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Connecting the T640 Router to an External Clocking Device


To connect the router to one or two external clocking devices, connect a cable with RJ-48 connectors to one of the EXTERNAL CLOCK INPUTS ports on the SCG.

  1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
  2. Plug one end of the cable into the appropriate EXTERNAL CLOCK INPUTS port on the SCG.
  3. Plug the other end of the cable into the T1 external clocking device.
  4. Repeat the procedure for the other EXTERNAL CLOCK INPUTS port on the SCG.
  5. Verify that the LINK LED for each port is lit steadily green.
  6. Configure the port. See the synchronization statement for M Series and T Series in the .
  7. Issue the show chassis synchronization command to check the status of the port.
    user@host> show chassis synchronization