘Circuits’’)

 

select the desired LAN port, and specify the Circuit Type parameter.

 

The console then displays the XCVR Signal Polling parameter. (For

 

information on the XCVR Signal Polling parameter, refer to the

 

Operator’s Reference.).

 

2. Detach the router’s power cord.

 

3. Attach the transceiver to the LAN port, and attach the required type

 

of loopback connector to the transceiver. If the transceiver has a

 

loopback test switch, enable it for the test.

 

4. Reattach the router’s power cord.

 

5. If the Net Fail LED for the tested LAN port remains unlit when

 

self-test completes after about one to three minutes, the transceiver

 

is OK and this procedure is finished. If the Net Fail LED for a tested

 

LAN port lights, then proceed to the next step.

 

6. Detach the router’s power cord and detach the transceiver from the

 

router. Attach an AUI loopback connector to the LAN port in place

 

of the transceiver. Reattach the router’s power cord. If the Net Fail

 

LED for the tested LAN port remains unlit this time, the transceiver

 

is probably faulty. If the Net Fail LED for the tested port lights, the

 

router’s port is faulty.

Troubleshooting 3

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