Comtech EF Data CIC-50, Инструкция по установке и эксплуатации

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CIC-50 T1/E1 G.703 Interface Converter .
Rev. 1 5
4
Chapter 4.
INDICATORS AND
TROUBLESHOOTING
After configuring both the CDM-550 and the CIC-50, two indicators are available on the
CIC-50 to monitor the condition of the incoming G.703 data. If no marks are received
over 175 bit times at T1 or 32 bit times at E1, the Loss Of Signal LED will illuminate.
This will not activate an alarm on the CDM-550, but the CIC-50 will generate AIS (all
ones) data into the modem timed directly off the internal clock reference provided to it.
Therefore, activating the TX-AIS alarm will allow the modem to indirectly monitor this
condition.
The other indicator is the Bipolar Violation LED. AMI coding dictates that each mark
received at the G.703 input be of alternating polarity. Enabling the HDB3/B8ZS line
coding presumes the use of zero substitution patterns that include intentional Bipolar
Violations (BPV). Since this LED will be pulsed with each BPV found, it will not only
illuminate when format errors are present, but also if the incoming data is using
HDB3/B8ZS while the CIC-50 is set for AMI. This mismatch will cause errors in the data
path and should be corrected. It is recommended that HDB3/B8ZS always be selected on
the CIC-50’s switch unless the user is certain that line coding will never be present.
Note:
CDM-550 only - if using software releases before Version 1.10, the I/O LOOP test
mode will not operate properly with the CIC-50. Please call the factory for a free
software upgrade. The CDM-550T is not affected.