Specifications

1-48
Cisco ONS 15454 Troubleshooting and Maintenance Guide
November 2001
Chapter 1 Alarm Troubleshooting
Step 2 If the alarm does not clear when the coding and framing of the ONS 15454 match the coding and framing
of the signal source, replace the DS3XM-6 card.
Note When you replace a card with an identical type of card, you do not need to make any changes
to the database.
1.3.69 LOF (BITS)
• Major, Service affecting
A port on the TCC+ BITS input detects an LOF on the incoming BITS timing reference signal. LOF
indicates that the receiving ONS 15454 has lost frame delineation in the incoming data.
Note The procedure assumes that the BITS timing reference signal is functioning properly. It also assumes
the alarm is not appearing during node turn-up.
Caution Always use the supplied electrostatic discharge wristband when working with a powered ONS 15454.
Plug the wristband cable into the ESD jack located on the lower-right outside edge of the shelf
assembly.
Procedure: Clear the LOF Alarm on the TCC+ Card
Step 1 Verify that the line framing and line coding match between the BITS input and the TCC+:
a. In CTC node view or card view, note the slot and port reporting the alarm.
b. Find the coding and framing formats of the external BITS timing source. This should be in the user
documentation for the external BITS timing source or on the timing source itself.
c. Click the Provisioning > Timing tabs to display the General Timing screen.
d. Verify that Coding matches the coding of the BITS timing source (either B8ZS or AMI).
e. If the coding does not match, click Coding to reveal a menu. Choose the appropriate coding.
f. Verify that Framing matches the framing of the BITS timing source (either ESF or SF [D4]).
g. If the framing does not match, click Framing to reveal the menu. Choose the appropriate framing.
Note On the timing subtab, the B8ZS coding field is normally paired with ESF in the Framing
field, and the AMI coding field is normally paired with SF (D4) in the Framing field.
Step 2 If the alarm does not clear when the line framing and line coding match between the BITS input and the
TCC+, replace the TCC+ card.