Nortel Networks Video Gaming Accessories 553-3001-211 Manual De Usuario

 NT5D33 and NT5D34 Lineside E1 Interface cards

The MMI monitors the E1 link according to parameters established through 
the Set Alarm command for the following conditions:

•

Excessive bit error rate

•

Frame slip errors

•

Out of frame condition

•

Loss of signal condition

•

Blue alarm (AIS) condition

Descriptions of the excessive bit error rate and frame slip errors conditions 
are found in “Configuring parameters” on page 278. Bit errors activate either 
a level 1 or level 2 alarm. The remaining conditions, when detected, always 
cause the system to activate a level 2 alarm.

An out-of-frame condition will be declared if 3 consecutive frame bits are in 
error. If this condition occurs, the hardware immediately attempts to reframe. 
During the reframe time, the E1 link is declared out-of-frame, and silence is 
sent on all receive timeslots.

A loss of signal condition is declared if a full frame (255 bits) of consecutive 
zeros has been detected at the receive inputs. If this condition occurs, the E1 
link automatically attempts to resynchronize with the far-end. If this 
condition lasts for more than two seconds, a level 2 alarm is declared, and 
silence is sent on all receive timeslots. The alarm is cleared if, after two