Nortel Networks Circuit Card 사용자 설명서

 NT5D11 and NT5D14 Lineside T1 Interface cards

The lineside T1 card contains a microcontroller that controls the internal 
operation of the card and the serial card LAN link to the controller card. The 
microcontroller controls the following:

•

reporting to the CPU via the card LAN link:

— card identification (card type, vintage, serial number)

— firmware version

— self-test results

— programmed unit parameter status

•

receipt and implementation of card configuration:

— control of the T1 line interface

— enabling/disabling of individual units or entire card

— programming of loop interface control circuits for administration of 

channel operation

— maintenance diagnostics

•

interface with the line card circuit:

— converts on/off-hook, and ringer control messages from the DS-30X 

loop into A/B bit manipulations for each time slot in the T1 data 
stream, using robbed bit signaling.

•

the front panel LED when the card is enabled or disabled by instructions 
from the NT8D01 controller card.

Maintenance data is exchanged with the CPU over a dedicated asynchronous 
serial network called the Card LAN link.

The lineside T1 card also contains a sanity timer that resets the 
microcontroller in the event of a loss of program control. The microcontroller 
must service the sanity timer every 1.2 seconds. If the timer is not properly 
serviced, it times out and causes the microcontroller to be hardware reset.