Nortel Networks 553-3001-211 manual NT5D33 and NT5D34 Lineside E1 Interface cards Page 247

NT5D33 and NT5D34 Lineside E1 Interface cards Page 247 of 894

—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 E1 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 E1 data stream, using channel associated signaling.

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

Card LAN interface

Maintenance data is exchanged with the Common Equipment CPU over a dedicated asynchronous serial network called the Card LAN link. The Card LAN link is described in “Card LAN link” on page 34.

Sanity Timer

The LEI also contains a sanity timer that resets the microcontroller in the event of a loss of program control. If the timer is not properly serviced by the microcontroller, it times out and causes the microcontroller to be hardware-reset. If the microcontroller loses control and fails to service the sanity timer at least once per second, the sanity timer will automatically reset the microcontroller, restoring program control.

Man-Machine Interface

The LEI provides an optional Man-Machine Interface (MMI) that is primarily used for E1 link performance monitoring and problem diagnosis. The MMI

Circuit Card Description and Installation